Title of Invention

A POLYOLEFIN COMPOSITION

Abstract The present invention relates to a polyolefin composition comprising (percent by weight): A) 60%-95% of a crystalline polypropylene component having a Melt Flow Rate (MFRA) value (measured at 230 °C, with 2.16 Kg load) of from 2.5 to 50 gi10 min. and containing from 20% to 80% of a fraction A1 having a Melt Flow Rate (MFR1 value (measured at 230 °C, with 2.16 Kg load) of from 0.5 to 8 gi10 min., and from 20% to 80% of a fraction A II); (B) 5%-40% of a copolymer of ethylene with one or more C4-C1O a-olefin(s) containing from 10 to 40% of said C4-C1O a-olefin(s); said fractions A 1 and A II) being independently selected from propylene homopolymer3 and random copolymers of propylene containing up to 15% of ethylene and/or C4-C1O a-olefin(s); the ratio MFRA/MFRI being from 2 to 25; the percentages of A) and B) being referred to the sum of A) and B), and the percentages of A 1 and A II) being referred to the sum of A1 and A II).
Full Text IMPACT-RESISTANT POLYOLEFIN COMPOSITIONS
The present invention concerns polyolefin compositions comprising two polymer fractions
with different Melt Flow Rate values, selected from propylene homopolymers and
propylene-ethylene and/or other a-olefin random copolymers, and a copolymer of ethylene
with C4-C10 a-olefins.
The compositions of the present invention present a unique balance of processability,
mechanical properties and optical properties. In addition they present low/very low blush,
reduced blooming and low content of fraction extractable in organic solvents.
The said compositions can be easily processed by injection-molding and can be used for
several applications, including housewares and toys, and in particular for food-contact
applications.
Compositions comprising polypropylene and a rubbery phase formed by an elastomeric
copolymer of ethylene with a-olefins are already known in the art, and described in
particular in European patents 170 255 and 373 660. Said compositions present impact
resistance and, in the case of European patent 373 660, transparency values interesting for
many applications, however the overall balance of properties is still not totally satisfactory in
view of the high stardards required by the market. Therefore there is a strong demand for
compositions of this kind with improved properties.
Such a goal has now been achieved by the polyolefin compositions of the present invention,
comprising (percent by weight):
A) 60%-95%, preferably 70%-90%, more preferably 70%-88%, of a crystalline polypropylene component having a Melt Flow Rate (MFRA) value (measured at 230 °C, with 2.16 Kg load) of from 2.5 to 50, preferably from 5 to 50, more preferably from 10 to 30 g/10 min., and containing from 20% to 80%, preferably from 40% to 60%, of a fraction A1) having a Melt Flow Rate (MFR1) value (measured at 230 °C, with 2.16 Kg load) of from 0.5 to 8, preferably from 0.5 to 5, more preferably from 1 to 3 g/10 min., and from 20% to 80%, preferably from 40% to 60%, of a fraction A11);
B) 5%-40%, preferably 10%-30%, more preferably 12%-30%, of a copolymer of ethylene with one or more C4-C10 a-olefin(s) containing from 10 to 40%, preferably from 15 to 30%, more preferably from 15 to 25%, of said C4-C10 a-olefin(s);
said fractions A1) and A11) being independently selected from DroDvlene homopolymers and

random copolymers of propylene containing up to 15%, preferably up to 10%, of ethylene
and/or C4-C10 a-olefin(s); the ratio MFRA/MFR" being from 2 to 25, preferably from 4 to 20;
the percentages of A) and B) being referred to the sum of A) and B), and the percentages of
A) and A11) being referred to the sum ofA^andA").
From the above definitions it is evident that the term "copolymer" includes polymers
containing more than one kind of comonomers.
As previously said, the compositions of the present invention can be easily converted into
various kinds of finished or semi-finished articles, in particular by using injection-molding
techniques, as they possess relatively high values of MFR, associated with the said high
balance of properties (in particular, of flexural modulus, impact resistance, ductile/brittle
transition temperature, haze and gloss). The compositions of the present invention having
values of MFR (230 °C, 2.16 Kg) of the overall composition equal to or higher than 4 g/10
min., in particular equal to or higher than 5 g/10 min., are preferred.
The value of MFR of fraction A11) (MFR11) can be easily determined, on the basis of the
above said ranges of MFR1 and MFRA values, by means of the known correlation between
the MFR of a polyolefin composition and the MFR of the separate components, which, in the
present case, can be expressed as follows:
In MFRA = (WA"/WA1 + WA") x In MFRJ + (WA"/WA" + WA") x In MFR11
wherein WA" and WAn represent the weight of fractions A1) and A11) respectively.
Other preferred features for the compositions of the present invention are:
content of comonomer or comonomers in each of fractions A1) and A11) when at least one of them is selected from propylene copolymers: 0.5 to 15%, more preferably 0.5 to 10%, in particular 0.5 to 8% (0.5 to 5% when only ethylene is present, 1 to 10%, in particular 1 to 8%. when only C4-C10 a-olefin(s) are present);
content of polymer insoluble in xylene at room temperature (23 °C) (substantially equivalent to the Isotacticity Index) for fractions A1) and A11): not less than 80%, more preferably not less than 85%, in particular not less than 90%, for propylene copolymers; not less than 90%, more preferably not less than 95%, in particular not less than 97%, for propylene homopolymers, said percentages being by weight and referred to a single fraction;
Polydispersity Index (PI) for A): equal to or higher than 4, in particular from 4 to 12; Intrinsic Viscosity [n] of the fraction (of the overall composition) soluble in xylene at

room temperature: 0.8 to 2.5 dl/g, more preferably, when high transparency is
desired, 0.8 to 2, most preferably 0.8 to 1.9, in particular 0.8 to 1.5 dl/g. The compositions of the present invention present at least one melt peak, determined by way of DSC (Differential Scanning Calorimetry), at a temperature higher than 140-145°C. Component B) of the said compositions generally presents a melt peak, determined by way of DSC, at a temperature in the range from 120°C to 135°C. Such melt peak, which is attributable to a polyethylenic-type crystallinity, is generally detectable in the DSC pattern of the overall composition, particularly when component A) is made of propylene homopolymers. Moreover, the compositions of the present invention preferably have:
a Flexural Modulus of at least 700 MPa, in particular from 700 to 1300 MPa, when at
least one of fractions A1) and A11) is selected from propylene copolymers, or of at
least 1200 MPa, more preferably at least 1400 MPa, in particular from 1400 or 1500
to 2000 MPa, when component A) is made of propylene homopolymers (i.e., both
A1) and A11) are propylene homopolymers);
Izod values at 23 °C of at least 50 J/m, more preferably of at least 60 J/m in particular
from 50 or 60 to 500 J/m;
tensile strength at yield: 15-38 MPa;
elongation at break: higher than 40%;
substantially no whitening (blush) when bending a plaque 1mm thick;
fraction extractable in hexane (FDA 177, 1520): less than 10%, more preferably less
than 9%, in particular less than 5.5% by weight;
fraction soluble in xylene at room temperature: less than 20%, more preferably less
than 15%. The Ductile/Brittle transition temperature and the optical properties (Haze and Gloss) are strongly dependent upon the Intrinsic Viscosity (I.V.) of the fraction (of the overall composition) soluble in xylene at room temperature.
The ductile/brittle transition temperature is lower the greater the said I.V. and is generally equal to or lower than -2 °C, preferably equal to or lower than -5 °C, more preferably equal to or lower than -10 °C, the lower limit being indicatively of about-60 °C. Haze is lower the lower the said I.V. and is preferably lower than 30%>, more preferably equal to or lower than 25%, for compositions wherein component A) is made of propylene

homopolymers, equal to or lower than 20%, more preferably equal to or lower than 15%, for
compositions wherein at least one of fractions A1) and A11) is selected from propylene
copolymers. Said Haze values are measured on 1 mm thick plaques, prepared from nucleated
compositions (in particular with dibenzylidene sorbitols).
Gloss is higher the lower the said I.V. and is preferably in the range from 30 to 150%o, more
preferably from 40 to 130%o, measured in the same conditions as for Haze.
It is therefore clear that in addition to the previously said preferred ranges of I.V. of the
fraction soluble in xylene at room temperature, applicable when excellent optical properties
are desired, another preferred range of said I.V. exists, namely from more than 1.5 to 2.5
dl/g, applicable when low ductile/brittle transition temperatures, and consequently improved
impact resistance at low temperatures, are desired. In such range of I.V. the Haze values are
generally in the range from 45 to 75%.
The compositions of the present invention are also characterized by reduced levels of
blooming, as demonstrated by the fact that generally their Gloss values do not undergo a
decrease of more than 30% under ageing (for instance after 9 days of ageing at 80 °C).
The said C4-C10 a-olefins, that are or may be present as comonomers in the components and
fractions of the compositions of the present invention, are represented by the formula
CH2=CHR, wherein R is an alkyl radical, linear or branched, with 2-8 carbon atoms or an
aryl (in particular phenyl) radical.
Examples of said C4-C10 a-olefins are 1-butene, 1-pentene, 1-hexene, 4-methyl-l-pentene
and 1-octene. Particularly preferred is 1-butene.
The compositions of the present invention can be prepared by sequential polymerization in at
least three polymerization steps. Such polymerization is carried out in the presence of
stereospecific Ziegler-Natta catalysts. An essential component of said catalysts is a solid
catalyst component comprising a titanium compound having at least one titanium-halogen
bond, and an electron-donor compound, both supported on a magnesium halide in active
form. Another essential component (co-catalyst) is an organoaluminum compound, such as
an aluminum alkyl compound.
An external donor is optionally added.
The catalysts generally used in the process of the invention are capable of producing
polypropylene with an Isotacticity Index greater than 90%, preferably greater than 95%.
Moreover, said catalysts must have a sensitivity to molecular weight regulators (particularly

hydrogen) high enough to produce polypropylene having MFR values from less than 1 g/10
min. to 100 g/10 min. or more.
Catalysts having the above mentioned characteristics are well known in the patent literature;
particularly advantageous are the catalysts described in US patent 4,399,054 and European
patent 45977. Other examples can be found in US patent 4,472,524.
The solid catalyst components used in said catalysts comprise, as electron-donors (internal
donors), compounds selected from the group consisting of ethers, ketones, lactones,
compounds containing N, P and/or S atoms, and esters of mono- and dicarboxylic acids.
Particularly suitable electron-donor compounds are phthalic acid esters, such as diisoburyl,
dioctyl, diphenyl and benzylbutyl phthalate.
Other electron-donors particularly suitable are 1,3-diethers of formula:

wherein R1 and R11 are the same or different and are Ci-Cig alkyl, C3-C1B cycloalkyl or C7-C1R aryl radicals; R1I! and RIV are the same or different and are C1-C4 alkyl radicals; or are the 1,3-diethers in which the carbon atom in position 2 belongs to a cyclic or polycyclic structure made up of 5, 6 or 7 carbon atoms and containing two or three unsaturations. Ethers of this type are described in published European patent applications 361493 and 728769.
Representative examples of said dieters are 2-methyl-2-isopropyl-l,3-dimethoxypropane, 2.2-diisobutyl-l ,3-dimethoxypropane, 2-isopropyl-2-cyclopentyl-1,3-dimethoxypropane, 2-isopropyl-2-isoamyl-l,3-dimethoxypropane, 9,9-bis (methoxymethyl) fluorene. The preparation of the above mentioned catalyst components is carried out according to various methods.
For example, a MgC^ . nROH adduct (in particular in the form of spheroidal particles) wherein n is generally from 1 to 3 and ROH is ethanol, butanol or isobutanol, is reacted with an excess of TiCU containing the electron-donor compound. The reaction temperature is generally from 80 to 120 °C. The solid is then isolated and reacted once more with TiCU, in the presence or absence of the electron-donor compound, after which it is separated and

washed with aliquots of a hydrocarbon until all chlorine ions have disappeared.
In the solid catalyst component the titanium compound, expressed as Ti, is generally present
in an amount from 0.5 to 10% by weight. The quantity of electron-donor compound which
remains fixed on the solid catalyst component generally is 5 to 20% by moles with respect to
the magnesium dihalide.
The titanium compounds which can be used for the preparation of the solid catalyst
component are the halides and the halogen alcoholates of titanium. Titanium tetrachloride is
the preferred compound.
The reactions described above result in the formation of a magnesium halide in active form.
Other reactions are known in the literature, which cause the formation of magnesium halide
in active form starting from magnesium compounds other than halides, such as magnesium
carboxylates.
The active form of magnesium halide in the solid catalyst component can be recognized by
the fact that in the X-ray spectrum of the catalyst component the maximum intensity
reflection appearing in the spectrum of the nonactivated magnesium halide (having a surface
area smaller than 3 m2/g) is no longer present, but in its place there is a halo with the
maximum intensity shifted with respect to the position of the maximum intensity reflection
of the nonactivated magnesium dihalide, or by the fact that the maximum intensity reflection
shows a width at half-peak at least 30% greater than the one of the maximum intensity
reflection which appears in the spectrum of the nonactivated magnesium halide. The most
active forms are those where the above mentioned halo appears in the X-ray spectrum of the
solid catalyst component.
Among magnesium halides, the magnesium chloride is preferred. In the case of the most
active forms of magnesium chloride, the X-ray spectrum of the solid catalyst component
shows a halo instead of the reflection which in the spectrum of the nonactivated chloride
appears at 2.56 A.
The Al-alkyl compounds used as co-catalysts comprise the Al-trialkyls, such as Al-triethyl,
Al-triisobutyl, Al-tri-n-butyl, and linear or cyclic Al-alkyl compounds containing two or
more Al atoms bonded to each other by way of O or N atoms, or SO4 or SO3 groups.
The Al-alkyl compound is generally used in such a quantity that the Al/Ti ratio be from 1 to
1000.
The electron-donor compounds that can be used as external donors include aromatic acid

esters such as alkyl benzoates, and in particular silicon compounds containing at least one Si-
OR bond, where R is a hydrocarbon radical.
Examples of silicon compounds are (tert-butyl)2 Si (OCH3)2, (cyclohexyl) (methyl) Si
(OCH3)2, (phenyl)2 Si (OCH3)2 and (cyclopentyl)2 Si (OCH3)2. 1,3-diethers having the
formulae described above can also be used advantageously. If the internal donor is one of
these dieters, the external donors can be omitted.
As previously said, the polymerization process can be carried out in at least three sequential
steps, wherein components A) and B) are prepared in separate subsequent steps, operating in
each step, except the first step, in the presence of the polymer formed and the catalyst used in
the preceding step. The catalyst is added only in the first step, however its activity is such
that it is still active for all the subsequent steps.
Component A) is preferably prepared before component B).
In at least two (preferably consecutive) polymerization steps the relevant monomer(s) are
polymerized to form fractions A1) and An) and in the other step(s) a mixture of ethylene and
the C4-C10 a-olefin(s) is polymerized to form component B). Preferably, fraction A1) is
prepared before fraction A11).
The regulation of the molecular weight is carried out by using known regulators, hydrogen in
particular.
By properly dosing the concentration of the molecular weight regulator in the relevant steps,
the previously described MFR and [n] values are obtained.
The whole polymerization process, which can be continuous or batch, is carried out
following known techniques and operating in liquid phase, in the presence or not of inert
diluent, or in gas phase, or by mixed liquid-gas techniques. It is preferable to carry out the
polymerization in gas phase. However it is possible to carry out the propylene
(co)polymerization steps using liquid propylene as diluent, and the other polymerization
step(s) in gas phase. Generally there is no need for intermediate steps except for the
degassing of unreacted monomers.
Reaction time, pressure and temperature relative to the two steps are not critical, however it
is best if the temperature is from 20 to 100 °C. The pressure can be atmospheric or higher.
The catalysts can be pre-contacted with small amounts of olefins (prepolymerization).
The compositions of the present invention can also be obtained by preparing separately the
said components A) and B) or even fractions A1), A11) and component B), by operating with

the same catalysts and substantially under the same polymerization conditions as previously
explained (except that a wholly sequential polymerization process will not be carried out, but
the said components and fractions will be prepared in separate polymerization steps) and
then mechanically blending said components and fractions in the molten or softened state.
Conventional mixing apparatuses, like screw extrudres, in particular twin screw extruders,
can be used.
The compositions of the present invention can also contain additives commonly employed in
the art, such as antioxidants, light stabilizers, heat stabilizers, nucleating agents, colorants
and fillers.
In particular, the addition of nucleating agents brings about a considerable improvement in
important physical-mechanical properties, such as Flexural Modulus, Heat Distortion
Temperature (HDT), tensile strength at yield and transparency.
Typical examples of nucleating agents are the p-tert.-butyl benzoate and the 1,3- and 2,4-
dibenzylidenesorbitols.
The nucleating agents are preferably added to the compositions of the present invention in
quantities ranging from 0.05 to 2% by weight, more preferably from 0.1 to 1% by weight
with respect to the total weight.
The addition of inorganic fillers, such as talc, calcium carbonate and mineral fibers, also
brings about an improvement to some mechanical properties, such as Flexural Modulus and
HDT. Talc can also have a nucleating effect.
The particulars are given in the following examples, which are given to illustrate, without
limiting, the present invention.
Examples 1-4
In the following examples polyolefin compositions according to the present invention are
prepared by sequential polymerization.
The solid catalyst component used in polymerization is a highly stereospecific Ziegler-Natta
catalyst component supported on magnesium chloride, containing about 2.5% by weight of
titanium and diisobutylphthalate as internal donor, prepared by analogy with the method
described in the examples of European published patent application 674991.
CATALYST SYSTEM AND PREPOLYMERIZATION TREATMENT
Before introducing it into the polymerization reactors, the solid catalyst component
described above is contacted at -5 °C for 5 minutes with aluminum triethyl (TEAL) and

dicyclopentyldimethoxysilane (DCPMS), in a TEAL/DCPMS weight ratio equal to about 4
and in such quantity that the TEAL/Ti molar ratio be equal to 65.
The catalyst system is then subjected to prepolymerization by maintaining it in suspension in
liquid propylene at 20 °C for about 20 minutes before introducing it into the first
polymerization reactor.
POLYMERIZATION
The polymerization is carried out in continuous in a series of three gas phase reactors
equipped with devices for the transfer of the product coming from the reactor immediately
preceding to the one immediately following.
In gas phase the hydrogen and the monomer(s) are analyzed in continuous and fed in such a
manner that the desired concentration be maintained constant.
Into a first gas phase polymerization reactor a propylene homopolymer (Ex. 1-3) or
propylene/ethylene copolymer (Ex. 4) is produced by feeding in a continuous and constant
flow the prepolymerized catalyst system, hydrogen (used as molecular weight regulator) and
propylene and ethylene monomers in the gas state, thus obtaining fraction A1).
The polymer produced in the first reactor is discharged in the second reactor where a
propylene homopolymer (Ex. 1-3) or propylene/ethylene copolymer (Ex. 4) is produced by
feeding the monomer(s) and hydrogen in proper molar ratios, thus obtaining fraction A11).
The polymer produced in the second reactor is discharged in a continuous flow and, after
having been purged of unreacted monomers, is introduced in a continuous flow into the third
gas phase reactor, together with quantitatively constant flows of hydrogen and ethylene and
1 -butene monomers in the gas state. Component B) is thus obtained.
The polymer particles exiting the third reactor are subjected to a steam treatment to remove
the reactive monomers and volatile substances, and then dried.
Polymerization conditions, molar ratio of the reactants and composition of the polymers
obtained are shown in Table 1.
Then the polymer particles are introduced in a rotating drum, where they are mixed with
0.01% by weight of Irgafos 168 tris (2,4-di-tert-butylphenyl) phosphite, 0.05% by weight of
Irganox 1010 pentaerythrityl-tetrakis [3-(3,5-di-tert-butyl-4-hydroxy-phenyl)] propionate
and 0.16% by weight of Millad 3988 3,4-dimethylbenzylidene sorbitol.
Then the polymer particles are introduced in a twin screw extruder Berstorff ZE 25
(length/diameter ratio of screws: 33) and extruded under nitrogen atmosphere in the

following conditions:
Rotation speed: 250 rpm;
Extruder output: 6-20 kg/hour;
Melt temperature: 200-250 °C.
The data relating to the final polymer compositions reported in Table 2 are obtained from
measurements carried out on the so extruded polymers.
The data shown in the tables are obtained by using the following test methods. Molar ratios of the feed gases Determined by gas-chromatography. Ethylene and 1-butene content of the polymers Determined by I.R. spectroscopy. Melt Flow Rate MFR
Determined according to ASTM D 1238, condition L. Xylene soluble and insoluble fractions Determined as follows.
2.5 g of polymer and 250 cm3 of xylene are introduced in a glass flask equipped with a refrigerator and a magnetical stirrer. The temperature is raised in 30 minutes up to the boiling point of the solvent. The so obtained clear solution is then kept under reflux and stirring for further 30 minutes. The closed flask is then kept for 30 minutes in a bath of ice and water and in thermostatic water bath at 25 °C for 30 minutes as well. The so formed solid is filtered on quick filtering paper. 100 cm3 of the filtered liquid is poured in a previously weighed aluminum container which is heated on a heating plate under nitrogen flow, to remove the solvent by evaporation. The container is then kept in an oven at 80 °C under vacuum until constant weight is obtained. The weight percentage of polymer soluble in xylene at room temperature is then calculated. The percent by weight of polymer insoluble in xylene at room temperature is considered the Isotacticity Index of the polymer. This value corresponds substantially to the Isotacticity Index determined by extraction with boiling n-heptane, which by definition constitutes the Isotacticity Index of polypropylene. Polydispersity Index (PI) Accounts for the molecular weight distribution of the polymer. To determine the PI

value, the modulus separation at low modulus value, e.g. 500 Pa, is determined at a
temperature of 200°C by using a RMS-800 parallel plates rheometer model marketed
by Rheometrics (USA), operating at an oscillation frequency which increases from
0.01 rad/second to 100 rad/second. From the modulus separation value, the PI can be
derived using the following equation:
PI = 54.6 x (modulus separation)"176
wherein the modulus separation (MS) is defined as:
MS = (frequency at G" = 500 Pa)/(frequency at G" = 500 Pa)
wherein G" is the storage modulus and G" is the low modulus.
Hexane extractable fraction
Determined according to FDA 177, 1520, by suspending in an excess of hexane a
100 um thick film specimen of the composition being analyzed, in an autoclave at 50
°C for 2 hours. Then the hexane is removed by evaporation and the dried residue is
weighed.
Intrinsic Viscosity (I.V.)
Determined in tetrahydronaphthalene at 135 °C.
Melting temperature (Tm) and crystallization temperature (Tc)
Determined by DSC (Differential Scanning Calorimetry).
Flexural Modulus
Determined according to ISO 178.
Tensile strength at yield
Determined according to ISO R 527.
Elongation at yield
Determined according to ISO R 527.
Elongation at break
Determined according to ISO R 527.
Izod impact strength (notched)
Determined according to ISO 180/1A
Ductile/Brittle transition temperature (D/B)
Determined according to internal method MA 17324, available upon request.
According to this method, the bi-axial impact resistance is determined through
impact with an automatic, computerised striking hammer.

The circular test specimens are obtained by cutting with circular hand punch (38 mm
diameter). They are conditioned for at least 48 hours at 23°C and 50 RH and then
placed in a thermostatic bath at testing temperature for 1 hour.
The force-time curve is detected during impact of a striking hammer (5.3 kg,
hemispheric punch with a Vz" diameter) on a circular specimen resting on a ring
support. The machine used is a CEAST 6758/000 type model no. 2.
D/B transition temperature means the temperature at which 50% of the samples
undergoes fragile break when submitted to the said impact test.
Preparation of the plaque specimens
Plaques for D/B measurement, having dimensions of 127 x 127 x 1.5 mm are
prepared according to internal method MA 17283; plaques for Haze measurement, lmm thick, are prepared by injection moulding according to internal method MA 17335 with injection time of 1 second, temperature of 230 °C, mould temperature of
40 °C; plaques for gloss measurement, 1 mm thick, are prepared by injection
moulding according to internal method MA 17335, with injection time of 3 seconds,
temperature of 260 °C, mould temperature of 40 °C, description of all the said
methods beine available uDon reauest.
Method MA 17283
The injection press is a Negri Bossi type (NB 90) with a clamping force of 90 tons.
The mould is a rectangular plaque (127x127x1.5mm).
The main process parameters are reported below:
Back pressure (bar): 20
Injection time (s): 3
Maximum Injection pressure (MPa): 14
Hydraulic injection pressure (MPa): 6-3
First holding hydraulic pressure (MPa): 4±2
First holding time (s): 3
Second holding hydraulic pressure (MPa): 3±2
Second holding time (s): 7
Cooling time (s): 20
Mould temperature (°C): 60
The melt temperature is between 220 and 280 °C.

Method MA 17335
The injection press is a Battenfeld type BA 500CD with a clamping force of 50 tons.
The insert mould leads to the moulding of two plaques (55x60x1 mm each).
Preparation of the film specimens
Some films with a thickness of 50 um are prepared by extruding each test
composition in a single screw Collin extruder (length/diameter ratio of screw: 25) at a
film drawing speed of 7 m/min. and a melt temperature of 210-250 °C. Each resulting
film is superimposed on a 1000 um thick film of a propylene homopolymer having
an isotacticity index of 97 and a MFR L of 2 g/10 min. The superimposed films are
bonded to each other in a Carver press at 200 °C under a 9000 kg load, which is
maintained for 5 minutes.
The resulting laminates are stretched longitudinally and transversally, i.e. biaxially,
by a factor 6 with a TM Long film stretcher at 150 °C, thus obtaining a 20 urn thick
film (18 um homopolymer + 2 um test composition).
2 x 5 cm specimens are cut from the films.
Haze on plaque
Determined according to internal method MA 17270, available upon request.
The plaques are conditioned for 24 hours at R.H. 50±5% and 23±1°C.
The apparatus used is a Hunter D25P-9 colorimeter. The measurement and
computation principle are given in the norm ASTM-D1003.
The apparatus is calibrated without specimen, the calibration is checked with a haze
standard. The haze measurement is carried out on five plaques.
Gloss on plaque
Determined according to internal method MA 17021, available upon request.
The photometer used is a Zehntner model ZGM 1020 or 1022 set with an incident
angle of 60°. The measurement principle is given in the Norm ASTM D2457.
The apparatus calibration is done with a sample having a known gloss value. One
gloss measure is obtained by the measurement on three plaques at two different
locations on the same plaque.
Haze on film
Determined on 50 um thick films of the test composition, prepared as described
above. The measurement is carried out on a 50 x 50 mm portion cut from the central

zone of the film.
The instrument used for the test is a Gardner photometer with Haze-meter UX-IO
equipped with a G.E. 1209 lamp and filter C. The instrument calibration is made by
carrying out a measurement in the absence of the sample (0% Haze) and a
measurement with intercepted light beam (100% Haze).
Gloss on film
Determined on the same specimens as for the Haze.
The instrument used for the test is a model 1020 Zehntner photometer for incident
measurements. The calibration is made by carrying out a measurement at incidence
angle of 60 ° on black glass having a standard Gloss of 96.2% and a measurement at
an incidence angle of 45 ° on black glass having a standard Gloss of 55.4%.






Note to the tables:
C2" = ethylene; C3" = propylene; C4~ = 1-butene; C{ (total) = ethylene content of polymer discharged from the specified reactor; Amount produced = amount of polymer produced in the specified reactor; X.I. = Xylene Insoluble fraction; X.I. (total) = X.I. of polymer discharged from the specified reactor; X.S. = Xylene Soluble fraction; H.E. = Hexane Extractable fraction; all percent amounts (except for elongations and Haze) are by weight.



WE CLAIM:
1. A polyolefin composition comprising (percent by weight):
A) 60%-95% of a crystalline polypropylene component having a Melt Flow Rate (MFRA) value (measured at 230 °C, with 2.16 Kg load) of from 2.5 to 50 g/10 min. and containing from 20% to 80% of a fraction A1) having a Melt Flow Rate (MFR1) value (measured at 230 °C, with 2.16 Kg load) of from 0.5 to 8 g/10 min., and from 20% to 80% of a fraction A11);
B) 5%-40% of a copolymer of ethylene with one or more C4-Ci0 a-olefin(s) containing from 10 to 40% of said C4-Ci0 a-olefin(s);
said fractions A1) and A11) being independently selected from propylene homopolymers and random copolymers of propylene containing up to 15% of ethylene and/or C4-Ci0 a-olefin(s); the ratio MFRA/MFRI being from 2 to 25; the percentages of A) and B) being referred to the sum of A) and B), and the percentages
of A1) and A11) being referred to the sum
ofAVridA11).
2. The polyolefin composition as claimed in claim 1, having Melt Flow rate values (230 °C, 2.16 Kg) equal to or higher than 4 g/10 min.
3. The polyolefin composition as claimed in claim 1, wherein the intrinsic viscosity of the fraction soluble in xylene at room temperature is in the range from 0.8
to 2.5 dl/g.
4. The polyolefin composition as claimed in claim 1, wherein the content of comonomer or comonomers in each of fractions A1) and A11), when at least one of them is selected from propylene copolymers, is in the range from 0.5 to 10% by weight.
5. The polyolefin composition as claimed in claim 1, wherein the content of polymer soluble in xylene at room temperature in fractions A1) and A11) is not less than 80% for propylene copolymers, or not less than 90% for propylene homopolymers (said percentages being by weight and referred to the weight of a single fraction).

6. The polyolefin composition as claimed in claim 1, having a Ductile/Brittle
transition temperature equal to or lower than -2 °C.
7. A process for producing the polyolefin composition as claimed in claim 1,
which comprises three sequential steps, wherein in at least two polymerization steps
propylene and optionally ethylene and / or C4-C10 a-olefin(s) are (co) polymerized to
form fractions A1) and A11) respectively in the said weight amounts, and in the other
step or steps a mixture of ethylene and C4-Q0 a-olefin(s) is polymerized to form
component B) in the said weight amounts, operating in each step, except the first step,
in the presence of the polymer formed and the catalyst used in the preceding step.
8. The process as claimed in claim 7, wherein the polymerization catalyst is a
stereospecific Ziegler-Natta catalyst comprising, as catalyst-forming components, a
solid component comprising a titanium compound having at least one titanium-
halogen bond and an electron-donor compound, both supported on a magnesium
halide in active form, and an organoaluminum compound.
9. The process as claimed in claim 7, wherein all the polymerization steps are carried out in gas phase.
10. The process as claimed in claim 7, wherein the propylene (co) polymerization steps are carried out using liquid propylene as diluent, and the other polymerization step(s) are carried out in gas phase.

Documents:

in-pct-2001-0806-che abstract-duplicate.pdf

in-pct-2001-0806-che abstract.pdf

in-pct-2001-0806-che claims-duplicate.pdf

in-pct-2001-0806-che claims.pdf

in-pct-2001-0806-che correspondence-others.pdf

in-pct-2001-0806-che correspondence-po.pdf

in-pct-2001-0806-che description (complete)-duplicate.pdf

in-pct-2001-0806-che description (complete).pdf

in-pct-2001-0806-che form-1.pdf

in-pct-2001-0806-che form-19.pdf

in-pct-2001-0806-che form-26.pdf

in-pct-2001-0806-che form-3.pdf

in-pct-2001-0806-che form-4.pdf

in-pct-2001-0806-che form-5.pdf

in-pct-2001-0806-che others.pdf

in-pct-2001-0806-che petition.pdf


Patent Number 202381
Indian Patent Application Number IN/PCT/2001/806/CHE
PG Journal Number 05/2007
Publication Date 02-Feb-2007
Grant Date 03-Oct-2006
Date of Filing 13-Jun-2001
Name of Patentee M/S. BASELLTECH USA INC
Applicant Address Suite 1704 300 Delaware Avenue Wilmington, DE 19803
Inventors:
# Inventor's Name Inventor's Address
1 CECCHIN, Giuliano Via dei Gelsomini, 50 I-44100 Ferrara
2 PELLICONI, Anteo Via Volta, 22 I-45030 Santa Maria Maddalena
3 SGARZI, Paola Via Borgo dei Leoni, 83 I-44100 Ferrara
4 FERRARI, Paolo Via Scandiana, 24A I-44100 Ferrara
PCT International Classification Number C08L 53/00
PCT International Application Number PCT/EP2000/008790
PCT International Filing date 2000-09-08
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 99202974.4 1999-09-14 EUROPEAN UNION