Title of Invention	HIGHLY FLOWABLE PROPYLENE BLOCK COPOLYMERS
Abstract	The invention relates to highly flowable propylene block copolymers that comprise 50 to 80 wt.- % of a propylene homopolymer and 10 to 70 wt.- % of a propylene copolymer having 5 to 50 wt.- % of a C¿2?-C¿8? alk-1-ene polymerized into it that is different from propylene, and that are obtainable from the gaseous phase by a two-step polymerization by means of a Ziegler-Natta catalyst system. In a first polymerization step, the propylene is polymerized at a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and an average dwelling time of the reaction mixture of 0.3 to 5 hours in the presence of at least 2.0 % by volume, based on the total volume, of hydrogen. The propylene homopolymer obtained in said first polymerization step is transferred together with the Ziegler-Natta catalyst system into an intermediate container, expanded for 0.01 to 5 minutes to less than 5 bar and maintained at a temperature of 10 to 80 °C. The pressure in the intermediate container is then increased by 5 to 60 bar by introducing under pressure a gaseous mixture, and the propylene homopolymer is then transferred to a second polymerization step together with the Ziegler-Natta catalyst system. In said second polymerization step, a mixture from propylene and a C¿2?-C¿8? alk-1-ene is polymerized into the propylene homopolymer at a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and an average dwelling time of 0.5 to 5 hours. The weight ratio between the monomers reacted in the first and those reacted in the second polymerization step are adjusted to be in the range of from 4:1 to

Title of Invention

HIGHLY FLOWABLE PROPYLENE BLOCK COPOLYMERS

Abstract

The invention relates to highly flowable propylene block copolymers that comprise 50 to 80 wt.- % of a propylene homopolymer and 10 to 70 wt.- % of a propylene copolymer having 5 to 50 wt.- % of a C¿2?-C¿8? alk-1-ene polymerized into it that is different from propylene, and that are obtainable from the gaseous phase by a two-step polymerization by means of a Ziegler-Natta catalyst system. In a first polymerization step, the propylene is polymerized at a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and an average dwelling time of the reaction mixture of 0.3 to 5 hours in the presence of at least 2.0 % by volume, based on the total volume, of hydrogen. The propylene homopolymer obtained in said first polymerization step is transferred together with the Ziegler-Natta catalyst system into an intermediate container, expanded for 0.01 to 5 minutes to less than 5 bar and maintained at a temperature of 10 to 80 °C. The pressure in the intermediate container is then increased by 5 to 60 bar by introducing under pressure a gaseous mixture, and the propylene homopolymer is then transferred to a second polymerization step together with the Ziegler-Natta catalyst system. In said second polymerization step, a mixture from propylene and a C¿2?-C¿8? alk-1-ene is polymerized into the propylene homopolymer at a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and an average dwelling time of 0.5 to 5 hours. The weight ratio between the monomers reacted in the first and those reacted in the second polymerization step are adjusted to be in the range of from 4:1 to

Full Text	Highly free-flowing Propylene block co-polymers Description: The above-mentioned invention relates to a highly free-flowing propylene block copolymer, consisting of 50 to 80-weight % of a Pwith 10 to 70 weight % of a single polymerized Propylene of different C2-C8-Alk-ls, obtainable through two stage polymerization by means of a Ziegler-Natta-Catalyst System, from the gaseous phase. In so doing, in a first polymerization stage, under a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and a medium dwell time of the reaction compound of 0,3 to 5 hours in the presence of minimum 2 Volume %, with reference to the total volume of hydrogen, propylene is polymerized and then the propylene homo-polymer obtained in the first polymerization stage with the Ziegler-Natta-Catalyst system is collected in an intermediate Container. There, to start with it is de-stressed for a period of 0,01 to 5 minutes at less than 5 bar and maintained at a temperature of 10 to 80 °C, and finally through infusion of a gas compound the pressure in the intermediate Container is enhanced again by 5 to 60 bar and then the propylene homo-polymer obtained with the Ziegler-Natta-Catalyst system is transferred to a second polymerization stage. There, under a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and a mean dwell-time of 0,5 to 5 hours, the Propylene homo-polymer, a compound from Propylene and a C2-C8-Alk-ls, is polymerized and in so doing, the weight ratio between the Manomers converted in the first and the second polymerization stages is so measured that it lies in the range of 4:1 to 1:1. Furthermore, the above invention relates to a process for manufacture of such highly free-flowing Propylene block co-polymers as well as their application as foils, yams or formed bodies. Propylene-Ethylene-Block co-polymers, obtainable through polymerization under Ziegler-Natta-Catalyst system are already described in several patent documents (US-A 4 454 299, US-A 4 455 405, DE-A 3 827 565, DE-A 4 004 087). Such block copolymers are customarily manufactured according to a process in which, one starts with the polymerization of the gaseous propylene in a first polymerization stage and brings the resultant Propylene homo-polymers finally in a second polymerization stage, where a compound made of Propylene and Ethylene is additionally polymerized. The process is carried out customarily under enhanced pressure and in the presence of hydrogen as Mol mass regulator. The Propylene-Ethylene-Block Co-polymer thus obtained have often a good impact resistance and stiffness. The Propylene Block Co-Polymers, which have a high degree of rubber proportion, that means, block co-polymers in which the co-polymer obtained in the second polymerization stage represents a higher share in the total Block co-polymer, can be achieved under the usual polymerization process only for relatively low melt-flow rates direct from the Reactor. This is attributable, among others, to the fact that the high degree of hydrogen concentration necessary for regulating the Mol mass of the Block co-polymer is practically not realizable. Further, in the manufacture of Block copolymers, with high degree of rubber and a relatively high melt flow rate, one would often observe an undesirable deposit build-up in the second polymerization stage, connected with problems of Morphology of the products obtained. For these reasons, from the process point of view, it is very difficult to manufacture rubber-rich Propylene Block co-polymers which possess simultaneously a property of high impact resistance in conjunction with a high degree of flow, that means, their melt flow rates have high values. A possibility to produce rubber-rich Propylene Block co-polymers, which possess a high degree of flow, exists in that, the rubber-rich Propylene block co-polymers are subjected to a subsequent Mol mass reduction with the help of organic peroxides, as a result of which, their melt flow rate and the resultant flowing property could be significantly enhanced. However, such a Mol mass reduction necessitates a relatively expensive additional process step. Furthermore, use of organic peroxides bring in its train a series of disadvantages such as, among others, enhanced emission of low molecular particles, odour nuisance, as well as (penalties in the form of) stiffness, heat forming resistance and softening behaviour. organic aluminium compounds b) and Electron donor compounds c). In this fashion, the Propylene block co-polymers, as per the invention is accessible. For the manufacture of titanium-containing solid components a) the Halogenide or alcoholates of the trivalent or quadrivalent titanium, whereby also titan-alcoxy halogen compounds or compounds of different titanium compounds can be considered. Preferably the titanium compounds, which contain chlorine as halogen are used. Similarly, the titan halogenides, which contain besides titanium only halogen, are preferred and in this context above all, the titanium chloride and especially Titan Tetrachloride. The Titanium containing solid components a) includes preferably at least one halogen containing magnesium compound. What is understood herein as halogen are chlorine, Brom, Jod or Fluor, where Brom or especially Chlorine are preferred. The halogen-containing magnesium compounds are either directly applied during the manufacture of the titanium containing fixed components 'a' or generated during their manufacture. As magnesium compounds, which are suitable for manufacture of titanium-containing fixed components a), the magnesium halogenide occupies the first position such as particularly, Magnesium chloride or Magnesium bromide or Magnesium compounds, from which the Halogenide can be obtained generally, for instance, through decomposition or conversion with halogenisation materials such as magnesium alkyl, magnesium aryl, magnesium alkoxy or magnesium aryloxy compounds or Grignard compounds. Preferred examples for halogen-free compounds of the magnesium, which are suitable for manufacturing titanium-containing fixed components a) are n-Butyi Ethyl magnesium or n-Butyloctyl magnesium. Preferred halogenisation materials are chlorine or hydrochlorine. Also Titanium halogenide could however serve as halogenisation material. Moreover, the titanium-containing fixed components a) contain electron donor compounds, for instance, mono or poly functional carbonic acid, carbonic acid anhydride or carbonic acid ester, further Keton, Ether, Alcohol, Lactone or phosphorous or silicon organic compounds. Within the Titanium containing solid components, carbonic acid derivative and Phtal acid derivative of the general formula (II) are preferably used as Electron donor components, whereby, X and Y respectively represent a Chlorine or Brom atom or a Ci-C10-Alkoxy residue or jointly for oxygen in Anhydride function. Especially preferred electron donor compounds are: Phthal acid ester, where X and Y represent a Ci-Cg-Alkoxy residue. Examples for preferred phthal acid ester are Diethyl phthalat, Di-n-butyl phthalat, Di-iso-butyl phthalat, Di-n-pentyl phthalat, Di-n-hexyl phthalat, Di-n-heptyl phthalat, Di-n-octyl phthalat or Di-2-ethyl hexyl phthalat. Other preferred electron donor compounds, within the titanium containing solid components are Diester of 3 or 4-branch or chain, where applicable substituted cycIoalkyl-1, 2-dicarbonic acid as well as Monoester of substituted Benzophenon-2-carbonic acid or substituted Benzophenon-2-carbonic acid. In these esters, alcanols In the manufacture of titanium containing solid components a) , generally per Mol of the magnesium compound of 0,05 to 2,0 mol, preferably 0,2 to 1,0 mol of the Electron donor compounds are mixed. Further, the titanium containing solid components a) can also contain inorganic oxides as carrier. Generally, a fine particle inorganic oxide is used as carrier, which has a mean particle diameter of 5 to 200 \|am, preferably from 20 to 70 \|im. What is meant by mean particle diameter is the volume based mean value of the grain size distribution, determined through the Couher-Counter-Analysis. Ideally, the grains of the fine particle inorganic oxides consist of primary particles, which have a mean particle diameter of the primary particle of 1 to 20 \xm, especially 1 - 5 µm. The so-called primary particles relate to porous granular oxide particles, which have been generally obtained through grinding or a hydrogel of the inorganic oxide. It is also possible to filter the primary particles before their further processing. Further, the inorganic oxide to be used preferably is also characterized thereby, that they have hollow space and/or channels with mean diameter of 0,1 to 20 µm, specially from 1 to 15 µm, whose macroscopic volume proportion on the total particle is in the range of 5 to 30%, preferably in the range of 10 to 30%. The determination of the mean particle diameter of the primary particle as well as the macroscopic volume proportion of the hollow space and channels of the inorganic oxides is purposefully done through image analysis, with the help of the Scarming Electron Microscope (Raster Electron Microscope) and/or the Electron Probe Micro Analysis (Electron X-ray-Micro range analysis) on the grain surfaces and on grain cross sections of the inorganic oxide respectively. The exposures are evaluated and therefrom the mean particle diameter of the primary particle as well as the macroscopic volume portion of the hollow round and channels are determined. The image analysis is done preferably through transferring the electron microscopic Data in a Grey Value Binary Image; the digital evaluation is done using a suitable Computer Program, for instance, the Software-Packet Analysis of the company SIS. The inorganic oxide to be used can be obtained for example through spray drying of the ground hygrogels, which for this purpose is mixed with water or an aliphatic alcohol. Such fine particle inorganic oxides are also obtainable in the market. The fine particle inorganic oxides has also ordinarily a pore volume of 0,1 to 10 cm /g, ideally from 1,0 to 4,0 cm3/g and a specific surface of 10 to 1000 m2/g, ideally 100 to 500 m3/g, whereby the values referred to here are to be understood as those obtained through Queck silver-Porosimetric as per DIN 66133 and through Nitrogen -Adsorption as per DIN 66131. It is also possible to use an inorganic oxide, the pH-value of which, that means, the negative decadic Logarithm of the Proton Concentration, is in the range of 1 to 6,5 and preferably in the range of 2 to 6. The oxides of Silicon, Aluminium, Titanium or one of the metals of I and/or II of tne Main Group of the Period System are to be considered as the inorganic oxides. Besides aluminium oxide or manganese oxide or sheet silicate, silicon oxide, (silicon gel) is used as a specially preferred oxide. Also, mixed oxides such as aluminium silicate or manganese silicate can also be used. The inorganic oxides used as carriers contain water on their surface. This water is bound partly physically through adsorption and partly chemically in the form of Hydroxyl groups. Through thermal or chemical treatment, the water content of the inorganic oxide can be reduced or totally removed, where in respect of the chemical treatment, generally SiCl4, Chlorsilane or Aluminium alkyl are used as drying material. The water content of the suitable inorganic oxide should be from 0 to 6-weight %. An inorganic oxide in the form in which it is obtainable in the market is used v^thout any further treatment. The magnesium compound and inorganic oxide within the titanium containing solid components a) should be preferably in such quantities that per Mol, preferably from 0,2 to 0,5 Mil, the compound of the Magnesium is found. In the manufacture of the titanium-containing solid components a) the following groups generally come to be applied. Farther C1 to C6-Alcanol such as Methanol, Ethanol, n-Propanol, Isopropanol, n-ButanoI, tert-Butanol, Isobutanol, n-Hexanol, n-HeptanoI, n-Oktanol or 2-Ethyl hexanol or their compounds.. The titanium containing solid components can be manufactured according to known methods. Examples in this context are described, among others, in EP-A 45 975, EP-A 45v 977, EP-A 86 473, EP-A 171 200, GB-A 2 111 066 of the US-A 857 613 and the US-A 5 288 824. Ideally, it is manufactured based on the process described in DE-A 195 29 240. Suitable aluminium compounds b) besides Tri-alkyl aluminium are also such compounds in which an alkoxy group is mixed by means of an aluminium group or through a halogen atom, for example through chlorine or Brom. The Alkyl groups can be identical or different from each other. Linear or branched alkyl groups come into consideration. Preferably, Tri-alkyl aluminium compounds are used, whose alkyl groupshave respectively 1 to 8 C-atom, for instance, Tri-methyl aluminium, Tri-ethyl aluminium, Tri-iso-butylalmimium, Trioctyl aluminium or Methyl Diethyl aluminium or compounds thereof. Generally, besides the aluminium compound b) one also uses as additional catalyst electron donor compounds c) such as Mono-functional or Poly-functional carbonic acids, carbon acid anhydride or carbonic acid ester, farther Ketone, Ether, Alcohol, Lactone, as well as phosphorous and silicon organic compounds where the Electron Donor compounds c) could be identical or different from the Electron donor Compounds used for the manufacture of the titanium-containing solid components a). Preferred Electron donor compounds are silicon organic compounds of the general formula (I) Among these compounds the following are to be preferred Dimethoxydiisopropylsilan, Dimethoxyisobutylisopropylislan, Dimethoxydiisobutylsilan, Dmethoxydicyclopentylsilan, Dimethoxyisopropyl-tert. -butylsilan,Diemethoxyisobutyl-sek.-butylsilan and Dimethoxyisopropyl-sek.-butylsilan. Preferably the co-catalysts b) and c) are applied in such quantities that the atom ratio between aluminium from the aluminium compounds b) and titanium from the titanium-containing solid components a) is between 10:1 to 800:1, especially between 20: 1 to 200:1 and the Mol ratio between the aluminium compound b) and the Electron donor compound c) from 1:1 to 250:1, especially from 10:1 to 80:1 The titanium containing solid components a), the aluminium compound b) and the generally used Electron donor compounds c) together build the Ziegler-Natta-Catalyst System, The Catalyst substances b) and c) could be added to the Polymerization reactor together with the Titanium-containing solid components c) as a mixture or even in optional sequence individually. The process for manufacture of the invention-based highly free - flowing Propylene Block Co-polymers is carried out in two subsequently operated polymerization stages that means, in a Reactor cascade, in the gas phase. The customary Reactors used for the Polymerization C2-C8-Alk Is can be used.. Suitable Reactors are, among others, continuously operated mixing boiler, loop Reactors or fluidized bed Reactors. The size of the Reactors is of no less importance for the Invention-based process. It depends on the yield, which must be achieved in the Reactor or in the individual Reactor Zone. Specially fluidized Bed Reactors as well as horizontally or vertically mixing powder Reactors are used. The Reaction Bed in the process as per the invention consists of in general, the Polymer C2-C8-Alk-ls, which is polymerized in the respective Reactor. In a specially preferred design form, the process used for the manufacture of the Invention-based Propylene Block Co-polymer, the process is carried out in a Cascade of subsequently operated Reactors in which the powder formed reaction bed is kept in motion through a vertical Mixer for which purpose the so-called Cantilevered spiral mixture is especially suitable. Such Mixers are known, among others, from EP-B 000 512 and the EP-B 031 417. They exemplify themselves by the fact that they distribute the powder formed Reaction bed very homogenously. Examples for such powder formed Reaction bed are described in EP-B 038 478. Preferably, the Reaction cascade consists of two subsequently operated boiler-formed reactors with a Mixer and with a capacity of 0,1 to 100m3 for example 12,5 25, 50 or 75 m3 During the polymerization for producing the invention-based Propylene block copolymer, its Mol mass can be controlled and set through the customary chain transfer agents used in Polymerization technology, for example through Hydrogen. Besides such agents, also so-called Reactors, that means, compounds, which influence the catalyst activity, or even anti-static properties can be used. The latter compounds prevent the build-up of deposit on the reactor walls through Electro Static Descaling. In the first polymerization stage, for products of the invention-based Propylene Block Co-Polymers under customary re-action conditions: Propylene is polymerized under a pressure of 10 to 50 bar, especially from 15 to 40 bar, a temperature of 50 to 100°C, especially 60 to 90 °C and under a mean dwell-time of 0,3 to 5 hours, preferably from 0,8 to 4 hours. For controlling the Mol mass of the Propylene homo-polymers in the first polymerization stage in the presence of at least 2,0 Volume % of hydrogen, the polymerization is done preferably with minimum 5,0 volume %, based on the total mix applicable for this polymerization stage The Propylene homo-polymers obtained in the first polymerization stage represents the so-called Matrix of the invention-based Propylene Block Co-polymers and possesses a Poly Dispersity Index (PI) of minimum 2,8, preferably at least 3,0. Subsequently, the Propylene homo-polymer obtained in the first Polymerization stage, using the Ziegler-Natta-Catalyst system, is removed from the first Polymerizatin stage and transferred in an intermediate container. The Reactors or customarily used Containers for the Polymerization C2-C8-Alk-ls are used as intermediate Coisainers. Suitable intermediate containers are, for example, cylindrical containers, mixing containers or even cyclones. Propylene homo-polymer transferred from the first Polymerization stage, together with the Ziegler-Natta-Catalyst system is de-stressed to start with for a duration of 0,01 to5 minutes, preferably 0,1 to 4 minutes, at less than 5 bar, preferably at less than 3,5 bar. During this time, one could also add to the Propylene homo-polymer, homo-polymer also 0,001g tolO g, preferably 0,001 g to 1,0 g of a Cl-C8-Alcanol per kg of the Propylene for better control of the subsequent Polymerization steps. For this purpose, Isopropanol, as also Ethanol or Glycol are especially suitable. The intermediate Container is maintained at a temperature of 10 to 20 °C, preferably between 20 to 70 °C, subsequently through injection of a gas mixture from the Monomers used, that means, Propylene as well as the C2-C8-Alk-ls, the pressure in the intermediate Container is enhanced again by 5 to 60 bar, preferably by 10 to 15 bar. In the intermediate Container, the Reaction mixture can also be converted using the customary anti-static substances, for example, Poly glycol ether of fatty alcohols, fatty acids and Alkyl phenol, Alkyl sulphate and alkyl phosphate as well as Quarter Ammonium compounds. Thereafter, the Propylene homo-polymers together with the Ziegler-Natta-Catalyst system is removed from the Intermediate Container and brought into the second Polymerization stage. In the second polymerization stage, the Propylene homo-polymer is additionally polymerized under a pressure of 10 to 50 bar, preferably 10 to 40 bar, with a temperature of 50 to lOO°C, preferably 60 to 90°C and a mean dwell-time of 0,5 to 5 hours, preferably from 0,8 to 4 hours, a mixture out of Propylene and a C2-C8-Alkls, In this process, the weight ratio between the Monomer obtained in the first and second polymerization stages is so measured that it lies in the range of 4:1 to 1:1, preferably in the range of 4:1 to 1,5:1. Similar to the case of the Intermediate Container, one could also add in the second polymerization stage, 0,001 g to 10 g, preferably 0,005 g to 0.5 g of a C1-C8-Alcanols. For this purpose, Iso-propanol, Glycol or also Ethanol recommend temselves as the most optimum. Suitable co-monomers of the Propylene in the second polymerization stage are, among others, Ethylene and But-Is. The share of this or these Co-monomers of the Propylene on the suitable gas mixture in the second polyTnerization stage should be preferably 15 to 60 Volume %, preferably 20 to 50 Volume %. The Propylene block co-polymer obtained in this manner according to the invention, has a Melt Flow Rate (MFR) as specified in ISO 1133, under 230T and a weight of 2,16 kg and would fit the following notation: (I) (I)MFR> 101,39 + 0,0787 ♦ XS2 - 5,4674XS where XS represents the share of the propylene co-polymer in percentage developed in the second polymerization stage, related to the total Propylene Block Co-Polymers. The Melt Flow Rate of the propylene block co-polymers obtained lie in general in the range of 2 to 100 g/10 min., preferably in the range of 5 to 80 g/10 min., respectively at 230°C and under a weight of 2,16 kg. The Melt Flow Rate corresponds in this context to the quantity of polymer, which is extruded within a period of 10 minutes from the testing device Normed according to ISO 1133 under a temperature of 230° C and under a weight of 2,16 kg. The Invention-based Propylene block co-polymers are manufactured without Mol mass reduction based on peroxide. The Invention based Propylene block co-polymers exemplify themselves, among others, through a high degree of flow capability, that means through an enhanced melt flow rate under simultaneous rubber proportion. This denotes that the proportion of the propylene block co-polymer in the total propylene block co-polymer is more. Further, the invention-based propylene block co-polymers are characterized through a high degree of impact resistance and stiffness as well as through a good heat-forming resistance and flow capability in injection moulding (spiral flow property). They contain with all this, only relatively less low molecular substances, as for instance, n-Hepten or tert.Butanol. Similarly the invention-based process can be carried out in the customary reaction of the plastic technology in a simple manner without the need for having the propylene block co-polymers subjected to a subsequent reduction of Mol mass. The invention based propylene block co-polymers are suitable, above all for manufacture of foils, fibres and formed bodies. Examples: In all the invention based examples 1, 2 and 3 as well as the comparative examples A, B and C, Zieger-Natta-Catalyst system was applied, which encompasses the titanium containing solid material a) manufactured according to the following process. In a first stage a fine particle silica gel, which has a mean particle dia of about 30 jim, a pore volume of 1,5 cm3/g and a specific surface of 260 m /g is added to a solution of n-Butyl Octyl Magnesium in n-Heptane, where per Mol Si02 0,3 mol of the magnesium compound was added. The fine particle silica gel was additionally characterized through a mean particle size of the primary particle of 3-5µm and through hollow space and canals with a dia of 3-5 µm, where the macroscopic volume proportion of the hollow space and canals on the total particle was about 15%. The solution was stirred for 45 minutes under 95°C, thereafter cooled to 20°C, after which the 10-time molar quantity, based on the magnesium organic compound in hydrogen chloride, was introduced. After 60 minutes, the reaction product was added under constant stirring with 3 mol ethanol per mol magnesium was added. This mixture was stirred 0,5 hours under 80°C and subsequently was added with 7,2 mol Titanium Tetrachloride and 0,5 mol Di-n-Butyl Phthalate each respectively based on 1 mol magnesium. Finally the compound was stirred for one hour under 100°C, and the solid stuff thus obtained filtered and washed with ethyl benzene several times. The solid product obtained therefrom is extracted for three hours under 125°C with a lO-volume-% solution of titanium tetrachloride in ethyl benzene. Thereafter the solid product was separated through filtration from the extraction material and washed with n-Heptane so long till the extraction material had only of 0,3 weight-% of titanium tetrachloride. The titanium containing solid components a) contain: 3,5weight-%Ti 7,4 weight-% Mg 28,2 weight-% CI Besides the titanium containing solid components a) Tri-ethyl Aluminium and Di-methoxy Isobutyl Isopropylsilan were used as co-catalysts analogous to the gauge of US-A 4 857 613 and the US-A 5 288 824. Example 1, 2 and 3 The process was carried out in all invention-related examples 1, 2 and 3 in two adjacent mixing auto claves, equipped with a cantilevered spiral mixture, with a rated volume of 200 1 each. Both reactors were provided with a movable fixed bed made of fine particle propylene polymer. In the first polymerization reactor, the propylene was added in gas form and under a medium dwell-time, under pressure and a temperature according to table 1 was polymerized. The Ziegler-Natta-Catalyst System deployed for this purpose consisted of the titanium containing solid components a) as well as tri-ethyl alummium and isobutyl isopropyl di-methoxy-silane as catalysts. In this process the dosage of the solid components was so measured that the transfer from the first into the second polymerization reactor in mean free time corresponded to the values indicated in Table 1. The dosage of these components was done with the fresh propylene added for the purpose of pressure regulation. Similarly the following were also added into the reactor: as further catalyst substances tri-ethyl aluminium (in the form of a 1 molar heptane solution) in a quantity of 60 to maximum 105 ml/hour, and Isobutyl Isopropyl di-methoxy-silane (in the form of a 0,125 molar heptane solution) in a quantity of 70 to maximum 120 ml/hour. For regulating the melt flow rate (as per ISO 1133) hydrogen was added, and the hydrogen concentration in the reaction gas was gas chromatographically controlled. By means of short-time recess of the reactors through an inunersion tube, successive polymer substance was removed firom the reactor. The propylene homo-polymer obtained in the first reactor was thereby discontinuously transferred with the catalysts into an intermediate container and converted there with Isopropanol (in the form of 0,5 molar heptane solution). The quantity of Isopropanol thus added -was so measured that the weight ratio between the propylene homo polymerisate obtained in the first reactor and the propylene propylene co-polymerisate produced in the secound reactor reached the values indicated in the following table I. The quantity of the Isopropanol added can also be split in a manner that it is added partially in the intermediate container and partially in the second reactor. In the intermediate container the pressure was reduced respectively to 1 bar and maintained at that level for 30 seconds long and fmally by injecting a gas mixture, corresponding to the composition in the second reactor, increased to 30 bar. The polymer powder was transferred thereafter discontinuously from the intermediate container to the second reactor. There under a total pressure a temperature and a mean dwell-time corresponding to Table I, a compound made of propylene and ethylene was added to it for polymerization. The proportion of ethylene amounted to about 30 volume-% each. The weight ratio between the propylene homo polymer created in the first reactor, and the propylene co-polymer generated in the second reactor was controlled with the addition of Isopropanol and is indicated in Table I. The precise conditions of the Example 1, 2 and 3 according to the Invention, that means the values for pressure, temperature and dwell-time, the quantity of hydrogen used, as well as the quantity of the co-catalysts, the melt-flow rate (MFR) and the transfer quantity, that means the quantity of the polymer respectively obtained for both polymerization reactors are given in the following Table I. Table I contains further the weight ratio between the propylene homo polymer obtained in the first polymerization reactor [PP (I)] and the propylene ethylene co-polymer (EPRII) obtained in the second polymerization reactor. The proportion of the propylene-ethylene-co-polymerisate generated in the second reactor is calculated from the transfer and discharge quantities according to the following formula: The process was carried out in all the invention-related examples 1', 2' and 3' in two adjacent mixing autoclaves, equipped with a cantilevered spiral mixture, with an effective volume of 200 1 each. Both reactors were provided with a movable fixed bed made of fine particle propylene polymer. In the first polymerization reactor, the propylene was given in gas form and polymerized under a given dwell-time of 2,3 hours with the help of a Ziegler-Natta-Catalyst made of titanium containing solid components a), tri-ethyl aluminium and isobutyl isopropyle di-methoxy silane under a pressure and temperature as per Table IL In so doing, the dosage of the slid components was so measured that the charge/transfer from the first to the second polymerization reactor on an average corresponded to the values indicated in Table II. The dosage of these components was done together with the fresh propylene added for the purpose of pressure regulation. Similarly the following were also added to the reactor: tri-ethyl aluminium (in the form of a 1 molar heptane solution). For purpose of regulating the melting flow rate (as per ISO 1133) hydrogen was added, and the hydrogen concentration in the reaction gas was gas chromatographically controlled. Using short-time de-stressing of the reactor by means of an immersion tube successive polymer grains were removed from the reactor. The propylene homo polymer generated in the first reactor was thus discontinuously charged into the second reactor with the catalyst and together with the unconverted or not decomposed monomers, without de-stressing them in an intermediate container. There under a total pressure, a temperature and a mean dwell-time corresponding to Table II, a mixture of propylene and ethylene it is further polymerized. The proportion of ethylene accounted for 30 volume-% each. The weight ratio between the propylene homo polymer [PP (I)] generated in the first reactor and the propylene co-polymer [EPR (II)] generated in the second reactor is indicated in Table II. The following was similarly added in the second reactor; Isopropanol (in the form of a 0,5 molar heptane solution). The quantity added of Isopropanol was so measured that the weight ratio between PP (I) and EPR (II) was maintained as per figures given in Table 11. Propylene block polymer obtained in the comparison examples 1', 2' and 3' was finally extruded, after a peroxide mol mass reduction with the help of a 5 weight-% solution of di-tert-butyl peroxide in n-Heptane (Luperox ® 101 of M/s. Interox/Peroxid Chemie) in a double-worm extruder (ZSK 30, Worm 8 A of M/s. Werner & Pfleiderer). In this manner, their melt flow rate (MFR) could be significantly enhanced. The melt flow rates before (MFR II) and after the reduction of the mol mass reduction (MFR after reduction) are indicated in the following Table II. Highly free-flowing Propylene block co-polymers Description: The above-mentioned invention relates to a highly free-flowing propylene block copolymer, consisting of 50 to 80-weight % of a Pwith 10 to 70 weight % of a single polymerized Propylene of different C2-C8-Alk-ls, obtainable through two stage polymerization by means of a Ziegler-Natta-Catalyst System, from the gaseous phase. In so doing, in a first polymerization stage, under a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and a medium dwell time of the reaction compound of 0,3 to 5 hours in the presence of minimum 2 Volume %, with reference to the total volume of hydrogen, propylene is polymerized and then the propylene homo-polymer obtained in the first polymerization stage with the Ziegler-Natta-Catalyst system is collected in an intermediate Container. There, to start with it is de-stressed for a period of 0,01 to 5 minutes at less than 5 bar and maintained at a temperature of 10 to 80 °C, and finally through infusion of a gas compound the pressure in the intermediate Container is enhanced again by 5 to 60 bar and then the propylene homo-polymer obtained with the Ziegler-Natta-Catalyst system is transferred to a second polymerization stage. There, under a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and a mean dwell-time of 0,5 to 5 hours, the Propylene homo-polymer, a compound from Propylene and a C2-C8-Alk-ls, is polymerized and in so doing, the weight ratio between the Manomers converted in the first and the second polymerization stages is so measured that it lies in the range of 4:1 to 1:1. Furthermore, the above invention relates to a process for manufacture of such highly free-flowing Propylene block co-polymers as well as their application as foils, yams or formed bodies. Propylene-Ethylene-Block co-polymers, obtainable through polymerization under Ziegler-Natta-Catalyst system are already described in several patent documents (US-A 4 454 299, US-A 4 455 405, DE-A 3 827 565, DE-A 4 004 087). Such block copolymers are customarily manufactured according to a process in which, one starts with the polymerization of the gaseous propylene in a first polymerization stage and brings the resultant Propylene homo-polymers finally in a second polymerization stage, where a compound made of Propylene and Ethylene is additionally polymerized. The process is carried out customarily under enhanced pressure and in the presence of hydrogen as Mol mass regulator. The Propylene-Ethylene-Block Co-polymer thus obtained have often a good impact resistance and stiffness. The Propylene Block Co-Polymers, which have a high degree of rubber proportion, that means, block co-polymers in which the co-polymer obtained in the second polymerization stage represents a higher share in the total Block co-polymer, can be achieved under the usual polymerization process only for relatively low melt-flow rates direct from the Reactor. This is attributable, among others, to the fact that the high degree of hydrogen concentration necessary for regulating the Mol mass of the Block co-polymer is practically not realizable. Further, in the manufacture of Block copolymers, with high degree of rubber and a relatively high melt flow rate, one would often observe an undesirable deposit build-up in the second polymerization stage, connected with problems of Morphology of the products obtained. For these reasons, from the process point of view, it is very difficult to manufacture rubber-rich Propylene Block co-polymers which possess simultaneously a property of high impact resistance in conjunction with a high degree of flow, that means, their melt flow rates have high values. A possibility to produce rubber-rich Propylene Block co-polymers, which possess a high degree of flow, exists in that, the rubber-rich Propylene block co-polymers are subjected to a subsequent Mol mass reduction with the help of organic peroxides, as a result of which, their melt flow rate and the resultant flowing property could be significantly enhanced. However, such a Mol mass reduction necessitates a relatively expensive additional process step. Furthermore, use of organic peroxides bring in its train a series of disadvantages such as, among others, enhanced emission of low molecular particles, odour nuisance, as well as (penalties in the form of) stiffness, heat forming resistance and softening behaviour. organic aluminium compounds b) and Electron donor compounds c). In this fashion, the Propylene block co-polymers, as per the invention is accessible. For the manufacture of titanium-containing solid components a) the Halogenide or alcoholates of the trivalent or quadrivalent titanium, whereby also titan-alcoxy halogen compounds or compounds of different titanium compounds can be considered. Preferably the titanium compounds, which contain chlorine as halogen are used. Similarly, the titan halogenides, which contain besides titanium only halogen, are preferred and in this context above all, the titanium chloride and especially Titan Tetrachloride. The Titanium containing solid components a) includes preferably at least one halogen containing magnesium compound. What is understood herein as halogen are chlorine, Brom, Jod or Fluor, where Brom or especially Chlorine are preferred. The halogen-containing magnesium compounds are either directly applied during the manufacture of the titanium containing fixed components 'a' or generated during their manufacture. As magnesium compounds, which are suitable for manufacture of titanium-containing fixed components a), the magnesium halogenide occupies the first position such as particularly, Magnesium chloride or Magnesium bromide or Magnesium compounds, from which the Halogenide can be obtained generally, for instance, through decomposition or conversion with halogenisation materials such as magnesium alkyl, magnesium aryl, magnesium alkoxy or magnesium aryloxy compounds or Grignard compounds. Preferred examples for halogen-free compounds of the magnesium, which are suitable for manufacturing titanium-containing fixed components a) are n-Butyi Ethyl magnesium or n-Butyloctyl magnesium. Preferred halogenisation materials are chlorine or hydrochlorine. Also Titanium halogenide could however serve as halogenisation material. Moreover, the titanium-containing fixed components a) contain electron donor compounds, for instance, mono or poly functional carbonic acid, carbonic acid anhydride or carbonic acid ester, further Keton, Ether, Alcohol, Lactone or phosphorous or silicon organic compounds. Within the Titanium containing solid components, carbonic acid derivative and Phtal acid derivative of the general formula (II) are preferably used as Electron donor components, whereby, X and Y respectively represent a Chlorine or Brom atom or a Ci-C10-Alkoxy residue or jointly for oxygen in Anhydride function. Especially preferred electron donor compounds are: Phthal acid ester, where X and Y represent a Ci-Cg-Alkoxy residue. Examples for preferred phthal acid ester are Diethyl phthalat, Di-n-butyl phthalat, Di-iso-butyl phthalat, Di-n-pentyl phthalat, Di-n-hexyl phthalat, Di-n-heptyl phthalat, Di-n-octyl phthalat or Di-2-ethyl hexyl phthalat. Other preferred electron donor compounds, within the titanium containing solid components are Diester of 3 or 4-branch or chain, where applicable substituted cycIoalkyl-1, 2-dicarbonic acid as well as Monoester of substituted Benzophenon-2-carbonic acid or substituted Benzophenon-2-carbonic acid. In these esters, alcanols In the manufacture of titanium containing solid components a) , generally per Mol of the magnesium compound of 0,05 to 2,0 mol, preferably 0,2 to 1,0 mol of the Electron donor compounds are mixed. Further, the titanium containing solid components a) can also contain inorganic oxides as carrier. Generally, a fine particle inorganic oxide is used as carrier, which has a mean particle diameter of 5 to 200 \|am, preferably from 20 to 70 \|im. What is meant by mean particle diameter is the volume based mean value of the grain size distribution, determined through the Couher-Counter-Analysis. Ideally, the grains of the fine particle inorganic oxides consist of primary particles, which have a mean particle diameter of the primary particle of 1 to 20 \xm, especially 1 - 5 µm. The so-called primary particles relate to porous granular oxide particles, which have been generally obtained through grinding or a hydrogel of the inorganic oxide. It is also possible to filter the primary particles before their further processing. Further, the inorganic oxide to be used preferably is also characterized thereby, that they have hollow space and/or channels with mean diameter of 0,1 to 20 µm, specially from 1 to 15 µm, whose macroscopic volume proportion on the total particle is in the range of 5 to 30%, preferably in the range of 10 to 30%. The determination of the mean particle diameter of the primary particle as well as the macroscopic volume proportion of the hollow space and channels of the inorganic oxides is purposefully done through image analysis, with the help of the Scarming Electron Microscope (Raster Electron Microscope) and/or the Electron Probe Micro Analysis (Electron X-ray-Micro range analysis) on the grain surfaces and on grain cross sections of the inorganic oxide respectively. The exposures are evaluated and therefrom the mean particle diameter of the primary particle as well as the macroscopic volume portion of the hollow round and channels are determined. The image analysis is done preferably through transferring the electron microscopic Data in a Grey Value Binary Image; the digital evaluation is done using a suitable Computer Program, for instance, the Software-Packet Analysis of the company SIS. The inorganic oxide to be used can be obtained for example through spray drying of the ground hygrogels, which for this purpose is mixed with water or an aliphatic alcohol. Such fine particle inorganic oxides are also obtainable in the market. The fine particle inorganic oxides has also ordinarily a pore volume of 0,1 to 10 cm /g, ideally from 1,0 to 4,0 cm3/g and a specific surface of 10 to 1000 m2/g, ideally 100 to 500 m3/g, whereby the values referred to here are to be understood as those obtained through Queck silver-Porosimetric as per DIN 66133 and through Nitrogen -Adsorption as per DIN 66131. It is also possible to use an inorganic oxide, the pH-value of which, that means, the negative decadic Logarithm of the Proton Concentration, is in the range of 1 to 6,5 and preferably in the range of 2 to 6. The oxides of Silicon, Aluminium, Titanium or one of the metals of I and/or II of tne Main Group of the Period System are to be considered as the inorganic oxides. Besides aluminium oxide or manganese oxide or sheet silicate, silicon oxide, (silicon gel) is used as a specially preferred oxide. Also, mixed oxides such as aluminium silicate or manganese silicate can also be used. The inorganic oxides used as carriers contain water on their surface. This water is bound partly physically through adsorption and partly chemically in the form of Hydroxyl groups. Through thermal or chemical treatment, the water content of the inorganic oxide can be reduced or totally removed, where in respect of the chemical treatment, generally SiCl4, Chlorsilane or Aluminium alkyl are used as drying material. The water content of the suitable inorganic oxide should be from 0 to 6-weight %. An inorganic oxide in the form in which it is obtainable in the market is used v^thout any further treatment. The magnesium compound and inorganic oxide within the titanium containing solid components a) should be preferably in such quantities that per Mol, preferably from 0,2 to 0,5 Mil, the compound of the Magnesium is found. In the manufacture of the titanium-containing solid components a) the following groups generally come to be applied. Farther C1 to C6-Alcanol such as Methanol, Ethanol, n-Propanol, Isopropanol, n-ButanoI, tert-Butanol, Isobutanol, n-Hexanol, n-HeptanoI, n-Oktanol or 2-Ethyl hexanol or their compounds.. The titanium containing solid components can be manufactured according to known methods. Examples in this context are described, among others, in EP-A 45 975, EP-A 45v 977, EP-A 86 473, EP-A 171 200, GB-A 2 111 066 of the US-A 857 613 and the US-A 5 288 824. Ideally, it is manufactured based on the process described in DE-A 195 29 240. Suitable aluminium compounds b) besides Tri-alkyl aluminium are also such compounds in which an alkoxy group is mixed by means of an aluminium group or through a halogen atom, for example through chlorine or Brom. The Alkyl groups can be identical or different from each other. Linear or branched alkyl groups come into consideration. Preferably, Tri-alkyl aluminium compounds are used, whose alkyl groupshave respectively 1 to 8 C-atom, for instance, Tri-methyl aluminium, Tri-ethyl aluminium, Tri-iso-butylalmimium, Trioctyl aluminium or Methyl Diethyl aluminium or compounds thereof. Generally, besides the aluminium compound b) one also uses as additional catalyst electron donor compounds c) such as Mono-functional or Poly-functional carbonic acids, carbon acid anhydride or carbonic acid ester, farther Ketone, Ether, Alcohol, Lactone, as well as phosphorous and silicon organic compounds where the Electron Donor compounds c) could be identical or different from the Electron donor Compounds used for the manufacture of the titanium-containing solid components a). Preferred Electron donor compounds are silicon organic compounds of the general formula (I) Among these compounds the following are to be preferred Dimethoxydiisopropylsilan, Dimethoxyisobutylisopropylislan, Dimethoxydiisobutylsilan, Dmethoxydicyclopentylsilan, Dimethoxyisopropyl-tert. -butylsilan,Diemethoxyisobutyl-sek.-butylsilan and Dimethoxyisopropyl-sek.-butylsilan. Preferably the co-catalysts b) and c) are applied in such quantities that the atom ratio between aluminium from the aluminium compounds b) and titanium from the titanium-containing solid components a) is between 10:1 to 800:1, especially between 20: 1 to 200:1 and the Mol ratio between the aluminium compound b) and the Electron donor compound c) from 1:1 to 250:1, especially from 10:1 to 80:1 The titanium containing solid components a), the aluminium compound b) and the generally used Electron donor compounds c) together build the Ziegler-Natta-Catalyst System, The Catalyst substances b) and c) could be added to the Polymerization reactor together with the Titanium-containing solid components c) as a mixture or even in optional sequence individually. The process for manufacture of the invention-based highly free - flowing Propylene Block Co-polymers is carried out in two subsequently operated polymerization stages that means, in a Reactor cascade, in the gas phase. The customary Reactors used for the Polymerization C2-C8-Alk Is can be used.. Suitable Reactors are, among others, continuously operated mixing boiler, loop Reactors or fluidized bed Reactors. The size of the Reactors is of no less importance for the Invention-based process. It depends on the yield, which must be achieved in the Reactor or in the individual Reactor Zone. Specially fluidized Bed Reactors as well as horizontally or vertically mixing powder Reactors are used. The Reaction Bed in the process as per the invention consists of in general, the Polymer C2-C8-Alk-ls, which is polymerized in the respective Reactor. In a specially preferred design form, the process used for the manufacture of the Invention-based Propylene Block Co-polymer, the process is carried out in a Cascade of subsequently operated Reactors in which the powder formed reaction bed is kept in motion through a vertical Mixer for which purpose the so-called Cantilevered spiral mixture is especially suitable. Such Mixers are known, among others, from EP-B 000 512 and the EP-B 031 417. They exemplify themselves by the fact that they distribute the powder formed Reaction bed very homogenously. Examples for such powder formed Reaction bed are described in EP-B 038 478. Preferably, the Reaction cascade consists of two subsequently operated boiler-formed reactors with a Mixer and with a capacity of 0,1 to 100m3 for example 12,5 25, 50 or 75 m3 During the polymerization for producing the invention-based Propylene block copolymer, its Mol mass can be controlled and set through the customary chain transfer agents used in Polymerization technology, for example through Hydrogen. Besides such agents, also so-called Reactors, that means, compounds, which influence the catalyst activity, or even anti-static properties can be used. The latter compounds prevent the build-up of deposit on the reactor walls through Electro Static Descaling. In the first polymerization stage, for products of the invention-based Propylene Block Co-Polymers under customary re-action conditions: Propylene is polymerized under a pressure of 10 to 50 bar, especially from 15 to 40 bar, a temperature of 50 to 100°C, especially 60 to 90 °C and under a mean dwell-time of 0,3 to 5 hours, preferably from 0,8 to 4 hours. For controlling the Mol mass of the Propylene homo-polymers in the first polymerization stage in the presence of at least 2,0 Volume % of hydrogen, the polymerization is done preferably with minimum 5,0 volume %, based on the total mix applicable for this polymerization stage The Propylene homo-polymers obtained in the first polymerization stage represents the so-called Matrix of the invention-based Propylene Block Co-polymers and possesses a Poly Dispersity Index (PI) of minimum 2,8, preferably at least 3,0. Subsequently, the Propylene homo-polymer obtained in the first Polymerization stage, using the Ziegler-Natta-Catalyst system, is removed from the first Polymerizatin stage and transferred in an intermediate container. The Reactors or customarily used Containers for the Polymerization C2-C8-Alk-ls are used as intermediate Coisainers. Suitable intermediate containers are, for example, cylindrical containers, mixing containers or even cyclones. Propylene homo-polymer transferred from the first Polymerization stage, together with the Ziegler-Natta-Catalyst system is de-stressed to start with for a duration of 0,01 to5 minutes, preferably 0,1 to 4 minutes, at less than 5 bar, preferably at less than 3,5 bar. During this time, one could also add to the Propylene homo-polymer, homo-polymer also 0,001g tolO g, preferably 0,001 g to 1,0 g of a Cl-C8-Alcanol per kg of the Propylene for better control of the subsequent Polymerization steps. For this purpose, Isopropanol, as also Ethanol or Glycol are especially suitable. The intermediate Container is maintained at a temperature of 10 to 20 °C, preferably between 20 to 70 °C, subsequently through injection of a gas mixture from the Monomers used, that means, Propylene as well as the C2-C8-Alk-ls, the pressure in the intermediate Container is enhanced again by 5 to 60 bar, preferably by 10 to 15 bar. In the intermediate Container, the Reaction mixture can also be converted using the customary anti-static substances, for example, Poly glycol ether of fatty alcohols, fatty acids and Alkyl phenol, Alkyl sulphate and alkyl phosphate as well as Quarter Ammonium compounds. Thereafter, the Propylene homo-polymers together with the Ziegler-Natta-Catalyst system is removed from the Intermediate Container and brought into the second Polymerization stage. In the second polymerization stage, the Propylene homo-polymer is additionally polymerized under a pressure of 10 to 50 bar, preferably 10 to 40 bar, with a temperature of 50 to lOO°C, preferably 60 to 90°C and a mean dwell-time of 0,5 to 5 hours, preferably from 0,8 to 4 hours, a mixture out of Propylene and a C2-C8-Alkls, In this process, the weight ratio between the Monomer obtained in the first and second polymerization stages is so measured that it lies in the range of 4:1 to 1:1, preferably in the range of 4:1 to 1,5:1. Similar to the case of the Intermediate Container, one could also add in the second polymerization stage, 0,001 g to 10 g, preferably 0,005 g to 0.5 g of a C1-C8-Alcanols. For this purpose, Iso-propanol, Glycol or also Ethanol recommend temselves as the most optimum. Suitable co-monomers of the Propylene in the second polymerization stage are, among others, Ethylene and But-Is. The share of this or these Co-monomers of the Propylene on the suitable gas mixture in the second polyTnerization stage should be preferably 15 to 60 Volume %, preferably 20 to 50 Volume %. The Propylene block co-polymer obtained in this manner according to the invention, has a Melt Flow Rate (MFR) as specified in ISO 1133, under 230T and a weight of 2,16 kg and would fit the following notation: (I) (I)MFR> 101,39 + 0,0787 ♦ XS2 - 5,4674XS where XS represents the share of the propylene co-polymer in percentage developed in the second polymerization stage, related to the total Propylene Block Co-Polymers. The Melt Flow Rate of the propylene block co-polymers obtained lie in general in the range of 2 to 100 g/10 min., preferably in the range of 5 to 80 g/10 min., respectively at 230°C and under a weight of 2,16 kg. The Melt Flow Rate corresponds in this context to the quantity of polymer, which is extruded within a period of 10 minutes from the testing device Normed according to ISO 1133 under a temperature of 230° C and under a weight of 2,16 kg. The Invention-based Propylene block co-polymers are manufactured without Mol mass reduction based on peroxide. The Invention based Propylene block co-polymers exemplify themselves, among others, through a high degree of flow capability, that means through an enhanced melt flow rate under simultaneous rubber proportion. This denotes that the proportion of the propylene block co-polymer in the total propylene block co-polymer is more. Further, the invention-based propylene block co-polymers are characterized through a high degree of impact resistance and stiffness as well as through a good heat-forming resistance and flow capability in injection moulding (spiral flow property). They contain with all this, only relatively less low molecular substances, as for instance, n-Hepten or tert.Butanol. Similarly the invention-based process can be carried out in the customary reaction of the plastic technology in a simple manner without the need for having the propylene block co-polymers subjected to a subsequent reduction of Mol mass. The invention based propylene block co-polymers are suitable, above all for manufacture of foils, fibres and formed bodies. Examples: In all the invention based examples 1, 2 and 3 as well as the comparative examples A, B and C, Zieger-Natta-Catalyst system was applied, which encompasses the titanium containing solid material a) manufactured according to the following process. In a first stage a fine particle silica gel, which has a mean particle dia of about 30 jim, a pore volume of 1,5 cm3/g and a specific surface of 260 m /g is added to a solution of n-Butyl Octyl Magnesium in n-Heptane, where per Mol Si02 0,3 mol of the magnesium compound was added. The fine particle silica gel was additionally characterized through a mean particle size of the primary particle of 3-5µm and through hollow space and canals with a dia of 3-5 µm, where the macroscopic volume proportion of the hollow space and canals on the total particle was about 15%. The solution was stirred for 45 minutes under 95°C, thereafter cooled to 20°C, after which the 10-time molar quantity, based on the magnesium organic compound in hydrogen chloride, was introduced. After 60 minutes, the reaction product was added under constant stirring with 3 mol ethanol per mol magnesium was added. This mixture was stirred 0,5 hours under 80°C and subsequently was added with 7,2 mol Titanium Tetrachloride and 0,5 mol Di-n-Butyl Phthalate each respectively based on 1 mol magnesium. Finally the compound was stirred for one hour under 100°C, and the solid stuff thus obtained filtered and washed with ethyl benzene several times. The solid product obtained therefrom is extracted for three hours under 125°C with a lO-volume-% solution of titanium tetrachloride in ethyl benzene. Thereafter the solid product was separated through filtration from the extraction material and washed with n-Heptane so long till the extraction material had only of 0,3 weight-% of titanium tetrachloride. The titanium containing solid components a) contain: 3,5weight-%Ti 7,4 weight-% Mg 28,2 weight-% CI Besides the titanium containing solid components a) Tri-ethyl Aluminium and Di-methoxy Isobutyl Isopropylsilan were used as co-catalysts analogous to the gauge of US-A 4 857 613 and the US-A 5 288 824. Example 1, 2 and 3 The process was carried out in all invention-related examples 1, 2 and 3 in two adjacent mixing auto claves, equipped with a cantilevered spiral mixture, with a rated volume of 200 1 each. Both reactors were provided with a movable fixed bed made of fine particle propylene polymer. In the first polymerization reactor, the propylene was added in gas form and under a medium dwell-time, under pressure and a temperature according to table 1 was polymerized. The Ziegler-Natta-Catalyst System deployed for this purpose consisted of the titanium containing solid components a) as well as tri-ethyl alummium and isobutyl isopropyl di-methoxy-silane as catalysts. In this process the dosage of the solid components was so measured that the transfer from the first into the second polymerization reactor in mean free time corresponded to the values indicated in Table 1. The dosage of these components was done with the fresh propylene added for the purpose of pressure regulation. Similarly the following were also added into the reactor: as further catalyst substances tri-ethyl aluminium (in the form of a 1 molar heptane solution) in a quantity of 60 to maximum 105 ml/hour, and Isobutyl Isopropyl di-methoxy-silane (in the form of a 0,125 molar heptane solution) in a quantity of 70 to maximum 120 ml/hour. For regulating the melt flow rate (as per ISO 1133) hydrogen was added, and the hydrogen concentration in the reaction gas was gas chromatographically controlled. By means of short-time recess of the reactors through an inunersion tube, successive polymer substance was removed firom the reactor. The propylene homo-polymer obtained in the first reactor was thereby discontinuously transferred with the catalysts into an intermediate container and converted there with Isopropanol (in the form of 0,5 molar heptane solution). The quantity of Isopropanol thus added -was so measured that the weight ratio between the propylene homo polymerisate obtained in the first reactor and the propylene propylene co-polymerisate produced in the secound reactor reached the values indicated in the following table I. The quantity of the Isopropanol added can also be split in a manner that it is added partially in the intermediate container and partially in the second reactor. In the intermediate container the pressure was reduced respectively to 1 bar and maintained at that level for 30 seconds long and fmally by injecting a gas mixture, corresponding to the composition in the second reactor, increased to 30 bar. The polymer powder was transferred thereafter discontinuously from the intermediate container to the second reactor. There under a total pressure a temperature and a mean dwell-time corresponding to Table I, a compound made of propylene and ethylene was added to it for polymerization. The proportion of ethylene amounted to about 30 volume-% each. The weight ratio between the propylene homo polymer created in the first reactor, and the propylene co-polymer generated in the second reactor was controlled with the addition of Isopropanol and is indicated in Table I. The precise conditions of the Example 1, 2 and 3 according to the Invention, that means the values for pressure, temperature and dwell-time, the quantity of hydrogen used, as well as the quantity of the co-catalysts, the melt-flow rate (MFR) and the transfer quantity, that means the quantity of the polymer respectively obtained for both polymerization reactors are given in the following Table I. Table I contains further the weight ratio between the propylene homo polymer obtained in the first polymerization reactor [PP (I)] and the propylene ethylene co-polymer (EPRII) obtained in the second polymerization reactor. The proportion of the propylene-ethylene-co-polymerisate generated in the second reactor is calculated from the transfer and discharge quantities according to the following formula: The process was carried out in all the invention-related examples 1', 2' and 3' in two adjacent mixing autoclaves, equipped with a cantilevered spiral mixture, with an effective volume of 200 1 each. Both reactors were provided with a movable fixed bed made of fine particle propylene polymer. In the first polymerization reactor, the propylene was given in gas form and polymerized under a given dwell-time of 2,3 hours with the help of a Ziegler-Natta-Catalyst made of titanium containing solid components a), tri-ethyl aluminium and isobutyl isopropyle di-methoxy silane under a pressure and temperature as per Table IL In so doing, the dosage of the slid components was so measured that the charge/transfer from the first to the second polymerization reactor on an average corresponded to the values indicated in Table II. The dosage of these components was done together with the fresh propylene added for the purpose of pressure regulation. Similarly the following were also added to the reactor: tri-ethyl aluminium (in the form of a 1 molar heptane solution). For purpose of regulating the melting flow rate (as per ISO 1133) hydrogen was added, and the hydrogen concentration in the reaction gas was gas chromatographically controlled. Using short-time de-stressing of the reactor by means of an immersion tube successive polymer grains were removed from the reactor. The propylene homo polymer generated in the first reactor was thus discontinuously charged into the second reactor with the catalyst and together with the unconverted or not decomposed monomers, without de-stressing them in an intermediate container. There under a total pressure, a temperature and a mean dwell-time corresponding to Table II, a mixture of propylene and ethylene it is further polymerized. The proportion of ethylene accounted for 30 volume-% each. The weight ratio between the propylene homo polymer [PP (I)] generated in the first reactor and the propylene co-polymer [EPR (II)] generated in the second reactor is indicated in Table II. The following was similarly added in the second reactor; Isopropanol (in the form of a 0,5 molar heptane solution). The quantity added of Isopropanol was so measured that the weight ratio between PP (I) and EPR (II) was maintained as per figures given in Table 11. Propylene block polymer obtained in the comparison examples 1', 2' and 3' was finally extruded, after a peroxide mol mass reduction with the help of a 5 weight-% solution of di-tert-butyl peroxide in n-Heptane (Luperox ® 101 of M/s. Interox/Peroxid Chemie) in a double-worm extruder (ZSK 30, Worm 8 A of M/s. Werner & Pfleiderer). In this manner, their melt flow rate (MFR) could be significantly enhanced. The melt flow rates before (MFR II) and after the reduction of the mol mass reduction (MFR after reduction) are indicated in the following Table II. WE CLAIM: 1. A propylene block copolymer comprising from 50 to 80 wt% of a propylene homopolymer and from 20 to 50 wt% of a propylene copolymer containing from 10 to 70 wt% of a C2-C81-alkene other than propylene polymerized into it, obtainable by two-stage polymerization from the gas phase using a Ziegler-Natta catalyst system, where, in a first polymerization stage, propylene is polymerized at a pressiore of from 10 to 50 bar, a temperature from 50° to 100°C and a mean residence time of the reaction mixture of from 0.3 to 5 hours in the presence of at least 5.0 vol% of hydrogen in proportion to the total volume, and the propylene homopolymer obtained in the first polymerization stage is introduced along with the Ziegler-Natta catalyst system into an intermediate vessel, where it is firstly depressurized to less than 3.5 bar for from 0.1 to 5 minutes and maintained at a temperature of 10° to 80°C and the pressure in the intermediate vessel is raised again by 5 to 60 bar by the introduction under pressure of a gas mixture and the propylene homopolymer along with the Ziegler-Natta catalyst system is than transferred to a second polymerization stage where a mixture of propylene and a C2-C8 1-alkene is polymerized onto the propylene homopolymer at a pressure of from 10 to 50 bar, a temperature of from 50° to 100°C and a mean residence time of from 0.5 to 5 hours, and the weight ratio between the monomers reacted in the first and second polymerization stages is in the range of 4: 1 to 1: 1 said propylene black copolymer having a Melt Flow Rate ranging from2tol00g/10min. 2. The propylene block copolymer as claimed in claim 1, whose melt flow rate (MFR) at 230°C under a weight of 2.16 kg, measured in accordance to ISO 1133, satisfies the following equation (I): MFR >101.39 + 0.0787 * XS2 -5.4674 * XS (I) wherein XS is the proportion of the propylene copolymer, in percent based on the total propylene block copolymer. 3. The propylene block copolymer of claim 1 or 2, wherein the Ziegler-Natta catalyst system used comprises a titanium-containing solid component comprising, inter alia, a halogen-containing magnesium compound, an electron donor, and an inorganic oxide as support and also an aluminum compound and a further electron donor compound. 4. The propylene block copolymer of any of claims 1 to 3, wherein in the first polymerization stage propylene is polymerized at a pressure of 15 to 40 bar and at a temperature of 60 to 90°C. 5. The propylene block copolymer of any of claims 1 to 4, wherein 0.001 to 10 g, referred to the propylene homopolymer, of a C1-Cg alkanol are added per kg of the propylene homopolymer in the intermediate vessel. 6. The propylene block copolymer of any of claims 1 to 5, wherein after the depressurization the pressure in the intermediate container is raised again by from 10 to 40 bar by introducing a gas mixture under pressure. 7. The propylene block copolymer of any of claims 1 to 6, wherein in the second polymerization stage a mixture of propylene and a C2-C81-alkene is copolymerized at a pressure of 10 to 40 bar and at a temperature of 60° to 90°C. 8. A method for producing propylene block copolymers of any of claims 1 to 7, by two-stage polymerization from the gas phase using a Ziegler-Natta catalyst system, where in a first polymerization stage, propylene is polymerized at a pressure of 10 to 50 bar, a temperature of 50° to lOO°C and a mean residence time of the reaction mixture of 0.3 to 5 hours in the presence of at least 5.0 vol% of hydrogen in proportion to the total volume and the propylene homopolymer obtained in the first polymerization stage is introduced along with the Ziegler-Natta catalyst system into an intermediate vessel, where it is first depressurized for 0.1 to 5 minutes to less than 3.5 bar and held at a temperature of 10° to 80°C and the pressure in the intermediate vessel is subsequently raised again by 5 to 60 bar by the introduction under pressure of a gas mixture and the propylene homopolymer along with the Ziegler-Natta catalyst system is then transferred to a second polymerization stage where a mixture of propylene and a C2-C8 1-alkene is polymerized onto the propylene homopolymer at a pressure of 10 to 50 bar, a temperature of 500 to lOO°C and a mean residence time of 0.5 to 5 hours, and the weight ratio between the monomers reacted in the first and second polymerization stages is in the range of 4:1 to 1:1 said propylene block copolymer having a Melt Flow Rate ranging from 2 to 100 g/10 min.. 10. Films, fibers and molded articles comprising the propylene block copolymer as claimed in any of claims 1 to 7.

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Highly free-flowing Propylene block co-polymers Description:
The above-mentioned invention relates to a highly free-flowing propylene block copolymer, consisting of 50 to 80-weight % of a Pwith 10 to 70 weight % of a single polymerized Propylene of different C2-C8-Alk-ls, obtainable through two stage polymerization by means of a Ziegler-Natta-Catalyst System, from the gaseous phase. In so doing, in a first polymerization stage, under a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and a medium dwell time of the reaction compound of 0,3 to 5 hours in the presence of minimum 2 Volume %, with reference to the total volume of hydrogen, propylene is polymerized and then the propylene homo-polymer obtained in the first polymerization stage with the Ziegler-Natta-Catalyst system is collected in an intermediate Container. There, to start with it is de-stressed for a period of 0,01 to 5 minutes at less than 5 bar and maintained at a temperature of 10 to 80 °C, and finally through infusion of a gas compound the pressure in the intermediate Container is enhanced again by 5 to 60 bar and then the propylene homo-polymer obtained with the Ziegler-Natta-Catalyst system is transferred to a second polymerization stage. There, under a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and a mean dwell-time of 0,5 to 5 hours, the Propylene homo-polymer, a compound from Propylene and a C2-C8-Alk-ls, is polymerized and in so doing, the weight ratio between the Manomers converted in the first and the second polymerization stages is so measured that it lies in the range of 4:1 to 1:1.
Furthermore, the above invention relates to a process for manufacture of such highly free-flowing Propylene block co-polymers as well as their application as foils, yams or formed bodies.
Propylene-Ethylene-Block co-polymers, obtainable through polymerization under Ziegler-Natta-Catalyst system are already described in several patent documents (US-A 4 454 299, US-A 4 455 405, DE-A 3 827 565, DE-A 4 004 087). Such block copolymers are customarily manufactured according to a process in which, one starts with the polymerization of the gaseous propylene in a first polymerization stage and brings the resultant Propylene homo-polymers finally in a second polymerization stage, where a compound made of Propylene and Ethylene is additionally polymerized. The process is carried out customarily under enhanced pressure and in the presence of hydrogen as Mol mass regulator. The Propylene-Ethylene-Block Co-polymer thus obtained have often a good impact resistance and stiffness.
The Propylene Block Co-Polymers, which have a high degree of rubber proportion, that means, block co-polymers in which the co-polymer obtained in the second polymerization stage represents a higher share in the total Block co-polymer, can be achieved under the usual polymerization process only for relatively low melt-flow rates direct from the Reactor. This is attributable, among others, to the fact that the high

degree of hydrogen concentration necessary for regulating the Mol mass of the Block co-polymer is practically not realizable. Further, in the manufacture of Block copolymers, with high degree of rubber and a relatively high melt flow rate, one would often observe an undesirable deposit build-up in the second polymerization stage, connected with problems of Morphology of the products obtained. For these reasons, from the process point of view, it is very difficult to manufacture rubber-rich Propylene Block co-polymers which possess simultaneously a property of high impact resistance in conjunction with a high degree of flow, that means, their melt flow rates have high values.
A possibility to produce rubber-rich Propylene Block co-polymers, which possess a high degree of flow, exists in that, the rubber-rich Propylene block co-polymers are subjected to a subsequent Mol mass reduction with the help of organic peroxides, as a result of which, their melt flow rate and the resultant flowing property could be significantly enhanced. However, such a Mol mass reduction necessitates a relatively expensive additional process step. Furthermore, use of organic peroxides bring in its train a series of disadvantages such as, among others, enhanced emission of low molecular particles, odour nuisance, as well as (penalties in the form of) stiffness, heat forming resistance and softening behaviour.

organic aluminium compounds b) and Electron donor compounds c). In this fashion, the Propylene block co-polymers, as per the invention is accessible.
For the manufacture of titanium-containing solid components a) the Halogenide or alcoholates of the trivalent or quadrivalent titanium, whereby also titan-alcoxy halogen compounds or compounds of different titanium compounds can be considered. Preferably the titanium compounds, which contain chlorine as halogen are used. Similarly, the titan halogenides, which contain besides titanium only halogen, are preferred and in this context above all, the titanium chloride and especially Titan Tetrachloride.
The Titanium containing solid components a) includes preferably at least one halogen containing magnesium compound. What is understood herein as halogen are chlorine, Brom, Jod or Fluor, where Brom or especially Chlorine are preferred. The halogen-containing magnesium compounds are either directly applied during the manufacture of the titanium containing fixed components 'a' or generated during their manufacture. As magnesium compounds, which are suitable for manufacture of titanium-containing fixed components a), the magnesium halogenide occupies the first position such as particularly, Magnesium chloride or Magnesium bromide or Magnesium compounds, from which the Halogenide can be obtained generally, for instance, through decomposition or conversion with halogenisation materials such as magnesium alkyl, magnesium aryl, magnesium alkoxy or magnesium aryloxy compounds or Grignard compounds. Preferred examples for halogen-free compounds of the magnesium, which are suitable for manufacturing titanium-containing fixed components a) are n-Butyi Ethyl magnesium or n-Butyloctyl magnesium. Preferred halogenisation materials are chlorine or hydrochlorine. Also Titanium halogenide could however serve as halogenisation material.
Moreover, the titanium-containing fixed components a) contain electron donor compounds, for instance, mono or poly functional carbonic acid, carbonic acid anhydride or carbonic acid ester, further Keton, Ether, Alcohol, Lactone or phosphorous or silicon organic compounds.
Within the Titanium containing solid components, carbonic acid derivative and Phtal acid derivative of the general formula (II) are preferably used as Electron donor components, whereby, X and Y respectively represent a Chlorine or Brom atom or a Ci-C10-Alkoxy residue or jointly for oxygen in Anhydride function. Especially preferred electron donor compounds are: Phthal acid ester, where X and Y represent a Ci-Cg-Alkoxy residue. Examples for preferred phthal acid ester are Diethyl phthalat, Di-n-butyl phthalat, Di-iso-butyl phthalat, Di-n-pentyl phthalat, Di-n-hexyl phthalat, Di-n-heptyl phthalat, Di-n-octyl phthalat or Di-2-ethyl hexyl phthalat.
Other preferred electron donor compounds, within the titanium containing solid components are Diester of 3 or 4-branch or chain, where applicable substituted cycIoalkyl-1, 2-dicarbonic acid as well as Monoester of substituted Benzophenon-2-carbonic acid or substituted Benzophenon-2-carbonic acid. In these esters, alcanols

In the manufacture of titanium containing solid components a) , generally per Mol of the magnesium compound of 0,05 to 2,0 mol, preferably 0,2 to 1,0 mol of the Electron donor compounds are mixed.
Further, the titanium containing solid components a) can also contain inorganic oxides as carrier. Generally, a fine particle inorganic oxide is used as carrier, which has a mean particle diameter of 5 to 200 |am, preferably from 20 to 70 |im. What is meant by mean particle diameter is the volume based mean value of the grain size distribution, determined through the Couher-Counter-Analysis.
Ideally, the grains of the fine particle inorganic oxides consist of primary particles, which have a mean particle diameter of the primary particle of 1 to 20 \xm, especially 1 - 5 µm. The so-called primary particles relate to porous granular oxide particles, which have been generally obtained through grinding or a hydrogel of the inorganic oxide. It is also possible to filter the primary particles before their further processing.
Further, the inorganic oxide to be used preferably is also characterized thereby, that they have hollow space and/or channels with mean diameter of 0,1 to 20 µm, specially from 1 to 15 µm, whose macroscopic volume proportion on the total particle is in the range of 5 to 30%, preferably in the range of 10 to 30%.
The determination of the mean particle diameter of the primary particle as well as the macroscopic volume proportion of the hollow space and channels of the inorganic oxides is purposefully done through image analysis, with the help of the Scarming Electron Microscope (Raster Electron Microscope) and/or the Electron Probe Micro Analysis (Electron X-ray-Micro range analysis) on the grain surfaces and on grain cross sections of the inorganic oxide respectively. The exposures are evaluated and therefrom the mean particle diameter of the primary particle as well as the macroscopic volume portion of the hollow round and channels are determined. The image analysis is done preferably through transferring the electron microscopic Data in a Grey Value Binary Image; the digital evaluation is done using a suitable Computer Program, for instance, the Software-Packet Analysis of the company SIS.
The inorganic oxide to be used can be obtained for example through spray drying of the ground hygrogels, which for this purpose is mixed with water or an aliphatic alcohol. Such fine particle inorganic oxides are also obtainable in the market.
The fine particle inorganic oxides has also ordinarily a pore volume of 0,1 to 10 cm /g, ideally from 1,0 to 4,0 cm3/g and a specific surface of 10 to 1000 m2/g, ideally 100 to 500 m3/g, whereby the values referred to here are to be understood as those obtained

through Queck silver-Porosimetric as per DIN 66133 and through Nitrogen -Adsorption as per DIN 66131.
It is also possible to use an inorganic oxide, the pH-value of which, that means, the negative decadic Logarithm of the Proton Concentration, is in the range of 1 to 6,5 and preferably in the range of 2 to 6.
The oxides of Silicon, Aluminium, Titanium or one of the metals of I and/or II of tne Main Group of the Period System are to be considered as the inorganic oxides. Besides aluminium oxide or manganese oxide or sheet silicate, silicon oxide, (silicon gel) is used as a specially preferred oxide. Also, mixed oxides such as aluminium silicate or manganese silicate can also be used.
The inorganic oxides used as carriers contain water on their surface. This water is bound partly physically through adsorption and partly chemically in the form of Hydroxyl groups. Through thermal or chemical treatment, the water content of the inorganic oxide can be reduced or totally removed, where in respect of the chemical treatment, generally SiCl4, Chlorsilane or Aluminium alkyl are used as drying material. The water content of the suitable inorganic oxide should be from 0 to 6-weight %. An inorganic oxide in the form in which it is obtainable in the market is used v^thout any further treatment.
The magnesium compound and inorganic oxide within the titanium containing solid components a) should be preferably in such quantities that per Mol, preferably from 0,2 to 0,5 Mil, the compound of the Magnesium is found.
In the manufacture of the titanium-containing solid components a) the following groups generally come to be applied. Farther C1 to C6-Alcanol such as Methanol, Ethanol, n-Propanol, Isopropanol, n-ButanoI, tert-Butanol, Isobutanol, n-Hexanol, n-HeptanoI, n-Oktanol or 2-Ethyl hexanol or their compounds..
The titanium containing solid components can be manufactured according to known methods. Examples in this context are described, among others, in EP-A 45 975, EP-A 45v 977, EP-A 86 473, EP-A 171 200, GB-A 2 111 066 of the US-A 857 613 and the US-A 5 288 824. Ideally, it is manufactured based on the process described in DE-A 195 29 240.
Suitable aluminium compounds b) besides Tri-alkyl aluminium are also such compounds in which an alkoxy group is mixed by means of an aluminium group or through a halogen atom, for example through chlorine or Brom. The Alkyl groups can be identical or different from each other. Linear or branched alkyl groups come into consideration. Preferably, Tri-alkyl aluminium compounds are used, whose alkyl groupshave respectively 1 to 8 C-atom, for instance, Tri-methyl aluminium, Tri-ethyl aluminium, Tri-iso-butylalmimium, Trioctyl aluminium or Methyl Diethyl aluminium or compounds thereof.

Generally, besides the aluminium compound b) one also uses as additional catalyst electron donor compounds c) such as Mono-functional or Poly-functional carbonic acids, carbon acid anhydride or carbonic acid ester, farther Ketone, Ether, Alcohol, Lactone, as well as phosphorous and silicon organic compounds where the Electron Donor compounds c) could be identical or different from the Electron donor Compounds used for the manufacture of the titanium-containing solid components a). Preferred Electron donor compounds are silicon organic compounds of the general formula (I)

Among these compounds the following are to be preferred
Dimethoxydiisopropylsilan, Dimethoxyisobutylisopropylislan,
Dimethoxydiisobutylsilan, Dmethoxydicyclopentylsilan, Dimethoxyisopropyl-tert. -butylsilan,Diemethoxyisobutyl-sek.-butylsilan and Dimethoxyisopropyl-sek.-butylsilan.
Preferably the co-catalysts b) and c) are applied in such quantities that the atom ratio between aluminium from the aluminium compounds b) and titanium from the titanium-containing solid components a) is between 10:1 to 800:1, especially between 20: 1 to 200:1 and the Mol ratio between the aluminium compound b) and the Electron donor compound c) from 1:1 to 250:1, especially from 10:1 to 80:1
The titanium containing solid components a), the aluminium compound b) and the generally used Electron donor compounds c) together build the Ziegler-Natta-Catalyst System, The Catalyst substances b) and c) could be added to the Polymerization reactor together with the Titanium-containing solid components c) as a mixture or even in optional sequence individually.
The process for manufacture of the invention-based highly free - flowing Propylene Block Co-polymers is carried out in two subsequently operated polymerization stages that means, in a Reactor cascade, in the gas phase. The customary Reactors used for the Polymerization C2-C8-Alk Is can be used.. Suitable Reactors are, among others, continuously operated mixing boiler, loop Reactors or fluidized bed Reactors. The size of the Reactors is of no less importance for the Invention-based process. It depends on the yield, which must be achieved in the Reactor or in the individual Reactor Zone.

Specially fluidized Bed Reactors as well as horizontally or vertically mixing powder Reactors are used. The Reaction Bed in the process as per the invention consists of in general, the Polymer C2-C8-Alk-ls, which is polymerized in the respective Reactor.
In a specially preferred design form, the process used for the manufacture of the Invention-based Propylene Block Co-polymer, the process is carried out in a Cascade of subsequently operated Reactors in which the powder formed reaction bed is kept in motion through a vertical Mixer for which purpose the so-called Cantilevered spiral mixture is especially suitable. Such Mixers are known, among others, from EP-B 000 512 and the EP-B 031 417. They exemplify themselves by the fact that they distribute the powder formed Reaction bed very homogenously. Examples for such powder formed Reaction bed are described in EP-B 038 478. Preferably, the Reaction cascade consists of two subsequently operated boiler-formed reactors with a Mixer and with a capacity of 0,1 to 100m3 for example 12,5 25, 50 or 75 m3
During the polymerization for producing the invention-based Propylene block copolymer, its Mol mass can be controlled and set through the customary chain transfer agents used in Polymerization technology, for example through Hydrogen. Besides such agents, also so-called Reactors, that means, compounds, which influence the catalyst activity, or even anti-static properties can be used. The latter compounds prevent the build-up of deposit on the reactor walls through Electro Static Descaling.
In the first polymerization stage, for products of the invention-based Propylene Block Co-Polymers under customary re-action conditions: Propylene is polymerized under a pressure of 10 to 50 bar, especially from 15 to 40 bar, a temperature of 50 to 100°C, especially 60 to 90 °C and under a mean dwell-time of 0,3 to 5 hours, preferably from 0,8 to 4 hours. For controlling the Mol mass of the Propylene homo-polymers in the first polymerization stage in the presence of at least 2,0 Volume % of hydrogen, the polymerization is done preferably with minimum 5,0 volume %, based on the total mix applicable for this polymerization stage The Propylene homo-polymers obtained in the first polymerization stage represents the so-called Matrix of the invention-based Propylene Block Co-polymers and possesses a Poly Dispersity Index (PI) of minimum 2,8, preferably at least 3,0.
Subsequently, the Propylene homo-polymer obtained in the first Polymerization stage, using the Ziegler-Natta-Catalyst system, is removed from the first Polymerizatin stage and transferred in an intermediate container. The Reactors or customarily used Containers for the Polymerization C2-C8-Alk-ls are used as intermediate Coisainers. Suitable intermediate containers are, for example, cylindrical containers, mixing containers or even cyclones.
Propylene homo-polymer transferred from the first Polymerization stage, together with the Ziegler-Natta-Catalyst system is de-stressed to start with for a duration of 0,01 to5 minutes, preferably 0,1 to 4 minutes, at less than 5 bar, preferably at less than 3,5 bar. During this time, one could also add to the Propylene homo-polymer, homo-polymer also 0,001g tolO g, preferably 0,001 g to 1,0 g of a Cl-C8-Alcanol per kg of the

Propylene for better control of the subsequent Polymerization steps. For this purpose, Isopropanol, as also Ethanol or Glycol are especially suitable. The intermediate Container is maintained at a temperature of 10 to 20 °C, preferably between 20 to 70 °C, subsequently through injection of a gas mixture from the Monomers used, that means, Propylene as well as the C2-C8-Alk-ls, the pressure in the intermediate Container is enhanced again by 5 to 60 bar, preferably by 10 to 15 bar. In the intermediate Container, the Reaction mixture can also be converted using the customary anti-static substances, for example, Poly glycol ether of fatty alcohols, fatty acids and Alkyl phenol, Alkyl sulphate and alkyl phosphate as well as Quarter Ammonium compounds.
Thereafter, the Propylene homo-polymers together with the Ziegler-Natta-Catalyst system is removed from the Intermediate Container and brought into the second Polymerization stage. In the second polymerization stage, the Propylene homo-polymer is additionally polymerized under a pressure of 10 to 50 bar, preferably 10 to 40 bar, with a temperature of 50 to lOO°C, preferably 60 to 90°C and a mean dwell-time of 0,5 to 5 hours, preferably from 0,8 to 4 hours, a mixture out of Propylene and a C2-C8-Alkls, In this process, the weight ratio between the Monomer obtained in the first and second polymerization stages is so measured that it lies in the range of 4:1 to 1:1, preferably in the range of 4:1 to 1,5:1. Similar to the case of the Intermediate Container, one could also add in the second polymerization stage, 0,001 g to 10 g, preferably 0,005 g to 0.5 g of a C1-C8-Alcanols. For this purpose, Iso-propanol, Glycol or also Ethanol recommend temselves as the most optimum. Suitable co-monomers of the Propylene in the second polymerization stage are, among others, Ethylene and But-Is. The share of this or these Co-monomers of the Propylene on the suitable gas mixture in the second polyTnerization stage should be preferably 15 to 60 Volume %, preferably 20 to 50 Volume %.
The Propylene block co-polymer obtained in this manner according to the invention, has a Melt Flow Rate (MFR) as specified in ISO 1133, under 230T and a weight of 2,16 kg and would fit the following notation: (I)
(I)MFR> 101,39 + 0,0787 ♦ XS2 - 5,4674*XS
where XS represents the share of the propylene co-polymer in percentage developed in the second polymerization stage, related to the total Propylene Block Co-Polymers.
The Melt Flow Rate of the propylene block co-polymers obtained lie in general in the range of 2 to 100 g/10 min., preferably in the range of 5 to 80 g/10 min., respectively at 230°C and under a weight of 2,16 kg. The Melt Flow Rate corresponds in this context to the quantity of polymer, which is extruded within a period of 10 minutes from the testing device Normed according to ISO 1133 under a temperature of 230° C and under a weight of 2,16 kg. The Invention-based Propylene block co-polymers are manufactured without Mol mass reduction based on peroxide.

The Invention based Propylene block co-polymers exemplify themselves, among others, through a high degree of flow capability, that means through an enhanced melt flow rate under simultaneous rubber proportion. This denotes that the proportion of the propylene block co-polymer in the total propylene block co-polymer is more. Further, the invention-based propylene block co-polymers are characterized through a high degree of impact resistance and stiffness as well as through a good heat-forming resistance and flow capability in injection moulding (spiral flow property). They contain with all this, only relatively less low molecular substances, as for instance, n-Hepten or tert.Butanol.
Similarly the invention-based process can be carried out in the customary reaction of the plastic technology in a simple manner without the need for having the propylene block co-polymers subjected to a subsequent reduction of Mol mass.
The invention based propylene block co-polymers are suitable, above all for manufacture of foils, fibres and formed bodies.
Examples:
In all the invention based examples 1, 2 and 3 as well as the comparative examples A, B and C, Zieger-Natta-Catalyst system was applied, which encompasses the titanium containing solid material a) manufactured according to the following process.
In a first stage a fine particle silica gel, which has a mean particle dia of about 30 jim, a pore volume of 1,5 cm3/g and a specific surface of 260 m /g is added to a solution of n-Butyl Octyl Magnesium in n-Heptane, where per Mol Si02 0,3 mol of the magnesium compound was added. The fine particle silica gel was additionally characterized through a mean particle size of the primary particle of 3-5µm and through hollow space and canals with a dia of 3-5 µm, where the macroscopic volume proportion of the hollow space and canals on the total particle was about 15%. The solution was stirred for 45 minutes under 95°C, thereafter cooled to 20°C, after which the 10-time molar quantity, based on the magnesium organic compound in hydrogen chloride, was introduced. After 60 minutes, the reaction product was added under constant stirring with 3 mol ethanol per mol magnesium was added. This mixture was stirred 0,5 hours under 80°C and subsequently was added with 7,2 mol Titanium Tetrachloride and 0,5 mol Di-n-Butyl Phthalate each respectively based on 1 mol magnesium. Finally the compound was stirred for one hour under 100°C, and the solid stuff thus obtained filtered and washed with ethyl benzene several times.
The solid product obtained therefrom is extracted for three hours under 125°C with a lO-volume-% solution of titanium tetrachloride in ethyl benzene. Thereafter the solid product was separated through filtration from the extraction material and washed with n-Heptane so long till the extraction material had only of 0,3 weight-% of titanium tetrachloride.
The titanium containing solid components a) contain:

3,5weight-%Ti 7,4 weight-% Mg 28,2 weight-% CI
Besides the titanium containing solid components a) Tri-ethyl Aluminium and Di-methoxy Isobutyl Isopropylsilan were used as co-catalysts analogous to the gauge of US-A 4 857 613 and the US-A 5 288 824.
Example 1, 2 and 3
The process was carried out in all invention-related examples 1, 2 and 3 in two adjacent mixing auto claves, equipped with a cantilevered spiral mixture, with a rated volume of 200 1 each. Both reactors were provided with a movable fixed bed made of fine particle propylene polymer.
In the first polymerization reactor, the propylene was added in gas form and under a medium dwell-time, under pressure and a temperature according to table 1 was polymerized. The Ziegler-Natta-Catalyst System deployed for this purpose consisted of the titanium containing solid components a) as well as tri-ethyl alummium and isobutyl isopropyl di-methoxy-silane as catalysts. In this process the dosage of the solid components was so measured that the transfer from the first into the second polymerization reactor in mean free time corresponded to the values indicated in Table 1. The dosage of these components was done with the fresh propylene added for the purpose of pressure regulation. Similarly the following were also added into the reactor: as further catalyst substances tri-ethyl aluminium (in the form of a 1 molar heptane solution) in a quantity of 60 to maximum 105 ml/hour, and Isobutyl Isopropyl di-methoxy-silane (in the form of a 0,125 molar heptane solution) in a quantity of 70 to maximum 120 ml/hour. For regulating the melt flow rate (as per ISO 1133) hydrogen was added, and the hydrogen concentration in the reaction gas was gas chromatographically controlled.
By means of short-time recess of the reactors through an inunersion tube, successive polymer substance was removed firom the reactor. The propylene homo-polymer obtained in the first reactor was thereby discontinuously transferred with the catalysts into an intermediate container and converted there with Isopropanol (in the form of 0,5 molar heptane solution). The quantity of Isopropanol thus added -was so measured that the weight ratio between the propylene homo polymerisate obtained in the first reactor and the propylene propylene co-polymerisate produced in the secound reactor reached the values indicated in the following table I. The quantity of the Isopropanol added can also be split in a manner that it is added partially in the intermediate container and partially in the second reactor. In the intermediate container the pressure was reduced respectively to 1 bar and maintained at that level for 30 seconds long and fmally by injecting a gas mixture, corresponding to the composition in the second reactor, increased to 30 bar.

The polymer powder was transferred thereafter discontinuously from the intermediate container to the second reactor. There under a total pressure a temperature and a mean dwell-time corresponding to Table I, a compound made of propylene and ethylene was added to it for polymerization. The proportion of ethylene amounted to about 30 volume-% each. The weight ratio between the propylene homo polymer created in the first reactor, and the propylene co-polymer generated in the second reactor was controlled with the addition of Isopropanol and is indicated in Table I.
The precise conditions of the Example 1, 2 and 3 according to the Invention, that means the values for pressure, temperature and dwell-time, the quantity of hydrogen used, as well as the quantity of the co-catalysts, the melt-flow rate (MFR) and the transfer quantity, that means the quantity of the polymer respectively obtained for both polymerization reactors are given in the following Table I. Table I contains further the weight ratio between the propylene homo polymer obtained in the first polymerization reactor [PP (I)] and the propylene ethylene co-polymer (EPRII) obtained in the second polymerization reactor.
The proportion of the propylene-ethylene-co-polymerisate generated in the second reactor is calculated from the transfer and discharge quantities according to the following formula:

The process was carried out in all the invention-related examples 1', 2' and 3' in two adjacent mixing autoclaves, equipped with a cantilevered spiral mixture, with an effective volume of 200 1 each. Both reactors were provided with a movable fixed bed made of fine particle propylene polymer.
In the first polymerization reactor, the propylene was given in gas form and polymerized under a given dwell-time of 2,3 hours with the help of a Ziegler-Natta-Catalyst made of titanium containing solid components a), tri-ethyl aluminium and isobutyl isopropyle di-methoxy silane under a pressure and temperature as per Table IL In so doing, the dosage of the slid components was so measured that the charge/transfer from the first to the second polymerization reactor on an average corresponded to the values indicated in Table II. The dosage of these components was done together with the fresh propylene added for the purpose of pressure regulation. Similarly the following were also added to the reactor: tri-ethyl aluminium (in the form of a 1 molar heptane solution). For purpose of regulating the melting flow rate (as per ISO 1133) hydrogen was added, and the hydrogen concentration in the reaction gas was gas chromatographically controlled.
Using short-time de-stressing of the reactor by means of an immersion tube successive polymer grains were removed from the reactor. The propylene homo polymer generated in the first reactor was thus discontinuously charged into the second reactor with the catalyst and together with the unconverted or not decomposed monomers, without de-stressing them in an intermediate container.
There under a total pressure, a temperature and a mean dwell-time corresponding to Table II, a mixture of propylene and ethylene it is further polymerized. The proportion of ethylene accounted for 30 volume-% each. The weight ratio between the propylene homo polymer [PP (I)] generated in the first reactor and the propylene co-polymer [EPR (II)] generated in the second reactor is indicated in Table II. The following was similarly added in the second reactor; Isopropanol (in the form of a 0,5 molar heptane solution). The quantity added of Isopropanol was so measured that the weight ratio between PP (I) and EPR (II) was maintained as per figures given in Table 11.

Propylene block polymer obtained in the comparison examples 1', 2' and 3' was finally extruded, after a peroxide mol mass reduction with the help of a 5 weight-% solution of di-tert-butyl peroxide in n-Heptane (Luperox ® 101 of M/s. Interox/Peroxid Chemie) in a double-worm extruder (ZSK 30, Worm 8 A of M/s. Werner & Pfleiderer). In this manner, their melt flow rate (MFR) could be significantly enhanced. The melt flow rates before (MFR II) and after the reduction of the mol mass reduction (MFR after reduction) are indicated in the following Table II.

Highly free-flowing Propylene block co-polymers Description:
The above-mentioned invention relates to a highly free-flowing propylene block copolymer, consisting of 50 to 80-weight % of a Pwith 10 to 70 weight % of a single polymerized Propylene of different C2-C8-Alk-ls, obtainable through two stage polymerization by means of a Ziegler-Natta-Catalyst System, from the gaseous phase. In so doing, in a first polymerization stage, under a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and a medium dwell time of the reaction compound of 0,3 to 5 hours in the presence of minimum 2 Volume %, with reference to the total volume of hydrogen, propylene is polymerized and then the propylene homo-polymer obtained in the first polymerization stage with the Ziegler-Natta-Catalyst system is collected in an intermediate Container. There, to start with it is de-stressed for a period of 0,01 to 5 minutes at less than 5 bar and maintained at a temperature of 10 to 80 °C, and finally through infusion of a gas compound the pressure in the intermediate Container is enhanced again by 5 to 60 bar and then the propylene homo-polymer obtained with the Ziegler-Natta-Catalyst system is transferred to a second polymerization stage. There, under a pressure of 10 to 50 bar, a temperature of 50 to 100 °C and a mean dwell-time of 0,5 to 5 hours, the Propylene homo-polymer, a compound from Propylene and a C2-C8-Alk-ls, is polymerized and in so doing, the weight ratio between the Manomers converted in the first and the second polymerization stages is so measured that it lies in the range of 4:1 to 1:1.
Furthermore, the above invention relates to a process for manufacture of such highly free-flowing Propylene block co-polymers as well as their application as foils, yams or formed bodies.
Propylene-Ethylene-Block co-polymers, obtainable through polymerization under Ziegler-Natta-Catalyst system are already described in several patent documents (US-A 4 454 299, US-A 4 455 405, DE-A 3 827 565, DE-A 4 004 087). Such block copolymers are customarily manufactured according to a process in which, one starts with the polymerization of the gaseous propylene in a first polymerization stage and brings the resultant Propylene homo-polymers finally in a second polymerization stage, where a compound made of Propylene and Ethylene is additionally polymerized. The process is carried out customarily under enhanced pressure and in the presence of hydrogen as Mol mass regulator. The Propylene-Ethylene-Block Co-polymer thus obtained have often a good impact resistance and stiffness.
The Propylene Block Co-Polymers, which have a high degree of rubber proportion, that means, block co-polymers in which the co-polymer obtained in the second polymerization stage represents a higher share in the total Block co-polymer, can be achieved under the usual polymerization process only for relatively low melt-flow rates direct from the Reactor. This is attributable, among others, to the fact that the high

degree of hydrogen concentration necessary for regulating the Mol mass of the Block co-polymer is practically not realizable. Further, in the manufacture of Block copolymers, with high degree of rubber and a relatively high melt flow rate, one would often observe an undesirable deposit build-up in the second polymerization stage, connected with problems of Morphology of the products obtained. For these reasons, from the process point of view, it is very difficult to manufacture rubber-rich Propylene Block co-polymers which possess simultaneously a property of high impact resistance in conjunction with a high degree of flow, that means, their melt flow rates have high values.
A possibility to produce rubber-rich Propylene Block co-polymers, which possess a high degree of flow, exists in that, the rubber-rich Propylene block co-polymers are subjected to a subsequent Mol mass reduction with the help of organic peroxides, as a result of which, their melt flow rate and the resultant flowing property could be significantly enhanced. However, such a Mol mass reduction necessitates a relatively expensive additional process step. Furthermore, use of organic peroxides bring in its train a series of disadvantages such as, among others, enhanced emission of low molecular particles, odour nuisance, as well as (penalties in the form of) stiffness, heat forming resistance and softening behaviour.

organic aluminium compounds b) and Electron donor compounds c). In this fashion, the Propylene block co-polymers, as per the invention is accessible.
For the manufacture of titanium-containing solid components a) the Halogenide or alcoholates of the trivalent or quadrivalent titanium, whereby also titan-alcoxy halogen compounds or compounds of different titanium compounds can be considered. Preferably the titanium compounds, which contain chlorine as halogen are used. Similarly, the titan halogenides, which contain besides titanium only halogen, are preferred and in this context above all, the titanium chloride and especially Titan Tetrachloride.
The Titanium containing solid components a) includes preferably at least one halogen containing magnesium compound. What is understood herein as halogen are chlorine, Brom, Jod or Fluor, where Brom or especially Chlorine are preferred. The halogen-containing magnesium compounds are either directly applied during the manufacture of the titanium containing fixed components 'a' or generated during their manufacture. As magnesium compounds, which are suitable for manufacture of titanium-containing fixed components a), the magnesium halogenide occupies the first position such as particularly, Magnesium chloride or Magnesium bromide or Magnesium compounds, from which the Halogenide can be obtained generally, for instance, through decomposition or conversion with halogenisation materials such as magnesium alkyl, magnesium aryl, magnesium alkoxy or magnesium aryloxy compounds or Grignard compounds. Preferred examples for halogen-free compounds of the magnesium, which are suitable for manufacturing titanium-containing fixed components a) are n-Butyi Ethyl magnesium or n-Butyloctyl magnesium. Preferred halogenisation materials are chlorine or hydrochlorine. Also Titanium halogenide could however serve as halogenisation material.
Moreover, the titanium-containing fixed components a) contain electron donor compounds, for instance, mono or poly functional carbonic acid, carbonic acid anhydride or carbonic acid ester, further Keton, Ether, Alcohol, Lactone or phosphorous or silicon organic compounds.
Within the Titanium containing solid components, carbonic acid derivative and Phtal acid derivative of the general formula (II) are preferably used as Electron donor components, whereby, X and Y respectively represent a Chlorine or Brom atom or a Ci-C10-Alkoxy residue or jointly for oxygen in Anhydride function. Especially preferred electron donor compounds are: Phthal acid ester, where X and Y represent a Ci-Cg-Alkoxy residue. Examples for preferred phthal acid ester are Diethyl phthalat, Di-n-butyl phthalat, Di-iso-butyl phthalat, Di-n-pentyl phthalat, Di-n-hexyl phthalat, Di-n-heptyl phthalat, Di-n-octyl phthalat or Di-2-ethyl hexyl phthalat.
Other preferred electron donor compounds, within the titanium containing solid components are Diester of 3 or 4-branch or chain, where applicable substituted cycIoalkyl-1, 2-dicarbonic acid as well as Monoester of substituted Benzophenon-2-carbonic acid or substituted Benzophenon-2-carbonic acid. In these esters, alcanols

In the manufacture of titanium containing solid components a) , generally per Mol of the magnesium compound of 0,05 to 2,0 mol, preferably 0,2 to 1,0 mol of the Electron donor compounds are mixed.
Further, the titanium containing solid components a) can also contain inorganic oxides as carrier. Generally, a fine particle inorganic oxide is used as carrier, which has a mean particle diameter of 5 to 200 |am, preferably from 20 to 70 |im. What is meant by mean particle diameter is the volume based mean value of the grain size distribution, determined through the Couher-Counter-Analysis.
Ideally, the grains of the fine particle inorganic oxides consist of primary particles, which have a mean particle diameter of the primary particle of 1 to 20 \xm, especially 1 - 5 µm. The so-called primary particles relate to porous granular oxide particles, which have been generally obtained through grinding or a hydrogel of the inorganic oxide. It is also possible to filter the primary particles before their further processing.
Further, the inorganic oxide to be used preferably is also characterized thereby, that they have hollow space and/or channels with mean diameter of 0,1 to 20 µm, specially from 1 to 15 µm, whose macroscopic volume proportion on the total particle is in the range of 5 to 30%, preferably in the range of 10 to 30%.
The determination of the mean particle diameter of the primary particle as well as the macroscopic volume proportion of the hollow space and channels of the inorganic oxides is purposefully done through image analysis, with the help of the Scarming Electron Microscope (Raster Electron Microscope) and/or the Electron Probe Micro Analysis (Electron X-ray-Micro range analysis) on the grain surfaces and on grain cross sections of the inorganic oxide respectively. The exposures are evaluated and therefrom the mean particle diameter of the primary particle as well as the macroscopic volume portion of the hollow round and channels are determined. The image analysis is done preferably through transferring the electron microscopic Data in a Grey Value Binary Image; the digital evaluation is done using a suitable Computer Program, for instance, the Software-Packet Analysis of the company SIS.
The inorganic oxide to be used can be obtained for example through spray drying of the ground hygrogels, which for this purpose is mixed with water or an aliphatic alcohol. Such fine particle inorganic oxides are also obtainable in the market.
The fine particle inorganic oxides has also ordinarily a pore volume of 0,1 to 10 cm /g, ideally from 1,0 to 4,0 cm3/g and a specific surface of 10 to 1000 m2/g, ideally 100 to 500 m3/g, whereby the values referred to here are to be understood as those obtained

through Queck silver-Porosimetric as per DIN 66133 and through Nitrogen -Adsorption as per DIN 66131.
It is also possible to use an inorganic oxide, the pH-value of which, that means, the negative decadic Logarithm of the Proton Concentration, is in the range of 1 to 6,5 and preferably in the range of 2 to 6.
The oxides of Silicon, Aluminium, Titanium or one of the metals of I and/or II of tne Main Group of the Period System are to be considered as the inorganic oxides. Besides aluminium oxide or manganese oxide or sheet silicate, silicon oxide, (silicon gel) is used as a specially preferred oxide. Also, mixed oxides such as aluminium silicate or manganese silicate can also be used.
The inorganic oxides used as carriers contain water on their surface. This water is bound partly physically through adsorption and partly chemically in the form of Hydroxyl groups. Through thermal or chemical treatment, the water content of the inorganic oxide can be reduced or totally removed, where in respect of the chemical treatment, generally SiCl4, Chlorsilane or Aluminium alkyl are used as drying material. The water content of the suitable inorganic oxide should be from 0 to 6-weight %. An inorganic oxide in the form in which it is obtainable in the market is used v^thout any further treatment.
The magnesium compound and inorganic oxide within the titanium containing solid components a) should be preferably in such quantities that per Mol, preferably from 0,2 to 0,5 Mil, the compound of the Magnesium is found.
In the manufacture of the titanium-containing solid components a) the following groups generally come to be applied. Farther C1 to C6-Alcanol such as Methanol, Ethanol, n-Propanol, Isopropanol, n-ButanoI, tert-Butanol, Isobutanol, n-Hexanol, n-HeptanoI, n-Oktanol or 2-Ethyl hexanol or their compounds..
The titanium containing solid components can be manufactured according to known methods. Examples in this context are described, among others, in EP-A 45 975, EP-A 45v 977, EP-A 86 473, EP-A 171 200, GB-A 2 111 066 of the US-A 857 613 and the US-A 5 288 824. Ideally, it is manufactured based on the process described in DE-A 195 29 240.
Suitable aluminium compounds b) besides Tri-alkyl aluminium are also such compounds in which an alkoxy group is mixed by means of an aluminium group or through a halogen atom, for example through chlorine or Brom. The Alkyl groups can be identical or different from each other. Linear or branched alkyl groups come into consideration. Preferably, Tri-alkyl aluminium compounds are used, whose alkyl groupshave respectively 1 to 8 C-atom, for instance, Tri-methyl aluminium, Tri-ethyl aluminium, Tri-iso-butylalmimium, Trioctyl aluminium or Methyl Diethyl aluminium or compounds thereof.

Generally, besides the aluminium compound b) one also uses as additional catalyst electron donor compounds c) such as Mono-functional or Poly-functional carbonic acids, carbon acid anhydride or carbonic acid ester, farther Ketone, Ether, Alcohol, Lactone, as well as phosphorous and silicon organic compounds where the Electron Donor compounds c) could be identical or different from the Electron donor Compounds used for the manufacture of the titanium-containing solid components a). Preferred Electron donor compounds are silicon organic compounds of the general formula (I)

Among these compounds the following are to be preferred
Dimethoxydiisopropylsilan, Dimethoxyisobutylisopropylislan,
Dimethoxydiisobutylsilan, Dmethoxydicyclopentylsilan, Dimethoxyisopropyl-tert. -butylsilan,Diemethoxyisobutyl-sek.-butylsilan and Dimethoxyisopropyl-sek.-butylsilan.
Preferably the co-catalysts b) and c) are applied in such quantities that the atom ratio between aluminium from the aluminium compounds b) and titanium from the titanium-containing solid components a) is between 10:1 to 800:1, especially between 20: 1 to 200:1 and the Mol ratio between the aluminium compound b) and the Electron donor compound c) from 1:1 to 250:1, especially from 10:1 to 80:1
The titanium containing solid components a), the aluminium compound b) and the generally used Electron donor compounds c) together build the Ziegler-Natta-Catalyst System, The Catalyst substances b) and c) could be added to the Polymerization reactor together with the Titanium-containing solid components c) as a mixture or even in optional sequence individually.
The process for manufacture of the invention-based highly free - flowing Propylene Block Co-polymers is carried out in two subsequently operated polymerization stages that means, in a Reactor cascade, in the gas phase. The customary Reactors used for the Polymerization C2-C8-Alk Is can be used.. Suitable Reactors are, among others, continuously operated mixing boiler, loop Reactors or fluidized bed Reactors. The size of the Reactors is of no less importance for the Invention-based process. It depends on the yield, which must be achieved in the Reactor or in the individual Reactor Zone.

Specially fluidized Bed Reactors as well as horizontally or vertically mixing powder Reactors are used. The Reaction Bed in the process as per the invention consists of in general, the Polymer C2-C8-Alk-ls, which is polymerized in the respective Reactor.
In a specially preferred design form, the process used for the manufacture of the Invention-based Propylene Block Co-polymer, the process is carried out in a Cascade of subsequently operated Reactors in which the powder formed reaction bed is kept in motion through a vertical Mixer for which purpose the so-called Cantilevered spiral mixture is especially suitable. Such Mixers are known, among others, from EP-B 000 512 and the EP-B 031 417. They exemplify themselves by the fact that they distribute the powder formed Reaction bed very homogenously. Examples for such powder formed Reaction bed are described in EP-B 038 478. Preferably, the Reaction cascade consists of two subsequently operated boiler-formed reactors with a Mixer and with a capacity of 0,1 to 100m3 for example 12,5 25, 50 or 75 m3
During the polymerization for producing the invention-based Propylene block copolymer, its Mol mass can be controlled and set through the customary chain transfer agents used in Polymerization technology, for example through Hydrogen. Besides such agents, also so-called Reactors, that means, compounds, which influence the catalyst activity, or even anti-static properties can be used. The latter compounds prevent the build-up of deposit on the reactor walls through Electro Static Descaling.
In the first polymerization stage, for products of the invention-based Propylene Block Co-Polymers under customary re-action conditions: Propylene is polymerized under a pressure of 10 to 50 bar, especially from 15 to 40 bar, a temperature of 50 to 100°C, especially 60 to 90 °C and under a mean dwell-time of 0,3 to 5 hours, preferably from 0,8 to 4 hours. For controlling the Mol mass of the Propylene homo-polymers in the first polymerization stage in the presence of at least 2,0 Volume % of hydrogen, the polymerization is done preferably with minimum 5,0 volume %, based on the total mix applicable for this polymerization stage The Propylene homo-polymers obtained in the first polymerization stage represents the so-called Matrix of the invention-based Propylene Block Co-polymers and possesses a Poly Dispersity Index (PI) of minimum 2,8, preferably at least 3,0.
Subsequently, the Propylene homo-polymer obtained in the first Polymerization stage, using the Ziegler-Natta-Catalyst system, is removed from the first Polymerizatin stage and transferred in an intermediate container. The Reactors or customarily used Containers for the Polymerization C2-C8-Alk-ls are used as intermediate Coisainers. Suitable intermediate containers are, for example, cylindrical containers, mixing containers or even cyclones.
Propylene homo-polymer transferred from the first Polymerization stage, together with the Ziegler-Natta-Catalyst system is de-stressed to start with for a duration of 0,01 to5 minutes, preferably 0,1 to 4 minutes, at less than 5 bar, preferably at less than 3,5 bar. During this time, one could also add to the Propylene homo-polymer, homo-polymer also 0,001g tolO g, preferably 0,001 g to 1,0 g of a Cl-C8-Alcanol per kg of the

Propylene for better control of the subsequent Polymerization steps. For this purpose, Isopropanol, as also Ethanol or Glycol are especially suitable. The intermediate Container is maintained at a temperature of 10 to 20 °C, preferably between 20 to 70 °C, subsequently through injection of a gas mixture from the Monomers used, that means, Propylene as well as the C2-C8-Alk-ls, the pressure in the intermediate Container is enhanced again by 5 to 60 bar, preferably by 10 to 15 bar. In the intermediate Container, the Reaction mixture can also be converted using the customary anti-static substances, for example, Poly glycol ether of fatty alcohols, fatty acids and Alkyl phenol, Alkyl sulphate and alkyl phosphate as well as Quarter Ammonium compounds.
Thereafter, the Propylene homo-polymers together with the Ziegler-Natta-Catalyst system is removed from the Intermediate Container and brought into the second Polymerization stage. In the second polymerization stage, the Propylene homo-polymer is additionally polymerized under a pressure of 10 to 50 bar, preferably 10 to 40 bar, with a temperature of 50 to lOO°C, preferably 60 to 90°C and a mean dwell-time of 0,5 to 5 hours, preferably from 0,8 to 4 hours, a mixture out of Propylene and a C2-C8-Alkls, In this process, the weight ratio between the Monomer obtained in the first and second polymerization stages is so measured that it lies in the range of 4:1 to 1:1, preferably in the range of 4:1 to 1,5:1. Similar to the case of the Intermediate Container, one could also add in the second polymerization stage, 0,001 g to 10 g, preferably 0,005 g to 0.5 g of a C1-C8-Alcanols. For this purpose, Iso-propanol, Glycol or also Ethanol recommend temselves as the most optimum. Suitable co-monomers of the Propylene in the second polymerization stage are, among others, Ethylene and But-Is. The share of this or these Co-monomers of the Propylene on the suitable gas mixture in the second polyTnerization stage should be preferably 15 to 60 Volume %, preferably 20 to 50 Volume %.
The Propylene block co-polymer obtained in this manner according to the invention, has a Melt Flow Rate (MFR) as specified in ISO 1133, under 230T and a weight of 2,16 kg and would fit the following notation: (I)
(I)MFR> 101,39 + 0,0787 ♦ XS2 - 5,4674*XS
where XS represents the share of the propylene co-polymer in percentage developed in the second polymerization stage, related to the total Propylene Block Co-Polymers.
The Melt Flow Rate of the propylene block co-polymers obtained lie in general in the range of 2 to 100 g/10 min., preferably in the range of 5 to 80 g/10 min., respectively at 230°C and under a weight of 2,16 kg. The Melt Flow Rate corresponds in this context to the quantity of polymer, which is extruded within a period of 10 minutes from the testing device Normed according to ISO 1133 under a temperature of 230° C and under a weight of 2,16 kg. The Invention-based Propylene block co-polymers are manufactured without Mol mass reduction based on peroxide.

The Invention based Propylene block co-polymers exemplify themselves, among others, through a high degree of flow capability, that means through an enhanced melt flow rate under simultaneous rubber proportion. This denotes that the proportion of the propylene block co-polymer in the total propylene block co-polymer is more. Further, the invention-based propylene block co-polymers are characterized through a high degree of impact resistance and stiffness as well as through a good heat-forming resistance and flow capability in injection moulding (spiral flow property). They contain with all this, only relatively less low molecular substances, as for instance, n-Hepten or tert.Butanol.
Similarly the invention-based process can be carried out in the customary reaction of the plastic technology in a simple manner without the need for having the propylene block co-polymers subjected to a subsequent reduction of Mol mass.
The invention based propylene block co-polymers are suitable, above all for manufacture of foils, fibres and formed bodies.
Examples:
In all the invention based examples 1, 2 and 3 as well as the comparative examples A, B and C, Zieger-Natta-Catalyst system was applied, which encompasses the titanium containing solid material a) manufactured according to the following process.
In a first stage a fine particle silica gel, which has a mean particle dia of about 30 jim, a pore volume of 1,5 cm3/g and a specific surface of 260 m /g is added to a solution of n-Butyl Octyl Magnesium in n-Heptane, where per Mol Si02 0,3 mol of the magnesium compound was added. The fine particle silica gel was additionally characterized through a mean particle size of the primary particle of 3-5µm and through hollow space and canals with a dia of 3-5 µm, where the macroscopic volume proportion of the hollow space and canals on the total particle was about 15%. The solution was stirred for 45 minutes under 95°C, thereafter cooled to 20°C, after which the 10-time molar quantity, based on the magnesium organic compound in hydrogen chloride, was introduced. After 60 minutes, the reaction product was added under constant stirring with 3 mol ethanol per mol magnesium was added. This mixture was stirred 0,5 hours under 80°C and subsequently was added with 7,2 mol Titanium Tetrachloride and 0,5 mol Di-n-Butyl Phthalate each respectively based on 1 mol magnesium. Finally the compound was stirred for one hour under 100°C, and the solid stuff thus obtained filtered and washed with ethyl benzene several times.
The solid product obtained therefrom is extracted for three hours under 125°C with a lO-volume-% solution of titanium tetrachloride in ethyl benzene. Thereafter the solid product was separated through filtration from the extraction material and washed with n-Heptane so long till the extraction material had only of 0,3 weight-% of titanium tetrachloride.
The titanium containing solid components a) contain:

3,5weight-%Ti 7,4 weight-% Mg 28,2 weight-% CI
Besides the titanium containing solid components a) Tri-ethyl Aluminium and Di-methoxy Isobutyl Isopropylsilan were used as co-catalysts analogous to the gauge of US-A 4 857 613 and the US-A 5 288 824.
Example 1, 2 and 3
The process was carried out in all invention-related examples 1, 2 and 3 in two adjacent mixing auto claves, equipped with a cantilevered spiral mixture, with a rated volume of 200 1 each. Both reactors were provided with a movable fixed bed made of fine particle propylene polymer.
In the first polymerization reactor, the propylene was added in gas form and under a medium dwell-time, under pressure and a temperature according to table 1 was polymerized. The Ziegler-Natta-Catalyst System deployed for this purpose consisted of the titanium containing solid components a) as well as tri-ethyl alummium and isobutyl isopropyl di-methoxy-silane as catalysts. In this process the dosage of the solid components was so measured that the transfer from the first into the second polymerization reactor in mean free time corresponded to the values indicated in Table 1. The dosage of these components was done with the fresh propylene added for the purpose of pressure regulation. Similarly the following were also added into the reactor: as further catalyst substances tri-ethyl aluminium (in the form of a 1 molar heptane solution) in a quantity of 60 to maximum 105 ml/hour, and Isobutyl Isopropyl di-methoxy-silane (in the form of a 0,125 molar heptane solution) in a quantity of 70 to maximum 120 ml/hour. For regulating the melt flow rate (as per ISO 1133) hydrogen was added, and the hydrogen concentration in the reaction gas was gas chromatographically controlled.
By means of short-time recess of the reactors through an inunersion tube, successive polymer substance was removed firom the reactor. The propylene homo-polymer obtained in the first reactor was thereby discontinuously transferred with the catalysts into an intermediate container and converted there with Isopropanol (in the form of 0,5 molar heptane solution). The quantity of Isopropanol thus added -was so measured that the weight ratio between the propylene homo polymerisate obtained in the first reactor and the propylene propylene co-polymerisate produced in the secound reactor reached the values indicated in the following table I. The quantity of the Isopropanol added can also be split in a manner that it is added partially in the intermediate container and partially in the second reactor. In the intermediate container the pressure was reduced respectively to 1 bar and maintained at that level for 30 seconds long and fmally by injecting a gas mixture, corresponding to the composition in the second reactor, increased to 30 bar.

The polymer powder was transferred thereafter discontinuously from the intermediate container to the second reactor. There under a total pressure a temperature and a mean dwell-time corresponding to Table I, a compound made of propylene and ethylene was added to it for polymerization. The proportion of ethylene amounted to about 30 volume-% each. The weight ratio between the propylene homo polymer created in the first reactor, and the propylene co-polymer generated in the second reactor was controlled with the addition of Isopropanol and is indicated in Table I.
The precise conditions of the Example 1, 2 and 3 according to the Invention, that means the values for pressure, temperature and dwell-time, the quantity of hydrogen used, as well as the quantity of the co-catalysts, the melt-flow rate (MFR) and the transfer quantity, that means the quantity of the polymer respectively obtained for both polymerization reactors are given in the following Table I. Table I contains further the weight ratio between the propylene homo polymer obtained in the first polymerization reactor [PP (I)] and the propylene ethylene co-polymer (EPRII) obtained in the second polymerization reactor.
The proportion of the propylene-ethylene-co-polymerisate generated in the second reactor is calculated from the transfer and discharge quantities according to the following formula:

The process was carried out in all the invention-related examples 1', 2' and 3' in two adjacent mixing autoclaves, equipped with a cantilevered spiral mixture, with an effective volume of 200 1 each. Both reactors were provided with a movable fixed bed made of fine particle propylene polymer.
In the first polymerization reactor, the propylene was given in gas form and polymerized under a given dwell-time of 2,3 hours with the help of a Ziegler-Natta-Catalyst made of titanium containing solid components a), tri-ethyl aluminium and isobutyl isopropyle di-methoxy silane under a pressure and temperature as per Table IL In so doing, the dosage of the slid components was so measured that the charge/transfer from the first to the second polymerization reactor on an average corresponded to the values indicated in Table II. The dosage of these components was done together with the fresh propylene added for the purpose of pressure regulation. Similarly the following were also added to the reactor: tri-ethyl aluminium (in the form of a 1 molar heptane solution). For purpose of regulating the melting flow rate (as per ISO 1133) hydrogen was added, and the hydrogen concentration in the reaction gas was gas chromatographically controlled.
Using short-time de-stressing of the reactor by means of an immersion tube successive polymer grains were removed from the reactor. The propylene homo polymer generated in the first reactor was thus discontinuously charged into the second reactor with the catalyst and together with the unconverted or not decomposed monomers, without de-stressing them in an intermediate container.
There under a total pressure, a temperature and a mean dwell-time corresponding to Table II, a mixture of propylene and ethylene it is further polymerized. The proportion of ethylene accounted for 30 volume-% each. The weight ratio between the propylene homo polymer [PP (I)] generated in the first reactor and the propylene co-polymer [EPR (II)] generated in the second reactor is indicated in Table II. The following was similarly added in the second reactor; Isopropanol (in the form of a 0,5 molar heptane solution). The quantity added of Isopropanol was so measured that the weight ratio between PP (I) and EPR (II) was maintained as per figures given in Table 11.

Propylene block polymer obtained in the comparison examples 1', 2' and 3' was finally extruded, after a peroxide mol mass reduction with the help of a 5 weight-% solution of di-tert-butyl peroxide in n-Heptane (Luperox ® 101 of M/s. Interox/Peroxid Chemie) in a double-worm extruder (ZSK 30, Worm 8 A of M/s. Werner & Pfleiderer). In this manner, their melt flow rate (MFR) could be significantly enhanced. The melt flow rates before (MFR II) and after the reduction of the mol mass reduction (MFR after reduction) are indicated in the following Table II.

WE CLAIM:
1. A propylene block copolymer comprising from 50 to 80 wt% of a propylene homopolymer and from 20 to 50 wt% of a propylene copolymer containing from 10 to 70 wt% of a C2-C81-alkene other than propylene polymerized into it, obtainable by two-stage polymerization from the gas phase using a Ziegler-Natta catalyst system, where, in a first polymerization stage, propylene is polymerized at a pressiore of from 10 to 50 bar, a temperature from 50° to 100°C and a mean residence time of the reaction mixture of from 0.3 to 5 hours in the presence of at least 5.0 vol% of hydrogen in proportion to the total volume, and the propylene homopolymer obtained in the first polymerization stage is introduced along with the Ziegler-Natta catalyst system into an intermediate vessel, where it is firstly depressurized to less than 3.5 bar for from 0.1 to 5 minutes and maintained at a temperature of 10° to 80°C and the pressure in the intermediate vessel is raised again by 5 to 60 bar by the introduction under pressure of a gas mixture and the propylene homopolymer along with the Ziegler-Natta catalyst system is than transferred to a second polymerization stage where a mixture of propylene and a C2-C8 1-alkene is polymerized onto the propylene homopolymer at a pressure of from 10 to 50 bar, a temperature of from 50° to 100°C and a mean residence time of from 0.5 to 5 hours, and the weight ratio between the monomers reacted in the first and second polymerization stages is in the range of 4: 1 to 1: 1 said propylene black copolymer having a Melt Flow Rate ranging from2tol00g/10min.
2. The propylene block copolymer as claimed in claim 1, whose melt flow rate (MFR) at 230°C under a weight of 2.16 kg, measured in accordance to ISO 1133, satisfies the following equation (I):

MFR >101.39 + 0.0787 * XS2 -5.4674 * XS (I)
wherein XS is the proportion of the propylene copolymer, in percent based on the total propylene block copolymer.
3. The propylene block copolymer of claim 1 or 2, wherein the Ziegler-Natta catalyst system used comprises a titanium-containing solid component comprising, inter alia, a halogen-containing magnesium compound, an electron donor, and an inorganic oxide as support and also an aluminum compound and a further electron donor compound.
4. The propylene block copolymer of any of claims 1 to 3, wherein in the first polymerization stage propylene is polymerized at a pressure of 15 to 40 bar and at a temperature of 60 to 90°C.
5. The propylene block copolymer of any of claims 1 to 4, wherein 0.001 to 10 g, referred to the propylene homopolymer, of a C1-Cg alkanol are added per kg of the propylene homopolymer in the intermediate vessel.

6. The propylene block copolymer of any of claims 1 to 5, wherein after the depressurization the pressure in the intermediate container is raised again by from 10 to 40 bar by introducing a gas mixture under pressure.
7. The propylene block copolymer of any of claims 1 to 6, wherein in the second polymerization stage a mixture of propylene and a C2-C81-alkene is copolymerized at a pressure of 10 to 40 bar and at a temperature of 60° to 90°C.
8. A method for producing propylene block copolymers of any of claims 1 to 7, by two-stage polymerization from the gas phase using a Ziegler-Natta catalyst system, where in a

first polymerization stage, propylene is polymerized at a pressure of 10 to 50 bar, a temperature of 50° to lOO°C and a mean residence time of the reaction mixture of 0.3 to 5 hours in the presence of at least 5.0 vol% of hydrogen in proportion to the total volume and the propylene homopolymer obtained in the first polymerization stage is introduced along with the Ziegler-Natta catalyst system into an intermediate vessel, where it is first depressurized for 0.1 to 5 minutes to less than 3.5 bar and held at a temperature of 10° to 80°C and the pressure in the intermediate vessel is subsequently raised again by 5 to 60 bar by the introduction under pressure of a gas mixture and the propylene homopolymer along with the Ziegler-Natta catalyst system is then transferred to a second polymerization stage where a mixture of propylene and a C2-C8 1-alkene is polymerized onto the propylene homopolymer at a pressure of 10 to 50 bar, a temperature of 500 to lOO°C and a mean residence time of 0.5 to 5 hours, and the weight ratio between the monomers reacted in the first and second polymerization stages is in the range of 4:1 to 1:1 said propylene block copolymer having a Melt Flow Rate ranging from 2 to 100 g/10 min..
10. Films, fibers and molded articles comprising the propylene block copolymer as claimed in any of claims 1 to 7.

Documents:

in-pct-2002-2152-che-abstract.pdf

in-pct-2002-2152-che-claims filed.pdf

in-pct-2002-2152-che-claims grand.pdf

in-pct-2002-2152-che-correspondnece-others.pdf

in-pct-2002-2152-che-correspondnece-po.pdf

in-pct-2002-2152-che-description(complete) filed.pdf

in-pct-2002-2152-che-description(complete) grand.pdf

in-pct-2002-2152-che-form 1.pdf

in-pct-2002-2152-che-form 18.pdf

in-pct-2002-2152-che-form 26.pdf

in-pct-2002-2152-che-form 3.pdf

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Patent Number

209024

Indian Patent Application Number

IN/PCT/2002/2152/CHE

PG Journal Number

38/2007

Publication Date

21-Sep-2007

Grant Date

16-Aug-2007

Date of Filing

24-Dec-2002

Name of Patentee

BASELL POLIOLEFINE ITALIA S.P.A

Applicant Address

Via Pergolesi 25, I-20124 Milano

Inventors:

#	Inventor's Name	Inventor's Address
1	DAHN, Ulrich	Langstr. 39c 68169 Mannheim

PCT International Classification Number

C08F 10/06

PCT International Application Number

PCT/EP2001/005911

PCT International Filing date

2001-05-23

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	100 25 727.5	2000-05-25	Germany