CA2129540A1 - Ethylene/branched olefin copolymers - Google Patents

Abstract

High molecular weight copolymers of ethylene and 0.5-10 mole percent branched .alpha.-olefins are disclosed. The polymers have Mw of 30,000-1,000,000, MWD of 2-4, a density of 0.85-0.95 g/cm3, and a high composition distribution breath index. Also disclosed are a method for making the polymers with a cyclopentadienyl metallocene catalyst system, and films, fibers, molded articles and other products made from the copolymers.

Description

W093/21242 PCT/~S93/0~8~
2129Sil~

~TH~LENE/~RANCHE~ OL~ OPO~Y~ERS

Field of the Invention This invention relates to copolymers of ethylene and branched ~-olefins, and more particularly to tough, high strength copolymers thereof. This invention also relates to a process for copolymerizing ethylene with branched ~ olefins utilizing certain transition metal compounds from Group IV B of the Periodic Table of Elements that produces high molecular weight copoly~ers. ~-Backaround of the Inve~tion As far as Applicants are aware, it has not been ~ . :
possible to prepare ethylene copolymers with many ~ -branched ~-olefin comonomers, particularly where the branch is in the 3-position, with sufficiently high molecular weight for most applisations, usin~ a tradi~
tional Ziegler-Natta catalyst.
It has been proposed to use certain metallocenes such as bis(~yclopentadienyl) titanium or zirconium dial~yls in combination with aluminum alkyl~water cocatalyst as a homoge~eous catalyst system for th~
polymerization of olefins in general. Fnr exa~ple:
German Patent Application 2,608~863 teaches the use of a catalyst system for the polymerization of ethylene consisting of bis(cyclopentadienyl) titanium dialkyl, aluminum trialkyl and water; Ger~an Patent Application 2,608,933 teaches an ethylene polymeri~ation catalyst system consi~ting of zirconi~m metallocenes of the general formula (cyclopentadienyl)nZrY4_n, wherein n stands for an integer in the range of 1 to 4, Y for R
CH2AlR2, CH2CH2AlR2 and CH2CH(AlR2)2, wherein R stands for alkyl or metallo alkyl, an aluminum tr~alkyl cocatalyst and water; European Patent Application No.
0035242 teaches a process for preparing ethylene and atactic propylene polymers in the presence of a h~logen-free Ziegler catalyst system of (1) WO93/21242 PCT/US93/0~82 ~ 12 ~ 2-cyclopentadienyl compound of the formula (cyclopentadienyl)nMY4_n in which n is an integer from 1 to 4, M is a transition metal, especially zirconium, and Y i~ either hydrogen, a Cl-Cs alkyl or metallo alkyl group or a radical having the following general formula CH2AlR2, CH2CH2AlR2, and CH~CH(AlR2)2 in which R represents a Cl-Cs alkyl or metallo alkyl group, and (2) an alumoxane; and U. S. Patent 4,564,647 teaches a low pressure process for polymerizing ethylene, either alone or in combination with small amounts of other ~-olefins, in the presence of a catalyst which may comprise a cyclopentadienyl compound, represented by ~ -the formula (Cp)MR2R3R4 wherein (Cp) represents a cyclopentadienyl group, M represents titanium, vanadium, zirconium or hafnium, and R2, R3 and R4 are each an alkyl group having from 1 to 6 carbon atoms, a cyclopentadienyl group, a halogen atom or a hydrogen atom, an alumoxane, which can be prepared by reacting trialkyl aluminum or dialkyl aluminum monohalide with -~
water and a filler. Each of the above patents also teach that the polymerization process employing the homogeneous catalyst system is hydrogen sensitive thereby providing a means to control polymer molecular weight.
As is well known in the prior art, catalyst systems comprising a cyclopen~adienyl compound, hereinafter frequently referred to as a metallocene or metallocene catalyst component, and an alumoxane offer several distinct a~vantages when compared to the more con~entional Ziegler-type catalyst syst~ms. For example, the cyclopentadienyl-transition metal/alumoxane catalyst systems, particularly those wherein the cyclopentadienyl compound contains at least one halogen atom, have demonstrated extremely high activity in the polymerization of ~-olefins, particularly ethylene. Moreover, these catalyst systems produce relatively high yields of polymer WO93/21242 PCT/US93/0~82 ~129~i40 product having a relatively narrow molecular weight distribution. However, these catalyst systemC, when used to prepare copolymers of ethylene with branched ~-olefins in anything more than a very minor proportion, still suffer from the drawbacks of low incorporation rates, and low moleeular weights. ~-For many applications it is of primary importance for a polyolefin to have a high weight average molecular weight while having a relatively narrow ~-molecular weight distribution. A high weight average mole¢ular weight, when accompanied by a narrow molecular weight distribution, provides a polyolefin or an ethylene-lower-~-olefin copolymer with high strength ~ ~-properties. Traditional Ziegler-Natta catalyst systems --a transition metal compound cocatalyzed by an aluminum alkyl -- are in general capabl~ of producing polyolefins having a high molecular weight but with a broad molecular weight distribution.
More recently a catalyst system has been developed wherein the transition metal compound has two or more cyclopentadie.~yl ring ligands, such transition metal ~ ~
compound al80 referred to as a metallocene, which ~ -catalyzes the production of olefin monomers to polyole~ins. Accordingly, ~etallocene com~ounds of the ~5 Group IV B metals, particularly, titanocene and zirconocene have been utilized as the transition metal component in such "metallocene" ~ontaining cataly~t system for the production of polyolef ins and ethylene-~-olefin copolymers. When such metallocenes are cocatalyzed with an aluminum alkyl -- as is the case with a traditional type Ziegler-Natta catalyst system r the catalytic activity of such metallocene catalyst system is generally too low to be of any commercial interest. It has since become known that such metallo¢enes may be cocatalyzed with an alumoxane -rather than an aluminum alkyl -- to provide a metallocene catalyst system of high activity which WO93/21242 PCT/USg3/0~82 2129~ 10 catalyzes the production of polyolefins. The zirconium metallocene species, as cocatalyzed or activated with alumoxane are co monly more active th~n their hafnium or titanium analogues for the general polymerization of -ethylene alone or together with an ~-olefin comonomer.
A wide variety of Group IV B transition metal compounds of the metallocene type have been named as possible candidates for an alu~oxane cocatalyzod catalyst system. Hence, although bis(cyclopentadienyl) 10~ Group IV B transition metal compound~ have been the most preferred and heavily investigated typs metallocenes for use in metallocene/alumoxane catalyst for polyolefin production, suggestions have appeared that mono and tris(cyclopentadienyl) transition metal co~pounds may also be use~ul. See, for example~ U. S.
Patents Nos. 4,522,982; 4,530,914 and 4,701,431. Such mono(cyclopentadienyl) transition metal compounds as have heretofore been suggested as candidates for a metallocene/alumoxane catalyst an~
mono(cyclopentadienyl) transition metal trihalides and trialkyls. ~`
More recently International Publication No. Wo 87/03887 described the use of a composition comprising --a transition metal coordinated to at least one cyclopentadienyl and at least one heteroato~ ligand as a metallocene type component for use in a metallocene/alumoxane catalyst system for ~-olefin polymerization. The composition is broadly defined as a transition metal, preferably of Group IV B of the Periodic Table which is coordinated with at least one cyclopentadienyl ligand and one to three heteroatom ligands, the balance of the coordination requirement being satisfied with cyclopentadienyl or hydrocarbyl ligandc. The metallocene/alumoxane catalyst system described is illustrated solely with reference to transition metal compounds which are WOg3/21242 PCT/US93/0~82 -5- 2 ~ ~ 9 ~ ~ ~

- bis(cyclopentadienyl) Group IV B transition metal ~;
compounds.
Summary of the Invention - ~
In accordance with the pre ent invention, branched ~ ~`
~-olefins ~re copolymerized with ethylene in the presence of a catalyst system comprising an activated cyclopentadienyl transition metal compound. Quite surpri~ingly, it ha~ been found that the branched ~-olefins have a reactivity ratio with ethylene which is ~-su~iciently low to obtain substantial incorporation when the~e catalyst~ are e~ployed, despite the bulky "tail~ of the branched ~-olefin. A~ a result, the -branched ~-olefin i8 unexpectedly incorporated into the copolymer at a competitive rate with the ethylene, and the compo~ition distribution is substantially uniform and generally rando~.
The present invention resides, at least in part, in the discovery that branched ~-olefin~ can be -polymerized with ethylene u~ing certain monocyclopentadienyl metallocene catalysts to obtain a high ~olecular weight copolymer with a high pxoportion of branched a-olefin incorporation, a narrow molecular weight distribution branched ~-olefin comonomer distribution. The present invention also resides, in part, in the discovery that certain of these novel copolymers have very surprising properties, such as, for example, modulus, strain to break, rheological properties, storage and 1088 moduli, dissipative characteristics, and the like. In particular the -~
preferred copolymers of the present invention exhibit surprising toughness, have suppressed or nonexistent secondary phase transitions in the temperature ranges convention~l for ethylene/linear ~-olefin copolymers, -and have a secondary phase transition temperature and/or magnitude different from such conventional copolymers.

WOg3/21242 PCT/US93/0~82 21295~ ~ ~
In one aspect, then, the present invention provides a copolymer of ethylene and preferably from about 0.5 to about 10 mole pereent, more preferably from about 1 to about 8, and e~pecially from about 1 to about 5 mole percent, of a branch~d ~-olefin incorporated sub~tantially randomly in the copolymer.
The copolymer is generally semicrystalline and has a density of from about 0.85 to about 0.95 g/cm3. The copolymer preferably has a weight average molecular weight from about 30,000 to about 1,000,000 daltons or more, more pr ferably from about 80,000 to about 500,000 daltons, and a molecular weight distribution substantially between of about 4 or less preferably between about 2 and about 4. The copolymer has a generally unifor~ comonomer composition distribution.
The present invention also provide~ useful articles made from the foregoing copolymers, including fibers, filr~, sheet~, coatings and molded article~. In particular, the invention provides fibers, films and other forms of the copolymer wherein the copolymer is axially oriented by phy~ical or mechanical proce~ing ~uch as, for example, drawing, extrusion, and the like.
In a further aspect, the present invention provides a method of preparing a copolymer by contacting ethylene and the branched ~-olefin comonomer with a catalyst at polymerization conditions wherein the ethylene:comonomer reactivity ratio iæ less than about 75. In a preferred embodiment, the foregoing copolymers are prepared by contacting ethylene and a branched ~-olefin with a catalyst system comprising a Group IV B transition metal component and an activating coJponent for the catalyst at polymerization conditions, and recovering a high molecular weight, narrow molecular weight distribution copolymer having a generally uniform, random ~-olefin composition distribution. The "Group IV B transition metal WO93/21242 PCT/US93/0~82 _7_ 2 1 2g ~ ~(3 component" of the catalyst system is represented by the general formula: (CsHs_y-x~x) ~' \ ,Q `
.y /M~
/ Q
(JR' z-l-y) wherein: M is Zr, Hf or Ti and is in its highest formal oxidation state (+4, d complex);
(C5H5_y_XRx) is a cyclop~ntadienyl ring which is :~
substituted with from zero to fi~e substituent groups R, "x" is 0, l, 2, 3, 4 or 5 denoting the degree of ~::
substitution, and each substituent group R is, independently, a radical selected from a group 15 consisting of Cl-C20 hydrocarbyl radicals, sub~tituted ~.
Cl-C20 hydrocarbyl radicals wherein one or more hydrogen atoms is replaced by a halogen radical, an amido radical, a phosphido radical, an alkoxy radical, an alkylborido rad~cal? or any o~her radical containing ;~
20 a Lewis acidic or basic functionality, Cl-C2~ -hydrocarbyl-substituted metalloid rad~cals wherein th~
metalloid i~ selected from the Group IV A o~ the Periodic Table of Elements, and halogen radicals, amido radicals, phosphido radicals, alkoxy radical~, alkylborido radicals or any other radical containing Lewis acidic or basic functionality or (CsHs_y_xRx) is a cyclopentadienyl ring in which two adjacent R-groups are joined forming a C4-C20 ring to give a saturated or unsaturated polycyclic cyclopentadienyl ligand æuch as 3G indenyl, tetrahydroindenyl, fluorenyl or octahydrofluorenyl;
(JR~z_l_y) is a heteroatom ligand in which ~ is an element with a coordination number of three from Group V A or an element with a coordination number of two -`;
from Group VI A of the Periodic Table of Elements, preferably nitrogen, phosphorus, oxygen or sulfur, and each R' is, independently a radical selected from the WO93/21242 ~ PCT/US93/0~82 ~ 1 2 ~ 0 : ;

group consisting of Cl-C20 hydrocarbyl radicals, substituted Cl-C20 hydrocarbyl radicals wherein one or more hydrogen atoms is replaced by a halogen radical, an amido radical, a phosphido radical, an alkoxy rad~cal, an alkylborido rad~cal or any other radical containing a Lewis acidic or basic functionality and "z" is the coordination number of the element J;
Each Q may be independently any univalent anionic ligand such as halogen, hydride, or substituted or unsubstituted Cl-C20 hydrocarbyl, alkoxide, aryloxide, amide, arylamide, phosphide or arylphosphide, provided :~
that where any Q is a hydrocarbyl such Q ls different from (Cs~s_y_xRx) or both Q together may be an alkylidene or a cyclometallated hydrocarbyl or any other divalent anionic chelating ligand;
"y" is 0 or 1 when w is greater than 0; y is 1 when w is 0; when -y" is 1, T is a covalent bridging group containing a Group IV A or V A element such as, but not limited to, a dialkyl, alkylaryl or diaryl 20 silicon or germanium radical, alkyl or aryl phosphine ~ :
or amine radical, or a hydrocarbyl radical such as methylene, ethylene and the like;
L is a Lewis base such a~ diethylether, tetraethylammonium chloride, tetrahydrofuran, dimethylaniline, aniline, trimethylphosphine, n-butylamine, and the like; and "w" is a number from 0 to 3; L can also be a ~econd transition metal compound of the same type such that the two metal centers M and M' are bridged by Q and Q', wherein M' has the same meaning as M and Q' has the same meaning as Q. Such compounds are represented by the formula:

(Cs s_y_~ x) Q, (/ ~z 1 Y

~Y~ / Q ~-Q~ (~5H5 y xRx) (JR~z_~_y~

WO g3/21242 , Pcr/uss3/o34s2 ;~
~:'` ;`
-9- 2129~4~ :`

.~ . .; .i. ~.
The activating component for the metallocene` `
catalyst co~ponent can be an alumoxane component repre8~nt~d by th~ for~ulas: (R3-Al-0)~: R4(R5-Al-O)m~
AlR62 or mixture~ thereof, wherein R3-R6 are, independently, a univalent anionic ligand such a~ a Cl-C5 alkyl group or halide and "m~ is an integer ranging from l to about 50 and preferably is from about 13 to about 25. Alternatively, the activating component for the ~etallocene cataly~t co~ponent can compriQe a c~tion capable of irrever~ibly reacting with a ~ub~tituent of the -tallocene component and a bulky, non-coordinating anion capable of stabilizing the metal cation formed ~y the reaction between the irreversibly-reacting cation and the metallocene component - --substituent.

Brief De~criDtion of the Drawinas Fig. 1 i~ a plot comparing initial modulus (Y) ver~us co~ono~er content for th~ ethylene/3,5,5- -~
trimethyl-hexene-l copolymer of Example 3 and several ethylene/l~near-~-olefin (C4-C18) copolymers having molecular weights between 80,000 and 125,000.
Fig. 2 is a plot o f tan d (l Hz, 10% toræion strain) versus temperature for the ethylene/3,5,5-trimethylhexane copolymer of Example 3.
Detailed Descri~tion_of the In~ention The present invention relates to copoly~ers ofethylene with branched -olefins~ The branched ~-olefin comonomer is generally not copolymerizable at a competitive rate with ethylene when conventional Ziegler-Natta catalysts are used. The branched ~-olefin generally has at least one alkyl branch adjacent to the ethylenic unsaturation of the comonomer, and thus, when copolymerized with ethylene, forms a 35 copoly~er having a backbone or main chain and pendant ~
side chains randomly interspersed along the backbone, ~ -with alkyl branches on the side chain adjacent the .

WO93/21242 PCT/US93/0~82 21295~
0-- .

backbone. The alkyl branches on the side chains are prefer~bly closer to the polymer backbone th~n the terminal carbon in the side chain, or ~t~ted another way, the alkyl branch on the comonomer is preferably closer to the ethylenic unsaturation than the terminal carbon of the longest straight chain of the comonomer.
The comonomer contains at least two alkyl branche~, and more preferably ha~ from 2 to 4 alkyl branches along the longest straight chain. Preferred branches have from 1 to 3 carbon atoms each, such as methyl, ethyl, propyl and i~opropyl. The branched ~-ole~in comonomer must have at least 5 carbon atoms, more preferably has at least 6 carbon ato~s, and most preferably has at least 8 carbon atoms. The branched comonomer i5 not, in general, re~tricted at any particular upper li~it of size and C100 or larger could be used, although as a practical matter, the branched comonomer preferably contains les~ than about 30 carbon atoms, more preferably up to about 14, and especially up to ab~ut 2Q 12 carbon atoms.
The br~nched -olefin preferably has up to about 30 carbon atom~, preferably 6 to 14 carbon atoms and more preferably 8 to 12 carbon atoms.
Specific representative examples of suitable branched ~-olefins include 3,4-dimethylpentene-1, 4-methyl-3-ethylpentene-1, 3,4,4-trimethylpentene-1, 4,4-dimethyl-3-ethylpentene-1, 3,4-dimethylhexene~
3,5-dimethylhexene-1, 4-methyl-3-ethylhexene-1, 5-methyl-3-ethylhexene-1, 3-methyl-4-ethylhexene-1, 4- ~;
methyl-3-propylhexene-1, 5-methyl-3-propylhexene-1, 3,4-diethylhexene-1, 4-methyl-3-isopropylhexene-1, 5-methyl-3-isopropylhexene-1, 3,4,4-trimethylhexene-1, 3,4,5-trimethylhexene-1, 3,5,5-trim¢thylhexene-1, 4,4-dimethyl-3-ethylhéxene-1, 4~s-dimethyl-3-ethylhexene 5,5-dimethyl-3-ethylhexene-1, 3,4-dimethyl-4-ethylhexene-1, 3,5-dimethyl-4-ethylhexene-1, 4-methyl-3,4-diethylhexene-1, 5-methyl-3,4-diethylhexene-1, 3-W093/21242 . PCT/US93/0~82 2 1 2 ~ l U

methyl-4,4-diethylhexene-1, 3,4,4-triethylhexene-1, 4,4-dimethyl-3-propylhexene-1, 4,5-dimethyl-3-propylhexene-l, 5,5-dimethyl-3-propylhexene-1, 4,4-dimethyl-3-isopropylhexene-1, 4,5-dimethyl-3-isopropylhexene-l, 5,5-dimethyl-3-isopropylhexene-1, 3,4,4,5-tetramethylhexene-1, 3,4,5,5-tetramethylhexene~
1, 4,4,5-trimethyl-3-ethylhexene-1, 4,5,5-trimethyl-3- ::-ethylhexene-l, 3,4,5-trimethyl-4-ethylhexene-1, 3,5,5- :
trimethyl-4-ethylhexene-1, 4,5-dimethyl-3,4-diethylhexene-l, 5,5-dimethyl-3,4-diethylhexene-1, 3,5-d~methyl-4,4-diethylhexene-1, 5-methyl-3,4,4- ---:
triethylhexene-l and the like.
The copolymer can further contain additional monomers, usually in relatively minor amounts, which do not substantially adversely affect the novel properties of the copolymers. Such termonomers include vinyl and vinylidene compounds, for example, generally linear ~- -aolefins having from 3 to 100 carbon atoms, preferably -~
from 3 to 20 carbon atoms, and particularly from 3 to 20 10 carbon atoms, such as propylene, l-butene, -~
isobutene, l-pentena, 4-methylpentene~ hexene, 1~
heptene, loctene, 1-nonene, and the like; diene~, such as 1,3butadiene, 2-methyl-1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene and the like; ~inyl aromatic and alicyclic monomers, such as styrene, alkyl-substituted styrene, cyclopentene, vinyl cyclohexane, ~:
vinyl cyclohexene phenyl butadiene, vinyl norbornene, and the like; and co~binations thereof. Specifically conte~plated are terpolymers vf ethylene, the branched ~-olefin and from about 2 to about 25 mole percent, preferably 2 to 10 mole percent, of a linear C3 to C
~-olefin. :
Preferably, the ethylene is interpolymerized with from about 0.5 to about 10 mole percent of the branched `~
3S ~-olefin, more preferably from about 1 to about 8 ~ole percent branched ~-olefin, and especially from about 1 to about 5 mole percent branched ~-olefin. In general, WO93/21242 ~ PCT/US93/0~82 212~5~0 -12-at an increased branched ~-olefin content, the properties imparted by the branched ~-olefin are more pronounced, e.g., toughness and strain hardening increase.
The polymers of the present invention are generally semicrystalline, but can be amorphous if ~ore than about 12 mole percent of a linear C3-C8 ~-olefin termonomer is incorporated. The ethylene/branched ~-olefin copolymers generally have a density from about 0.85 to about 0.95 g/cm3.
The polymers of the present invention have a surprisingly high molecular weight, preferably from about 30,000 to about 1,000,000 daltons or more, depending on the desired end-use application. As used herein, molecular weight refers to the weight average molecular weight (Nw), unless otherwise indicated. The unique characteristics of the ethylene/br~nched ~
olefin copolymers are not generally observed at lower molecular weights where there is limited chain entanglement. Polymers having a molecular weight higher than this range, while theoretically possible, are di~ficult to prepare a~ a practical matter. ~ost commercially useful polymers, e.g. in film, fiber and molding appli ations, haYe Mw in the range of from about 80,000 to about 500,000 daltone.
The copolymers of the present invention havs a narrow molecular weight distribution gMWD). Thi~
surprising fact is reflected in a low polydispersity, i.e. a ratio of Mw to number average molecular weight (Mn)~ The MWD (MW/Mn) is ~enerally in the range of from about 2 to about 4, even in the copolymeræ of very high molecular weight.
The copolymers of the present invention are substantially random and quite surprisingly should have a fairly uniform branched ~-olefin distribution throughout the copolymer. This uniform composition can be reflected in a relatively high composition WO93/21242 PCT/US93/0~2 212~ 10 ~`

distribution breadth index (CD8I). As used herein, `
CDBI i8 defined as the percentage by weight of the copolymer molecules having a branched ~-olefin comonomer content within 50 percent of the median molar 5 comonomer content, i.e. +50 percent of the median Clo- ~-C10O olefin content. Homopolymers ~uch as polyethylene, which do not contain a comonomer, thus have a CDBI of 100%. The CDBI of a copolymer is readily calculated from data obtained by techniques 10 known in the art, such as, for example, temperature ~ -rising elution fractionation (TREF) as described in U~
S. Ser. No. 151,350 or Wild et al., J. Poly. Sci. Poly.
Phvs. Ed., vol. 20, p. 441 (1982). The ethylene/branched ~-olefin copolymers herein generally should preferably have a CDBI on the order of about 50 ,~ .
percent or more, i.e. about 50 percent or more of the copolymer having a molar branched ~-olefin comonomer content within +50 percent of the median comonomer content. In contrast, linear low dens~ty polyethylene prepared using conventional Ziegler-Natta catalyst has a CDBI on the order of 30 to 40 percent. -The pre~ent polym~rs compri~e linear, comb-like ~ --molecules, wherein each of the side chains are of short, controlled branching which reflects the configuration of the branched ~-olefin comonomer, as opposed to uncontrolled long chain branched polymers ~-which are generally obtained by free-radically initiated, high pressure ethylene polymerization -~
conventionally used to obtain low density polyethylene (LDPE). This derives from the use of a single-site coordination catalyst as opposed to a free radical catalyst. The olefin polymerizes in a predominantly head-to-tail fashion so that the polymer molecule has a -~
generally linear main chain formed by polymerization at the carbon-carbon double bond, and a plurality of side chains of controlled length and branching correspondinq to the aliphatic "tails" of the branched ~-olefin.

WO93/21242 ~ PCT/~S93/0~82 2129~A0 -14-The branched side chains in the present copolymers can have a profound effect on the crystalline behavior of the copolymers. For example, linear low density polyethylenes invariably have secondary phase transitions at from about -120-C to about -90-C
(generally known as T~ ) and at from about -30^C to about 20-C (generally known as T~). In semicrystalline L~nPE, these T~ and Ty phenomena appear to be relatively unaf~ected, or only sl~ghtly lO affected, by the size of the C3-Cg linear ~-olefin ;-comonomer, as well as co~onomer content. However, in ;~
the case of the pre~ent copolymers where the side chains are branched adjacent the generally linear polymer the T~ and T~ are at least highly `
15 suppresaed, and usually entirely eliminated, at the ~- -conventional LLDPE temperatures at which they are normally observed. Instead, a secondary phase transition temperature (which could be an altered or shifted T~ and/or T~ owing to the branching of the side chains) appears outside the conventional ranges.
For example, in a copolymer containing a 3-~ethyl branched ~-olefin such as 3,5,5-~rimethylhexene-l, the T~ disappears c~mpletely, ths copolymer is essentially free of a~y phase transition at -30~C to 20-C, and a secondary phase transition temperature is seen at about 70-80-C. This copolymer is also observed to exhibit very high toughness and profound strain hardening. As the position of the branch is moved away frcm the backbone, say to the 5-position aS in, for example, 5-ethylnonene copolymers, the T~ can be observ¢d somewhat, although significantly suppressed, T~ is still not apparent in the -30-C to 20-C range, and a secondary phase transition is observed at about -35-C to about 40-C. Also, the toughness is decreased 35 and strain hardening much less pronounced than with the -3,5,5-trimethylhexene-l copolymers.

WO93/21242 PCT/US93/0~8~

-15- 2 1 2 9 ~

The novel characteristics of the ethylene/branched ~-olefin copolymers of the present invention, i.e~
simultaneously high branched ~-olefin ccntent, high MWt narrow MWD and a relatively good degree of random comonomer incorporation, impart a nu~ber of unique and, in some cases, rather surprising physical, rheological and other properties to the copolymers. As a conseguence, the copolymers have a wide number of uses, particularly where high toughness is desirable.
For structural film applications, the generally ;
semicrystalline copolymers preferably have a density from about 0.88 to about 0.93 g/cm3. The present films ~ -have high strength and a high Young's modulus, but have exceptionally high toughness (generally taken as the integrated area under the stress-strain curve) at increasing strain or elongation, and excellent ;-~
processability due to rheologic~l properties.
The copolymer can be used in a monolayer film, e.g., a film comprised of a single layer of the copolymer without adjacent layers made of a different polymer. Alternatively, the copnlymer can be used as one or more layer~ in a multi-layer film, e.g. a~ a structural and/or skin layer.
The film can include one or more conv~ntional additives, e~g. antiblock (slip and/or antiblock) additives which may be added during the production of the copolymer or subs~quently blended in. Such additives are well-known in the art and in~lude, for example, silicas, silicates, diatomaceous earths, talcs and various lubricants. These additives are preferably utilized in amounts ranging from about 100 ppm to abou~
20,000 ppm, more preferably be~ween about 500 ppm to about 10,000 ppm by weight based upon the weight of the ~
copolymer. The copolymer can, if desired, also include `
one or more other well-known additives such as, for example, tackifiers, oils, viscosiry modifiers, waxes, antioxidants~ ultraviolet absorbers, antistatic agents, WO93/21242 PCT/US93/O~X2 ~ l29~ 10 -16-release agents, pigments, colorants, crosslinking agents, coupling agents, fillers, or the like; however, this again should not be con~ider~d a limitation of the present invention.
The film is produced from the ethylene copolymer by any one of a number of well-known extrusion or coextrusion techniques. As preferred examples, any of the blown or chill roll cast proce~ses known in the art, with or without axial or biaxial orientation obtained by mechanically working the film, as by stretching, drawing, extrusion or the like, can be used.
As previously mentioned, the semicrystalline films of the present invention have properties making them especially well suited for use in a variety of applications. For example, these films can be used in stretch/cling films or made into other forms, such as a --tape, by any one of a number of well-known cutting, slitting and/or rewinding operations. Physical ~ -properties including, bu~ not limited to, tensile strength, tear strength and elongation can be ad~usted over wide ranges by alterin~ the copolymer properties and specifications, as well as additive pac~ages, as appropriate to meet the requirements to a gi~en structural, wrapping, bundling, tapin~ or other application.
The copolymer of the present invention can also be blended with another polymer such as LLnPE, LDPE, HDP~, polypropylene or the like to improve the properties of the blend polymer. The copolymer of the present i~vention can, for example, be blended with another polymer to enhance the toughness of the blend polymer.
The improvement in toughness generally depends on the toughness of the ethylene/branched ~-olefin copoly~er and the relative properties of the blend polymer, and can be balanced against the other properties of the blend.

WO93/21242 PCT/US93/0~82 --17 2 1 2 ~ r~

The copolymer of the present invention is also contemplated to be used in fibers, particularly to make high tenacity fibers. It is contemplated that the copolymer can be formed into fiber using conventional fiber formation equipment, such a~, for example, eguipment commonly employed for melt spinning or to form melt blown fiber, or the like. In melt spinning, either monofilaments or fine denier fibers, a relatively high melt strength i~ generally required, and the copolymer preferably has a melt index (MI) of from about lO to about lO0 dg/min. (As used herein, MI ; ~;
is determined in accordance with ASTM D-1238, condition E (l90-C/2.16 kg)). Typical melt spinning equipment includes a mixing extruder which feeds a spinning pump which ~upplies polymer to mechanical filters and a spinnerette with a plurality of extru~ion holes ;~
therein. The filament or filaments formed from the ;-spinnerette are taken up on a take up roll after the ~ ;
polyolefin has solidified to form fiber~. If desired, ~;
the fiber may be subjected to further drawing or stretching, either heated or cold, and also to texturizing, such as, for example, air jet texturing, steam jet texturing, stuffing box treat~ent, cutting or crimping into staples, and the like.
In the case of melt blown fiber, the copolymer is generally fed to an extrusion die along with a high pre~sure ~ource of air or other inert gas in such a fashion as to cause the melt to fragment at the die orifice and to be drawn by the pa~sage of the air into short fiber which solidifies before it i~ deposited and taken up as a mat or web on a screen or roll which may be o~tionally heated. Melt blown fiber formation generally requires low melt viscosity material, and for this reason, it is desirable to use a copolymer in melt blown fiber formation which has a MI in the range from about 400 to about lO00 dg/min.

WO93/21242 . PCT/US93/0~82 .

~ 1 2 9 r~ l1 p In a preferred embodiment, the copolymer of the present invention can be used to form nonwoven fabric. :~
The fiber can be bonded using conventional techniques, such as, for example, needle punch, adhesive binder, 5 binder fiber~, hot embossed roll calendaring and the ;:
like.
It is al~o contemplated that the copolymer of the pre~ent invention can be used as one component of a biconstituent or bicomponent fiber wherein the fiber includes a second component in a side-by-side or sheath-core configuration. For example, the copolymer and LLDPE, LDPE, HDPE, polypropylene, polyethylene terephthalate (PET) or the like can be formed into a side-by-side or sheath-core bicomponent fiber by using :~
eguipment and techniques known for formation of bicomponent fibers. Alternatively, the copolymer of the pre~ent invention can be used as the dispersed or matrix phase in a biconstituent fiber.
The ~opolymer of the present invention has a wide number of uses because of it~ unique propertie~ which can b~ varied to suit particular application~. The copolymer can have utilityf for example, in film, fiber and molding applications, as previously mentioned; ln ..
applications requiring -euper tough polymers with the unique morphology of the present copolymer; in film ~urface modifications wherein the copolymer is added to or coated on, e.g. a conventional polyethylene, and th~
film surface can al50 be subjected to corona discharge or other surface treatment; in polymer processing as an additive to enhance the melt viscosity of the thermoplastic, elastomer or thermoplastic elastomer being processed; in elastcmer applications, particularly vulcanizable elastomers wherein the copolymer includes a termonomer which imparts vulcanizability; in applications requiring a tough polymer; in laminates and coating applications as a hydrophobic, corrosion-resistant coating; in curable WO93/21242 PCT/US93/0~82 2129~0 coatings, where the copolymer includes a termonomer which imparts vulcanizability through residual unsaturation (e.g. a diene termonomer), which are crosslinkable by the action of an acrylate crosslinking agent (e.g. 2-ethyl-2-hydroxymethyl-1,3-propanediol trimethacrylate), a silane coupling aqent, irradiation (e.g. electron beam or gamma rays), or the like; in variou~ molding applications, e.g. injection molding, rotational molding, blow molding and thermoforming; and ;
the like.

CATALYST COMPONENT
The present invention relates to copolymers of ethylene and branched a-olefins made by a process comprising polymerizing branched ~-olefins with ethylene in the presence of a catalyst providing a low ~ -ethylene:co nomer reactivity r?tio, preferably a ratio le~ than about 75, more preferably less than about 50, and especially from about 25 to about 50. A preferred 20 càtalyst comprises an activated cyclopentadienyl- -transition metal compound wherein the transition metal component is from Group IV B.
The Group IV B transition metal compon~nt of the catalyst system is repres@nted by the general formula:

(Cs~s-y-xRx) ,' \ ~Q
~y / M~ ~ ~~~
(JR~z_l_y) wherein: M is Zr, Hf or Ti and is in its highest formal oxidation state (+4, d complex);
(CsHs_y_xRx) is a cyclopentadienyl ring which is substituted with from zero to five substituent groups R, ~x" is 0, 1, 2, 3, 4 or 5 denoting the degree of WO93/21242 1 PCT/US93/0~82 2 12~ 20-,,,",.,;.
substitution, and each substituent group R is, independently, a radical selected from a group consisting of Cl-C20 hydrocarbyl radicals, substituted C1-C20 hydrocarbyl radi~als wherein one or more ~-S hydrogen atoms is replaced by a halogen radical, an amido radical, a phosphido radical, an alkoxy radical or any other radical containing a Lewis acidic or basic functionality, Cl-C20 hydrocarbyl-substituted metal~oid radicals wherein the metalloid is selected from the Group IV A of the Periodic Table of Elements, and halogen radicals, amido radicals, phosphido radicals, alkoxy radicals, alkylborido radicàls or any other radical containing a Lewis acidic or basic functionality or (CsHs_y_xRx) is a cyclopentadienyl ring in which two adjacent R-groups are joined forming C4-C20 ring to give a saturated or unsaturated polycyclic cyclopentadienyl ligand such as indenyl, tetrahydroindenyl, fluorenyl or octahydrofluorenyl;
(JR'z-l-y) is a heteroatom ligand in which J is an element with a coordination number of threa from Group V A or an element with a coordination number of two from Group VI A of the Periodic Table of Elements, preferably nitrogen, phosphorus, oxygen or sulfur with nitrogen being preferred, and each R~ is, independently a radical selected from a group consisting of Cl-C20 hydrocarbyl radicals, substituted Cl-C20 hydrocarbyl radiGals wherein one or more hydrogen atom is replaced by a halogen radical, an amido radical, a phosphido radical, an alkoxy radical or any other radical containing a Lewis acidic or basic functionality, and "z" is the coordination number of the element J;
Each Q is, independently any univalent anionic ligand such as halogen, hydride, or substituted or unsubstituted Cl-C20 hydrocarbyl, alkoxide, aryloxide, ~ :
amide, arylamide, phosphide or arylphosphide, provided that where any Q is a hydrocarbyl such Q is different from (CsHs_y_xRx) or both Q together may be an WO93/21242 . PCT/US93/0~82 2 1 2 9 ~ ll f~ ~

alkylidene or a cyclometallated hydrocarbyl or any ; :~
other divalent anionic chelating ligand. ;~
"y" is 0 or 1 when w is greater than 0; y is 1 ~ :
when w is 0; when -y" is 1, T is a covalent bridging ~
5 group containing a Group IV A or V A element such as, ::
but not limited to, a dialkyl, alkylaryl or diaryl . -silicon or germanium radical, alkyl or aryl phosphine or amine radical, or a hydrocarbyl radical such as methylene, ethylene and the like. ~-L is a Lewis base such as diethylether, ::
tetraethylammonium chloride, tetrahydrofuran, :;
dimethylaniline, aniline, trimethylphosphine, n~
butylamine, and the like; and "w" is a number from 0 to 3; L can also be a second transition metal compound of the samé type such that the two metal centers M and M' are bridged by Q and Q', wherein ~' has the same meaning as M and Q' has the same meaning as Q. Such co~pounds are represented by the formula~

,S\y xRY Q, (~ Z-l-y) ~ `
Ty M~ ,-M; ~Ty ~ / Q -'Q~' (C5~5_y-xRx~

A preferred activator is an al~moxane component which may be represented by the formulas: (R3 Al-O)m;
R4~R5-Al-O)m-AlR62 or mixtures thereof, wherein R3-R6 ~re, independently, a univalent anionic ligand such as a C1-Cs alkyl group or halide and "m" is an integer ranging rom 1 to about 50 and preferably is from about 13 ~o about 25.
Examples of the T group which are suitable as a constituent group of the Group IV B transition metal component of the catalyst system are identif-ed in Column 1 of Table 1 under the heading "Tn.

WO 93/21242 PCr/US93/03482 2129~4~ -22- `
TABLE 1 ~
.~

SUBSTlT-lTE SHEET

WO 93/21242 2 1 2 9 5 ~ ~cr/US93/03482 TA:E3LE 1 ( CONT ' D ) ~ ~:

_ C ~ ~ _ ~ .. _ _ SlJBSTITUTE SHEET

WO93/21242 PCT/US93/0~82 2 1 29 S~ 24-Exemplary hydrocarbyl radicals for the Q are methyl, ethyl, propyl, butyl, amyl, isoamyl, hexyl, isobutyl, heptyl, octyl, nonyl, decyl, cetyl, 2-ethylhexyl, phenyl and the like, with methyl being preferred. Exemplary halogen atoms for Q include chlorine, bromine, fluorine, and iodine, with chlorine being preferred. Exemplary alkoxides and aryloxides for Q are methoxide, phenoxide and substituted phenoxides such as 4-methylphenoxide. Exemplary amides for Q are dimethylamide, diethylamide, methylethylamide, di-t-butylamide, diiospropylamide and the like. Exemplary amides for Q are dimethylamide, diethylamide, methylethylamide, di-t-butylamide, diisopropylamide and the like. Exemplary aryl amides are diphenylamide and any other substituted phenyl amides. Exemplary phosphides for Q are diphenylphosphide, dicyclohexylphosphide, diethylphosphide, dimethylphosphide and the like.
Exemplary alkyldiene radicals for both Q together are methylidene, ethylidene and propylidene. Examples of the Q group which are suitable as a constituent group or element of the Group IV B transition metal component of the catalyst system are identified in Column 4 of Table 1 under the heading "Q".
Suitable hydrocarbyl and substituted hydrocarbyl radicals, which may be substituted as an R yroup for at least one hydrogen atom in the cyclopentadienyl ring, will contain from l to about 20 carbon atoms and include straight and branched alkyl radical~, cyclic hydrocarbon radicals, alkyl-substi~uted cyclic hydrocarbon radicals, aromatic radicals, alkyl-substituted aromatic radicals, phosphido substituted ~`
hydrocarbon radicals, alkoxy substituted hydrocarbon radicals, alkylborido substituted radicals and ;~
35 cyclopentadienyl rings containing one or more fused -`
saturated or unsaturated rings. Suitable organometallic radicals, which may be substituted as an ~-WO93/21'42 . PCTJUS93/0~82 2129~ 1~

- R group for at least one hydrogen atom in the ~
eyelopentadienyl ring inelude trimethylsilyl, : ;
triethylsilyl, ethyldimethylsilyl, methyldiethylsilyl, triph~nylgermyl, tr-imethylgermyl and the like. Other suitable radieals that may be substituted for one or more ~ydrogen atom in the eyelopentadienyl ring inelude `
halogen radieals, amido radieals, phosphido radieals, alkoxy radieals, alkylb-~rido radieals and the like.
Examples of eyelopentadienyl ring groups (CsH5_y_xRx) whieh are suitable as a eonstituent group of the Group rv B tr~nsition metal eomponent of the eatalyst system are identified in Column 2 of Table 1 under the heading (C5H5_y--XRX) -Suitable hydroearbyl and substituted hydrocarbyl radieals, whieh may be used as an R' group in the heteroatom J lig~nd group, will eontain from 1 to about 20 earbon atoms and inelude straight and branehed alkyl radieals, eyelie hydroearbon radieals, alkyl- ~;
substituted eyelie hydroearbon radieals, aro~atie 20 radieals, alkyl-substituted aromatie radieals, halogen :~
radieals, amido radieals, phosphido radieals, alkylborido radieals and the like. Examples of heteroatom ligand group-~ (JR' 2-1-y) whieh are suitable as a eonstituent group of the Group IV B transition metal component of the catalyst system are identified in Column 3 of Table 1 under the heading (JR'z-l-y). ~ ~:
Table 1 depiets representative eonstituent ;~
moieties for the "Group IV B transition metal eomponent", the list is for illustrative purposes only and should not be eonstrued to be limiting in any way~
A number of final eomponents m;~y be formed by permuting all possible combinations of the eonstituent moieties with eaeh other. Illustrative eompounds are:
dimethylsilyltetramethyl-cyelopentadienyl-tert-butylamido zireoni~m dichloride,dimethylsilytetramethylcyclopentadienyl-tert-butylamido hafnium diehloride, dimethylsilyl-tert-butyl-WO93/21242 PCT/US93/0~82 2 12 9~110 -26-cyclopentadienyl-tert-butylamido hafnium dichloride, dimethylsilyltrimethylsilylcyclopentadienyl-tert-butylamido zirconium dichloride, dimethylsilyl-tetramethylcyclopentadienylphenylamido zirconium dichloride, dimethylsilyltetramethylcyclopentadienyl-phenylamido hafnium dichloride, methylphenylsilyl-tetramethylcyclopentadienyl-tert-butylamido zirconium dichloride, methylphenylsilyltetramethylcyclopentadienyl-tert-butylamido hafnium dichloride, methylphenylsilyl-tetraDtethylcyclopentadienyl-tert-butylamido hafniu~n dimethyl, dimethylsilyltetramethylcyclopentadienyl-p-n-butylphenylamido zirconium dichloride, dimethylsilyl-tetramethylcyclopentadienyl-p-n-butylphenylamido hafnium dichloride.
As noted, titanium species of the Group IV B
transition metal compound have-generally been found to yield catalyst systems which in comparison to their zirconium o- hafnium analogues, are of higher activity ~ ;
20 and ~-olefin comonomer incorporating ability. -~
Illustrative, but not limiting of the titaniu~ species which exhibit such superior properties are methylphenylsilyltetramethylcyc:lopentadisnyl-tert~
butylamido titanium dichloride, dimethylsilyl-tetramethylcyclopentadienyl-p-n-butylphenylamido titanium dichloride, dimethylsilyltetramethylcyclopentadienyl-p-methoxyphenylamido titanium dichloride, dimethylsilyl-tert-butylcyclopentadien~l-2,5-di-tert-butylphenylamido titanium dichloride, dimethylsilylindenyl-tert-butylamido titanium dichloride, dimethylsilyltetramethyl-cyclopentadienylcyclohexylamido titanium dichloride, dimethylsilylfluorenylcyclohexylamido titanium .~ . .
dichloride, dimethylsilyltetramethylcyclopentadienyl-phenylamido titanium dichloride, dimethylsilyl-tetramethylcyclopentadienyl-tert-butylamido titanium WO93/21242 PCT/US93/0~82 212~S~O

:

- dichloride, dimethylsilyltetramethylcyclopentadienyl- ~
cyclododecylamido titanium dichloride, and the like. ~-For illustrative purpo~es, the above compound~ and those permuted from Table 1 do not include the Lewis base ligand (L). The conditions under which complexes containing Lewis base ligands such as ether or those which form dimers is determined by the steric bulk of the ligands about the metal center. For example, the t-butyl group in Me2Si(Me4Cs)(N-t-Bu)ZrC12 has greater steric requiremQnts than the phenyl group in Me2Si(Me4Cs)(NPh)ZrC12~Et2O thereby not permitting ether coordination in the former compound. Similarly, due to the decreased steric bulk of the trimethylsilylcyclopentadienyl group in tMe2Si(Me3SiCs~3)(N-t-Bu)ZrC12]2 versus that of the tetr~methylcyclopentadienyl group in Me2Si(Me4Cs)(N-t- ~
Bu)ZrC12, the ~ormer compound is dime~ic and the latter ~ ~
is not.
Generally the bridged species of the Group rv B
transition metal compound (ny"~l) are preferred. These compounds can be prepared by reacting a cyclopentadienyl lit`hium co~pound with a dihalo compound whereupon a lithium halide salt is liberated and a monohalo substituent is covalently bound to the cyclopentadi~nyl compound. ~he ~ubstituted cyclopentadienyl reaction product is next reacted with a lith~um salt of a phosphide, oxide, sulfide or amide (for the sake of illustrative purposes, a lithium amide) whereupon the halo element of the monohalo substituent group of the reaction product reacts to liberate a lithium halide salt and the amine moiety of the lithium amide salt is covalently bound to the substituent of the cyclopentadienyl reaction product.
The rçsulting amine derivative of the cyclopentadienyl product is then reacted with an alkyl lithium reagent whereupon the labile hydrogen atoms, at the carbon atom of the cyclopentadienyl compound and at the nitrogen WO93/21242 PCT/US93/0~82 2 1 ~ 0 atom of the amine moiety covalently bound to the substituent group, react with the alkyl of the lithium alkyl reagent to liberate the alkane and produce a dilithium salt of the cyclopentadienyl compound.
Thereafter the bridged species of the Group IV B
transition metal compound is produced by reacting the dilithium salt cyclopentadienyl compound with a Group IV B trancition metal preferably a Group IV B
transition metal halide.
Unbridged spacies of the Group IV B transition metal compound can be prepared fro~ the reaction of a ~-cyclopentadienyl lithium compound and a lithium salt of -an amine with a Group IV B transition metal halide.
Suitable, but not limiting, Group IV B transition met~l compound~ which may be utilized in the catalyst system of this invention include those bridged ~peci~s ("yn=l) wherein the T group bridge is a dialkyl, diaryl - ~-or alkylaryl silane, or methylene or ethylene. ~
Exemplary of the more preferred specieg of hridged ;;~-20 Group IV B transition metal compounds are -dimethylsilyl r methylphenylsilyl, diethylsilyl, ethylphenylsilyl, diph~nylsilyl, ethylene or methylene bridged c~mpounds. ~ost preferred of the bridged ~ ;
species are dimethylsilyl, diethylsilyl and methylphenylsilyl bridged compounds.
Suitable Group IV B transition metal compounds which are illustrative of the unbridged ( ny~=O ) species which may be utilized in ~he catalyst systems of this invention are exemplified by pentamethylcyclopentadienyldi-t-butylphosphinodimethyl hafnium; pentamethylcyclopentadienyldi-t-butylphosphinomethylethyl hafnium; cyclopentadienyl-2-methylbutoxide dimethyl titanium.
To illustrate members 9f the Group IV B transition 35 metal component, select any combination of the species ~-~
in Table 1. An example of a bridged species would be dimethylsilylcyclopentadienyl-t-butylamidodichloro 2129~4'~

zirconium: an example of an unbridged species would be cyclopentadienyldi-t-butylamidodichloro zirconium.
Those species of the Group IV B transition metal component wherein the metal is titanium have been found to impart beneficial properties to a aataly~t system which are unexpected in view of what is known about the properties of bis(cyclopentadienyl) titanium compounds which are cocatalyzed by alumoxane~. Wherea~
titanocenes in their soluble form are generally unstable in the presence of aluminum alkyls, the monocyclopentadienyl titanium metal components of this invention, particularly those wherein the heteroatom is nitrogen, generally exhibit greater stability in the presence of aluminum alkyls and higher catalyst 15 activity rates. -Further, the titanium specie~ of the Group IV B ~;
transition met~l component catalyst of this invention generally exhibit higher catalyst activities and the production of polymers of greater molecular weight than 2~ catalyst systems prepared with the zirconium or hafnium species of the Group IV B transition metal c~ponent.
Generally, wherein it is desired to produce an ~-olefin copolymer which incorporates a high content of ~-olefin, while maintaining high molecular weight polymer the species of Group IV B transition metal compound preferred is one o~ titanium. The most pre~erred species of titanium metal compounds are represented by the formula: ~ / ~
~ ~5>
~ I~

F~ ~ ~ ~ Q
R~ ~ Q
wherein Q, L, R', R, "x" and "w" are as previously defined and Rl and R2 are each independently a Cl to C20 hydrocarbyl radicals, substituted Cl and C20 Wos3r21242 PCT/US93/03482 2 1 2 9 ~ 4 0 ~30-hydrocarbyl radicals wherein one or more hydrogen atom is replaced by a halogen atom, Rl and R~ may also be joined forming a C3 to C20 ring which incorporates the --~ ~
silicon bridge. Suitable hydrocarbyl and substituted ~ -5 hydrocarbyl radicals which may be used as an R' group ~-have been described previously. Preferred R' groups include those bearing primary carbons bonded directly to the nitrogen atom such as methyl, ethyl, n-propyl, ~-~
n-butyl, n-hexyl, n-octyl, n-decyl, n-dodecyl, n-tetradecyl, n-hexadecyl, n-octadecyl, benzyl and the like, and those bearing secondary carbons bonded -~
directly to the nitrogen atom such as 2-propyl, 2-butyl, 3-pentyl, 2-heptyl, 2-octyl, cyclopropyl, -cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, 15 cyclooctyl, cyclododecyl, 2-norbornyl and the like. ~ ~;
Also, the most preferred cyclopentadienyl ring is i~
tetramethylcyclopentadiene (R = Me and x = 4). -~;`
The alumoxane component of the catalyst system is an oligomeric compound which may be represented by the ~-20 general formula (R3-Al-O)m which is a cyclic co~pound, -~
or may be R4(R5-Al-O)m-AlR62 which is a linear compound. An alumoxane i~ generally a mixture of both the linear and cyclic compounds. In the general alumoxane formula R3~ R4, R5, and R6 are, independently a univalent anionic ligand such as a Cl-Cs alkyl radical, for example, methyl, ethyl, propyl, butyl, pentyl or halide and "m" is an integer from 1 to abut 50. Most preferably, R3, R4~ R5 and R6 are each methyl and "m" is at least 4. When an alkyl aluminum halide is employed in the preparation of alumoxane, one or more of R3 6 could be halide.
As is now well known, alumoxanes can be prepared by various procedures. For example, a trialkyl aluminum may be reacted with water, in the form of a moist inert organic solvent; or the trialkyl aluminum may be contacted with a hydrated salt, such as hydrated `
copper sulfate suspended in an inert organic solvent, WO93/21242 PCT/US93/0~82 212~5~3 to yield an alumoxane. Generally, however prepared, the reaction of a trialkyl aluminum with a limited amount of water yield~ a mixture of both the linear and cyclic species of alumoxane.
Suitable alumoxanes which may be utilized in the catalyst systems of this invention are those prepared by the hydrolysis of a alkylaluminum reagent; ~uch as ~ ~
trimethylaluminum, triethyaluminum, tripropylaluminum, ~ -triisobutylaluminum, dimethylaluminumchloride, -~
diisobutylaluminumchloride, diethylaluminumchloride, and the like~ Mixtures of different alkyl aluminum reagents in preparing an alumoxane may also be used.
The most preferred alumoxane for use is methylalumoxane (MAO), particularly methylalumoxanes having a reported average degree of oligomerization of from about 4 to about 25 (~m~=4 to 25) with a range of 13 to 25 being most preferred. ~ `
As an alternative to the alumoxane activation, the metallocene component can be ionically activated using the procedures and techniques ~et forth in Turner et al., U. S. Ser. No. 133,052, filed December 21, 1987;
Turner et al., U. S. Ser. No. 133,480, filed December 22, 1987; Canich et al., U. S. Ser. No. 542,236, filed June 22, 1990; and EP Publication NosO 277,004;
418,044; and 426,637; all o~ which are hereby incorporated by reference. Briefly, for ionic activation, the metallocene has at least one substituent capable of reacting with a proton. The metal~ocene is activated by reaction with a proton-donatin~ cation and a bulky, non-coordinating anion which stabilizes the metal cation formed by the metallocene-proton reaction. Typically, Q in the above formula is hydrocarbyl, the cation is trialkylammonium, for example, and the anion is tetraperfluorophenyl borate, for example.

W093/21242 PCTJUS93/O~B2 2 1 2 ~
-32- ;~
, '' CATAL~ST SYSTEMS `~
The catalyst systems employed in the method of the -~
in~ention comprise a complex formed upon admixture of the Group IV B transition metal component with an activating component. The catalyst system may be prepared by addition of the requisite Group IV B ;-transition metal and alumoxane components, or a ~`
previously cationically activated Group IV B transition metal component, to an inert solvent in which olefin polymerization can be carried out by a solution, slurry or bulk phase polymerization procedure.
The catalyst syst~m may be conveniently prepared by placing the selected Group IV B transition metal component and the selected alumoxane or ionic activating component(s), in any order of addition, in an alkane or aromatic hydrocarbon solvent, preferably -one which is also suitable for service as a polymerization diluent. Where the hydrocarbon solvent utilized is also suitable for use as a polymerization diluent, the catalyst system may be prepared in situ in the polymerization reactor. Alternatively, the catalyst system may be separately prepared, in concentrated form, and added to the polymerization diluent in a reactor. Or, if desired, the co~ponents of the catalyst system may be prepared aR separate solutions and added to the polymerization diluent in a reactor, in appropriate ratios, as is suitable for a continuous liquid polymerization reaction procedureO
Alkane and aromatic hydrocarbons suitable as solvents for formation of the catalyst system and also as a polymerization diluent are exemplified by, but are not necessarily limited to, straight and branched chain hydrocarbons such as isobutane, butane, pentane, hexane, heptane, octane and the like, cyclic and alicyclic hydrocarbons such as cyclohexane, cycloheptane, methylcyclohexane, methylcycloheptane and the like, and aromatic and alkyl-substituted aromatic WOs3/21242 PCT/US93/0~2 21295~0 compounds such as benzene, toluene, xylene and the like. Suitable solvents also include liquid olefins which may act as monomers or comonomers, including ethylene, propylene, l-butene, l-hexene and the like, particularly when the catalyst component~ are prepared as sQparate solutions, in which ca~e prepared catalyst is added to the monomer mixture in the reactor and polymerization is effected e~sentially in neat monomer.
In accordance with this invention optimum results are generally obtained wherein the Group IV B
tran~ition metal compound i~ pre~ent in the poly~erization diluent in a concentration of preferably from abut 0.00001 to about 10.0 millimoles/liter of diluent and the alumoxane component, when used, is pre~ent in an amount to provide a molar aluminum to transition metal ratio of from about 0.5:1 to about 20,000:1. Sufficient solvent i5 normally used so as to provide adequate heat tran~fer away from the catalyst co~ponents during reaction and to permit good mixing.
The catalyst system ingredients, that is, the Group IV B transition metal, the alumoxane and/or ionic activator~, and polymerization diluent, can be added to the reaction vessel rapidly or slowly. The temperature maintained during the contact of the catalyst components can vary widely, such as, for example, from -lOO-C to 300-C. Greater or lesser temperatures can al~o be employed. Preferably, during formation of the catalyst system, the reaction iæ maintained within a temperature of from about 25-C to 100-C, mo~t preferably about 25-C.
At all times, the individual catalyst system components, as well as the catalyst system once formed, are protected from oxygen and moisture. Therefore, the ~-~
reactions are performed in an oxygen and moisture free :;
atmosphere and, where the catalyst system is recovered separately it is recovered in an oxygen and moisture free atmosphere. Preferably, therefore, the reactions WO93/21242 PCT/US93/0~82 ~-2 1 ~ 9 Ji~ ~J

are performed in the presence of an inert dry gas Cuch as, for example, helium or nitrogen. Inhibitor-free monomers are preferred. Thus, any monomer inhibitors can usually be removed from the monomer just prior to S polymerization.
~Q~YMERIZATION PROCESS
In a preferred embodiment of the process of this invention the catalyst system is utilized in the liquid phase (slurry, solution, suspension or bulk phase or combination thereof), high pressure fluid phase or gas phase copolymerization of ethylene and the branched aolefin monomer. These processes may be employed singularly or in series. The ~iquid phase process comprises the steps of contacting a branched ~-olefin monom~r and ethylene with the catalyst system in a suitable polymerization diluent and reacting said monomers in the presence of said catalyst system for a time and at a temperature sufficient to produce a copolymer of high molecular weight. Conditions mo~t preferred for the copolymerization of ethylene are those wherein ethylene is submitted to the reaction zone at pressures of from about 0.019 p~ia to about 50,000 psia and the reaction temperature is maintained ~-~
at from about -100-C to about 300-C. The alumi~um to ~ -transition metal molar ratio is preferably from about 1:1 to 18,000 to 1~ A more preferable range would be 1:1 to 2000:1. The reaction time can be from 10 seconds to 48 hours, or more, preferably from about 10 seconds to about 4 hours.
Without limiting in any way the scope of the invention, one means for carrying out the process of the present invention for production of a copolymer is as follows: in a stirred-tank reactor liquid ~-olefin monomer is introduced, such as 3,5,5-trimethylhexene-1. -~
The catalyst system is introduced via nozzles in either the vapor or liquid phase. Feed ethylene gas is introduced either into the vapor phase of the reactor, WO93/21242 PCT/US93/0~82 2l2s~n or sparged into the liquid phase as is well known in the art. The reactor contains a liguid pha~e composed substantially of liquid ~-olefin comonomer, together with dissolved e~hylene gas, and a vapor phase containing vapors of all monomers. The reactor temperature and pressure may be controlled via reflux of vaporizing ~-olefin monomer (autorefrigeration), as well as by cooling coils, jackets etc. The polymerization rate is generally controlled by the concentration of catalyst. The ethylene content of the polymer product is determined by the ratio of ethylene ~ `
to ~-olefin comonomer in the reactor, which is controlled by manipulating the relative feed rates of these components to the reactor.
In` accordance with another preferred embodiment, the copolymer is prepared by a high pressure process.
The high pressure polymerization is completed at a -temperature from abut 120-C to about 350-C, preferably from about 120-C to about 250-C, and at a preæsure of from about 500 bar to about 3500 bar, preferably from about 800 bar to about 2000 bar, in a tubular or stirred autoclave reactor. After polymerization and catalyst deactivation~ the product copolymer can be recovered using conventional equipment for polymer recovery, such as, for e~ample, a series of high and low pressure separators wher~in unreacted ethylene and branched ~-olefin comonomer are flashed off for recycle to the reactor and the polymer obtained extruded in an underwater pelletizer. An advantage of the high pres~ure process is that the flashing off of the comonomer is relatively effective, particularly at the ratio of comonomer:ethylene used in the -copolymerization to obtain the desired higher comonomer incorporation in the copolymer, in distinction from the available prior art catalyst which required a much higher, generally impractical ratio of comonomer:ethylene to facilitate such a separation and WO93~21242 PCT/US93/0~82 2 ~ 36-recycle (and it was still generally not possible to obtain the high Mw, narrow MMD copolymers of the present invention). Pigments, antioxidants and other known additives, as are known in the art, can be added to the polymer, generally subsequent to the polymerization step.
AS before noted, a catalyst system wherein the Group IV B transition metal component is a titanium species has the ability to incorporate relatively high contents of branched ~-olefin comonomers. Accordingly, the selection of the Group IV B transition metal component is another parameter which may be utili2ed as a control over the ethylene content of a copolymer within a reasonable ratio of ethylene to branched ~-olefin comonomer.
: , CATALYST PR~PARATION EXAMPLE 1 All catalyst preparation and polymerization procedures were performed under an iner~ atmor.phere of 20 helium or nitrogen. Solvent choices were often ~ -~
optional, for example, in most cases either pen~ane or -~
petroleum ether could be interchanged. The choice between tetrahydrofuran (THF~ and diethyl ether was a bit more restrict~d, but in several reactions, either could be used. The lithiated amides were prepared from the corresponding amines and either n butyllithium (n- ~
BuLi) or methyllithium (MeLi). -TetramethylcyClopentadienyl-lithi~m (CsMe4HLi) was prepared according to the procedures of C. ~. Fendrick et al., oraanometallics, l984, 3, Sl9 and F. ~. Xohler and R. H. Doll, Z Natu~forsch, 1982, 376, 144. Other ;~
lithiated substituted cyclopentadienyl compounds were generally prepared from the corresponding cyclopentadienyl ligand and n-BuLi or MeLi, or by ~`
reaction of MeLi with the proper fulvene. TiCl4 was typically used in its etherate form. The etherate was ~-generally prepared by simply adding TiC14 to ether, W093/21242 PCT/US93/~2 2129~ilO

filtering off the solid product and vacuum drying.
TiC14, ZrC14, HfC14, amines, silanes, substituted and unsubstituted cyclopentadienyl compounds or precursors, and lithium reaqents were purchased from Aldrich Chemical Company or Petrarch Systems. Methylalu~oxane was supplied by either Schering or Ethyl Corporation.
C5Me4HLi (10.0 g, 0.078 mol) was slowly added to Me2SiC12 (11.5 ml, 0.095 mol, in 225 ml of THF
solution). The solution was stirred for 1 hour to a~ure a complete reaction. The solvent was then r~moved in vacuo. Pentane was added to precipitate the LiCl. The mixture was filtered through diatomaceous earth and the solvent was removed from the filtrate in vacuo. ~-Tetramethylcyclopentadienyldimethylchlorosilane, (CSMe4H)SiMe2Cl, (15.34 g, 0.071 mol) was recovered as ~-a pale yellow liquid. I ~
(C5Me4H)SiMe2Cl (8.0 g, 0.037 mol) was slowly ;`-added to a suspension of lithium cyclododecylamine (LiHNC12H23) (7.0 g, 0.037 mol, -80 ml THF). The mixture was stirred overnight. The THF was then removed by vacuum to a cold trap held at 196-C. A
mixture of petroleum ether and toluene was added to precipitate the LiCl. The mixture was filtered through diat~maceous earth. The solvent was removed from the filtrate. Tetramethylcyclopentadienyl amidocyclododecyldimethylsilaneO
Ne2Si(CsMe4H)(NHC12H23), (11.8 g, 0.033 mol) was isolated as a pale yellow li~uid~
Me~Si(CsMe4H)(NHC12H23) (11.9 g, 0.033 mol) was diluted with -150 ml of ether. MeLi (1.4 M, 47 ml, 0.066 mol) was added slowly, and the mixture was stirred for 2 hours. The ether was reduced in volume by evaporation. The product was filtered off. The product tMe2Si(CsMe4)(NC12H23)]Li2, was washed with several small portions of ether, then vacuum dried to yield 11.1 g (0.030 mol).

WO93/21242 PCT/US93/0~82 [Me2si(csMe4)(Ncl2H23)]Li2 ~3-0 g, 0.008 mol) was suspended in cold ether. TiC14.2Et2O (2.7 g, 0.008 mol) was slowly added and the resulting mixture was stirred overniqht. The ether was removed via a vacuum to a cold trap held at -196-C. Methylene chloride was added to precipitate the LiCl. The mixture was filtered through diatomaceous earth. The solvent was significantly reduced in volume by evaporation and petroleum ether was added to precipitate the product.
This mixture was refrigerated prior to filtration in order to maximize precipitation. The solid collected -was recrystallized from methylene chloride and Me2si(c5Me4)(Ncl2H23)Ticl2 was isolated (1.0 g, 2.1 mmol).

Polymerization was done in a l-liter autoclave reactor equipped with a paddle stirrer, an external `~
water jacket for temperature control, a regulated ~upply of dry nitrogen, ethylene, propylene, l-butene 20 and hexane, and a septum inlet for introduction of -other solvents or comonomers, transition metal compound and alumoxane solutions. The reactor w~ dried and `
degassed thoroughly prior to use. A typical run consisted of injecting a quantity of freshly di~tilled -solvent (typica~ly toluene), the comonomer and 6.0 ml of 1.0 M methylalumoxane (MAO) into the reactor. The reactor was ~hen heated to 80~C and the transition metal compound solution and the ethylene at a pressure of 4.08 atm were introduced into the system. The polymerization reaction was limited to 30 minutes. The reaction was ceased by rapidly cooling and venting the system, and the resulting polymer was recovered by evaporating the solvent under a stream of nitrogen.
Remaining process run conditions are given in Table 2 including the amount of transition metal catalyst solution (TMC) used, the amou~t of methylalumoxane solution used, thP Al/Ti molar ratio, WO93/21242 PCTIUS93/0~82 _3~_ ?,1295 1~) the amount of toluene and comonomer used, the polymerization temperature, polymer yield, catalyst efficiencies in terms of kg polymer per mole catalyst.atm.hr and kg polymer per mole catalyst.hr and catalyst reactivity ratio.
For example (see Example 2 in Tables 2 and 3), 390 ml of toluene, 6 ml of 1 M MA0 and 10 ml of 3,5,5- ;
trimethylhexene-l were added to the reactor described ~ ;
above. The reactor was heated to 80-C prior to introducing 1.0 ml of the catalyst stock solution made by dissolving 13.5 mg of the transition metal compound in 10 ml of toluene. The reactor was then immediately pressurized with 4.08 atm of ethylene. The -polymerization reaction was limited to 30 minutes after which time the reaction was ceased by rapidly cooling and venting the system. The resulting polymer (40 g) was recovered by ~olvent evaporation and drying în a vacuum at 30-60-C, typically 50-60-C for 48 hours to 5 days. Catalyst productivity was calculated at 6,950 (kg polymer/mol TMC.atm.hr) and 28,_54 (kg polymer/mol TMC.hr). Polymer characteristics include a GPC/DRI PE
molecular weight of 103,500 daltons, a molecular weight distribution of 3.6, 2.5 mole percent incorporat~d 3,s,5-trimethylhexene 1 gi~ing a catalyst reactivity ratio of 24.6 ethylene to 3,5,5-trimethylhexene-1, a polymer density of 0.930 g/ml, and a melting point of 114-C.

W O 93/21242 . PC~r/US93/03482 2 ~ ~9~3~

TABI~E 2 Ex. Ol-t1n ~C ~C ~C ~ ~ Oletin _ _ ; _ U~ Stod~ Stoek Stock ~ t-l) _ t1~1tr tlt~ t~
(~J U~d U~-d 011~ ~'bld I'h~ C ~ ' 10 1~ tol) (~ ~C3 rt hr) P~l _ . . . _ -- _ ~llC ~Ir) 23 ,S ,5- 1~.5 ~ 1 .35 2t2~390 ~0 ~ _ 2~,35~ :tr~thyl .
h-~ne- 1 _ _ .
3},5,5- 13.S ~ 1.35 2127 380 20 ~ ~170 ~ 17,01 -he~l _ _ ': ~
;

~ :

Resulting polymer characteristics are given in -~
Table 3 including weight average ~olecular weight, molecular weight distribution, comonomer concentration, polymer density, ~elting point and secondary phase transition te~perature (T2). ~-t~ . Ole~ ~n . . _ ~ rl Pol~er --~2b ~- 5tr~ I n Vs-d Cdal~~) O~al~;n D~ty t-C) C~ lu~ 3r~tX~k _ ___ _ . .,, _ __ __ _ _. __ __ _ _ . . ... . ~ . _ . __ 2 3,5,S- 10~,S00 ~.~ 2.S 2~.o 0.930 11~ SO ~2~ Sr7 th1X~tb~l~ , , ___ __ ._ .. __ 3 3,S,5- ~ 0 2.5 2.1 58~ 0.931 1~ 62 . ..
trinethyl-hexo~r1 _ _ _ ~ . .

WO93/21242 PCT/US93/0~82 21295(1o The gel permeation chromatography ~GPC) data for the present copolymer is very unusual in that th~ Mw as determined by GPC with differential refractive index -S (DRI) measurement yielded artificially low results as compared to the more accurate (but more difficult) viscosity (VIS) measurements. This is apparently due `
to the size of the comonomer side chain distributed throughout the polymer backbone.
The stress-strain properties of the Example 2 ' copolymer as reported in Table 3 indicate that the copolymers are extremely tough materials. The modulus of elasticity is very high, and the strain to break is unusual in that it is also high. See Fig. 10 When the material of Example 2 was evaluated in a conventional Instron tensile testing machine, it exhibited unusual strain hardening to the extreme point where the material stiffened and pulled out of the specime~ ;
holder before any break could be observed.
Measurements of viscoelastic properties were performed using a PHEOMETRICS SYSTE~ IV rheometer or a POLYMER LaBORATORIES DMTA rheometer. Isothermal measurements were performed on the SYSTEM IV rheometer over a wide range of tamperatures. Isochronal experiments were conducted at a frequency of 10 rad/s and 1 Hz on the SYSTEM IV and the DMTA rheometer, respectively. The storage ~odulus (E'~ is determined according to a Polymer Laboratories, Inc. dynamic mechanical thermal analyzer (DMTA) procedures at ambient temperature. The specimen is cast in a Teflon-coated mold, and ~2 mm diameter disks are die cut for DMTA testing. E' is understood in the art to be a measurement of the elastic or storage modulus (stress/strain) measured in phase with sinusoidal torsional displacement of the material.
The unusual characteristics of the present copolymers are also seen in the storage modulus (E'), W093/21242 PCT/US93/0~82 21 2 ~ S 'I O -42-loss modulus (E") and tan ~ data developed for Example 3 and Fig. 2.
Many modifications and variations besides the :
embodiments specifically mentioned may be made in the compositions and methods described herein without substantially departing from the concept of the present invention. Accordingly, it should be clearly :
understood that the form of the invention described herein is exemplary only, and is not intended as a -~
limitation of the scope thereof.
..
,

Claims (15)

What Is Claimed Is:

1. A copolymer having an Mw of about 30,000 to about 1,000,000 and an Mw/Mn of 4 or less, comprising ethylene and about 2.0 mole% of an .alpha.-olefin comonomer, said comonomer having at least two branches.

2. The copolymer of claim 1, wherein the comonomer having two or more branches has at least one alkyl branch immediately adjacent to the .alpha.-olefinic unsaturation thereof.

3. The copolymer of claim 7, wherein the alkyl branch has from 1 to 3 carbon atoms and is closer to the .alpha.-olefinic unsaturation than a terminal carbon of the longest

4. The copolymer of any of the above claims wherein the copolymer is a copolymer of ethylene and from about 2.0 to about 10 mole% of a C6 to C30 .alpha.-olefin, preferably a C6 to C14 a-olefin comonomer having 2, 3, or 4 branches, wherein at least one of the branches is a C3 to C5 alkyl and is closer to the .alpha.-olefin unsaturation than a terminal carbon atom in the longest straight chain of the comonomer.

5. The copolymer of any of the above claims, wherein the branching includes from one to four branches selected from methyl, ethyl, propyl and isopropyl.

6. The copolymer of any of the above claims having an MWD between about 2 and about 4.

7. The copolymer of claim 1 or 10, wherein the comonomer is selected from 3,4-dimethylpentene-1, 4-methyl-3-ethylpentene-1, 4,4-dimethyl-3-ethylpentene-1, 3,4-dimethylhexene-1, 3,5-dimethylhexene-1, 4-methyl-3-ethylhexene-1, 5-methyl-3-ethylhexene-1, 3-methyl-4-ethylhexene-1, 4-methyl-3-propylhexene-1, 5-methyl-3 propylhexene-1, 3,4-diethylhexene-1, 4-methyl-3-isopropylhexene-1, 5-methyl-3-isopropylhexene-1, 3,4,4-trimethylhexene-1, 3,4,5-trimethylhexene-1, 3,5,5-trimethylhexene-1, 4,4-dimethyl-3-ethylhexene-1, 4,5-dimethyl-3-ethylhexene-1, 5,5-dimethyl-3-ethylhexene-1, 3,4-dimethyl-4-ethylhexene-1, 3,5-dimethyl-4-ethylhexene-1, 4-methyl-3,4-diethylhexene-1, 5-methyl-3,4-diethylhexene-1, 3-methyl-4,4-diethylhexene-1, 3,4,4-triethylhexene-1, 4,4-dimethyl-3-propylhexene-1, 4,5-dimethyl-3-propylhexene-1, 5,5-dimethyl-3-propylhexene-1, 4,4-dimethyl-3-isopropylhexene-1, 4,5-dimethyl-3-isopropylhexene-1, 5,5-dimethyl-3-isopropylhexene-1, 3,4,4,5-tetramethylhexene-1, 3,4,5,5-tetramethylhexene-1, 4,4,5-trimethyl-3-ethylhexene-1, 4,5,5-trimethyl-3-ethylhexene-1, 3,4,5-trimethyl-4-ethylhexene-1, 3,5,5-trimethyl-4-ethylhexene-1, 4,5-dimethyl-3,4-diethylhexene-1, 5,5-dimethyl-3,4-diethylhexene-1, 3,5-dimethyl-4,4-diethylhexene-1 and 5-methyl-3,4,4-triethylhexene-1.

8. The copolymer of any of the above claims having a composition distribution breadth index of at least about 50 percent.

9. The copolymer of any of the above claims, wherein the molecular weight is from about 80,000 to about 500,000 daltons.

10. A film, fiber or molded article of any of the above copolymers.

11. A method for preparing a copolymer of ethylene and a branched a-olefin comonomer having two or more branches, comprising contacting a mixture of ethylene and the comonomer with a catalyst at polymerization conditions wherein the ethylene:comonomer reactivity ratio is less than about 75, preferably less than 50, more preferably between 25 and 50.

12. The method of claim 11, wherein the branched .alpha.-olefin comonomer has from 6 to 14 carbon atoms and has at least two branches selected from methyl, ethyl, propyl and isopropyl.

13. The method of claim 11 or 12, wherein the catalyst is a catalyst system including a metallocene catalyst component and an activating component for activating the metallocene component, wherein the metallocene component has the formula:

or wherein M is Zr, Hf or Ti in its highest formal oxidation state:
(C5H5-y-xRx) is a cyclopentadienyl ring which is substituted with from zero to five substituent groups R, "x" is 0, 1, 2, 3, 4 or 5 denoting the degree of substitution, and each substituent group R is, independently, a radical selected from a group consisting of C1-C20 hydrocarbyl radicals, substituted C1-C20 hydrocarbyl radicals wherein one or more hydrogen atoms is replaced by a halogen radical, an amido radical, a phosphido radical, an alkoxy radical, an alkylborido radical or a radical containing a Lewis acidic or basic functionality; C1-C20 hydrocarbyl-substituted metalloid radicals wherein the metalloid is selected from the Group IV A of the Periodic Table of Elements; and halogen radicals, amido radicals, phosphido radicals, alkoxy radicals, alkylborido radicals, or a radical containing Lewis acidic or basic functionality; or (C5H5-y-xRx) is a cyclopentadienyl ring in which two adjacent R-groups are joined forming C4-C20 ring to give a saturated or unsaturated polycyclic cyclopentadienyl ligand;
(JR'z-1-y) is a heteroatom ligand in which J is an element with a coordination number of three from Group V A or an element with a coordination number of two from Group VI A of the Periodic Table of Elements, each R' is, independently a radical selected from a group consisting of C1-C20 hydrocarbyl radicals, substituted C1-C20 hydrocarbyl radicals wherein one or more hydrogen atoms is replaced by a halogen radical, an amido radical, an alkylborido radical, a phosphido radical, an alkoxy radical, or a radical containing a Lewis acidic or basic functionality; and "z" is the coordination number of the element J;
each Q is, independently, any univalent anionic ligand, provided that where Q is a hydrocarbyl such Q is different than the (C5H5-y-xRx) or both Q together are an alkylidene, a cyclometallated hydrocarbyl or a divalent anionic chelating ligand;
"y" is 0 or 1 when "w" is greater than 0; "y" is 1 when "w" is 0; when "y" is 1, T is a covalent bridging group containing a Group IV A or V A element;
L is a neutral Lewis base where "w" denotes a number from 0 to 3.

14. The method of claim 13, wherein the activating component comprises an alumoxane.

15. The method of claim 13 or 14, wherein said reactor change further includes a termonomer, preferably a C3 to C8 termonomer.