Indian Patents. 216545:"THERMOPLASTIC ELASTOMER COMPOSITIONS FROM BRANCHED OLEFIN COPOLYMERS"

Title of Invention	"THERMOPLASTIC ELASTOMER COMPOSITIONS FROM BRANCHED OLEFIN COPOLYMERS"
Abstract	A process for the preparation of a thermoplastic elastomer composition comprising the steps of copolymerizing by contacting ethylene, with an activated transition metal metallocene olefin polymerization catalyst to form a copolymer having greater than 40% chain end-group unsaturation; copolymerizing the product of Step A) to prepare said thermoplastic elastomere.

Full Text	The present invention relates to a process for the preparation of a thermoplastic elastomer. Technical Field The invention relates to thermoplastic elastomer composition comprised of branched olefin copolymers having crystallizable polyolefin sidechains incorporated into low crystallinity polyethylene backbones. Background Art Triblock and multi-block copolymers are well-known in the art relating to elastomeric polymers useful as thermoplastic elastomer ("TPE") compositions due to the presence of "soft" (elastomeric) blocks connecting "hard" (crystallizable or glassy) blocks. The hard blocks bind the polymer network together at typical use temperatures. However, when heated above the melt temperature or glass transition temperature of the hard block, the polymer flows readily exhibiting thermoplastic behavior. See, for example, G. Holden and N.R. Legge, Thermoplastic Elastomers: A Comprehensive Review, Oxford University Press (1987). The best commericially known class of TPE polymers are the styrenic block copolymers (SBC), typically linear triblock polymers such as styrene-isoprene-styrene and styrene-butadiene-styrene, the latter of which when hydrogenated become essentially styrene-(ethylene-butene)-styrene block copolymers. Radial and star branched SBC copolymers are also well-known. These copolymers typically are prepared by sequential anionic polymerization or by chemical coupling of linear diblock copolymers. The glass transition temperature (T g)of the typical SBC TPE is equal to or less than about 80-90°C,_ thus presenting a limitation on the utility of these copolymers under higher temperature use conditions. See, "Structures and Properties of Block Polymers and Multiphase Polymer Systems: An Overview of Present Status and Future Potential", S. L. Aggarwal, Sixth Biennial Manchester Polymer Symposium (UMIST Manchester, March 1976) Insertion, or coordination, polymerization of olefins can provide economically more efficient means of providing copolymer pioducts, both because of process efficiencies and feedstock cost differences. Thus useful TPE polymers from olefmically unsaturated monomers, such as ethylene and C3-C8 α olefins, have been developed and are also well-known. Example;, include the physical blends of thermoplastic olefins ("TPO") such as polypropylene with ethylene-propylene copolymers, and similar blends wherein die ethylene-propy ene, or ethylene-propylene -diolefm phase is dynamically vulcanized so as to maintain well dispersed, discrete soft phase particles in a polypropylene matrix. See, N.R. Legge, "Thermoplastic elastomer categories: a comparison of physical properties". ELASTOMERICS. pages 14-20 (Sept., 1991), and references cited therein. The use of metallocene catalysts for olefin polymerization has led to additional contributions to the field. U.S. patent 5,391,629 describes thermoplastic elastomer compounds comprising tapered and block linear polymers from ethylene ard alpha-olefin monomers. Polymers having herd and soft segments arc said to be possible with single site metallocene catalysts that are capable of preparing both segments. Examples are provided of linear thermoplastic elastomers having hard blocks of high density polyethylere or isotactic polypropylene and soft blocks of ethylene-propylene rubber. Japanese Early Publication H4-337308(1992) describes what is said to be .1 polyolefk copolymer product made by polymerizing propylene first so as to form an isotactic polypropylene and then copolymerizing the polypropylene with ethylene and propylene, both polymerization in the presence of an organoaluminum compound and a silicon-bridged, biscyclopentadienyl zirconium dihalide compound. Datta, et al (D.J. Lohse, S. Datta, and E.N. Kresge, Macromolecules 24, 561 (1991) described EP backnbones functionalized with cyclic diolefins by terpolymerization of ethylene, propylene and diolefin. The statistically functionalized EP "soft bloc" was then copolymerized with propylene in the presence of a catalyst producing isotactic polypropylene. In this way, some of the "hard" block polypropylene chains were grafted through the residual olefinic unsaturatuion onto the EP "soft" block as they were formed. See also, EP-A-0 366 411. A limitation of this class of reactions, in which chains with multiple functionalities are used in subsequent reactions, is the formation of undesirable high molecular weight material typically referred to as gel in the art, U.S. patent 4, 999, 403 describes similar graft copolymer compounds where functional groups in the EPR backbone are used for grafting isotactic polypropylene having reactive groups. In both the graft copolymers are said to be useful as compatibilizer compounds for blends of isotactic polypropylene and ethylene-propylene rubber. Summary of the Invention Accordingly, there is provided a process for the preparation of a thermoplastic elastomer composition comprising the steps of: A] copolymerizing by contacting ethylene, optionally with one or more copolymerizable monomers selected from the group consisting of C3-C20 alpha olefins, germinally disubstituted monomers, C5-C25 cyclic olefins, styrenic olefins, C3-C8 alkyl substituted analogs of C5-C25 cyclic olefins, and C3-C8 alkyl substituted analogs of styrenic olefins, with an activated transition metal metallocene olefin polymerization catalyst of the kind such as herein described, in a polymerization reaction at a temperature from 20°C to 200°C to form a copolymer having greater than 40% chain end-group unsaturation; B] copolymerizing the product of Step A) with ethylene and one or more copolymerizable monomers so as to prepare said thermoplastic elastomer, wherein the thermoplastic elastomer comprises a branched olefine copolymer comprising: i] sidechains with number-average molecular weight greater than 10, 000 and less than 45, 000, a T g as measured by DSC less than or equal to 10°C; and Tm greater than 80°C; ii] elastomeric backbone polymeric segments having a T g as measured by DSC less than or equal to -10°C; iii] an elongation at break of greater than or equal to 300%; iv] a Tensile strength of greater than or equal to 1,500 psi (10,300 kPa); and v] an elastic recovery of greater than or equal to 50%, wherein the mass of the elastomeric backbone segments comprise 40 wt% to 60 wt% of the total polymer mass. Brief Description of Figures Fig. 1 illustrates a comparison of measured physical properties of branched olefin copolymers of the invention with a commercially available styrene block copolymer thermoplastic elastomer. Detailed Description of the Invention The thermoplastic elastomer compositions of this invention are comprised of branched copolymers wherein both the copolymer backbone andpoymeric sidechains are derived from monoolefins polymerized under coordination or insertion conditions with activated transition metal organometallic catalyst compounds. The sidechains are copolymerized so as to exhibit crystalline, semi-crytalline, or glassy properties suitable for hard phase domains in accordance with the art understood meaning of those terms and are attached to polymeric backbone that is less crystalline or glassy than the sidechains, preferably, substantially amorphous, so as to be suitable for the complementary soft phase domains characteristic of thermoplastic elastomer compositions. The cryjtalli/able sidechains are comprised of chemical units capable of forming crystalline or glassy polymeric segments under conditions of insertion polymerization. Known monomers meeting this criteria are ethylene, propylene, 3-mi:thyi-l-pentene, and copolymers thereof, including ethylene ccpolymers with α-ohfm, cyclic olefm or styrcnic comonomers. Ethylene or propylene copolymcr sider.hains are preferable provided that the amount of comonomer is insufficient to disrupt the crystallinity such that the Tm is reduced below 80°C. Suitable comonomers include C3-C20 α-olefins or geminally disubstituted monomers, C5-C25 cyclic clef ins, styrenic olefins and lower carbon number (C3-C8) alkyl-substiuted analogs of the cyclic and styrenic olefins. Thus, typically, the sideohains can comprise from 85-100 rnol% elhylene, and from 0-15 mol% comonomer, preferably 90 -99 mol% ethylene and 1-10 mol% comonomer, most preferably 94 -98 mol% ethylene and 2-6 mol% comonomer. Alternatively, the sidechains can comprise from 90-100 mol% propylene, and from 0-10 mol% comonomer, preferably 92-99 rnol% propylene and 1-8 mol% comonomer, most preferably 95-98 mol% propyler e and 2-5 mol'/o comonomer. In particular, as the sidecnain Mn increases above about 3,0[)0, it is preferable to introduce small amounts of comonomer to minimize embrittlement, e.g., about 0.2 - 4.0 mol.% comonomer, The selection of comonomer can be based upon properties other than cryslallinitv dismpting capability, for instance;, a longer olefin comonomer, such as 1-octene, may be preferred over a shorter olefm such as 1-butenc for improved polyethylene film tear. For improved polyethylene film elasticity or barrier properties, a cyclic comonomer such as lorbornene or aliyl-sub.stituted norbirnene may be preferred over an a-olefin. The sidechains can have narrow or broad molecular weight distribution (Mw/Mn) for example, from 1.1 to 30. typically 2-8. Additionally, the sidechains can have different commonoer compositins, e.g., including the orthogonal compositional cistributions described in U.S. patent 5,382,630 (CDBI >50%), incorporated by reference for purposes of U. S. patent practice. Optionally, mixtures of sidcchains with different molecular weights and/or compositions may be used. The Mn of the side-chains are within the range of from greater than or equal to 1 500 and less than or equal to 45,000 Preferably the Mn cf the sidechains is from 1,500 to 30,000, and more preferably the Mn is from 1,500 to 25,000. The number of sidechains is related to the Mn of 'he sidechains such that the total weight ratio of the weight of the sidechains to the total weight of the polymeric backbone segments between and outside the incorporated sidechains is less than 60%, preferably 40-50%. Molecular weight her: is determined by gel permeation chromatography (GPC) and differential refractive index (DRI) measurements. A preferred branched olefiaic copolymer within this class will have an enthalpy of fusion (Hf) a measured by differential scanning calorimetry of ≤ 90 cal/g (meaured by integrating heat flows recorded at temperatures 5 80 °C while scantling at ≥ 5 oC/min). The backbone, or backbone polymeric segments, when taken together with the sidechain interruption of the backbone structure, should have a lower Tn, (or Te if not exhibiting a Tm) than the sidechains. Thus it will preferably comprise segments of chemical units not having a measurable crystallinity, or having a Te lower than -10 °C. The backbone segments as taken together typically will have a Tm less than or equal to 80 °C and a Tg less than or equal to -10 °C. Elastomeric backbones will be particularly suitable, such will be typically comprised of ethylene and one or more of C3-C12 α-olcfms or diolefins, particularly prcpylene and 1-buteiie. Other copolymerizable monomers include geminally disubstituted olefirus such as isobutylene, cyclic olefins such as cyclopentene, norbornene and alkyl-substitutec norbornenes, and styrenic monomers such as styrcne and alkyl substituted styrenes. Low crystallinity backbones are suitable, examples are high comonomer content ethylene copolymers (as described before), e.g., > than 8 mol% comonomer. As indicated aboe the mass of the backbone will typically comprises at least 40 wt% of the total polymer mass, that of the backbone and the sidechains together, so the backbone typically will have a nominal weight-average molecular weight (Mw) weight of at least equal to or greater than about 50,000. The term nominal is used to indicate that direct measurement of Mw of the backbone is largely impossible but that characterization of the copolymer product will exhibit measurements of Mw that correlate to a close approximate weight of the polymeric backbone inclusive only of the monoolefin mer derivatives and the insertion moieties of the sidebranches. The branched olefin compolymers comprising the above sidechains and backbones will typically have an Mw equal to or greater than 50,000 as measured by GPC/DRI as defined for the examples. The Mw typically can exceed 300, 000, preferably 200, 000, up to 500, 000 or higher. The thermoplastic elastomer composition of the invention can be prepared by a process comprising : A) copolymerizing ethylene or propylene, optionally with one or more copolymerizable monomers, in a polymerization reaction under conditions sufficient to form a copolymer having greater than 40% chain end-group unsaturation, a Tm≥800C and a Tg ≤10°C; B) copolymerizing the product of A) with ethylene and one or more copolymerizable monomers so as to prepare said branched olefin copolymer. For ethylene-based macromers prepared in step A), the Tgpreferably less than -5°C, more preferably less than -10°C. Accordingly, in a preferred embodiment, the branched olefin copolymer of the present invention comprises sidechains derived from propylene, optionally with one or more copolymerizable monomers, such that the Tg of the sidechains is less than -10°C, and the Tm is greater than or equal to 110°C. The process step A) can be usefully practiced in a solution process in which ethylene and, optionally, one or more copolymerizable monomers, is contacted with a transition metal olefin polymerization catalyst activated by an alkylulumoxane cocatalyst, the mole ratio of aluminum to transition metal being less than about 220:1. The terminally unsnturated copolymer population so formed, with or without separation from copolymer product having only saturated ends, can then be copolymerized with ethylenc and copolymcrizablc monomers in a separate reaction by solution, slurry or gas phase cthyiene polymerization with an activated transition metal insertion polymerization catalyst, particularly a catalyst capable of incorporating the cthyiene copolymers into said brzmched olefin copolymer. Alternatively, the process step A) can be practiced in a solution process in which propylene and, optionally, one or more copolyrnerizable monomers, is contacted with a stereorigid transition metal olefin polymerization catalyst, one capable of producing stereregular polypropylene, activated by any suitable cocatalyst, the reaction temperature kept at sufficiently high levels so as to achieve significant populations of terminally unsaturated polymer chains, e.g;., greater than about 85 °C, preferably greater than about 90 °C. The terminally unsaturated copo ymer population so formed, with or without separation from copolymer product having only saturated ends, can then be copolymerized with ethylene and copoiymerizable monomers, or other selection of monomers suitable for the prepfiration of low crystallinity polymers, in a separate reaction by solution, slurry or gas phase ethylene polymerization with an activated transition metal insertion polymerization catalyst, particularly a catalyst capable of incorporating the propylene copolymers into said branched olefin copolymer having the low crystellinity backbone. Conditions sufficient to form the sidediain ethylene copolymer include using; suitable ethylene and comonomer reactant ratios to assure the described sidechain olefin-derived unit constitution, plus catalyst and process conditions conducive to fomiing the unsasurated chain ends. The teachings of copending provsional application U.S. Ser. No. 60/037323 filed 02/07/97 are specific to suitable catalyst selection and use to prepare raacromeric copolymer chains with a high yield of vinyl unsaturation. The raetallocene catalyst used in the step A) preparation of the unsaturation-cntaining macromcr can be essentially any catalyst capable of insertion polymerization of ethylene, it can be one capable of high comonorner incorporation capability (sec below) or of low comoriomcr incorporation capability. Those of low incorporation capability are typically those that are more congested at the metal coordination site, thus unbridged and substituted unbridged metallocene catalysts are particularly suitable. See also the teachings of U.S. Patent 5,498,809 and international publications WO 94/19436 and V'O 94/13715, describing means of preparing vinylidene-tcnninated ethylene-l-butcne copoly-ners in high yields. Sec also, the teachings of copending application U.S. Ser. No. 08/651,030, filed 21 May 1996, as to the preparation of ethylene-isobutylenc copolymer; having high levels of vinylidene chain-end unsatoration. Throughout the description above, and below, the phrase "chain-end" or "terminal" when referring to unsaturution means olefin unsatiiration buitablc for insertion polymerisation whether or not located precisely at the terminus of a chain. Sec also U.S. paten:s 5,324,801 and 5,621,054 addressing alternating ethytene-cyclic olefin copolymers having crystalline melting points of 235 °C, and up, macromers produced with the suitable catalysts of these descriptions will have glassy attributes effective for functioning as the hard phase component of the thermoplastic elastomers of this invention. All documents of this paragraph ore incorporated by reference for purposes of U.S. patent practice. In a particular embodiment, polymeric vinyl-containing, ethylene-contuning ma;romer product, suitable as branches for a subsequent copclymerization reaction, can be prepared under solution polymerization conditions wilh preferred molar ratios of aluminum in the alkyl aluraoxane activator, e.g.. methly almoxane (MAO), to transition metal. Preferably that level is ≥ 20 and ≤175; more preferably ≥ 20 and ≤ 140; and. most preferably ≥ 20 and ≤ 100. The temperature, pressure and time of reaction depend upon the selected process but are generally within the normal ranges for a solution process. Thus temperatures can range from 20°C to 200°C, preferably from 306C to 150oC, and more preferably from 50°C to 140°C. The pressures of the reaction generally can vary from atmospheric to 345 MPa, preferably to 182 MPa, For typical solution rcacti nns, temperatures will typically range from ambient to 190 °C with pressures from ambient lo 3.45 MPa. The reactions can. be run batchwise. Conditions for suitable slurry-type reactions are similar to solution conditions except reaction temperatures are limited to those below the melt temperature of the polymer. In an additional, alternative reaction configuration, a supercritical fluid medium can be used with temperatures up to 250°C and pressures up to 345 MPa. Under high temperature anc pressure reaction conditions, macromer product of lower mole:ular weight ranges are typically produced, e.g., Mn about 1,500-. In an alternative embodiment, polymeric vinyl-containing, propylene-containing macromer product, suitable as branches for a subsequent copolymerization reaction, car. be prepared under solution polymerization conditions with metallocsne catalysts suitable for preparing either of isotactic or syndiotactic polypropylene. A prefcired reaction process ibr propylenc maciomers having high levels of terminal vinyl unsaturation is described in co-pending U.S. application 60/ 067,783, filed December 10, 1997, Attorney Docket No. 97B075. Typically used catalysts are stereorigid, chiral or asymmetric, bridged metal lccenes. See, far example, U.S. patent 4,892,851, U.S. patent 5,017,714, U.S. patent 5,132,281, U.S. patent 3,155,080, U.S. patent 54W34, U.S. patent 5.278,264, U.S. patent 5,318,935, WO-A-(PCT/US92/10066), WO-A-93/19103, EP-A2-0 577 581, EP-A1-0 578 838, and academic literature "The Influence of Aromatic Substitusnts on the Polymerization Behavior of Bridged Zirconocene Catalysts", Spaleck. W., et al, Organometallics 1994, 13, 9:54-963, and "ansa-zirccnocene Polymerization Catalysts with Annelared Ring Ligands-Effects on Catalytic Activity and Polymer Cham Lengths", Rrinzinger, H., et al, Organometallcy 1994, 13,964-370, and documents referred to therein. Preferably, for isotatic polypropylene, the stereorigid transition metal catalyst compound is selected from the group consisting of bridged bis(indcnyl) zirconoccncs or hafnocenes. In a preferred embodiment, the transition metal catalyst compound is a dimcthylsilyl-bridged bis(indenyl) zirconocene or hafnocene. More preferably, the transition metal catalyst compound is dimelhylsilyl (2--methyl-4-phenylindenyl) zirconium or hafniumdichloride or dimelhyl. In another preferred embodiment, the transition metal catalyst is a dimcthylsilyl-bridged bis(indcnyl) hafnocene such as dimethylsiiyl bis(indenyl)hafnium dimethyl or dichloride. The method for preparing propylene-based maeromers: having a high percentage of vinyl terminal bonds involves: a) contacting, in solution, propyicne, optionally a minor amount of copolymerizable monomer, with a catalyst composition containing the stereorigid, activated transition metal catalyst compound at a temperature from about 90°C to about 120°C; and b) recovering isotactic or syndiotacuc polypropylene chains having number average molecular weights of about 2,000 to about 150,000 Daltons. Preferably, the solution comprises a hydrocarbon solvent. More preferably, the hydrocarbon solvent is aromatic. Also, the prcpylenc monomers are preferably contacted at a temperature from 95oC to 115°C. More preferably, a temperature from 100CC to 110°C is used. Most preferably, the propylene monomers are contacted at a temperature ftom 105oC to 110°C. The pressures of the reaction generally can vary from atmospheric to 345 MPa, preferably to 132 MPa The read ions can be run batchwise or continuously. Conditions for suitable slurry-type reactions will also be suitable and arc similar to solution conditions, the polymerization typically being run in liquid propylene under pressures suitable to such. All documents are incorporated by reference for purposes of U.S. patent practice. Additionally the invention branched olefin copolymer thermoplastic elastomer composition can be prepared directly from the selected clefins concurrently in t!\e presence of a mixed catalyst system comprising at leajt one first transition metal olefin polymerization catalyst capable of preparing ethylene or propylene copolymers having greater than 40% chain end-group unsatwation and at least one second transition metal olefin polymerization catalyst capable of incorporating the ethylene or propylene homopolymcr or copolymer sidechains into said branched olefin copolymer. This in situ method can be practiced by any method that permits both preparation of unsaturaled macromers having crystalline, semi-crystalline or glassy properties and copolymerization of the nracromers with comonomers constituting the low crystallinitybackbnoe such that the branched copolymer is prepared. Gas phase, slurry and solution processes can bs used under conditions of temperature and pressure known to be useful in such processes. Suitable first catalyst compounds that when activated car achieve high chain-end unsatiarations specifically include those identified above with respect to the preparation of high vinyl or vinylidene-containing macromers. Preferably, catalysts that are active for ethylene homopolymerization but do not incorporate higher carbon number monomers appreciably as discussed above, or do :so only with attendant decrease in Mn, will be particularly suitable for the crystalline or glassy sidechaiii preparation in :he concurrent, or in situ, methoci of preparing the invention thermoplastic copolymer compositions of the invention, so long as the Mn can be raised or maintained above the sidechain minimium. Suitable second catalyst compounds include those that are capable of good comonomcr incorporation without significant depression in Mn for the polymeric backbone under the temperature and pressure conditions used. The teachings of copending provisional application U.S. Scr. No. 60/037323 filed 02/07/97 are specific to suitable catalyst selection and us.e to prepare branched olefin copolymers and addresses catalyst compounds suitable for high comonomcr and macromonomer incorporation. As indicated therein, preferred catalyst compounds for assembling the branch olefin copolymers from vinyl- or vinylidene containing macrnmers, ethylene and copolymerizable comonomers include the bridged biscyclopentadienyl and monocyclopentadienyl Group 4 metal compounds of U.S. patents 5,198,401, 5,270,393, 5,324,801, 5,444,145, 5,475,075, 5,635,573, International applications WO92/00333 and WO 96/00244; see also the unbridged monoeyclopentadienyl Group 4 metal compounds of copending application 08/545,973, filed 10/20/95, and the bis-amido and bis-arylamido transition metal catalysts of U.S. patent 5,318,935 and copending U.S. patent application 08/ 803,(i87, filed 2/24/97, and the a-diimine nickel catalyst complexes of WO 96/2J010. In accordance • with these teachings, the transition metal catalyst comjKiunds are typically used with activating co-catalyst components as described, e.g., alky I alumoxanes and ionizing compounds capable of providing a stabilizing non-coordinating anion. The teachings of each of the documents of this paragraph arc also Incorporated by reference for purposes of U.S. patent practice. Industrial Applicability The theimoplastic elastomer compositions according to the invention will have- use in a variety of applications wherein other thermoplastic elastomer composition have found use. Such uses include, but are not limited to. those known tor the styrene block copolymers, e.g., styrene-isopretie-styrene and styrsne-butadiene-styrene copolymers, and their hydrogenatec analogs. Such include a variety of uses such as backbone polymers in adhesive compositions and molded articles These applications will benefit from the increased use temperature range, typically exceeding the 80 - 90 °C limitation of the SBC copo ymer compositions. The compositions of the invention will also be suitable as compatibilizer compounds for polyolefin blends. Additionally, due to the inhcre nt tensile strength, elasticity, and ease of melt processing, extruded film, coating and packaging compositions can be prepared comprising the invention thermoplastic elastomer compositions, optionally as modified with conventional additives and adjuvents. Further, in view of the, preferred process of preparation usinj; insertion polymerization of readily available olefins, the invention thermoplastic elastomer compositions can be prepared with low cost petrc chemical feedstock under low energy input conditions (as compared to either of low temperature anionic polymerization or multistep melt processing conditions where vulcanization is needed to achieve discrete thermoplastic elastomer morphologies). EXAMPLES In order to illustrate the present invention, the following examples are provided. Such are not meant to limit the inversion in any respect, but are; solely provided for illustration purposes. General: All polymerizations were performed in a i-liter Zipperclave reacior equipped with a wate; jacket for temperature control. Liquids were measured into the reactor using calibrated sight glasses. High purity (>99.5%) hexane, toluene: and butene feeds were purified by passing first through basic alumina activated at high temperature in nitrogen, followed by 13x molecular sieve activated at high temperature in nitrogen. Polymerization grade ethylene was supplied directly in a nitrogen-jacketed line and used without further puriticalion Clear, 10% methylalumoxane (MAO) in toluene was received from AJbemarle Inc. in stainless steel cylinders, divided into 1-liter glass containers, and stored in a laboratory glove-box at ambient temperature. Ethylene was added to th: reactor as needed to maintain total system pressure at the reported levels (semi-batch operation). Ethylene flow rate was monitored using a Maiheson mass flow meter (model number 8272-0424). To ensure the reaction medium was well-mixed, a flat-paddle stirrer rotating at 750 rpm was used. Reactor preparation: The reactor was first cleaned by heating to 150°C in toluene to dissolve any polymer residues, then cooled and draimul. Next, the reader was healed using jacket water at 11O°C and the reactor was purgtd with flowing nitrogen for a period of -30 minutes. Before reaction, t3:e reactor was further purged using 10 nitrogen pressurize/vent cycles (to 100 psi) and 2 ethylene pressurize/vent cycles (to 300 psi). The cycling served three purposes: (1) to thoroughly penetrate all dead ends such as pressure gauges to purge mgitive contaminants, (2) to displace nitrogen in the system with cthylene, and (3) to pressure test the reactor. Catalyst preparation: All catalyst preparations were performed in an inert atmosphere with Macromer synthesis: First, the catalyst transfer tube was attached to a reactor port under a continuous flow of nitrogen to purge ambient air. Next, the reactor was purged and pressure tested as outlired above. Then, 600 ml of solvent wa:, charged to the reactor and heated to the desired temperature. Comononier (if any) was then added, ternperatxire was allowed to equilibrate, and the base system pressure was recorded. The desired partial pressure of ethylcne was added on top of th-j base system pressure. After allowing the ethylcne to saturate the system (as indicated by zero cthylene flow), the catalyst was injected in a pulse using high pressure solvent Reaction progression was monitored by reading ethylene uptake from the electronic mass flow meter. When the desired amount of macromer had accumulated, etiylcne flow was terminated ami the reaction was terminated by heating (- 1 minute) to 150°C for 30 minutes, At the end of the kill step, the reactor was cooled to the temperature desired for the LCB block assembly reaction (below) and a macromer sample was removed for analysis. Assembly of LCB Block Structures. All long chain branched (LCB) olefin copolymer assembly reactions were performed in toluene using ethylene at 100 psi and MAO-acrjvated (C5Mc4SiMe2NCl2H23)TiCl2 catalyst Butene was used as comonomer in most syntheses, but select reactions were performed using norbomene comonomer in order to generate samples used to quantify LCB content. Reaction was terminated by methanol injection when the desired amount of polymer (total accumulated mass) were produced. Ethylene uptake'reactor pressure drop was observed to halt within about 10 seconds of injection. The product was poured into an excess of isopropyl alcohol and evaporated to dryness. In iinother example (Example 3), CftZrCl2and (C3Me4SiMe;NCl2H23)TiCl2 catalysts were used in single-step, mixed rnetallocene syntheses where the macromcrs were prepared concurrently with the backbone and incoiporated therein. Catalysy pairing. For the mixed rrelallocene in situ example, the rnetallocene caialyst pair was selected such that both a good incorporating catalyst and a poorer incorporating catalyst was used. For this technology, the good incorporator will typically exhibit three times the incorporation capability of the poor incorporation 01, even more preferably, five times the incorporation capability. Comonomer incorporation capability is defined and measured for each catalyst compound, for the purposes of the present invention, in terms of weight percent butcue incorporation using a defined standard reaction condition as follows. A one iter autoclave reactor is purged 2 hours at 90°C with high purity nitrogen. The system is next purged of nitrogen using flowing ethylene. Next, 600 millilitcrs of toluene and 50 miliiliters of liquid butene are added. The system is allov/ed to equilibrate al 90°C. Next, ethylene at 100 psig is added until the solution is saturated. A milligram of catalyst is added to 0.5 miliiliters of 10 weight percent MAO in a stainless steel addition tube in an inctt atmosphere glovebox. Depending on the reactivity of the catalyst, more or less catalyyt/MAO solution may be required to assure substantial levels of polymerization without excessive reaction exotherms. The catalyst is injected into the reactor using pressurized solvent. Reactor pressure is maintained at 100 psig throughout reaction by adding ethylene as required. The reaction is terminated before the reactant compositions inside the reactor change substantially ( Example 1. Catalyst Preparation. A stainless steel catalyst addition tube was prepared as outlined above, An aliquot: of 1 milliliter of 10% methylalumoxane (MAO) solution in toluene was added, followed by 5 miliiliters of a toluene solution containing 16 milligrams of (C5Me4SiMe2NC12H23)TiCl2 The scaled tube was removed from the giovebox and connooted to a reactor port under a containous flow of nitrogen. A flexible, stiinlcss steel line from the reactor supply manifold was connected to the other end of the addition tube under a continuous flow of nitrogen. Macromer Synthesis. The reactor was simultaneously purged of nitrogen and pressure tested using two ethylene fill/purge cycles (to 300 psig). Then, the reactor pressure was raised to -40 psi to maintain positive reactor pressure during setup operations. Jacket water temperature was set to 90°C and 600 milliliters of toluene and 10 milliliters of butene were added to the reactor. The surrcr was set to 750 rpm. Additional cthylene was added to maintain a positive reactor gauge pressure as gas phase ethylene was absorbed into solution. The reactor temperature contt oiler was set to 90°C and the system was allowed to reach steady state. The ethylene pressure regulator was next set to 100 psig and ethylene was addec to the system until a steady state was achieved as measured by zero ethytane uptake. The reactor was isolated and a pulse of toluene pressurized to 300 psig was used to force the catalyst solution from the addition tube into the reactor. The 100 psig ethylene supply manifold was immediately opened to the reactor in order to maintain a constant reactor pressure as ethylene was consumed by reaction. After 15 minutes of reaction, the reaction solution was quickly heated to 150°C for 30 minutes, then coded to 90°C. A sample of the prepolymerized macromer was removed from the reactor. LCB Block Copolymer Synthesis. A stainless steel catalyst addition tube was prepared as outlined above. An aliquot of 0.5 milliliter of 10% methylalumcxane (MAO) solution in toluene was added to the tube, followed by 1 milli.iter of a toluene solution containing 0.5 milligrams of (C5Me4SiMe2NC12H23)TiCl2 per milliliter. The scaled tube was removed tram the gloviibox and connected to a reactor port under a continuous flow of nitrogen. A flexible, stainless steel line from the reactor supply manifold was connected to the other end of the addition tube under a continuous flow of nitrogen. The reactor temperature controller was set to 90°C. Next, 70 milliliters of butene were added to the macromer-containing reactor and the system was allowed to reach thermal equilibrium. Ethylene was next added to the system at 100 p£.ig (total). After allowing the cthylcne to saturate the system (as indicated by zero cthylenc flow), the catalyst was injected in a pulse using high pressure solvent. Reaction progression was monitored by reading ethylene uptake from the electronic mass flow meter. Reaction was terminated by methanol injection after 15 minutes. The product was poured into an excc&s of isopropyl alcohol and evaporated to dryness. Tctal yield of LCB block oopolymer was 42.6 grams, Example 2. Catalyst Preparation. A .stainless steel catalyst addition tube was prepared as outlined above. An aliquot of 0.5 milliliter of 10% methylalumoxane (MAO) soluton in toluene was added, followed by S milliliters of a toluene solution containing 8 milligrams of Cp2ZrCl2 The sealed tube was removed from the glove box and connected to a reactor port under a continuous flow of nitrogen. A flexible, stainless steel line from the reactor supply manifold was connected to the other end of the addition tube under a continuous flow of nitrogen. Macromer Synthesis. The reactor was simultaneously purged of nitrogen and pressure tested using two ethylene fill/purge cycles (to 300 psig). Then, the reactor pressure was raised to -.20 psi to maintain positive reactor pressure during setup operations Jacket water temperature was set to 90°C and 600 miliititers of toluene and 2 milliliters of 80.6 weight percent norboraene in toluene were added to the reactor. The stirrer was set to 750 rpm, Additional ethylene was added to maintain a positive reactor gaujie pressure as gas phase ethylene WAS absorbed into solution. The reactor temperature controller was set to 90oC and the system was allowed to reach steady state. The ethylene pressure regulator was next set to 30 psig and ethylene was added 1:0 the system until a steady state was achieved as measured by zero ethyiene uptake. The reactor was isolated and a pulse of toluene pressurized to 300 psig was used to force the catalyst solution from the addition tube into the reactor. The 30 psig ethylene supply manifold was immediately opened to the realtor in order to maintain a constant reactor pressure as ethylene was consumed by reaction. After 15 minutes of reaction, the reaction solution was quickly hefited to 150°C for 30 minutes, then cooled to 90°C. A sample of the prepolymerized macrDmer was removed from the reactor. LCB Block Copolymer Synthesis. A stainless steel catalyst addition tube was prepared ,is outlined above. An aliquot of 0.5 milL'liter of 10% methylalumoxane (MAO) solution in toluene was added, followed by \ milliliter of a toluene solution containing 1 milligram of (C5ME4SiMe2C12H23)TiCl2 per mill) liter. The sealed rube was removed from the glovebox and connected to a reactor port under a continuous flow of nitrogen. A flexible, stainless steel line from the reactor supply manifold was connected to the other end of the Jiddition tube under a continuous flow of nitrogen. The reactor temperature controller was s«t to 60°C. Next,60 millliters of 80.()% norbornene in toluene were added and the system was allowed to reach thermal equilibrium. Ethylene was next added to the system at 100 psig (total). After allowing the ethylene to saturate the system (as indicated by zero ethylene flow), the catalyst was injected in a pulse using high pressure solvent. Reaction progression was monitored by reading ethylene uptake from the electronic mass flow meter. Reaction was terminated by melhanol injection after 5 minuses. The prcduct was poured into an excess of isopropyl alcohol and evaporated to dryness. Total yield of LCB block copolymer was 91.9 grams. Example 3. Catalyst Preparation. A stainless sttcl catalyst addition tube was prepared as ouilined above. An aliquot vif 1 millilliter of 10% methylalunoxane (MAO) solution in tolune was added, rbilowed by a toluene solution containing 0.25 milligram of (C3Me4SiMe2NC12H23)TiCl2 and 5 micrograms of Cp2ZrCl2. the scale, tube was removed from the giovebox and connected to a reactor port under a continuous How of nitrogen. A flexible, stainless steel line from the reactor supply manifold was connected to die other end of the add it-on tube under a continuous flow of nitrogen. In tint LCB Block Copolyraer Syn.hesis. The reactor was simultaneously purged ofn.tregen and pressure tested using two ethylene fill/pure cycles (to 3(10 psig) Then, the reactor pressure was raised to -40 psi to maintain positive reactor pressure during setup operations Jacket water temperature was set to 90oC and 600 milliliters of toluene and 20 millitrs butcne were added to the reactor The stirrer was set. to 750 rprr.. Additional ethylene was added to maittain a positive reactor gauge pressure as gas phase ethylene was absorbed into solution. The reactor temperature controller was set to 90oC and the system was allowed to reach steady state. the ethylere pressure regulator was next set to 100 psig and ethylene was added to the system until a steady state was achieved as measured by zero ethylene up take. The reactor was isolated and a pulse of toluene pressurized to 300 psig; -A.,; used to 'ore: the catalyst solution from the addition tube into the reactor. The 100 psig ethylene supply manifold immediately opened to the reactor in order to maintain a constant reactor pressure as ethylene was consumed by reaction Reaction was terminated by methanol injection after7 minutes. The product was poured imc an excess of isopropyl alcohol and evarorated to dryness Total yield of LCB block copolymer was 18.5 grams. Propeties. structual data for the select materials are listed in Table in thecase of the first two elas.omeric examples (1 and 2}, the macromer was sampled directly from the reactor and characterized by 'H-NMR and GPC, while for example (mixed metallecne synthesis), the properties o 'the macromer and backbone were attributed from the corresponding single metallocene reactions. Tensile data were obtained at room temperature and 80'C according to method ASTM 3-14 (in Figure 1, tensile strength at break at room temperature •and 80oC is reported in units of pounds per square inch while elengation as break is reported as a percentage). Recovery was measured at room temperature using sample specimens identical to those used in ASTM D-14 test except the sample was stretched 1:50°/o. tlien released for 10 minutes and the percent recovered to the orginal dimensions measures directly using reference marks en the test sample. Tensile data for select sample indicate the statistically branched LCB block.-copolymer. Formulation exhibited tensile strengthswhich commercially useful limits (see Table 1 and Figure 1). Tensile strength at break is highest for the norbornene LCB block copolymer (4,011psi) whereas the best elastic recovery (89%) was observed in a mixed –metallocene butane LCB block copolymer . both the low molecular weight (10K. Cp2ZrCl2 catalyzed) and high Mn (30-40K) (C5Me2NC12H23)TiCl2-catalyzed) macromer gave LCB block copolymers with useful properties The ethylene butane LCB block copolymers exhibit elastomeric properties superior to an EXACT 4033 ( Exxon chemical company ) ethylene/butane E/B) rardom copolymer of similar density and equal or better to an ENGAGE 8100 (DOW Chemical Company) ethylene/octane (E/O)random copolymer of similar Comonomer conectrations can be increased further by decreasing the concentration of ethylene in solution (by decreasing ethylene partial pressure or increasing temperature.) Table 2Comparision of Branch copolymer Properties Representative LLDPE’S Propen j- Branch Branch Branch ENGAGE'5 TiXACT* copo.ymer copolymer c.opolymer 8 IOC 4033 E/B(#1; F/NB (#1) !:/B (#3) n/o K/B Dens cv (g/m ) 0,887 >0,935 .887 0.8"0 0.880 ASTMD-1505 Com (mol'-i 'HNMR) Melt: ng Point 119.2 115.:'. 123.5 r W 63 (°C. DSC ) Tensile at B'eak 2401 ^ 4011 3054 io:m 1 1780 psi (kPa), (16.50C) (27,700) (21,000) V.IOO) (12,300) ASTMD-412 Elongation at 905 I 386 669 950 740 Break (%) ASTMD-412 Recover-- (%) 76 60 87 76 50 150C'> extension Note : E - ethylene, B = butene, NB =norbomene. and O = octene. Table3. Comparsion of Branch Copolymer Properties with commercial styrene Triblock Copolymer (Fig.1 (Table Removed) density (Table 2)Comparison of the ethyle:ie/norbornene (E/NB) linear and E/NB l.CH bled; counterparts indicate the LCE block copolymer is somewhat at • defensive in MOST areas, due in part to it much lower norbomene content Of course all of the LCH block copolymcrs neli at much higher temperatures than their linear counterparts due to the crystallizable low molecular weight branch component. It is component It is interesting to note that the LCB block copolymers retain signification tensile strength even when healed above the melt temperature of their amorohous component (see 80°C tensile data). The observed high temperature strength may be due to multi-block-type networks in which amorphous material is anchored to high density', high melting zones by fide chains. Product characterization The branched olefin copolymer product sample were analyzed by GPC using a Waters 1:50C high temperature system equipped with a DRI Detector, Shodex AT-806V.S column and operating at a system temperature 45oC. The solvent used \vas 1,2,4 trichlorobeii2:er.e, from which polymer sample solutions of 0.1 mg/ml concentration were prepared for injection The total solvent flow rate was 1.0 ml/minute and the injection size was 300 microliters GPC columns v\ere calibrated using a series of narrow polystyrenes '(obtained from Tosoh Corporation, Tokyo, 1989). For quality control a broad-standard calibration ba5ed on the linear PE sample NBS-1475 v/as used. The standard was run with each l(;.-vial carousel. It was injected twice as the first sample of each batch. After elution of the polymer sample, the resulting chromatograms were analyzed using the Waters Expert Ease program to calculate the molecula- weight distribution and Mn Mw and M2 average Polymer Analyses. The molecular weight , comonomer content, and unsaturated- group structural distributions of the reaction products are reported in Table2. Unsaturated group concentrations (total olefins per1,00carbon atoms) as well as vinyl group selectivities were found to increase with decreasing aluminum metal ratios, all other factors being equal. The reported olefin WE CLAIM: 1. A process for the preparation of a thermoplastic elastomer composition comprising the steps of: A] copolymerizing by contacting ethylene, optionally with one or more copolymerizable monomers selected from the group consisting of C3-C20 alpha olefins, germinally disubstituted monomers, C5-C25 cyclic olefins, styrenic olefins, C3-C8 alkyl substituted analogs of C5-C25cyclic olefins, and C3-C8 alkyl substituted analogs of styrenic olefins, with an activated transition metal metallocene olefin polymerization catalyst of the kind such as herein described, in a polymerization reaction at a temperature from 20°C to 200°C to form a copolymer having greater than 40% chain end-group unsaturation; B] copolymerizing the product of Step A) with ethylene and one or more copolymerizable monomers so as to prepare said thermoplastic elastomer, wherein the thermoplastic elastomer comprises a branched olefin copolymer comprising: i] sidechains with number-average molecular weight greater than 10, 000 and less than 45, 000, a Tg as measured by DSC less than or equal to 10°C; and Tm greater than 80°C; ii] elastomeric backbone polymeric segments having a Tg as measured by DSC less than or equal to -10°C; iii] an elongation at break of greater than or equal to 300%; iv] a Tensile strength of greater than or equal to 1,500 psi (10,300 kPa); and v] an elastic recovery of greater than or equal to 50%, wherein the mass of the elastomeric backbone segments comprise 40 wt% to 60 wt% of the total polymer mass. 2. The process as claimed in claim 1, wherein said branched olefin copolymer comprises sidechains derived from ethylene, optionally with one or more copolymerizable monomers, wherein the Tg of the sidechains is less than -10°C. 3. The process as claimed in claim 1, wherein said branched olefin copolymer has sidechains derived from propylene, optionally with one or more copolymerizable monomers, wherein the Tg of the sidechains is less than -10°C, and the T m is greater than or equal to 110°C. 4. The process as claimed in claim 1, wherein step A) is conducted by a solution process having a hydrocarbon solvent, in which said ethylene and one or more copolymerizabe monomers are contacted with a transition metal metallocene olefin polymerization catalyst activated by an alumoxane cocatalyst, and wherein the mole ratio of aluminum to transition metal is less than 220:1. 5. The process as claimed in claim 4, wherein step B) is conducted in a separate reaction by solution, slurry or gas phase ethylene polymerization with an activated transition metal insertion polymerization catalyst. 6. The process as claimed in claim 1, wherein step A) and B) are conducted concurrently in the presence of a mixed catalyst system having one transition metal olefin polymerization catalyst capable of preparing ethylene copolymers having greater than 40% chain end-group unsaturation and at least one transition metal olefin polymerization catalyst capable of incorporating the ethylene copolymers into said branched olefin copolymer. 7. The process substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Full Text

The present invention relates to a process for the preparation of a thermoplastic elastomer.
Technical Field
The invention relates to thermoplastic elastomer composition comprised of branched olefin copolymers having crystallizable polyolefin sidechains incorporated into low crystallinity polyethylene backbones.
Background Art
Triblock and multi-block copolymers are well-known in the art relating to elastomeric polymers useful as thermoplastic elastomer ("TPE") compositions due to the presence of "soft" (elastomeric) blocks connecting "hard" (crystallizable or glassy) blocks. The hard blocks bind the polymer network together at typical use temperatures. However, when heated above the melt temperature or glass transition temperature of the hard block, the polymer flows readily exhibiting thermoplastic behavior. See, for example, G. Holden and N.R. Legge, Thermoplastic Elastomers: A Comprehensive Review, Oxford University Press (1987).
The best commericially known class of TPE polymers are the styrenic block copolymers (SBC), typically linear triblock polymers such as styrene-isoprene-styrene and styrene-butadiene-styrene, the latter of which when hydrogenated become essentially styrene-(ethylene-butene)-styrene block copolymers. Radial and star branched SBC copolymers are also well-known. These copolymers typically are prepared by sequential anionic polymerization or by chemical coupling of linear diblock copolymers. The glass transition temperature (T g)of the typical SBC TPE is equal to or less than about 80-90°C,_

thus presenting a limitation on the utility of these copolymers under higher temperature use conditions. See, "Structures and Properties of Block Polymers and Multiphase Polymer Systems: An Overview of Present Status and Future Potential", S. L. Aggarwal, Sixth Biennial Manchester Polymer Symposium (UMIST Manchester, March 1976)
Insertion, or coordination, polymerization of olefins can provide economically more efficient means of providing copolymer pioducts, both because of process efficiencies and feedstock cost differences. Thus useful TPE polymers from olefmically unsaturated monomers, such as ethylene and C3-C8 α olefins, have been developed and are also well-known. Example;, include the physical blends of thermoplastic olefins ("TPO") such as polypropylene with ethylene-propylene copolymers, and similar blends wherein die ethylene-propy ene, or ethylene-propylene -diolefm phase is dynamically vulcanized so as to maintain well dispersed, discrete soft phase particles in a polypropylene matrix. See, N.R. Legge, "Thermoplastic elastomer categories: a comparison of physical properties". ELASTOMERICS. pages 14-20 (Sept., 1991), and references cited therein.
The use of metallocene catalysts for olefin polymerization has led to additional contributions to the field. U.S. patent 5,391,629 describes thermoplastic elastomer compounds comprising tapered and block linear polymers from ethylene ard alpha-olefin monomers. Polymers having herd and soft segments arc said to be possible with single site metallocene catalysts that are capable of preparing both segments. Examples are provided of linear thermoplastic elastomers having hard blocks of high density polyethylere or isotactic polypropylene and soft blocks of ethylene-propylene rubber. Japanese Early Publication H4-337308(1992) describes what is said to be .1 polyolefk copolymer product made by polymerizing propylene first so as to form an isotactic polypropylene and then copolymerizing the polypropylene with ethylene and

propylene, both polymerization in the presence of an organoaluminum compound and a silicon-bridged, biscyclopentadienyl zirconium dihalide compound.
Datta, et al (D.J. Lohse, S. Datta, and E.N. Kresge, Macromolecules 24, 561 (1991) described EP backnbones functionalized with cyclic diolefins by terpolymerization of ethylene, propylene and diolefin. The statistically functionalized EP "soft bloc" was then copolymerized with propylene in the presence of a catalyst producing isotactic polypropylene. In this way, some of the "hard" block polypropylene chains were grafted through the residual olefinic unsaturatuion onto the EP "soft" block as they were formed. See also, EP-A-0 366 411. A limitation of this class of reactions, in which chains with multiple functionalities are used in subsequent reactions, is the formation of undesirable high molecular weight material typically referred to as gel in the art, U.S. patent 4, 999, 403 describes similar graft copolymer compounds where functional groups in the EPR backbone are used for grafting isotactic polypropylene having reactive groups. In both the graft copolymers are said to be useful as compatibilizer compounds for blends of isotactic polypropylene and ethylene-propylene rubber.
Summary of the Invention
Accordingly, there is provided a process for the preparation of a thermoplastic
elastomer composition comprising the steps of:
A] copolymerizing by contacting ethylene, optionally with one or more
copolymerizable monomers selected from the group consisting of C3-C20 alpha
olefins, germinally disubstituted monomers, C5-C25 cyclic olefins, styrenic
olefins, C3-C8 alkyl substituted analogs of C5-C25 cyclic olefins, and C3-C8 alkyl
substituted analogs of styrenic olefins, with an activated transition metal
metallocene olefin polymerization catalyst of the kind such as herein described,
in a polymerization reaction at a temperature from 20°C to 200°C to form a
copolymer having greater than 40% chain end-group unsaturation;
B] copolymerizing the product of Step A) with ethylene and one or more
copolymerizable monomers so as to prepare said thermoplastic elastomer,

wherein the thermoplastic elastomer comprises a branched olefine copolymer comprising:
i] sidechains with number-average molecular weight greater than 10, 000
and less than 45, 000, a T g as measured by DSC less than or equal to 10°C; and Tm greater than 80°C;
ii] elastomeric backbone polymeric segments having a T g as measured by DSC less than or equal to -10°C;
iii] an elongation at break of greater than or equal to 300%;
iv] a Tensile strength of greater than or equal to 1,500 psi (10,300 kPa); and
v] an elastic recovery of greater than or equal to 50%, wherein the mass of the elastomeric backbone segments comprise 40 wt% to 60 wt% of the total polymer mass.
Brief Description of Figures
Fig. 1 illustrates a comparison of measured physical properties of branched olefin copolymers of the invention with a commercially available styrene block copolymer thermoplastic elastomer.
Detailed Description of the Invention
The thermoplastic elastomer compositions of this invention are comprised of branched copolymers wherein both the copolymer backbone andpoymeric sidechains are derived from monoolefins polymerized under coordination or insertion conditions with activated transition metal organometallic catalyst compounds. The sidechains are copolymerized so as to exhibit crystalline, semi-crytalline, or glassy properties suitable for hard phase domains in accordance with the art understood meaning of those terms and are attached to polymeric backbone that is less crystalline or glassy than the sidechains, preferably, substantially amorphous, so as to be suitable for the complementary soft phase domains characteristic of thermoplastic elastomer compositions.

The cryjtalli/able sidechains are comprised of chemical units capable of forming crystalline or glassy polymeric segments under conditions of insertion polymerization. Known monomers meeting this criteria are ethylene, propylene, 3-mi:thyi-l-pentene, and copolymers thereof, including ethylene ccpolymers with α-ohfm, cyclic olefm or styrcnic comonomers. Ethylene or propylene copolymcr sider.hains are preferable provided that the amount of comonomer is insufficient to disrupt the crystallinity such that the Tm is reduced below 80°C. Suitable comonomers include C3-C20 α-olefins or geminally disubstituted monomers, C5-C25 cyclic clef ins, styrenic olefins and lower carbon number (C3-C8) alkyl-substiuted analogs of the cyclic and styrenic olefins. Thus, typically, the sideohains can comprise from 85-100 rnol% elhylene, and from 0-15 mol% comonomer, preferably 90 -99 mol% ethylene and 1-10 mol% comonomer, most preferably 94 -98 mol% ethylene and 2-6 mol% comonomer. Alternatively, the sidechains can comprise from 90-100 mol% propylene, and from 0-10 mol% comonomer, preferably 92-99 rnol% propylene and 1-8 mol% comonomer, most preferably 95-98 mol% propyler e and 2-5 mol'/o comonomer. In particular, as the sidecnain Mn increases above about 3,0[)0, it is preferable to introduce small amounts of comonomer to minimize embrittlement, e.g., about 0.2 - 4.0 mol.% comonomer, The selection of comonomer can be based upon properties other than cryslallinitv dismpting capability, for instance;, a longer olefin comonomer, such as 1-octene, may be preferred over a shorter olefm such as 1-butenc for improved polyethylene film tear. For improved polyethylene film elasticity or barrier properties, a cyclic comonomer such as lorbornene or aliyl-sub.stituted norbirnene may be preferred over an a-olefin.
The sidechains can have narrow or broad molecular weight distribution (Mw/Mn) for example, from 1.1 to 30. typically 2-8. Additionally, the sidechains can have different commonoer compositins, e.g., including the orthogonal compositional cistributions described in U.S. patent 5,382,630 (CDBI >50%),

incorporated by reference for purposes of U. S. patent practice. Optionally, mixtures of sidcchains with different molecular weights and/or compositions may be used.
The Mn of the side-chains are within the range of from greater than or equal to 1 500 and less than or equal to 45,000 Preferably the Mn cf the sidechains is from 1,500 to 30,000, and more preferably the Mn is from 1,500 to 25,000. The number of sidechains is related to the Mn of 'he sidechains such that the total weight ratio of the weight of the sidechains to the total weight of the polymeric backbone segments between and outside the incorporated sidechains is less than 60%, preferably 40-50%. Molecular weight her: is determined by gel permeation chromatography (GPC) and differential refractive index (DRI) measurements. A preferred branched olefiaic copolymer within this class will have an enthalpy of fusion (Hf) a measured by differential scanning calorimetry of ≤ 90 cal/g (meaured by integrating heat flows recorded at temperatures 5 80 °C while scantling at ≥ 5 oC/min).
The backbone, or backbone polymeric segments, when taken together with the sidechain interruption of the backbone structure, should have a lower Tn, (or Te if not exhibiting a Tm) than the sidechains. Thus it will preferably comprise segments of chemical units not having a measurable crystallinity, or having a Te lower than -10 °C. The backbone segments as taken together typically will have a Tm less than or equal to 80 °C and a Tg less than or equal to -10 °C. Elastomeric backbones will be particularly suitable, such will be typically comprised of ethylene and one or more of C3-C12 α-olcfms or diolefins, particularly prcpylene and 1-buteiie. Other copolymerizable monomers include geminally disubstituted olefirus such as isobutylene, cyclic olefins such as cyclopentene, norbornene and alkyl-substitutec norbornenes, and styrenic monomers such as styrcne and alkyl substituted styrenes. Low crystallinity backbones are suitable, examples are high

comonomer content ethylene copolymers (as described before), e.g., > than 8 mol% comonomer.
As indicated aboe the mass of the backbone will typically comprises at least 40 wt% of the total polymer mass, that of the backbone and the sidechains together, so the backbone typically will have a nominal weight-average molecular weight (Mw) weight of at least equal to or greater than about 50,000. The term nominal is used to indicate that direct measurement of Mw of the backbone is largely impossible but that characterization of the copolymer product will exhibit measurements of Mw that correlate to a close approximate weight of the polymeric backbone inclusive only of the monoolefin mer derivatives and the insertion moieties of the sidebranches.
The branched olefin compolymers comprising the above sidechains and backbones will typically have an Mw equal to or greater than 50,000 as measured by GPC/DRI as defined for the examples. The Mw typically can exceed 300, 000, preferably 200, 000, up to 500, 000 or higher.
The thermoplastic elastomer composition of the invention can be prepared by a process comprising : A) copolymerizing ethylene or propylene, optionally with one or more copolymerizable monomers, in a polymerization reaction under conditions sufficient to form a copolymer having greater than 40% chain end-group unsaturation, a Tm≥800C and a Tg ≤10°C; B) copolymerizing the product of A) with ethylene and one or more copolymerizable monomers so as to prepare said branched olefin copolymer. For ethylene-based macromers prepared in step A), the Tgpreferably less than -5°C, more preferably less than -10°C.
Accordingly, in a preferred embodiment, the branched olefin copolymer of the present invention comprises sidechains derived from propylene, optionally with one or more copolymerizable monomers, such that the Tg of the sidechains is less than -10°C, and the Tm is greater than or equal to 110°C.
The process step A) can be usefully practiced in a solution process in which ethylene and, optionally, one or more copolymerizable monomers, is contacted with a transition metal olefin polymerization catalyst activated by an

alkylulumoxane cocatalyst, the mole ratio of aluminum to transition metal being less than about 220:1. The terminally unsnturated copolymer population so formed, with or without separation from copolymer product having only saturated ends, can then be copolymerized with ethylenc and copolymcrizablc monomers in a separate reaction by solution, slurry or gas phase cthyiene polymerization with an activated transition metal insertion polymerization catalyst, particularly a catalyst capable of incorporating the cthyiene copolymers into said brzmched olefin copolymer.
Alternatively, the process step A) can be practiced in a solution process in which propylene and, optionally, one or more copolyrnerizable monomers, is contacted with a stereorigid transition metal olefin polymerization catalyst, one capable of producing stereregular polypropylene, activated by any suitable cocatalyst, the reaction temperature kept at sufficiently high levels so as to achieve significant populations of terminally unsaturated polymer chains, e.g;., greater than about 85 °C, preferably greater than about 90 °C. The terminally unsaturated copo ymer population so formed, with or without separation from copolymer product having only saturated ends, can then be copolymerized with ethylene and copoiymerizable monomers, or other selection of monomers suitable for the prepfiration of low crystallinity polymers, in a separate reaction by solution, slurry or gas phase ethylene polymerization with an activated transition metal insertion polymerization catalyst, particularly a catalyst capable of incorporating the propylene copolymers into said branched olefin copolymer having the low crystellinity backbone.
Conditions sufficient to form the sidediain ethylene copolymer include using; suitable ethylene and comonomer reactant ratios to assure the described
sidechain olefin-derived unit constitution, plus catalyst and process conditions
conducive to fomiing the unsasurated chain ends. The teachings of copending provsional application U.S. Ser. No. 60/037323 filed 02/07/97 are specific to

suitable catalyst selection and use to prepare raacromeric copolymer chains with a high yield of vinyl unsaturation. The raetallocene catalyst used in the step A) preparation of the unsaturation-cntaining macromcr can be essentially any catalyst capable of insertion polymerization of ethylene, it can be one capable of high comonorner incorporation capability (sec below) or of low comoriomcr incorporation capability. Those of low incorporation capability are typically those that are more congested at the metal coordination site, thus unbridged and substituted unbridged metallocene catalysts are particularly suitable. See also the teachings of U.S. Patent 5,498,809 and international publications WO 94/19436 and V'O 94/13715, describing means of preparing vinylidene-tcnninated ethylene-l-butcne copoly-ners in high yields. Sec also, the teachings of copending application U.S. Ser. No. 08/651,030, filed 21 May 1996, as to the preparation of ethylene-isobutylenc copolymer; having high levels of vinylidene chain-end unsatoration. Throughout the description above, and below, the phrase "chain-end" or "terminal" when referring to unsaturution means olefin unsatiiration buitablc for insertion polymerisation whether or not located precisely at the terminus of a chain. Sec also U.S. paten:s 5,324,801 and 5,621,054 addressing alternating ethytene-cyclic olefin copolymers having crystalline melting points of 235 °C, and up, macromers produced with the suitable catalysts of these descriptions will have glassy attributes effective for functioning as the hard phase component of the thermoplastic elastomers of this invention. All documents of this paragraph ore incorporated by reference for purposes of U.S. patent practice.
In a particular embodiment, polymeric vinyl-containing, ethylene-contuning ma;romer product, suitable as branches for a subsequent copclymerization reaction, can be prepared under solution polymerization conditions wilh preferred molar ratios of aluminum in the alkyl aluraoxane activator, e.g.. methly almoxane (MAO), to transition metal. Preferably that level is ≥ 20 and ≤175; more preferably ≥ 20 and ≤ 140; and. most preferably ≥ 20 and ≤ 100. The temperature, pressure and time of reaction depend upon the selected

process but are generally within the normal ranges for a solution process. Thus temperatures can range from 20°C to 200°C, preferably from 306C to 150oC, and more preferably from 50°C to 140°C. The pressures of the reaction generally can vary from atmospheric to 345 MPa, preferably to 182 MPa, For typical solution rcacti nns, temperatures will typically range from ambient to 190 °C with pressures from ambient lo 3.45 MPa. The reactions can. be run batchwise. Conditions for suitable slurry-type reactions are similar to solution conditions except reaction temperatures are limited to those below the melt temperature of the polymer. In an additional, alternative reaction configuration, a supercritical fluid medium can be used with temperatures up to 250°C and pressures up to 345 MPa. Under high temperature anc pressure reaction conditions, macromer product of lower mole:ular weight ranges are typically produced, e.g., Mn about 1,500-.
In an alternative embodiment, polymeric vinyl-containing, propylene-containing macromer product, suitable as branches for a subsequent
copolymerization reaction, car. be prepared under solution polymerization conditions with metallocsne catalysts suitable for preparing either of isotactic or syndiotactic polypropylene. A prefcired reaction process ibr propylenc maciomers having high levels of terminal vinyl unsaturation is described in co-pending U.S. application 60/ 067,783, filed December 10, 1997, Attorney Docket No. 97B075. Typically used catalysts are stereorigid, chiral or asymmetric, bridged metal lccenes. See, far example, U.S. patent 4,892,851, U.S. patent 5,017,714, U.S. patent 5,132,281, U.S. patent 3,155,080, U.S. patent 54W34, U.S. patent 5.278,264, U.S. patent 5,318,935, WO-A-(PCT/US92/10066), WO-A-93/19103, EP-A2-0 577 581, EP-A1-0 578 838, and academic literature "The Influence of Aromatic Substitusnts on the Polymerization Behavior of Bridged Zirconocene Catalysts", Spaleck. W., et al, Organometallics 1994, 13, 9:54-963, and "ansa-zirccnocene Polymerization Catalysts with Annelared Ring Ligands-Effects on Catalytic Activity and Polymer Cham Lengths", Rrinzinger, H., et al, Organometallcy 1994, 13,964-370, and documents referred to therein.

Preferably, for isotatic polypropylene, the stereorigid transition metal catalyst compound is selected from the group consisting of bridged bis(indcnyl) zirconoccncs or hafnocenes. In a preferred embodiment, the transition metal catalyst compound is a dimcthylsilyl-bridged bis(indenyl) zirconocene or hafnocene. More preferably, the transition metal catalyst compound is dimelhylsilyl (2--methyl-4-phenylindenyl) zirconium or hafniumdichloride or dimelhyl. In another preferred embodiment, the transition metal catalyst is a dimcthylsilyl-bridged bis(indcnyl) hafnocene such as dimethylsiiyl bis(indenyl)hafnium dimethyl or dichloride. The method for preparing propylene-based maeromers: having a high percentage of vinyl terminal bonds involves:
a) contacting, in solution, propyicne, optionally a minor amount of
copolymerizable monomer, with a catalyst composition containing
the stereorigid, activated transition metal catalyst compound at a
temperature from about 90°C to about 120°C; and
b) recovering isotactic or syndiotacuc polypropylene chains having
number average molecular weights of about 2,000 to about 150,000
Daltons.
Preferably, the solution comprises a hydrocarbon solvent. More preferably, the hydrocarbon solvent is aromatic. Also, the prcpylenc monomers are preferably contacted at a temperature from 95oC to 115°C. More preferably, a temperature from 100CC to 110°C is used. Most preferably, the propylene monomers are contacted at a temperature ftom 105oC to 110°C. The pressures of the reaction generally can vary from atmospheric to 345 MPa, preferably to 132 MPa The read ions can be run batchwise or continuously. Conditions for suitable slurry-type reactions will also be suitable and arc similar to solution conditions, the

polymerization typically being run in liquid propylene under pressures suitable to such. All documents are incorporated by reference for purposes of U.S. patent practice.
Additionally the invention branched olefin copolymer thermoplastic elastomer composition can be prepared directly from the selected clefins concurrently in t!\e presence of a mixed catalyst system comprising at leajt one first transition metal olefin polymerization catalyst capable of preparing ethylene or propylene copolymers having greater than 40% chain end-group unsatwation and at least one second transition metal olefin polymerization catalyst capable of incorporating the ethylene or propylene homopolymcr or copolymer sidechains into said branched olefin copolymer. This in situ method can be practiced by any method that permits both preparation of unsaturaled macromers having crystalline, semi-crystalline or glassy properties and copolymerization of the nracromers with comonomers constituting the low crystallinitybackbnoe such that the branched copolymer is prepared. Gas phase, slurry and solution processes can bs used under conditions of temperature and pressure known to be useful in such processes.
Suitable first catalyst compounds that when activated car achieve high chain-end unsatiarations specifically include those identified above with respect to the preparation of high vinyl or vinylidene-containing macromers. Preferably, catalysts that are active for ethylene homopolymerization but do not incorporate higher carbon number monomers appreciably as discussed above, or do :so only with attendant decrease in Mn, will be particularly suitable for the crystalline or glassy sidechaiii preparation in :he concurrent, or in situ, methoci of preparing the invention thermoplastic copolymer compositions of the invention, so long as the Mn can be raised or maintained above the sidechain minimium.

Suitable second catalyst compounds include those that are capable of good comonomcr incorporation without significant depression in Mn for the polymeric backbone under the temperature and pressure conditions used. The teachings of copending provisional application U.S. Scr. No. 60/037323 filed 02/07/97 are specific to suitable catalyst selection and us.e to prepare branched olefin copolymers and addresses catalyst compounds suitable for high comonomcr and macromonomer incorporation. As indicated therein, preferred catalyst compounds for assembling the branch olefin copolymers from vinyl- or vinylidene containing macrnmers, ethylene and copolymerizable comonomers include the bridged biscyclopentadienyl and monocyclopentadienyl Group 4 metal compounds of U.S. patents 5,198,401, 5,270,393, 5,324,801, 5,444,145, 5,475,075, 5,635,573, International applications WO92/00333 and WO 96/00244; see also the unbridged monoeyclopentadienyl Group 4 metal compounds of copending application 08/545,973, filed 10/20/95, and the bis-amido and bis-arylamido transition metal catalysts of U.S. patent 5,318,935 and copending U.S. patent application 08/ 803,(i87, filed 2/24/97, and the a-diimine nickel catalyst complexes of WO 96/2J010. In accordance • with these teachings, the transition metal catalyst comjKiunds are typically used with activating co-catalyst components as described, e.g., alky I alumoxanes and ionizing compounds capable of providing a stabilizing non-coordinating anion. The teachings of each of the documents of this paragraph arc also Incorporated by reference for purposes of U.S. patent practice.
Industrial Applicability
The theimoplastic elastomer compositions according to the invention will have- use in a variety of applications wherein other thermoplastic elastomer composition have found use. Such uses include, but are not limited to. those known tor the styrene block copolymers, e.g., styrene-isopretie-styrene and styrsne-butadiene-styrene copolymers, and their hydrogenatec analogs. Such

include a variety of uses such as backbone polymers in adhesive compositions and molded articles These applications will benefit from the increased use temperature range, typically exceeding the 80 - 90 °C limitation of the SBC copo ymer compositions. The compositions of the invention will also be suitable as compatibilizer compounds for polyolefin blends. Additionally, due to the inhcre nt tensile strength, elasticity, and ease of melt processing, extruded film, coating and packaging compositions can be prepared comprising the invention thermoplastic elastomer compositions, optionally as modified with conventional additives and adjuvents. Further, in view of the, preferred process of preparation usinj; insertion polymerization of readily available olefins, the invention thermoplastic elastomer compositions can be prepared with low cost petrc chemical feedstock under low energy input conditions (as compared to either of low temperature anionic polymerization or multistep melt processing conditions where vulcanization is needed to achieve discrete thermoplastic elastomer morphologies).
EXAMPLES
In order to illustrate the present invention, the following examples are provided. Such are not meant to limit the inversion in any respect, but are; solely provided for illustration purposes.
General: All polymerizations were performed in a i-liter Zipperclave reacior equipped with a wate; jacket for temperature control. Liquids were measured into the reactor using calibrated sight glasses. High purity (>99.5%) hexane, toluene: and butene feeds were purified by passing first through basic alumina activated at high temperature in nitrogen, followed by 13x molecular sieve activated at high temperature in nitrogen. Polymerization grade ethylene was supplied directly in a nitrogen-jacketed line and used without further puriticalion Clear, 10% methylalumoxane (MAO) in toluene was received from

AJbemarle Inc. in stainless steel cylinders, divided into 1-liter glass containers, and stored in a laboratory glove-box at ambient temperature. Ethylene was added to th: reactor as needed to maintain total system pressure at the reported levels (semi-batch operation). Ethylene flow rate was monitored using a Maiheson mass
flow meter (model number 8272-0424). To ensure the reaction medium was well-mixed, a flat-paddle stirrer rotating at 750 rpm was used.
Reactor preparation: The reactor was first cleaned by heating to 150°C in toluene to dissolve any polymer residues, then cooled and draimul. Next, the reader was healed using jacket water at 11O°C and the reactor was purgtd with flowing nitrogen for a period of -30 minutes. Before reaction, t3:e reactor was further purged using 10 nitrogen pressurize/vent cycles (to 100 psi) and 2 ethylene pressurize/vent cycles (to 300 psi). The cycling served three purposes: (1) to thoroughly penetrate all dead ends such as pressure gauges to purge mgitive contaminants, (2) to displace nitrogen in the system with cthylene, and (3) to pressure test the reactor.
Catalyst preparation: All catalyst preparations were performed in an inert atmosphere with Macromer synthesis: First, the catalyst transfer tube was attached to a reactor port under a continuous flow of nitrogen to purge ambient air. Next, the reactor was purged and pressure tested as outlired above. Then, 600 ml of solvent wa:, charged to the reactor and heated to the desired temperature. Comononier (if any) was then added, ternperatxire was allowed to equilibrate, and the base system

pressure was recorded. The desired partial pressure of ethylcne was added on top of th-j base system pressure. After allowing the ethylcne to saturate the system (as indicated by zero cthylene flow), the catalyst was injected in a pulse using high pressure solvent Reaction progression was monitored by reading ethylene uptake from the electronic mass flow meter. When the desired amount of macromer had accumulated, etiylcne flow was terminated ami the reaction was terminated by heating (- 1 minute) to 150°C for 30 minutes, At the end of the kill step, the reactor was cooled to the temperature desired for the LCB block assembly reaction (below) and a macromer sample was removed for analysis.
Assembly of LCB Block Structures. All long chain branched (LCB) olefin copolymer assembly reactions were performed in toluene using ethylene at 100 psi and MAO-acrjvated (C5Mc4SiMe2NCl2H23)TiCl2 catalyst Butene was used as comonomer in most syntheses, but select reactions were performed using norbomene comonomer in order to generate samples used to quantify LCB content. Reaction was terminated by methanol injection when the desired amount of polymer (total accumulated mass) were produced. Ethylene uptake'reactor pressure drop was observed to halt within about 10 seconds of injection. The product was poured into an excess of isopropyl alcohol and evaporated to dryness. In iinother example (Example 3), CftZrCl2and (C3Me4SiMe;NCl2H23)TiCl2 catalysts were used in single-step, mixed rnetallocene syntheses where the macromcrs were prepared concurrently with the backbone and incoiporated therein.
Catalysy pairing. For the mixed rrelallocene in situ example, the rnetallocene caialyst pair was selected such that both a good incorporating catalyst and a poorer incorporating catalyst was used. For this technology, the good incorporator will typically exhibit three times the incorporation capability of the poor incorporation 01, even more preferably, five times the incorporation capability. Comonomer incorporation capability is defined and measured for each catalyst

compound, for the purposes of the present invention, in terms of weight percent butcue incorporation using a defined standard reaction condition as follows. A one iter autoclave reactor is purged 2 hours at 90°C with high purity nitrogen. The system is next purged of nitrogen using flowing ethylene. Next, 600 millilitcrs of toluene and 50 miliiliters of liquid butene are added. The system is allov/ed to equilibrate al 90°C. Next, ethylene at 100 psig is added until the solution is saturated. A milligram of catalyst is added to 0.5 miliiliters of 10 weight percent MAO in a stainless steel addition tube in an inctt atmosphere glovebox. Depending on the reactivity of the catalyst, more or less catalyyt/MAO solution may be required to assure substantial levels of polymerization without excessive reaction exotherms. The catalyst is injected into the reactor using pressurized solvent. Reactor pressure is maintained at 100 psig throughout reaction by adding ethylene as required. The reaction is terminated before the reactant compositions inside the reactor change substantially ( Example 1.
Catalyst Preparation. A stainless steel catalyst addition tube was prepared as outlined above, An aliquot: of 1 milliliter of 10% methylalumoxane (MAO) solution in toluene was added, followed by 5 miliiliters of a toluene solution containing 16 milligrams of (C5Me4SiMe2NC12H23)TiCl2 The scaled tube was
removed from the giovebox and connooted to a reactor port under a containous
flow of nitrogen. A flexible, stiinlcss steel line from the reactor supply manifold was connected to the other end of the addition tube under a continuous flow of nitrogen.
Macromer Synthesis. The reactor was simultaneously purged of nitrogen and pressure tested using two ethylene fill/purge cycles (to 300 psig). Then, the

reactor pressure was raised to -40 psi to maintain positive reactor pressure during setup operations. Jacket water temperature was set to 90°C and 600 milliliters of toluene and 10 milliliters of butene were added to the reactor. The surrcr was set to 750 rpm. Additional cthylene was added to maintain a positive reactor gauge pressure as gas phase ethylene was absorbed into solution. The reactor temperature contt oiler was set to 90°C and the system was allowed to reach steady state. The ethylene pressure regulator was next set to 100 psig and ethylene was addec to the system until a steady state was achieved as measured by zero ethytane uptake. The reactor was isolated and a pulse of toluene pressurized to 300 psig was used to force the catalyst solution from the addition tube into the reactor. The 100 psig ethylene supply manifold was immediately opened to the reactor in order to maintain a constant reactor pressure as ethylene was consumed by reaction.
After 15 minutes of reaction, the reaction solution was quickly heated to 150°C for 30 minutes, then coded to 90°C. A sample of the prepolymerized macromer was removed from the reactor.
LCB Block Copolymer Synthesis. A stainless steel catalyst addition tube was prepared as outlined above. An aliquot of 0.5 milliliter of 10% methylalumcxane (MAO) solution in toluene was added to the tube, followed by 1 milli.iter of a toluene solution containing 0.5 milligrams of (C5Me4SiMe2NC12H23)TiCl2 per milliliter. The scaled tube was removed tram the gloviibox and connected to a reactor port under a continuous flow of nitrogen. A flexible, stainless steel line from the reactor supply manifold was connected to the other end of the addition tube under a continuous flow of nitrogen.
The reactor temperature controller was set to 90°C. Next, 70 milliliters of butene were added to the macromer-containing reactor and the system was allowed to reach thermal equilibrium. Ethylene was next added to the system at

100 p£.ig (total). After allowing the cthylcne to saturate the system (as indicated by zero cthylenc flow), the catalyst was injected in a pulse using high pressure solvent. Reaction progression was monitored by reading ethylene uptake from the electronic mass flow meter. Reaction was terminated by methanol injection after 15 minutes. The product was poured into an excc&s of isopropyl alcohol and evaporated to dryness. Tctal yield of LCB block oopolymer was 42.6 grams,
Example 2.
Catalyst Preparation. A .stainless steel catalyst addition tube was prepared as outlined above. An aliquot of 0.5 milliliter of 10% methylalumoxane (MAO) soluton in toluene was added, followed by S milliliters of a toluene solution containing 8 milligrams of Cp2ZrCl2 The sealed tube was removed from the glove box and connected to a reactor port under a continuous flow of nitrogen. A flexible, stainless steel line from the reactor supply manifold was connected to the other end of the addition tube under a continuous flow of nitrogen.
Macromer Synthesis. The reactor was simultaneously purged of nitrogen and pressure tested using two ethylene fill/purge cycles (to 300 psig). Then, the reactor pressure was raised to -.20 psi to maintain positive reactor pressure during setup operations Jacket water temperature was set to 90°C and 600 miliititers of toluene and 2 milliliters of 80.6 weight percent norboraene in toluene were added to the reactor. The stirrer was set to 750 rpm, Additional ethylene was added to maintain a positive reactor gaujie pressure as gas phase ethylene WAS absorbed into solution. The reactor temperature controller was set to 90oC and the system was allowed to reach steady state. The ethylene pressure regulator was next set to 30 psig and ethylene was added 1:0 the system until a steady state was achieved as measured by zero ethyiene uptake. The reactor was isolated and a pulse of toluene pressurized to 300 psig was used to force the catalyst solution from the addition

tube into the reactor. The 30 psig ethylene supply manifold was immediately opened to the realtor in order to maintain a constant reactor pressure as ethylene was consumed by reaction.
After 15 minutes of reaction, the reaction solution was quickly hefited to 150°C for 30 minutes, then cooled to 90°C. A sample of the prepolymerized macrDmer was removed from the reactor.
LCB Block Copolymer Synthesis. A stainless steel catalyst addition tube was prepared ,is outlined above. An aliquot of 0.5 milL'liter of 10% methylalumoxane (MAO) solution in toluene was added, followed by \ milliliter of a toluene solution containing 1 milligram of (C5ME4SiMe2C12H23)TiCl2 per mill) liter. The sealed rube was removed from the glovebox and connected to a reactor port under a continuous flow of nitrogen. A flexible, stainless steel line from the reactor supply manifold was connected to the other end of the Jiddition tube under a continuous flow of nitrogen.
The reactor temperature controller was s«t to 60°C. Next,60 millliters of 80.()% norbornene in toluene were added and the system was allowed to reach thermal equilibrium. Ethylene was next added to the system at 100 psig (total). After allowing the ethylene to saturate the system (as indicated by zero ethylene flow), the catalyst was injected in a pulse using high pressure solvent. Reaction progression was monitored by reading ethylene uptake from the electronic mass flow meter. Reaction was terminated by melhanol injection after 5 minuses. The prcduct was poured into an excess of isopropyl alcohol and evaporated to dryness. Total yield of LCB block copolymer was 91.9 grams.

Example 3.
Catalyst Preparation. A stainless sttcl catalyst addition tube was prepared as ouilined above. An aliquot vif 1 millilliter of 10% methylalunoxane (MAO) solution in tolune was added, rbilowed by a toluene solution containing 0.25 milligram of (C3Me4SiMe2NC12H23)TiCl2 and 5 micrograms of Cp2ZrCl2. the scale, tube was removed from the giovebox and connected to a reactor port under a continuous How of nitrogen. A flexible, stainless steel line from the reactor supply manifold was connected to die other end of the add it-on tube under a continuous flow of nitrogen.
In tint LCB Block Copolyraer Syn.hesis. The reactor was simultaneously purged ofn.tregen and pressure tested using two ethylene fill/pure cycles (to 3(10 psig) Then, the reactor pressure was raised to -40 psi to maintain positive reactor pressure during setup operations Jacket water temperature was set to 90oC and 600 milliliters of toluene and 20 millitrs butcne were added to the reactor The stirrer was set. to 750 rprr.. Additional ethylene was added to maittain a positive reactor gauge pressure as gas phase ethylene was absorbed into solution. The reactor temperature controller was set to 90oC and the system was allowed to reach steady state. the ethylere pressure regulator was next set to 100 psig and ethylene was added to the system until a steady state was achieved as measured by zero ethylene up take. The reactor was isolated and a pulse of toluene pressurized to 300 psig; -A.,; used to 'ore: the catalyst solution from the addition tube into the reactor. The 100 psig ethylene supply manifold immediately opened to the reactor in order to maintain a constant reactor pressure as ethylene was consumed by reaction Reaction was terminated by methanol injection after7 minutes. The product was poured imc an excess of isopropyl alcohol and evarorated to dryness Total yield of LCB block copolymer was 18.5 grams.
Propeties.
structual data for the select materials are listed in Table in thecase of the first two elas.omeric examples (1 and 2}, the macromer was sampled directly from the reactor and characterized by 'H-NMR and GPC, while for example (mixed metallecne synthesis), the properties o 'the macromer and backbone were attributed from the corresponding single metallocene reactions.
Tensile data were obtained at room temperature and 80'C according to method ASTM 3-14 (in Figure 1, tensile strength at break at room temperature •and 80oC is reported in units of pounds per square inch while elengation as break is reported as a percentage). Recovery was measured at room temperature using sample specimens identical to those used in ASTM D-14 test except the sample was stretched 1:50°/o. tlien released for 10 minutes and the percent recovered to the orginal dimensions measures directly using reference marks en the test sample. Tensile data for select sample indicate the statistically branched LCB block.-copolymer. Formulation exhibited tensile strengthswhich commercially useful limits (see Table 1 and Figure 1). Tensile strength at break is highest for the norbornene LCB block copolymer (4,011psi) whereas the best elastic recovery (89%) was observed in a mixed –metallocene butane LCB block copolymer . both the low molecular weight (10K. Cp2ZrCl2 catalyzed) and high Mn (30-40K) (C5Me2NC12H23)TiCl2-catalyzed) macromer gave LCB block copolymers with useful properties
The ethylene butane LCB block copolymers exhibit elastomeric properties superior to an EXACT 4033 ( Exxon chemical company ) ethylene/butane E/B) rardom copolymer of similar density and equal or better to an ENGAGE 8100 (DOW Chemical Company) ethylene/octane (E/O)random copolymer of similar

Comonomer conectrations can be increased further by decreasing the concentration of ethylene in solution (by decreasing ethylene partial pressure or increasing temperature.)
Table 2Comparision of Branch copolymer Properties Representative LLDPE’S

Propen j- Branch Branch Branch ENGAGE'5 TiXACT*
copo.ymer copolymer c.opolymer 8 IOC 4033
E/B(#1; F/NB (#1) !:/B (#3) n/o K/B
Dens cv (g/m ) 0,887 >0,935 .887 0.8"0 0.880
ASTMD-1505
Com (mol'-i 'HNMR)
Melt: ng Point 119.2 115.:'. 123.5 r W 63
(°C. DSC )
Tensile at B'eak 2401 ^ 4011 3054 io:m 1 1780
psi (kPa), (16.50C) (27,700) (21,000) V.IOO) (12,300)
ASTMD-412
Elongation at 905 I 386 669 950 740
Break (%)
ASTMD-412
Recover-- (%) 76 60 87 76 50
150C'> extension
Note : E - ethylene, B = butene, NB =norbomene. and O = octene.
Table3. Comparsion of Branch Copolymer Properties with commercial styrene
Triblock Copolymer (Fig.1
(Table Removed)

density (Table 2)Comparison of the ethyle:ie/norbornene (E/NB) linear and E/NB l.CH bled; counterparts indicate the LCE block copolymer is somewhat at • defensive in MOST areas, due in part to it much lower norbomene content Of course all of the LCH block copolymcrs neli at much higher temperatures than their linear counterparts due to the crystallizable low molecular weight branch component. It is component It is interesting to note that the LCB block copolymers retain signification tensile strength even when healed above the melt temperature of their amorohous component (see 80°C tensile data). The observed high temperature strength may be due to multi-block-type networks in which amorphous material is anchored to high density', high melting zones by fide chains.
Product characterization The branched olefin copolymer product sample were analyzed by GPC using a Waters 1:50C high temperature system equipped with a DRI Detector, Shodex AT-806V.S column and operating at a system temperature 45oC. The solvent used \vas 1,2,4 trichlorobeii2:er.e, from which polymer sample solutions of 0.1 mg/ml concentration were prepared for injection The total solvent flow rate was 1.0 ml/minute and the injection size was 300 microliters GPC columns v\ere calibrated using a series of narrow polystyrenes '(obtained from Tosoh Corporation, Tokyo, 1989). For quality control a broad-standard calibration ba5ed on the linear PE sample NBS-1475 v/as used. The standard was run with each l(;.-vial carousel. It was injected twice as the first sample of each batch. After elution of the polymer sample, the resulting chromatograms were analyzed using the Waters Expert Ease program to calculate the molecula- weight distribution and Mn Mw and M2 average
Polymer Analyses. The molecular weight , comonomer content, and unsaturated- group structural distributions of the reaction products are reported in Table2. Unsaturated group concentrations (total olefins per1,00carbon atoms) as well as vinyl group selectivities were found to increase with decreasing aluminum metal ratios, all other factors being equal. The reported olefin

WE CLAIM:
1. A process for the preparation of a thermoplastic elastomer composition comprising the steps of:
A] copolymerizing by contacting ethylene, optionally with one or more
copolymerizable monomers selected from the group consisting of C3-C20
alpha olefins, germinally disubstituted monomers, C5-C25 cyclic olefins,
styrenic olefins, C3-C8 alkyl substituted analogs of C5-C25cyclic olefins,
and C3-C8 alkyl substituted analogs of styrenic olefins, with an activated
transition metal metallocene olefin polymerization catalyst of the kind
such as herein described, in a polymerization reaction at a temperature
from 20°C to 200°C to form a copolymer having greater than 40% chain
end-group unsaturation;
B] copolymerizing the product of Step A) with ethylene and one or
more copolymerizable monomers so as to prepare said thermoplastic
elastomer, wherein the thermoplastic elastomer comprises a branched
olefin copolymer comprising:
i] sidechains with number-average molecular weight greater than 10, 000 and less than 45, 000, a Tg as measured by DSC less than or equal to 10°C; and Tm greater than 80°C;
ii] elastomeric backbone polymeric segments having a Tg as

measured by DSC less than or equal to -10°C;
iii] an elongation at break of greater than or equal to 300%;
iv] a Tensile strength of greater than or equal to 1,500 psi (10,300 kPa); and

v] an elastic recovery of greater than or equal to 50%, wherein the mass of the elastomeric backbone segments comprise 40 wt% to 60 wt% of the total polymer mass.
2. The process as claimed in claim 1, wherein said branched olefin
copolymer comprises sidechains derived from ethylene, optionally with
one or more copolymerizable monomers, wherein the Tg of the sidechains
is less than -10°C.
3. The process as claimed in claim 1, wherein said branched olefin
copolymer has sidechains derived from propylene, optionally with one or
more copolymerizable monomers, wherein the Tg of the sidechains is less
than -10°C, and the T m is greater than or equal to 110°C.
4. The process as claimed in claim 1, wherein step A) is conducted by
a solution process having a hydrocarbon solvent, in which said ethylene
and one or more copolymerizabe monomers are contacted with a
transition metal metallocene olefin polymerization catalyst activated by
an alumoxane cocatalyst, and wherein the mole ratio of aluminum to
transition metal is less than 220:1.
5. The process as claimed in claim 4, wherein step B) is conducted in
a separate reaction by solution, slurry or gas phase ethylene
polymerization with an activated transition metal insertion
polymerization catalyst.
6. The process as claimed in claim 1, wherein step A) and B) are
conducted concurrently in the presence of a mixed catalyst system
having one transition metal olefin polymerization catalyst capable of
preparing ethylene copolymers having greater than 40% chain end-group
unsaturation and at least one transition metal olefin polymerization

catalyst capable of incorporating the ethylene copolymers into said branched olefin copolymer.
7. The process substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Documents:

318-del-1998-abstract.pdf

318-del-1998-claims.pdf

318-del-1998-correspondence-others.pdf

318-del-1998-correspondence-po.pdf

318-del-1998-description (complete).pdf

318-del-1998-drawings.pdf

318-del-1998-form-1.pdf

318-del-1998-form-13.pdf

318-del-1998-form-19.pdf

318-del-1998-form-2.pdf

318-del-1998-form-3.pdf

318-del-1998-form-4.pdf

318-del-1998-form-6.pdf

318-del-1998-gpa.pdf

318-del-1998-pct-210.pdf

318-del-1998-pct-220.pdf

318-del-1998-pct-409.pdf

318-del-1998-petition-137.pdf

318-del-1998-petition-138.pdf

318-del-1998-petition-others.pdf

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Patent Number

216545

Indian Patent Application Number

318/DEL/1998

PG Journal Number

13/2008

Publication Date

28-Mar-2008

Grant Date

14-Mar-2008

Date of Filing

09-Feb-1998

Name of Patentee

EXXONMOBIL CHEMICAL PATENTS, INC.,

Applicant Address

5200 BAYWAY DRIVE, BAYTOWN, TEXAS 77520, U.S.A.

Inventors:

#	Inventor's Name	Inventor's Address
1	ERIC J. MARKEL	4534 NATURAL BRIDGE DRIVE, KINGWOOD, TEXAS 77346, U.S.A.
2	ARMEN H. DEKMEZIAN	2806 EVERGREEN CLIFF TR, KINGWOOD, TEXAS 77345, U.S.A.
3	ANDREW JAMES PEACOCK	810 ISLAND MEADOW COURT, HOUSTON, TEXAS 77062, U.S.A.

PCT International Classification Number

C08F 008/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	60/037,323	1997-02-07	U.S.A.
2	60/046,812	1997-05-02	U.S.A.
3	60/067,782	1997-12-10	U.S.A.