CA1272846A - Molecular weight distribution modification in a tubular reactor - Google Patents

Abstract

ABSTRACT OF DISCLOSURE
MOLECULAR WEIGHT DISTRIBUTION MODIFICATION
IN A TUBULAR REACTOR
Polymer having a polymodal MWD ethylene copolymer are prepared by conducting the polymerization in a substantially mix free reactor using an essentially transfer agent free reaction mixture, the reaction being carried out in a manner such that the propagation of es-sentially all copolymer chains is initiated simulta-neously. In carrying out the process of this invention, the catalyst components are premixed and aged prior to introduction into the reactor. The process is pref-erably carried out in a tubular reactor using VCl4 and aluminum sesquichloride as the catalyst system.

Description

~O'ECULAR I~IG~T DISTP~IBUTIO;~ ~ODIFICATIO~
I~' TUBULAR REACTOR
Eeck~round of the Invention The present invention relates to no~el co-poly~ers o_ alpha-olefins. More specifically, it re-12;es to novel copolymers of e~hylene with other Glrha-olefins which have a polymodal molecular weight etctribution wherein indiv.dual nodes comprising t~e`~
po'y~er have narrow molecular weight distributions.
For convenience, certain ter~s that are re-peeeed throughout the present specification are defined.
below:
(a) Inter-CD de~ines eompositional variation, in terms of ethylene content, among poly~er chains. It -s expressed as the minimu~ deviction tanalogous to a stendard deviation) in terQs of weight percent ethylene ~rom the average ethylene composition for a given co-po'~-~er sa~ple needed to inclu~e 2 given ~eight percent of the total copolymer sample -~hich is obtained by ex-cluding equal weigh~ fraetions from both ends of the distribution. ~he deviation need not be symmetrical.
~nen expressed as a single n~ber, for example, 15Z
Inter-CD, it shall mean the larger of the positive or ne~ative ~eviations. For :e~,e;;~ple, ~or a Gaussian corl~po-sitional distribution, 95.5Z of the polymer is within 20 ~t~ ethylene o~ the ~ean if ~he standard deviation is 10~. The Inter-CD for 95~5 wtZ of the polymer is 20 wt%
e~hylene for such a s2rople.
(b) Intra-CD is the co~positional variation~
in terms oS ethylene, ~ithi~ a copolymer chain. It is .

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expressed as the minimum difference in weight (wt) Z
ethylene ehat exists between two portions of a single copolymer chain, each portion comprising at least 5 wtZ
of the chain~
(c) Molecular weight distribution (I~) is a measure of the range of molecular weights within a given copoly~er sample. It is characterized in terms of at least one of the ra~ios of weight average to number av-erage moleculax weigh~, MW/Mn, and Z average to weight average molecular weight, Mz/ ~ , where: Mw = ~NiMi2 Mn = NiMi, and M = ~ NiMi3, and Z ~ iMi2 Ni is the number of molecules of weight Mi.
Ethylene-propylene copolymers, particularly elastomers, are important commercial products. Two basic types of ethylene-propylene copolymers are co~mer-cially available; ethylene propylene copolymers and ethylene propylene terpolymers~ Ethylene-propylene co-polyners ~EPM) are saturated compounds requiring vulcan-ization with free radical generators such as organic peroxides. Ethylene-propylene terpol~ers (EPDM) con-tain a small amount of non-conjugated diolefin, such as dicyclopentadiene; 1 ,4-hexadiene or ethylidene nor-bornene, which provides sufficient unsaturation to per-mit w lcanization with sulfur. Such ethylene-propylene poly~erc that include ae least two monomers, i.e., EP~
and EPDM, will be hereinaf~er collectively referred to as et~ylene-propylene copolymers.
These copolymers ~ave outstanding resistance to weathering, good heat aging properties and the abil-ity to be compounded with large quantities of fillers ~ , . . .
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-and plasticizers- resulting in low cost compounds which are particularly useful in automotive and industrial mechanical goods applications. Typical automotive uses 2re tire sidewalls, inner tubes, radiator and heater hose, vacuum tubing 9 weather stripping, sponge doorseals and Viscosity Index (V.I.) improvers for lubricating oil compositions. Typical mechanical goods uses are for ap-pliance, industrial and garden hoses, botk molded and e~cruded sponge parts, gaskets and seals and conveyor belt covers. These copolymers also find use in adhe-sives, appliance parts as in hoses and gaskets, wire and cable and plastics blending.
As can be seen from the above, based on their respective properties, EPM and EPDM find many, varied uses. It is known that the properties of such copoly-mers which make them useful in a particular application are, in turn, determined by their composition and struc-ture. For example, the ultimate properties of an EPM
and EPDM copolymer are determined by such factors as co~position, compositional distribution, sequence dis-` tribution, molecular weight, and molecular weight dis-tribution (~D).
The efficiency of peroxide curing depends on composition. As the ethylene level increases, it ~an be shown that the "ch~mical" crosslinks per peroxide mole-cule increases. Ethylene content also influences the rheological and processing properties, because crystal-linity, which acts as p~ysical crosslinks, can be intro-duced. The crystallinity present at very high ethylene contents may hinder processability and may make the cured product too "hard" at temperatures below the crys-talline melting point to be useful as a rubber.
Milling behavior of EPM or EPDM copolymers varies radically with MW~. Narrow ~D copol~mers crum-ble on a mill, whereas broad M~ materials will band un-der conditions encountered in normal processing opera-tions. At the shear rates encountered in processing - ' :

equipment, broader MWD copolymer has a substantially lower viscosity than narrower MWD copolymer of the same weight average molecular weight or low strain rate vis-cosity. Thus, there exists a continuing need ~or dis-covering polymers with unique properties and compositions.
For elastomer applications the processability is often measured by the Mooney viscosity. The lower this quantity the easier the elastomer is to mix and fabricate. It is desirable to have low Mooney yet to maintain a high number average molecular weight, Mn, so that the polymers form good rubber networks upon cross-linking. For EP and EPDM, narrowing the molecular weight distrib-~tion results in the production of polymer with higher number average molecular weight a-t a given Mooney than the broader distribution polymer. In cer-tain cases, the poor milling, calendering or extrusion behavior that results from the narrow MWD must be ame-liorated. _Rather than perform a MWD broadening which includes low molecular weight components which reduce Mn~ it is possible to broaden the MWD without dispropor-tionately lowering Mn. This is done by superposing one or more narrow MWD modes, i.e., different Mooney compo-nents, each of which contains no appreciable amount of low molecular weight polymer. The result is a polymodal molecular weight distribution comprised of narrow ~WD
polymer fractions of different molecular weights.
The present invention is drawn to a novel co-polymer of ethylene and at least one other alpha-olefin monomer which copolymer is composed of several such MWD
components each of which is very narrow. It is well known that the breadth of the MWD can be characterized by the ratios of various molecular weight averages. For example, an indication of the narrow MWD of each compo-nent in accordance with the present invention is that the ratio of weight to number average molecular weight (MW/M ) is less than 2. Alternatively, a ratio of the ~;1 . - ---, ~ ` : ' ' .

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7~ ~ ~6 Z-average molecular weight ~o the weight average molecu-lar weight (Mz/ ~ ) of less than 1.8 typifies a narrow in accordance with the present invention. It is known that the property advantages of copolymers in ac-cordance with the present invention are rela~ed to these ratios. Smail weight fractions of material can dispro-portionately influence these ratios while not signifi-cantly al~ering the property advantages which depend on them. For instance, the presence of a small weight ~raction (e.g.~ 2Z) of low molecular weight copolymer can depress Mn, and thereby raise ~IW/Mn above 2 while maintaining Mz/ ~ less than 1.8. Therefore, the compo-nent polymers, in accordance with the present invention, are characterized by having at least one of two charac-teristics; ~ /M~ less than 2 and Mæ/ ~ less than 1.8;
To o~tain naxrow M~, the copolymers in accordance with the present invention are preferably made in a tubular reactor. It has been discovered that to produce such copolymers requires the use of numerous heretofore un-disclosed method steps con~ucted within heretofore un-disclosed preferred ranges. Accordingly, the present invention is also drawn to a method for making th~ novel copolymers of the present invention.

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Representative prior art dealing with tubular reactors to make copolymers are as follows:
In "Polymerization o ethylene and propylene to amorphous copolymers with catalysts of vanadium oxy-chloride and alkyl aluminum halides"; E. Junghanns, A.
~umboldt and G. Bier; Makro~ol. Chem, v. 58 ~12/12/62~:
18-42, the use of a tubular reactor to produce ethylene-propylene copolymer is disclosed in which the composi-tion varies along the chain length. ~ore specifically~
~his reference discloses the production in a tubular reactor of amorphous ethylene-propylene copolymers using Ziegler catalysts prepared from vanadium compound and aluminum alkyl. It is disclosed ~hat at the beginning of the tube ethylene is preferentially polymerized9 and if no additional ma~e-up of the nonomer mixture is made during the polymerization the concentra~ion of monomers changes in favor of propylene along the tube. It is Lurther disclosed that since these changes in concentra-tion take place during chain propagation, eopolymer chains are produced which contain more ethylene on one end than at the other end. It is also disclosed that copolymers made in a tube are chemically non-uniform, but fairly uniform with respect to molecular weight dis-~ribu~ion. Using t~e data reported in their Figure 17 Cor copolymer prepared in the tube, it ~-as estimated ~hat the ~ /Mn ratio for this copolymer was 1.6.
"Laminar Flow Polymerization of EPD~ Polymer";
J.F. Wehner; ACS Symposium Serîes 65 (1978); pp 140-152 discloses th~ results of co~puter simulation work under-taken to determine the effect of tubular reactor solu~
tion polymerization with Ziegler eatalysts on the molec-ular weight distribution o~ the polymer produc~. The speci~ic polymer simulated was a~ eiastomeric terpolymer of ethylene-propylene-l, 4-hexadiene. On page 149, it is stated that sinee the ~onomers have dirferent reac~
tivities, a pol~mer of varying composition is obtained - - ~ ; , . ..
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as the monomers are depleted. However, whether the com-position varies inter- or intramolecularly is not dis-tinguished. In Table III on page 148, various polymers having ~ /Mn f about 1.3 are predictcdO In the third paragraph on page 144, it is stated that as the tube di-aneter increases, the polymer molecular weight is too low to be of prac~ical interes~, and i~ is predicted that the reactor will plug. It is implied in the fixst paragraph on page 149 that the compositional dispersity produced in a tube would be detrimental to product qual-ity.
U.S. 3,681,306 is drawn to a process for producing ethylene/higher alpha-olefin copolymers having good processability, by polymerization in at least two consecuti~e reactor stages. According to this refer-ence, ~his two-stage process provides a simple poly~eri-z~tion process that permits tailor-making ethylene/
alpha-ole~in copolymers having predetermined properties, particularly those contributing to processability in co~mercial applications such as cold-flow, high green strength and millability. Allegedly, the disclosed pro-cess is par~icularly adapted ~or producing elastomeric copolymers, such as ethylene/ propylene/5-ethylidene-2-norbornene, using any of the coordination catalysts use-~ul for making EP~I. The preferred process uses one tubular reactor followed by one pot reactor. However, it is also disclosed that one tubular reactor could be used, but operated at diferent reaction conditions to si~ulate two stages. As is seen from the disclosure at column 2~ lines 14-20, the process makes polymers of broader r~D than those made in a single sta~e reac~or.
Al~hough intermediate polymer from the first (pipeline) reactor is disclosed as having a ratio of M~tMn o~ about

2 (column 5, lines 54-57) the ~inal polymers produced by the process have an Mw/ ~ of 2.4 ~o 5.
U. S. 3, 6?5, 658 to Closon discloses a closed circui~ tubular reactor apparatus with high 7~

recirculation ra~es of the reactants which can be used to make elastomers of ethylene and propylene. With par-ticular reference to E'ig. 1 of th~ patent, a hinged sup-port lO for vertical leg 1 of the reactor allows for horizontal expansion of ~he bottom leg thereof and pre-vents harmful de~ormations due to ther~al expansions, particularly those experienced during reactor clean out.
U~S. 4,065,520 ~o Bailey et al. discloses thP
use of a batch reactor to make ethylene copolymers, in-cluding elastomers, having broad composi~ional distribu-~ions. Several feed tanks for the reactor are arranged in series, with the feed to each being varied to make the polymer. The products made have crystalline to se~i-crystalline to amorphous regions and gradient ch2n~es in between. The catalyst sys~em can comprisë
vanadium compounds alone or in combination with titanium coEpounds and is exemplified by vanadium oxy-tri-chlo-ride and diisobutyl aluminum chloride. In all of the examples, titanium compounds are used. In several exam-ples, hydrogen and diethyl zinc, known transfer agen~s, are used. The polymer chains produced have a cor;posi-tionally disperse first length and uniform second length. Subsequent lengths have various other CoQposi-~ional distributions.
` In "Estimation of Long-Chain Branching in Ethylene-Propylene Terpolymers from Infinite-Dilution Viscoelastic Properties"; Y. Mitsuda, J. Schrag, and J.
Ferry; J. Appl~ Pol. Scl.~ 18, 193 (1974) narrow ~ co~
polymers of ethylene-propylene are disclosed. For exam-ple, in TABLE II on page 198, EPDM copolymers are dis-closed which have ~ /~n of from l.lg to 1.32.
In "The Effect o~ Molecular Weight and Molecu~
lar Ueight Distribution on the Non-~ewtonian Behavior of ~tkylene-Propyle~e-Diene Polymers; Trans. SocO Rheol., 14, 83 (1970); C.K. Shih, a ~hole series of composi~ion-ally homogeneous fractions were prepared and disclosedO
For example, the d~ta in TABLE I discloses polymer .

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_9_ S2-~ple B as naving a high de~ree of homogeneity. Also, based on the reported data, the ~ of the sample is very narrow. Howe-Jer, the poly~ers are not disclosed as heting intraDolecular dispersity.
Molecular weight ~is~ribution (~I~) is a very i ?ortant characteris~ic of ethylene-propylene copoly-~e-s and terpolymers. Favorable distributions result in polymers which can have both f2ster cures and better processing characteristics. An opti~um coDbination of t~.ese properties is achieved ~here the polymers have a polymodal molecular weight distribution and a polymodal compositional distribution.
A significant amount of effort ~2S been ex-pe-.ded by the polyuer industry in an atte~pt to produce su^h poly~odal ethylene-propylene polymers. Generally, th.ese efforts have been directed toward physical blends of poly~ers having different ~;~ or by sequential poly-merization in a multiple reactor system. For example~ a poly~erization is carried out in a first reaction stzge to produce a polymer of a particular 2~WD and composition ~-ith a subsequent polymerization in a second reactor stêge to produce a poly~er of a different ~.~ from that o the first stage and, if desired, of a ~ifferent mono-~e- composition. Representêtive prior 2rt dealing with t~.e preparation of bimodal ~.~ ethylene-propylene co-po1y~ers are as follows:
British Patent ~o. 1,233,599 is illustrative o~ t~o stage polymeri2ation processes. I~ile copolymers of ethylene are incidently disclosed, the exa~ples and disclosure are directed tow2rd polyethylene homopolymers 2nd crystalline copoly~ers, e.g.~ 95~ ethylene. The p-eferred catalysts are vanadium compounds such as vcr~yl halide, van2dium tetrachloride or vanadium tr-s-(aeetyi-acetonate) in conjunction ~ith an aluminum ~c=pound, e.g., Br2AlCH Br2. The different ~s are ob-te_ned by using differing ~mounts of h~drogen in the ~-rst and second stage poly~erization.

: : ` .'' UOS. Patent No. 4,078,131 discloses an ethyl-ene-propylene rubber ~omposition having a bimodal dis-tribution in molecular weights comprising ~wo polymer fractions each having a wide distribution of molecular weig~ts and a monomer composition different from that of the other principal fractions. The polymers are further characterized in ~ha~ they are formed of: (a~ a first principal fraction ~omprising from about 30Z to about 85Z ~by weight referred to the total weight of elasto-mers) of molecular weight fractions having an intrinsic viscosity dis~ribution of from about 0.2 to about 3, and average intrinsic viscosity between about 0.8 to about 1.5 t an average propylene content between abou~ 36 to about 52% by weight, and a termonomer content of between 0% and about 5Z, and of (b) a second fraction comprising about 70% to about 15Z by weight of molecular weight fractions having an intrinsic viscosity distribution ~rom about 3 to about 15, an average intrinsic viscosity of about 3.5 to about 7, and average propylene content of between about 26~ to about 32~ by weight and a ter-monomer content of about 0 to about 5%.
The polymers are prepared by carrying out polymerization in two separate reactors connected in se-ries. The catalyst systems utilized include organic and inorganic component of a transition metal of Group 4A to 8A o~ the Mendeleev periodic table of the elements, e.g., VOC13, VCl4, vanadium esters and acetyl aceton-ates. Co-catalysts include organoaluminum compounds or mixtures of compounds, e.g., aluminum alkyls.
U.S. Patent 3,681,306 discloses a two stage polymerization process for the preparation of ethylene-propylene co~and terpolymers. In one embodiment the first stage is a "pipe reactor" and t~e second stage is a bac~-mixed pot reactor. The polymerization is carried out so that the average ethylene/alpha olefin ratio in one state is at least 1.3 ti~es the avera~e ratio o~ the other s~age. Any of the coordination ca~alysts know ~o .

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be useful in producing EPDM polymers is said to be ef fective for the process.
U.S. Patent No. 4,~59,468 discloses a broad ~olecular weight ethylene-propylene-diene rubber pre-pared using as a catalyst (a) the alcohol reaction prod-uct of vanadium oxytrichloride and (b) a mixture of alu-minum sesquichloride and ethylaluminum dichloride. The polymer is characterized in that the higher molecular weight fraction con~ains a larger proportion of the diene than does the lower molecular weight fraction.
The polymer has an intrinsic viscosi~y of about 1.0 to about 6.0 dl/g and a weight average molecular weight/
number ra~io of about 3 ~o about 15.
U.S. Patent No. 4,306,401 discloses a method of manufacture of EPDM type terpolymers ~hich utilizes a two stage polymerization process. Substantially all of the non-conjugated diene monomer is fed to the first stege thereby producing a poly~er having a non-uniform diene content.

Brief Description of the Drawin~s The accompanying drawings depict, for illus-tration purposes only, processes e~bodied by the present invention, ~herein:
Fig. 1 is a schematic representation of a pro-cess ~or producing polymer in accordance with the pre-sent invention.
Fig. 2 schematically illustrates a polymodal ~WD poly~er comprising narrow MWD polymers for each mode, Fig. 3 is a graphical illustration of a tech~
nique for determining Intra-CD of a copolymerD
Fig. 4 graphically ~llustrates various copoly-~er structures that can be a~tained USillg processes in accordance with the present invention.

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Deta~led Descr~tion of the Inven~ion The instant invention relates to a noYel co-polymer of ethylene and at least one other alpha-olefin monomer, whi~h copolymer is a superposition of t~o or ~ore copolymers, each of which has a 1,~ characterized by having at least one of t~o characteristics; an ~Iw/Mn of less than 2 and Mz/ ~ of less than 1.8.
As already noted, copolymers in accordance ~i~h the present invention are comprised of ethylene and ~t least one other alpha-olefin. Such alpha-olefins can include those containing 3 to 18 carbon atoms. Alpha-olefins of 3 to 6 carbons are preferred beca~se o~ eco-no-~c considerations.
Illustrative non-limiting examples of alpha ole ins userul in the practice of this invention are pro~ylene, butene-l, pentene-l, hexene-l, h~ptene-l, oc ene-l, dodecene-l, etc. The ~st preferred copoly-mc s in accordance with the present in~ention are those co-2rised of ethylene and propylene or ethylene, propyl-ene and non-conjuga~ed diene.
As is ~ell known to those skilled in the art, co?olymers of ethylene and higher alph2-olefins such as propylene often include other polymerizable monomers.
T~ical of these other monomers can be non-conjugated GieneS. Illustrative non-l~iting exa~ples of such no~-conjugated dienes are:
a. straight chain acyclic dienes such as:
1l4-hexadiene; 1,6-octadiene;
b. branched chain acyclic dienes such as:
5-methyl-1, 4-hexadiene; 3,7 dimethyl-l, 6-`octadiene; 3,7-di~thyl-1,7-octadiene and the mixed isomers of dihydro-myrcene;

c. single ring 21icyclic diene~ such as:
1,4-cyclohexadiene; 1,5-cyclooctadiene; and 1,5-cyclododecadiene;
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d. m~lti-ring alicyclic fused and bridg~d ring dienes such as: tetrahydroindene;
~ethyltetra~ydroindene; dic~clopent~diene; bi-cyclo-(2,2,1)-hepta-2,5-diene; alkenyl, alkyl-idene, cycloalkenyl 2nd cycloalkylidene nor-bornenes such es 5-methylene-2-norbornene ~ , 5-ethylidene-2-norbornene (E~B~, S-pro-pylidene-2-norbornene, 5-isopropy~idene-2-norbor-nener 5-(4-cyclopentenyl)-2-norbornene; S-cyclo-he~ylidene-2-nor~ornene.

Of t'ne non-conjug2ted dienes typica ly used to pr~p2re these copolymers, dienes containing at least one of the double bonds in a strained rin~ zre preferred.
The ~ost prelerred diene is 5-ethylidene-2-norbornene (E`~). The a~ount of diene (wt. basis) in the copolymer ca~ be about 0% to 20Z with OZ to 15% being-preferred.
The nost pre~erred range is OZ to 10~.
As already noted, the ~ost preferred copolymer in cccordance with the present invention is ethylene-pr~p~lene or ethylene-prop;~lene non-conJugated diene.
In either event, the avera&e et~ylene content of each co=ponent of these copolymers can be 2S low as about la%
on a ~eight basis. The prererred ~inimum ethylene ~on-te~ is about 25%. A more preferred ~ini~um is abou~
30n~ The maxim~m ethylene oontent can b~ about 90% on a weight basis. The preferred maximum is abou~ 85~, with the ~ost pre.erred being about 80~
The molecular weight of the component copoly-~er ~ade in accordance witb the present invention can ~2'~ over a wide range. The weight average molecular ~e_ght ~ ) can be as low as about 2~000O The ~referred mi..i~um is about 10,000. The most preferred minimum is cbout 20,000. The maximu~ weight a~erage molecular ~e_ght can ~e as high as 2bout 12,000,000. The pre-ferred maximum is about 1,~00,000. The most preferred ~:i~um i~ about 75G~QOOo .
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' Another feature of the copolymers made in ac-co-2ance with the present invention is that the ~olecu-ler weight distribution (~D) of each component is very n~rrow, as characterized by having at least one of two c..eracteristics; a ratio of ~W/Mn of less than 2 2nd a r~tio of Mzt~ of less thzn 1.8. The ~/1~n ratio for t~ hole copolymer can range fro~ about 1 to about 50.
Tr.e ~w and 1~ of the copol~er is controlled by adjust-the ~ and weight fraction of polymer that make uptr.e individual narrow ~ ~ components. In a preferred e-.~odiment, the Mw of any t~o adjzeent ~h~ modes should di~fer by at least 50% and any one mode ~hould com-p-ise at least 10 wtZ of the total copolymer. As it re-lc es to EPM and EPDM, a t~pical advantage of such co-pcl~ners conposed of several Dodes having narrow ~ is t~t when co~pounded and t~lcznized, faster cure and b~.~er physical properties result than ~hen copolymers hê~ing lower Mn for a given ~ooney are used.
Processes in accordance with the present in-~ntion produce copolymer by polymerization of a reac-.ion mixture comprised of catalyst, ethylene, at least o..e additional alpha-ole~in ~onomer, and optionally, a nc~- conju~ated diene. Solution polymerizations are preferred.
Any kno~ solvent for the reaction mixture t~.ct is effective for the purpose can be used in con-d~cting solution polymerizations in accordance with the p-esent invention. For exa~ple, suitable solvents are h;;~rocarbon solvents such 2S aliphatic, cycloaliphatic 2nd aromat;c hydrocarbon solvents, or halogenated ana-lc~s of such solvents. The preferred solvents are C4 to Cl~, straight chain o~ branched chain, saturated hydro cc-bons, C5 to Cg saturated alic~clic or aro~atic hydro-cæ-bons or C2 to C6 halogenated hydrocarbons. Most pre-ferred are C6 to C12~ straight chain or branched c~ain h;~rocarbons, p~rticularly hexane. Nonlimiting illus-t2ctive examples of such solvents are butane, pent2ne, .

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hexane, heptane, cyclopentane, cyclohexane, cyclohep-tane, methyl cyclopentane, methyl cyclohexane, isooc-tane t benzene, toluene, x~lene, chloroform, chloro-benzenes~ tetrachloroethylene, dichloroethane and trichloroethane.
A number of processes can be used to prepare the copolymer products of this invention. These pro-cesses are based on carrying out the copoly~erization in a batch or tubular reactor. As described in our co-pending patent application, Serial Number ~04~582, co-polymers of narrow MWD with MW/Mn less than 2.0 or Mz/Mw less than 1.8 can be obtained by operating such reactors at certain specified conditions. Firstly, in the course of the polymerization, substantially no ~ixing must occur between polymer chains that have been initiated at di~ferent times. This condition is defined as "mix ~ree." Tubular reactors are well known and are designed to ~inimize mixing of the reactants in the direction o flow. As a result, reactant concentration will vary along the reactor length. In contrast, the reaction mixture in a continuous flow stirred tank reactor (CFSTR) is blended with the incoming feed to produce a solution of essentially uniform composition everywhere in the reactor. Consequently, the growing chains in a portion of the reaction mixture will have a variety of ages and thus a single CFS~R is not suitable for the process of this invention. However, it is well known that 3 or more stirred tanks in series with all of the catalyst fed to the first reactor can approximate the per~ormance of a tubular reactor. Accordingly, such tanks in series are considered to be in accordance with the present inven~ion.
A batch reactor is a suitable reactio~ vessel in which to c2rry out the process o this invention, preferably equipped with adequate agitation. The cata-lyst, solvent, and monomer are added to the reactor at the start of the po'ymerization. The charge of ., ~
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reactants is then left to polymerize for a time long enough to produce the desired product. For economic reasons, a tubular reactor is preferred to a batch reac-tor for carrying out the processes of this invention.
~ n addition to the i~portance of the reactor s~stem to make narrow ~'D cc=2onent copolymers the poly-merization should be conducted in 2 menner such that for each component or mode in the h~:
a. the catalyst system produces essentially one active catalyst species, b. the reaction ~i~;ture is essentially free of chain transfer egents, and c- for each mode the polymer chains are es-sentially all initiated simultaneously, which~
is at the sa~e ti~e for a batch reactor or at the same point along the length of the tube for a tubular reactor.
The desired poly~er can also be obtained if additional solvent and reactants ~e.g., at least one of the ethylene, alpha-olefin and diene) are added either along the length of a tub~lar rezctor or during the cc~rse of polymerization in a batch reactor. Operating in this f2shion can be decirable in certain cireum-stences to control the pol.~Prization r2te or pol~er cc-?osition. However, it is necessary to add the eata-l~st at the inlet or specific locetions of the tube or at the onset of or ae specific times in batch reactor operation to meet the require~ent tha~ for each mode essentially all ~olymer chains are initiated simultaneously.
Accordingly, narrou ~.1~ co~ponent copolymers are produced by carrying out a pol~erization reaction:
(a) in a least one mix free reactor, - (b) us;ng catalyst syste~s such ~hat each com-po-.ent or ~ode in the I.~ is produced by essentially one active catalyst species, (c) using at least one reaction mixture which is essentially transfer ager~-free, and ,' . ' ~ . ' .
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(d) in such a manner and under conditions suf-ficient to initiate propag2tion of essentially all poly-mer ~hains made with a p2rticular ca~alyst species siuultaneously~
To produce the mul~imodal MWD poly~er of this in~ention, these polymeriz~tion conditions are used to generate each of the narro~ ~WD modes that comprise the final polymer product. A number of techniques are availablP for achieving this: ~
1) In a single mux free reactor operated as described above, portions o. the polymer product can be ~i.hdrawn after varying ti~es in a batch reactor or at rying distances along a tubular reactor representing ci rPrent average molecular weights and these portions cc~ be blended. -2) Mix free reactors can be operated either in~e-allel or sequentially and ~he products blended.

3) Two or more cetalysts that form narrow MWD
pcl}~er of difrering molecular weight can be added at the onset of polymerization in a mixfree reactor. Each ca~21yst must meet the requirements of minimizing chain trcnsfer and initiating sir~ltaneous propagation of 211 the chains produced by that catalyst.

4) A catalys~ system that generates mul~iple ~c;ive catalyst species can be added at the start of the poly~erization. Each cat21yst species produced must gi~e simult2neous ch~in initiation and mini~ize chain transfer .

5) Add;tional catalyst and monomer, if desired, can be added at varying lengt~s along a tubular reector o~ times in a batch reactor to initiate the for-~aLion of additional M~.~ ~odes. The catalysts can ~e the same or different, as long as chains are initiated si-ultaneously and chain tr2nsfer is minimized.

6~ For c talyst system that show a decay i~
activity as a function of ~i~e due to deac~ivation, ca~
alys~ reactivator can be added during the course of the :. . :, . . -- . ' -.

~7~

polymerizatiGn to regenerate the dead catalyst and form a new mode o~ narrow ~.~ copolymer~
Catalyst reactivators are well known in the ar~ for increasing the productivity of vanadium Ziegler ca~alysts. These materials rejuvenate catalyst sites ~hat have become inert due to termination reactions and thereby cause reinitiation of polymer chain growth.
~en added to a reactor operating according to the pro-cess of this invention, catalyst reactivators have an ef~ect similar to that of ad~ing a second catalyst feed.
~any reactivators are known, and examples of suitable materials can be found in U.S. Patents 3,622,548, 3,629,212, 3,723,348, 4,168,358, 4,181,790 and 4,361,686. Esters of chlorinated organic acids are pre-ferred reactivators for use with the vanadium catalyst systems of t~is invention. Especially preferred is buLyl perchlorocrotanate.
In ~he processes of this invention that uti-lize multiple catalysts or multiple catalyst additions during the course of polymerization the mix free condi-tion of the reactor refers to the polymer chains of each individual mode of the MWD and not to the polymer as a whole.
A preferred multiple catalyst system comprises t'C14 combined with VOCl3 and an alkyl aluminum sesqui-~alide as a cocatalyst. The resultant polymer is a bi~odal M~ polymer.
Since the present invention is considered to be most preferred in the context of ethylene-propylene (EPM) or ethylene-propylene-diene (EPDM) copolymers, it will be d~scribed in detail in the context of EPM and/or EPDM.
Copolymer in accordance with the present in-veneion is preferably made in a tubular reactor. When produced in a tubular reactor with monomer feed only at the tube inlet, it is known that at the beginn~ng o the ~u~ular reactor ethylene, due to its high reacti~ity, .

. . .
.. ' -l will be pr~ferentially polymerized. However, the con-centration of monomers changes along the tube in favor of propylene as the ethyl~ne is depleted. The result i5 copolymer chains which are higher in ethylene concen-tration in the chain segments grown near the reactor in-let (as defined at the point at which the polymerization reaction commences), and higher in propylene concen-tration in the chain segments formed near ~he reactor outlet. An illustrative copolymer chain of ethylene-pr¢pylene is schematically presented below the E repre-senting ethylene constituents and P representing propylene constituents in the chain:

S gment E-E-E-E-P-E-E-E-P-P-E-E-P-P-P-E-P-P-P-P
As can be seen from this illustrativP schemat-ic chain, the far left-hand segment (1) thereof repre-sents that portion of the chain formed at the reactor inlet where the reaction mixture is proportionately richer in the more reactive constituent ethylene. This segment comprises four ethylene molecules and one propy-lene molecule. However, as subsequent segments are ~ormed from left to right with the more reactive ethy-lene baing depleted and the reaction mixture proportion-ately increasing in propylene concentration, the subse-quent chain segments become more concentrated in propylene. The resulting chain is intramolecularly het-erogeneous .
In the event that more than two monomers are used, e.g., in the production of EPDM using a diene ter-monomer, for purposes of describing the present in~en-tion all prop~rties related to homogeneity and hetero~
geneity will refer to the relative ratio of ethylene to the o~her monomers in the chain~ ,The property, of the copolymer discussed herein, related to intramolecular compositional dispe~sity (compositional variation within a chain) shall be referred to as Intra-CD, and that re'ated to intermolecular compositional dispersi~y .
- . .
.

7~

(compositional variation between chains) shall be re ferred to as Inter~CD.
For copolymers in accordance with the present in~ention, composition can vary between chains as well 2S along the length of the chain. In one embodiment of ~his invention, the Inter-CD can be characterized by the difference in composition between some raction o~ the copolymer and the average composition, as well as by the total difference in composition between the copolymer rrections containing the highest and lowest quantity of ethylene. Techniques for measuring the breadth of ~he In~er-CD are known as illustrated by Junghanns, et al., wherein a p-xylene-dimethylformamide solvent/non solvent ~as used to fractionate copolymer into fractions of dif-ering intermolecular co~position. Other solvent/non-solvent systems can be used9 sucb as hexane-2-propanol, as will be discussed in more detail below.
In one embodiment of this invention, the-Inter-CD of the individual component copolymers in ac-cordance with the present invention is such that 95 wt%
of the copolymer chains have an ethylene composition thet differs from the average component weight per~ent ethylene composition by 15 wt% or less. The preferred Inter-CD is about 13% or less, with the most preferred being about 10% or less. In comparison, Junghanns, et al., found that their tubular reactor copolymer had an Inter-CD of greater than 15 wt%. Broadly, in one embod-i~ent of this invention, the Intra-CD of copoly~er in accordance with the present invention is such that at least two portions o~ an individual component intramo-lecularly heterogeneous chain, each portion comprising at least 5 wt~ of the chain, differ in composition from one another by at least 5 wt~ ethylene. Unless other-wise indicated, this property of Intra-CD as referred to he~ein is based upon at least two 5 wt~ portions of copolymer chain. The Intra-CD of copolymer in accor-dance with the present lnvention can be such that at ~, . : . . -.
.
.

, - : :
. - ~, ,~,, , least two portions of copolymer chain differ by at least 10 wt% ~thylene. Differences of at least 20 wt%, as ~ell as of at least 40 wt% ethylene are also considered to be in accordance with the present inventionO
The experimental procedure for determining Intra-CD is as follows. First, the Inter-CD is estab-lished as described below, then the polymer chain is broken into fragments along its contour and the Inter-CD
of the fragments is determined. The difference in the ~o results is due to Intra-CD as can be seen in the il-lustrative example below.
Consider a heterogeneous sample polymer con-taining 30 monomer units. It consists of 3 molecules designated A, B, C.
A EEEEPEEEPEEEPPEEPPEPPPEPPPPPPP
B EEEEEPEEEPEEEPPEEEPPPEPPPEEPPP
C EEPEEEPEEEPEEEPEEEPPEEPPPEEPPP
~ Iolecule A is 36.8 wtZ et~ylene, B is 46.6%, and C is 50% ethylene. The average ethylene content for the mixture is 44.3Z. For ~his sample the Inter-CD is sucb that the highest ethylene polymer contains 5.7%
more ethylene than the average while the lowest ethylene content polymer contains 7.5~ less ethylene than the av-er~ge. Or, in other words, 100 wt~ of the polymer is within ~5.7% and -7.5Z ethylene about an average of 44.3%. Accordingly, the Inter-CD is 7.5~ when the given wtZ of the polymer is 100%. The distribution may be represented graphically as by curve 1 in Figure 3.
If the chains are broken into fragments, there will be a new Inter-CD. For simplicity, consider first breaking only molecule A into fragments show~ by the slashes as follows:
EEEEP/EEEPE/EEPPE/EPPEP/PPEPP/PPPPP
Portions of 72.7~, 72.7%, 50%, 30.8%, 14.3Z and 02 ethvlene are obtained. If molecules B and C are simi-larly broken and the weight ~ractions of similar compo-sieion are grouped ~he new In~er-CD shown by curve 2 in .
, , , - - , . ~ .

FiOure 3 is obtained. The difference between the two curves in the figure is due to Intra-CD.
Consideration of such data, especially near the end point ranges, demonstrates that for this sample at least 5~ of the chain contour represented by the cu-mulative weight Z range (a) differs in ~omposition from anoeher sec~ion by at least 152 ethylene shown as (b), ~he difference between the two curves. Th~ difference is composition represented by (b) cannot be intermolecu-lar. If it were, the separation process for the origi-nal polymer would have revealed the higher ethylene con-ten~s seen only for the degrad~d chain.
The compositional differences shown by (b~ and (d) in the igure between original and frag~ented chain~
give minimum values for Intra-CD. The Intra-CD must be at least that great, for chain sections have been isolated which are the given difference in composi~ion (b) or (d) from the highefit or lowest composition polymer isolated from the original. We know in this ex-ample that the original polymer represented at (b) had sections of 72.7% ethylene and OZ ethylene in the same chcin. It is highly likely that due to the inefficiency of the ~ractionation process any real polymer with In,ra-CD examined will have sections of lower or higher ethylene connected along its contour than that shown by the end points of the fractionation of the original polymer. Thus, this procedure determines a lower bound for Intra-CD. To enhance the detection, the original whole polymer can be fractionated (e.g., separate mole-cu'e A from molecule B from molecule C in the hypothet-ic21 example) with these fractions refractionated until ~hey show no (or less) Inter-CD. Subsequent fragmen~a~
tion of this intermolecularly homogeneous fraction no~
re:eals the total Intra-CD. In principle, for the exam-ple, if ~olecule A were isolated, fragmented, fraction-ated and analyzed, he Intra-CD for the chain sections wc-~ld be 72.7-0% = 72.7% rather ~han 72.7-50% = 22.7%
.

'.................. . ~ , '~L7~

seen by fractionating the whole mixture of molecules A, B and C.
In order to determine the fraction of a polymer which is intramolecularly heterogeneous in a mixture of polymers combined from several sources or as several modes in the case described here, the mixture must be separated into fractions which show no further he~erogenity upon subsequent fractionation. These ~ractions are subsequently frac~ured and fractionated to reveal which are heterogeneous.
The fragments into which the original polymer is broken should be large enough to avoid end effects and to give a reasonable opportunity for the normal sta-tistical distribution of segments to form over a gives monomer conversion range in the polymerization. In-tervals of ca 5 wt~ of the polymer are convenient. For example, at an average polymer molecular weight of about 105, fragments of ca 5000 molecular weight are appropri-ate. A detailed mathematical analysis of plug flow or ba~ch polymerization indicates that the rate of change of composition along the polymer chain ~ontour will be most severe at high ethylene conversions near the end of the polymeri~ation. The shortest fragments are needed here to show the low propylene content sections.
The best available technique for determination of compositional dispersity for non-polar polymers is solvent/non-solvent fractionation which is based on the thermodynamics of phase separation. This technique is described in "Polymer Fractionation," M. Cantow editor9 Academic 1967, p. 341 ff and in H. Inagaki, T. Tanaku, DeYelopments in Pol~mer Characterization, 3, 1 (1982).
.
For non-crystalline copolymers o ethylenP and propylene, molecular weight governs insolubility more than does compo~i~ion in a solvent/non solvent solution.
High molecular weight polymer is less soluble in a given solven~ mix. A~so, ehere is a systema-ic correlation of , : ~ , ': .
.

molecular weight with ethylene eonten~ for the poly~ers described herein. Since ethylene polymerizes much more rapidly than propylene, high ethylene polymer also tends to be high in molecular weight. Additionally, chains rich in ethylene tend to be less soluble in hydrocar-bon/polar non-solvent mixtures than propylene-rich chains. Thus the high molecular ~eight, high ethylene chains are easily separated on the basis of thermodynam-ics .
A fractionation procedure is as follows: Un-fragmented polymer is dissolved in n-hexane at 23C to form ca a lZ solution (1 g polymer/100 cc hexane).
Isopropyl alcohol is titrated into the solution until turbidity appears at which time the precipitate is al-lowed to settle. The supernatant liquid is removed and the precipitate is dried by pressing between Mylar (polyethylene terphthalate) film at 150C. Ethylene content is determined by ASI~I method D-3900. Titration is resumed and subsequent fractions are recovered an an-alyzed until lOOZ of the polymer is collected. The titrations are ideally controlled to produce fractions of S-lOZ by weight of the original polymer especially at the extremes of composition.
To demonstrate the bread-h of the distribu-tion, the data are plotted as % ethylene versus the cu-mulative weight of polymer as defined by the sum of half the weight Z of the frac~ion of ~hat composition plus the total weight % of the previously collected frac-tions.
Another portion of the original polymer is broken into fragments. A suitable ~ethod for doing this is by thermal degradation-according to the following procedure: I~ a sealed container in a nitrogen-purged oven, a 2 mm thiek layer of the poly3er is heated for 60 minutes at 330C. This should be adequate to reduce a 105 molecular weight polymer to frag~ents of ca 5000 mo-lecular weight. Such degradation does not change the . -.

: -average ethylene content o the pslymer. This polymer is fractionated by the same procedure as the high molec-ular weight precursor. Ethylene content is measured~ as well as molecular weight on selected ~ractions.
Ethylene content is measured by ASTM-D3900 for ethylene-propylene-copolymers between 35 and 85 wt%
ethylene. Above 85Z ASTM-D2238 can be used to obtain methyl group concentrations which are related to percent ethylene in an unambiguous manner for ethylene-propylene copolymers. When comonomers other than propylene are employed no ASTM tests covering a wide range of ethylene contents are available, however, proton and carbon 13 nuclear magnetic resonance czn be employed to determine the composition of such polymers. These are absolut~
techniques requiring no calibra~ion when operated such ~hat all nucleii contribute equally to the spectra. For ranges not covered by the AS~ tests for ethylene-propy-lene copolymers, these nuclear magnetic resonance meth-ods can also be used.
Molecular weight and molecular weight distri-bution are measured using a Waters 150 gel permeation chromatograph equipped with a Chromatix ~MX-6 on-line li~ht scattering photometer. The system is used at 135C with 1,2,4, trichlorobenzene as mobile phase.
Showdex (Showa-Denko America, Inc.) polystyrene gel col-umns 802, 803, 804 and 805 are used. This technique is discussed in "Liquid Chromatography of Polymers and Related ~aterials III," J. Cazes editor. Marcel Dekker, 1981, p. 207. No corrections for column spreading are employed; however, data on generally accepted standards, e.g., National Bu-reau of Standards Polyethene 1484 and anionically produced -hydrogenated polyisoprenes (an alternating ethylene-propylene copolymer) demonstrate tha~ such cor-rections on ~ /Mn or Mz/ ~ are less than .05 unit.
n is calcula~ed from an elu~ion time-molecular ~eight relationship wh~reas Mz/ ~ is evaluated using the , .
.
- . -~- :

.

li~ht scâttering photometer~ ~he numerical analyses can be performed using the co~eroially available co~puter softwear GPC2, ~OL~7T2 availzble form LDC/2~ilton Roy-R-viera Beach, ~lorida.
Since the tubular reactor is the preferred re-ac~or system for carrying out processes in accordance ~-ith the present in~ention, the follo~ing illustrative descrip~ions and exaDples are drcwn to that system, but ~ill apply to other reactor s~stems 2S will readily oc-c~r to those skilled in the art having ~he benefit of t~.e present disclosure.
In practicing processes in accordance wit~ the p-~sent invention, use is preferably made of at le2st c~e tubular reactor. Thus, in its simplest for~, such-~a p~ocess would make use of ~.ut a single reactor. Howev-er, Dore thaR one re2ctor ccn be used, either in paral-l~l,or in series with multiple monomer feeds.

For example, various structures can be pre-pared by adding additional ~onomer(s) during the course of the poly~eriz2tion, 2S shown in Fig. 4, ~-herein com-pcsltion is pl~tted versus position along the contour l~gth of a polym~r chain. The structure show~ in curve 1 is obtair.ed by ree~ing all of the ~ono2~ers to the tu-b~!cr reactor inlet or at the start of a b~tch reaction.
Ir. comparison, the structure depicted in curve 2 can be ~e by adding additional ethylene at a point along the tL~e or at a time in a batch reactor, where the cha;ns hcve reached about half their len~t~. Curve 3 requires iple. feed additions. The structure depicted by ct:rve 4 caTl be forhed if additional comonomer rather t~.en ethylene is added. This structure permits a whole et.ylen~ composition range to be omitted from the chain.
In each c2se, a third or more comonomers ~ay be added.
The co~position of the catalyst used to pro-duce alp~2-olefin copoly~ers has a pro'ound effec~ on cc?olymer product pro~er~ies such as co~positional " ' ~ .. ' , .
, ~ ~ 7 d dispersity and M~. The catalyst utilized in practicing processes in accordance wi~h the present invention should be such as to yield a controlled number of active species, each of which must be capable of simultaneous initiation of chains and must minimize chain transfer.
Each active catalyst species generated either by multi-ple catalyst feeds or by a single catalyst feed that generates multiple active species must prod~ce copolymer product in accordance with the present invention, e.g., a copolymer of narrow MWD. - The extent to which a cata-lyst species contributes to the polymeriza~ion can be readily determined using the below described techniques f~r characterizing catalyst according to the number of active catalyst species.
Techniques for characterizing catalyst accord-ing to the number of active catalyst species are within the skill of the art, as evidenced by an article enti-tled "Ethylene-Propylene Copolymers. Reactivity Ratio, E~aluation and Significance," C. Cozewith and G. Ver Str~te, Macromole~ules, 4, 482 (1971).

It is disclosed by the authors that copolymers made in a continuous flow stirred reactor (CFSTR) should have an ~D characterized by MW/Mn=2 and a narrow inter-molecular compositional distribution when one active catalyst species is present. By a combination of frac-tionation and gel permeation chromatography (GPC) it is shown that for single active species catalysts the com-positions of the fractions Yary no more than ~3Z about the average and the MWD (weight to number average ratio) or these-samples approaches two (2). It is this latter cbaracteristic (MW/~In OL about 2) that is deemed the more important in identifying a single active catalyst species. On the other hand, other catalysts gave copolymer wi~h an compositional variation greater than ~10% about the average and multi-modal ~ often wit~

.

: .
- . . ', :, . ~ ' .

M~/Mn greater than 10. These other catalysts are deemed to have more than one active species.
Catalyst syste~s to be used in carrying out processes in accordance with the present invention may be Ziegler catalysts, which ~ay typically include compo-Re~.tS selected from:
(a) a compound of a transition ~etal, i;e., a ~metal of ~roups I-B, III-B, IVB, ~'B, VI8, VIIB and VIII
of the Periodic Table, and (b) an organo~etal compound o~ a metal o~ Groups I-A, II-A, II-B cnd III-A of the P~riodic Table.
Tne preLerred catalyst syste~ in practicing pr~cesses in accordance with the present invention com-pr~'ses hydrocarbon-soluble ~anadium compound in which t~e vanadium valence is 3 to 5 and organo-alumin~w~ com-pc:nd, with the provision that the catalyst system y_elds one active catalyst species which has the ca-p~ility to produce ~arrow ~'~'D copolymers as described 2~ve. At least one of the vanadium co~pound/organo-~luminum pair selected must also contain a ~alence-bc~ded halogen.
In terms of for~ulas, vcncdi~m compounds use-f~l in practicing processes in accordance with the pre-`s~t invention could be:
(I) voclx(OR)3 x where x = 0-3 and R = a hydrocarbon radical, (II) VC14;

(III) VO(AcAc)2.
where AcAc = acetyl acetonate;

(IV) V(AcAc)3;

(V) V~)clx~AcAc)3-x~
where x ~ 1 or ~; Gnd . . . .
- . . , ,: .
, ~ . , . .

.

~7~

(VI 3 VC13 . nB, Where n - 2-3 and B ~ Lewis base capable of making hydrocarbon-soluble cQa:plexes with VC13, such as te~rahydrofuran, 2-methyl-tetrahydrofuran and dimethyl pyridine.
In formula I abQve, R preferably represents a Cl to C10 aliphatic, alicyclic or aro~atic hydrocarbon radical such as ethyl (Et), phenyl, isopropyl, butyl, propyl, n-butyl, i-butyl, t-butyl, hexyl, cyclohexyl, octyl, naphthyl, etc. Non-limiting, illustrative exam-ples o~ formula (1) and (2) compounds are vanadyl tri-halides, alkoxy halides and alkoxides such as VOC13, VOC12(0Bu) where Bu = butyl7 and VO(OC2H5~3. The most preferred vanadium compounds are VC14, VOC13, and VGC12(OR).
As already noted, the co-catalyst is pref-erably organo-aluminum compound. In terms of chemical formulas, these compounds could be as follows:
AlR3. AltOR')R~.
AlR2Cl, R2Al-O-AlR'2, AlR'RCl AlR2I;

AlRC12 .
and mixtures thereof where R and R' represent hydro-~arbon r~dicals, the same or different, as described above with respect to the vanadium compound formula.
The most preferred organo-aluminum compound is an alumi nu~ alkyl sesquichloride such as A12Et3C13 or A12(iBu~3-C13. In one embodiment of the invention the aluminum coapound can be described by the formula AlRnX3 n ~here R is as ~reviously defined, X is halogen, preferably chlorine and n can vary from 1 to 2.
When catalysts are desired that produce a sin-gle 2ctive species, catalysts comprised of VOCl~ or VC14 with A12R2C13~ preferably where R is ethyl, have beeR
shcwn to be particularly effective. For best catalys~
performance, the molar amounts of catal~st components ., ~

..
- , . , ~
` ~` -` ' ' ,' . '-, .
`' - .: :

~30-~ddPd to the reac~ion mixture should provide a molar ra-tio of aluminum/vanadium (AltV) of at least about 2.
The preferred minimum Al/V is about 4. The maximum Al/V
is based`primarily on the considerations of catalyst ex-pense and the desire to minimize the amount of chain transfer that may be caused by the organo-aluminum com-pound (as explained in detail below). Since, as is known certain organo-aluminum compounds act as chain transfer agents, if too much is present in the reaetion mixture the ~ /kln of the copolymer may rise above 2~
Based o~ these considerations, the maximum Al/V can be about 25, however, a maximum of about 17 is more pre-ferred. The most preferred maximum is about 15.
Chain transfer agents for the Ziegler-catalyz-ed poly~erization of alpha-olefins are well known and are illustrated, by way of example, by hydrogen or diethyl zinc for ~he production of EPM and EPDM. Such agents are very commonly used to control the molecular we~ght o~ EPM and EPDM produced in continuous flow stirred reactors. For the essentially single active species Ziegler catalyst systems used in accordance with the present invention, addition of chain transfer agents to a CFSTR reduces the polymer molecular weight but does not a~ect the molecular weight distribution. On t~e other hand~ chain transfer reactions during tubular re-actor polymerization in accordance with the present in-vention broaden polymer molecular weight distribution.
Thus ~he presence of chain transfer agents in - the re-action mixture should be minimi2ed or omitted altogeth-er. Although difficult to generalize for all possible reactions,- the amount of chain transfer agent used should be limited to those amounts that provide copoly-mer produet in accordance with the desired limits as re-gards ~D and composi~ional dispersity. It is believed tha~ the ma~imum amount of chain transfer agent present ir. the reaction mixture could be as high as about O . 2 mol~mol o~ transit;on metal , e . g., vanadium, again .. . . . .

~ .
.

' ':
. ~ , .

7~

pro~ided that the resul~ing copolyuer product is in ac cordance with the desired limits as regards M~D and com-positional dispersity. Even in the absence of added chain transer agent, chain transfer reactions can occur because propylene and organo-aluminum cocatalyst can al-so act as chain transfer agents. In general, among the organo-aluminum compounds that in combination with the vanadium compound yield just one active species, the organo-aluminum compound that gi~es the highest copoly-mer molecular weight at acceptable catalyst activity should be chosen. Furthermore, if ~he Al/V ratio has an effect on the molecular weight of copolymer product, that Al/V should b~ used which gives the highes~ molecu-lar weight also at acceptable catalyst ac~ivity. Chain transfer with propylene can best be limited by avoiding excessive temperature during the polymerization as de-scribed below.
~ Iolecular weight distribution is also broadened by catalyst deactivation during the course of the polymerization which leads to termination of growing chains. It is ~ell known that the vanadium-based Zieg-ler catalysts used in accordance with the present inven-tion are subject to such deactivation reactions ~hich depend to an extent upon the composition of the cata-lyst. Although the relationship between active catalyst lifetlme and catalyst syste~ composition is not known ~t present, for any given catalyst, deactivatiQn can be reduced by using the shortest residence ~im~ and lowest temperature in the reactor that will produce the desired monomer conversions.
~ olymerizations in accordance with the present inYentiOn should be conducted in such a manner and under condi~ions suf~icient to initiate propagation of essen-tially all copolymer chains for each par~icular catalyst species simultaneously. This can be accomplished by utilizing the process steps and conditions described be-low.

- : .
- - ~ ' . . .

7~

The ~a~aly~t com~onents are preferably pre-.ed, that i~, reacted to form active catalyst outside of the reactor, to ensure rapid chain initiation. Aging o~ the premixed catalyst system, that is D the time spent b~ the catalyst components (e.g.~ vanadium compound and o-~anoaluminum) in cont~ct ~ith one another outside of t~e reactor, must be kept within certain li~its. If not a~ed for a sufficient period of time, the com~onent~
will not have reacted ~ith each other sufficiently to yield an adequate quantity of active c2talyst species, with the result of continued catalyst species formation i~ the reactor, resulting i~ non-simultaneou.~ chain ini-~lation. Also, it is ~no-~n that the activity of the c~tGlyst speci~s will decrease with time so ~hat the ag-ing ~ust be kept below 2 mGximum limit. The minimum ag-ing period, depending on sueh ~actors 2S concentration o catalyst components, te~perature and mixing equip-m~nt, can be 2s low as abou~ 0.1 second~ The maximum a~ing period is that period of aging af ter w~ich ~he catalyst species has been de2ctivated to the point ~here it canno~ effeeti~ely be used in the polymerization pro-ce~s. In practice there is no appreciable advantage in allowing the catalyst to age longer than a time sufficient to fully react all of the available catalyst components thereby generating all of the active catalyst species which will be available for polymerization. Generally, the aging time will ordinarily be about O~l seconds to about 200 seconds or even longer, usually about 0.5 seconds ~o lO0 seconds, preferably about l second to 50 seconds. The premixing performed at low temperature such as 40C or below. I~ is preferred that the mixing be performed at 25C or below, with 15C or below being most preferred.
Where more than one catalyst is com~ined into a single catalyst feed st~eam, each catalyst and - : : ,' ' ' ' :
.
--33~

cocatalyst can be premixed separately. The several pre-mixed streams of catalysts species are then combined and fed to the reactor. Alternately, the several pre-mixed catalyst feed streams can be fed separately to different points along the reactor.
The temperature of the reaction mixture should also be kept with cer~ain limits. The temperature at ~he reactor inlet should be high enough to provide com-plete, rapid chain initiation at the start of the poly-merization reaction. The length of time the reaction mix~ure spends at high temperature must be short enought to minimize the amount of undesirable chain transfer and catalyst deactivation reactions.
Temperature control of the reaction mixture is co~plicated somewhat by the fact tha~ the polymerization reaction generates large quantities of heat. This prob-lem is, preferably, taken care of by using prechilled eed to the reactor to absorb the heat of polymeriza-tion. With this technique, the reactor is operated adiabatically and the temperature is allowed to increase duxing the course of polymerization. As an alternative to feed prechill, heat can be removed from the reaction ~ixture, for example, by a heat exchanger surrounding at least a portion of the reactor or by well-known autore-frigeration techniques in the case o~ batch reactors or multiple s~irred reactors in series.
h~ere an adiabatic reactor operation is used9 the inlet temperature of the reactor ~eed can be about -80C to about 50C. The outlet temperature of the re-action mixture can be as high as about 200C. The pre-ferred ma~imum outlet temperature is about 70C. The most preferred maximum is about 5~C. In the absence of reactor cooling, such as by a cooling jacket, to remove the heat of polymerization, the temperature of the re-action mixture will increase from reactor inlet to out-let by an amount dependent upon the heat of polymeriza-tion~ reaction mixture specific heat and the percent of -3~-copolymer in the reaction mixture (weight of copolymer per weight of solvent). For ethylene-propylene copoly-meri2ation in hexane the temp,erature rise is about 13C
per weight percent of copolymer.
Having the benefit of the above disclosure, those skilled in the art can determine the operating te~perature conditions for making copolymer in accor-dance with the present invention. For example, assume an adiabatic reactor and an outlet temperature of 35C
are desired for an ethylene-propylene reaction mixture in hexane containing 5% copolymer. The reac~ion mixture will increase in temperature by about 13C for each weight percent copolymer or 5 weight percent x 13C/wt%
= 65C. To maintain an outlet temperature of 35C, it will thus require a feed that has been prechilled to 35C-65C = -30~C. In the instance that external cool-ing is used to absorb the heat of polymerization, the feed inlet temperature could be higher with the other temperature constraints described above otherwise being applicable.
Because of heat removal and reactor tempera-ture limitat~ons, the preferred maximum copolymer con-centration at ,he reactor outlet when this is the only stream drawn from the reac~or is 25 wt/100 wt diluent.
The ~ost preferred maximum concentration is 15 wt/100 wt. When multiple streams o reaction mixture are wit~-drawn from the reactor and each part of the reaction mlxture withdrawn is blended with other parts of re-action mixture withdrawn, the blend so formed has a pre-ferred maximum copolymer concentration of about 25 ut./100 wt-. of diluent. The most preferred maximum is 15 wt./100 wt. diluent. In the case of either single or multiple product stream withdrawal, there is no lower li~it to concen~ration due to reactor operability, bu~
for economic reasons it,is preferred to have a copolymer concentration o at least 2 wt/100 wt. ~ost preferred is a concentration of at least 3 wt/100 ~t;
.

: .
' z~
-3~-The rate of flow of ~he reaction mixturethrough the reactor should be high enough to provide good mixing of the reactants in the rad;al direction and minimize mixing in the axial direction. Good radial mixing is beneficial to minimize radial temperature gra-dients due to the heat generated by the polymerization reaction. Radial temperature gradients will tend to broaden the molecular weight distribution of the copoly-mer since the polymerization rate is faster in the high temperature regions resulting from poor heat dissipa-tion. The artisan will recognize that achievement of ~hese objectives is difficult in the case of highly vis-cous solutions. This problem can be overcome to some extent through the use of radial mixing devices such as static mixers (e.g~, ~hese produced by the Kenics Corpo-ration).
Residence time of the reac~ion mixture in the mix-free reactor can vary over a wide range. The ~ini-~um can be as low as about 1 second. A preferred mini-~um is about 10 seconds. The most preferred minimum is about 15 seconds. The maximum can be as high as about 3600 seconds. A preferred maximum is about 1~00 sec-onds. The most preferred maximum is about 900 seconds.
~ ith reference to the accompanying drawings, particularly Fig 1, reference numeral 1 refers to a pre-mixing device for premixing the catalyst components.
For purposes of illustration, it is assumed that a copolymer of ethylene and propylene (EPM~ is to be pro-duced using as catalyst components vanadium tetrachlo-ride and ethyl aluminum sesquichloride. The polymeriza-tion is an adiabatic, solution polymerization process using hexane solvent for both the catalyst system and the reaction mixture.
The premixing device 1 comprises a temperature control bath 2, a fluid flow conduit 3 and mixing de~ice 4 te.g., a mixing tee). To mixing device 4 are fed hexane solvent, vanadium ~etr~chloride and ethyl ~J

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aluminum sesqui chloride through feed conduits 5 9 6 and 7, respectivelyO Upon being mixed in mixing device 4, the resulting catalyst mixture is caused to flow within conduit 3, optionally in the form of a coiled tubP, for a time long enough to produce the active catalyst spe~
cies at the temperature set by the temperatur~ bath.
The temperature of the bath is set to give the desired catalyst solution temperature in c~nduit 3 at the outlet of the bath.
Upon leaving the premixing device 9 the cata-lyst solution flows through conduit 8 into mixing zone 9 tc provide an intimate mixing with hPxane solvent and reactants (ethylene and propylene) which are fed through conduit 10. Any suitable mixing device can be used, such as a mechanical mixer, orifice mixer or mixing tee.
For economic reasons, the mixing tee is preferred. The residence time of the reaction mixture in mixing zone 9 is kept short enough to prevent significant polymer for-~ation therein before being fed through conduit 11 to ~ubular reactor 12. Alternatively, streams 8 and 10 can be fed directly to the inlet o reactor 12 if the flow rates are high enough to accomplish the desired level of intimate mixing. The hexane with dissolved monomers may be cooled upstream of mixing zone 9 to provide the desired feed temperature at the reactor inlet.
The tubular reactor is shown with optional feed and eake off points. Where the catalyst comprises only a single polymer species one or more take off points, 13, are used to withdraw polymer fractions at different points along the polymerization path. In or-der to maintain constant flow, additional solvent may be added to make up the volume of material withdrawn. Ad-ditional catalyst and monomer can be introduced through line, 14, or line, lS. Thc polymer withdrawn through line, 13, is combined with all other fractions withdrawn and collected with the reactor effluent for deashing and finishing.

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h~ere ~ore than one catalyst species is used, ~ultiple premixing devlce~, 1, are used. The mixed cat-21yst can be directed to mixing zone, 9, for mixing with acditional catalyst species and monomer or ~he effluen~
from the premixing de~ices can be co~bined prior to the ~ixing zone .
~ .~ere a mixeure of VC14 and TOC13 is used as the catalyst species in conjunction with,ethylaluminum sesquichloride (EASC), the molar retio of VC14/VOC13 can be about 0. 01 to about 100, more preferebly about 0.1 to ab~ut lQ, most preferably ebout 0.5 to about 5. The a~unt of ~he total polymer and the molecular weight of ecsh componene will be determined by the ratio and ~he feed locations and take off points 210ng the reactor.
The molar ratio of alkyl aluminum sesquihalide ~o vanadium components (VC14 plus VOC13) can be about 1 to about 40, preferably about 2 to about 40, more pref-erably about 4 to about 20, ~ost preferably about 4 to.
~bout 10, e.g., about 5 to about 10. The alkyl group of the sesquihalide is preferably a Cl-C6 alkyl group, preferably ethyl. The halide can be bromine, chlorine or iodine, preferably chlorine. The preferred aluminum eo-catalyst is ethylaluminum sesquichloride (EASC). In ~h~s system the ~wo indepenGent, non-interacting, mu-~- 211y compatible catalyst syste~s are VC14/EASC and VOC13/EASC.
In a preferred embodi~ent~ a Lewis base moder-~tor is incorporated into the catalyst system. The ~olar ratio of base to vanadium can be about 0 to about 5/1, preferably about 0 . 5/1 to about 2~1, more pref-erably abeut 1/1 to about 1.5l1. Illustrative, non-limiting examples of ~ewis bases suitable for use in the pr2ctice of this invention are NH3 ~ phenol, cyclohexa~
no-.e . tetrahydrofuran, acetyl2cetone, ethyl silicate and ~r~-n-butyl-phosphate. The Le~is base suppresses some long chain branching reactions when EPDM terpolymers are prepared.
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The polymer derî~ed from the process of this invention is deashed aad finished using conventional methods. Where t~e polymodal l~h~ is achieved by with-drawing product and different points or times from the reactor, the polymer streams are preferably blended and a single deashing and finishing process used. The re-sul~ is a thoroughly mi~ed, homogeneous polymer blend.
Alternately, each process stream can be finished inde-pendently and combined by mechan-cal mixing.
Having ~hus described the above illus~ra~ive reactor system, it will readily occur to the ar~isan that many variations can be made within the scope of the p.esent invention. For example, the placement and num-ber of multiple feed sites, the choice or temperature profile during polymerization and the concentrations or reactants can be varied to suit the end-use application.
By practicing processes in aecordance with the present învention, ethylene~alpha-olefin copolymers hav-ing polymodal MWD with each molecular weight fraction having very narrow MWD can be made by direct polymeri-zation. Although narrow MWD copolymers can be made us-ing other known techniques, such as by fractionation or mechanical degradation, these techniques are considered to be impractical to the extent of being unsuitable for co3mercial-scale operation. With respect to ~PDM made in accordance with the present invention, the products have enhanced cure properties at a given Mooney Viscosi-ty.
Where the polymodal molecular weight distribu-tion is achieved by withdrawing polymer fractions from the react~r, it will be evident from reference to this disclosure that it is critical when or where polymer is withdrawn from the reaction zone. This can be deter-mi~ed without undue experimentation. For example, a pi-lot plan~ scale tubula~ reactor can be ~quipped with a ~ultiplicity of t~ke off points. By running the reactor and withdrawing polymer sa~ples from ~he system, ., , . . -.

- -molecular weight of the polymer at poin-ts along the re-actor can be determined.
~ y converting the distance along the -tube to time of reaction after introduction of catalyst, a plot can be made of molecular weigh-t as a function of re-action time for a given catalyst/monomer/solvent system~
The molecular weight/reaction time plot can be used to position take off points. For flexibility in selecting the product characteristics of a particular polymodal MWD product, a multiplicity of take off points can be installed, not all of which will be used in preparing a particular product with predetermined specifications.
Similarly, inlet ports can be located at dif-ferent locations for the in~roduction of additional monomer or catalyst streams. By introducing fresh catalyst and monomer downstream of the inlet, the MWD of the polymer will be modified. So long as the polymer-ization is carried~out in this manner the polymer will be a polymodal MWD polymer of narrow MWD modes. Similar results are achieved by introducing fresh premixed catalyst with the additional monomer feed.
It will be evident from this disclosure to those skilled in the art that the polymodal MWD polymers of this invention can be prepared by blending the prod-uct of runs prepared under different conditions or using different catalyst. For example, one polymerization can be conducted using VC14/E~SC as the catalyst and another conducted using VOC13/EASC as the catalyst. The product of the two runs can then be blended to form a bimodal MWD polymer blend. Other variations can be used to gen-erate polymer species of different Mw to prepare poly-modal MWD compositions.
The advantages of the instant invention may be more readily appreciated by reference to the following examples.

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~l~7~8 Examp le This example illustrates the method of this in~ention for preparing an EPM wherein polymer product is removed from the reactor at a point intermediate be-tween the reactor inlet and outlet. The polymerization was conducted in a 3/8 in. diameter tube and the resi-dence time in the reactor was 30 seconds. A take off port was located downstream of the inlet at a distance equivalent to 1 second residence time.
Hexane was used as the solvent 9 VC14 as the catalyst, and A12Et3C13 as the cocatalyst. Hexane is purified prior to use by passing over 4A molecular sieves (Union Carbide, Linde Div. 4A 1/16" pellets) and silica gel (W. R. Grace Co., Davidson Chemical Div., PA-400 20-4 mesh) to remove polar impurities whic~ act as ca~alyst poisons. Gaseous, ethylene and propylene is passed over hot (270C~ CuO (Harshaw Chemical Co., COl900 ~" spheres) to remove oxygen followed by molecu-lar sieve treatment for water removal and then combined wi~ hexane upstream of the reactor and passed through a chiller which provided a low enough temperature to com-pletely dissolve the monomers in the hexane.
A catalyst solution is prepared by dissolving 18.5 ~ of vanadium tetrachloride, VC14, in 5.0 1. of pu-rified n-hexane. The cocatalyst consists of 142 g of ethylaluminum sesquichloride, A12Et3C13, in 5.O 1. of pùrified hexane. The two solutions are premixed at 10C
and aged for 8 seconds. Typical f ed rates and reacting conditions are shown in Table I.

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T~sLE I
Reactor Inlet Temperature ( C) -10 Reactor Outlet Temperature ( C) o Reactor Eeed Ra-tes Hexane (~g/hr) 60.3 Ethylene (kg/hr) 0.22 Propylene (kg/hr) 2.0 VC14 (g/hr) 2.22 A12Et3C13 (g/hr) 17 Catalyst Premixing Temperature (C) 10 Catalyst Premixing Time (sec) 8 Total Reactor Residence Time (sec) 30 A product stream is withdrawn from the take off port at about 17 kg/hr and blended with effluent from the reactor outlet. Approximately 20 wt% of the polymer in the effluent came from the take off port.
The molec~Lar weight of the product from the take off port is about one-half of that from the reactor outlet with a similar MWD (MW/Mn) = 1.4, Mz/Mw = 1.3). The product is deashed and stripped. The resulting polymer is a bimodal MWD EPM with a theoretical ~ /Mn = 1.96 and ,IZ/MW = 1. 46 .

E~ample II
Example I is repeated except that no effluent is taken from the take off port and two reactors in par-allel are used. The feed rates listed in Table 1 are split so that 17 kg./hr are passed through the reactor with one second residence time, and the remaininy feed goes to the other reactor. The residence times in these two reactors are 1 and 30 seconds, respectively. Otherwise all conditions are the same as in Example 1. The effluents from the reactor outlets are blended. After steady state is achieved, the blend is deashed, washed and stripped of solvent. The resulting polymer is a bimodal MWD EPM with a theoretical MWD as in Example I.

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~.~7~ b -b2-Ex~mple III
Example I i~ repeated except that no effluent is ~2ken from the take off port and VOC13/EASC is used 2S an additional catalyst~
The second cat~lyst sol~tion is prepared bg dissolving 18.5g of VOC13 in 500 lo of purified hexane.
The cocatalyst consists of 142g of A12Et3C13 in 5. 0 1.
of purified hexane. The VC14 and VOC13 ar~blended with coc~talysts in separate pre~ixing units and aged for ten seconds. The two premixed catalyst streams are then .mixed with the monomer/ hexzne stream and fed into the recctor. Reactor residence time is 50 seconds. Other-wise all conditions are the same as in Example I. After s~eady state is achieved, the reactor effluent is de-as~ed, washed and stripped of solvent. The resulting ?olymer is ea bimodal ~ EPM.

EYe--pleIV
Example I is repeated except that no effluent is t2ken from the take off port. The catalyst system used is vanadium oxytrichloride ~VOC13) and diethyl-aluminum chloride (AlEt2Cl). O~herwise 211 conditions ~re ~he sa~e as in Ex2mple I; Ihis catalyst system pro-duces at least two independent catalyst species, each of which initiates a separate ~WD mode. After steady state is achieved, the reactor effluent is deashed, washed and stripped of solvent. The resulting polymer is a poly-modal ~WD EPM.

Ex2nple V
`Example I is repe2ted except that no take offpo.t effluent is collected and the catalyst and feed streams are splitO About 2/3 of the monomer/hexane st~eam and 7~3 of the prem~'xed cztalyst are mixed an~
fed ~o the reactor inlet and the re~aining l/3 of t~e mono~er/hexane feed is mixed with t~e remaining eatalyst `` . ' ~, ' . ~."' ~ , .
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~43-Seream and fed into the re~ctor at a point midway be-t~een the reactor inlet and outlet. The EPI~ product is a poly~odal ~l~ polymer.

Ex2-ple VI
Exa~ple I is repected except that no effluent is taken fron the take off port and a ca~zlyst reactiva-t~r is used. The catalyst reactivator solution i~ pre-pared by dissolving 30.5g of butyl perchlorocrotonate i.n 3.0 l of purified hexane. This solution is fed into the reactor, at 3.6 g/hr along ~ith 50 g/hr of ethylene, at a point ~idway between the reactor inlet and outlet.
Otherwise all conditions are the same as in Example I.
~fter steady state is achieved, the effluent is deashed, washed and stripped of solvent. Ihe resulting product is a polymodal I~ EPM.

It will be appreci2ted by those skilled in ~he.
art wbo have reference to this disclosure that where rererence is made to t~e beginning of polymerization, in a contînuous process, this is intended to mean the time at ~-hich catalyst is introduced. Si~ilarly, the end of the poly~eri~ation in a tubular reactor ~ecns at the point where the polymerizationis terminated.
.~ere reference is ~ade to blends being made by co~bining product or re~ction mi~tures withdra~ rom the reactor at one or more times ~fter the start of polyme?rization with product from the "reactor outlet" or "co~pletion of poly~erization~' this langucge is intended ~o include the last product or reaction mixture with-dre~n from the reactor for the purpose of forming the blend whether or not the 12st product or reaction mix-ture is obtained fro~ the physical reactor outlet or a~
the.2ctual co~pletio~ of poly&eri7ation9 notwithstanding ~he fact that product from the actual reactor ou~let or ac;ual completion o~ poly~eri72tion is used for some p~-pose other than blending with fra~tions o~ poly~er i .harawn .

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Claims (237)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCINSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. In a polymerization process for producing copolymer from a reaction mixture comprised of catalyst and a monomer feed comprising ethylene, at least one other alpha-olefin monomer and, optionally, a non-con-jugated diene, the improvement which comprises producing a polymodal MWD copolymer by conducting the polymeriza-tion:
(a) in at least one reactor, said reactor be-ing a substantially mix free reactor;
(b) with essentially one active catalyst spe-cies;
(c) using at least one reaction mixture which is essentially transfer-agent free;
(d) in such a manner and under conditions suf-ficient to initiate propagation of essentially all copolymer chains simultaneously;
(e) withdrawing a part of the reaction mixture containing copolymer from the reactor at, at least two predetermined times after the start of polymerization; and (f) blending the polymer withdrawn at each such predetermined time;
thereby producing a polymodal MWD copolymer comprising at least two different molecular weight modes where-in each mode has a narrow MWD and at least one of two characteristics, (1) an MW/Mn of less than 2 and (2) Mz/Mw of less than 1.8.

2. The process according to claim 1 wherein the reactor comprises a tubular reactor having a multi-plicity of take off ports.

3. The process according to claim 2 wherein the polymer from said take off port and reactor outlet are blended by combining the reaction mixtures collected; and subsequently recovering the polymer from the combined reaction mixture.

4. The process according to claim 1 wherein the catalyst comprises a Ziegler catalyst.

5. The process according to claim 4 wherein the catalyst comprises a hydrocarbon-soluble vanadium compound and an organo-aluminum compound which react to form essentially one active catalyst species, at least one of the vanadium compound and organo-aluminum com-pound containing a valence-bonded halogen.

6. The process according to claim 1 wherein the temperature of the reaction mixture at the ini-tiation of polymerization is about -80°C to 50°C.

7. The process according to claim 1 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 200°C.

8. The process according to claim 4 wherein the polymerization is a solution polymerization.

9. The process according to claim 4 wherein the catalyst components are premixed.

10. The process according to claim 9 wherein the premixed catalyst components are aged for at least 0.5 seconds.

11. The process according to claim 5 wherein the mole ratio of aluminum to vanadium in the catalyst is about 2 to 25.

12. The process according to claim 1 wherein the polymerization is conducted in a solvent for the reaction mixture; each part of the reaction mixture withdrawn being blended with other parts withdrawn; the blend so formed having a copolymer concentration of about 3 to about 15% on a weight copolymer per weight of solvent basis.

13. The process according to claim 1 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 50°C.

14. The process according to claim 9 wherein the catalyst comprises components that are premixed and then aged for about 1 to 50 seconds.

15. The process according to claim 5 wherein the mole ratio of aluminum to vanadium in the catalyst is about 4 to 15.

16. The process according to claim 11 wherein the polymerization is conducted in a solvent for the re-action mixture, and wherein each part of the reaction mixture withdrawn from the reactor is blended with other parts withdrawn, and the blend so formed has a copolymer concentration of about 3% to 10% on a weight of polymer per weight of solvent basis.

17. The process according to claim 5 wherein the catalyst comprises:
(a) hydrocarbon-soluble vanadium compound se-lected from the group consisting of:

VOClx(OR)3-x, where x=0-3 and R=hydrocarbon radical;

VCl4, VO(AcAc)2.
where AcAc=acetyl acetonate V(AcAc)3, where AcAc=acetyl acetonate VOClx(AcAc)3-x, where x-1 or 2 and AcAc=acetyl acetonate, and VCl3.nB.
where n=2 to 3 and B=Lewis base capable of lorming hydrocarbon-soluble complexes with VCl3; and (b) an organo-aluminum compound selected from the group consisting of:

AlR3 AlR2Cl, A12R3CL3, AlRC12 .
AlR'RCl, Al(OR')R2, R2Al-OAlR'2, AlR2I and mixtures thereof, where R and R' are hydrocarbon radicals.

18. The process aecording to claim 5 wherein the catalyst comprises VCl4 and Al2R3Cl3 wherein R is a hydrocarbyl moiety.

19. The process according to claim 1 wherein the temperature of the reaction mixture at the comple-tion of polymerization is about 70°C.

20. The process according to claim 1 wherein the polymerization is adiabatic.

21. The proeess according to claim 1, which is continuous and is conducted in hexane solvent.

22. The process according to claim 1 wherein said polymerization is conducted in at least one tubular reactor.

23. The process according to claim 22 wherein said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha-olefin monomer and diene are fed to said tubular reactor at multiple feed sites.

24. The process according to claim 18 wherein R is ethyl.

25. The product prepared according to the process of claim 1.

26. The product according to claim 25 wherein said copolymer product is cured.

27. The product according to claim 25 wherein said copolymer product is blended with basestock lubri-cating oil.

28. The product according to claim 27 wherein said copolymer product is blended with the basestock lu-bricating oil in an amount from about .001 to 49 wt%.
ccpolymer based on oil plus copolymer.

29. A method for preparing a polymodal MWD
ethylene copolymer which comprises:.
(a) conducting the polymerization in a sub-stantially mix free reactor;
(b) using at least two catalysts, each of which initiates growth of polymer chains that attain a different average molecular weight than that initiated by the other catalyst;
(c) using at leest one reaction mixture com-prising ethylene, at least one alpha-olefin monomer and, optionally, a non-conjugated diene, said reaction mixture being essentially transfer-agent free;
(d) in such a manner and under such conditions sufficient to initiate propagation of essen-tially all copolymer chains made by a particu-lar catalyst species simulteneously;
thereby producing a polymodal MWD ethylene copolymer comprising at least two different molecular weight modes wherein each mode having a narrow MWD and at least one of two characteristics, (1) an MW/Mn of less than 2 and (2) Mz/Mw of less than 1.8.

30. The process according to claim 29 wherein the catalyst comprises a Ziegler catalyst.

31. The process according to claim 29 wherein each catalyst comprises a hydrocarbon-soluble vanadium compound and an organo-aluminum compound which react to form essentially one active catalyst species, at least one of the vanadium compound and organo aluminum com-pound containing a valence-bonded halogen.

32. The process according to claim 31 wherein each catalyst comprises:
(a) hydrocarbon-soluble vanadium compound se-lected from the group consisting of:

VOClx(OR)3-X, where x=0 to 3 and R=hydrocarbon radical;

VCl4;

VO (AcAc)2, where AcAc=acetyl acetonate;

V(AcAc)3 where AcAc=acetyl acetonate;

VOClx(AcAc)3-x where x=1 or 2 and AcAc=acetyl acetonate; and VC13.nB.
where n=2 to 3 and B=Lewis base capable of forming hydrocarbon-soluble complexes with VCl3; and (b) organo-aluminum compound selected from the group consisting of:

AlR3 AlR2Cl, Al2R3CL3, AlRC12, AlR'RCl, Al(OR')R2.
R2Al-OAlR'2.
AlR2I and mixtures thereof, where R and R' are hydrocarb~n radicals.

33. The process according to claim 32 wherein a first catalyst comprises VCl4 and Al2R3Cl3; and a sec-ond catalyst comprises VOCl3 and Al2R'3Cl3 where R and R' are the same or different hydrocarbyl moiety.

34. The process according to claim 33 wherein R and R' are ethyl.

35. The process according to claim 29 wherein the reactor is a tubular reactor.

36. The process according to claim 29 wherein the temperature of the reaction mixture at the initia-tion of polymerization is about -80°C to 50°C.

37. The process according to claim 29 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 200°C.

38. The process according to claim 32 wherein the polymerization is a solution polymerization.

39. The process according to claim 30 wherein the catalyst components are premixed.

40. The process according to claim 31 wherein the mole ratio of aluminum to vanadium in the catalyst is about 2 to 25.

41. The process according to claim 39 wherein tbe catalyst components are premixed and then aged for at least 0.5 seconds.

42. The process according to claim 38 wherein the polymerization is conducted in a solvent for the re-action mixture wherein the copolymer concentration in the reaction mixture at the completion of polymerization is about 3 to about 15% on a weight copolymer per weight of solvent basis.

43. The process according to claim 29 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 50°C.

44. The process according to claim 39 wherein the catalyst comprises components that are premixed and then aged for about 1 to 50 seconds.

45. The process according to claim 38 wherein the mole ratio of aluminum to vanadium in the catalyst îs about 4 to 15.

46. The process according to claim 45 wherein the polymerization is conducted in a solvent for the re-action mixture, and wherein the copolymer concentration in the reaction mixture at the completion of polymeriza-tion is about 3% to 10% on a weight of polymer per weight of solvent basis.

47. The process according to claim 29 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 70°C.

48. The process according to claim 29 wherein the polymerization is adiabatic.

49. The process according to claim 29 wherein the polymerization is continuous and is conducted in hexane solvent.

50. The process according to claim 49 wherein said reaction uixture further comprises diene, and wherein at least one of said ethylene, other alpha-olefin monomer and diene are fed to said tubular reactor at multiple feed sites.

51. In a polymerization process for producing copolymer from a reaction mixture comprised of catalyst and a monomer feed comprising ethylene, at least one other alpha-olefin monomer, and optionally, at least one non-conjugated diene, the improvement which comprises producing a polymodal MWD copolymer by conducting the polymerization:
(a) in at least two reaetors, said reactors each being a substantially mix free;

(b) with essentially one active catalyst spe-cies in each reactor;
(c) using at least one reaction mixture in each reactor which is escentially transfer-agent free in each reactor;
(d) in such a manner and under conditions suf-ficient to initiate propagation of essentially all copolymer chains simultaneously;
(e) blending the polymers from each re-actor; and (f) recovering the blended polymers;
thereby producing a polymodal MWD ethylene copolymer comprising at least two different molecular weight modes wherein each mode having a narrow MWD and at least one of two characteristics, (1) an Mw/Mn of less than 2 and and Mz/Mw, of less than 1.8.

52. The process according to claim 51 wherein.
the catalyst comprises a Ziegler catalyst.

53. The process according to claim 52 wherein each catalyst species comprises a hydrocarbon-soluble vanadium compound and an organo-aluminum compound which react to form essentially one active catalyst species, at least one of the vanadiun compound and organo alumi-num compound containing a valence-bonded halogen.

54. The process according to claim 53 wherein each catalyst comprises:
(a) hydrocarbon-soluble vanadium compound se-lected from the group consisting of:

VOClx(OR)3-.x, where x=0-3 and R=hydrocarbon radical;

VCl4;

VO (AcAc)2, where AcAc=acetyl acetonate V(AcAc)3.
where AcAc=acetyl acetonate VOClx(AcAc)3-x, where x=1 or 2 and AcAc=acetyl acetonate; and VCl3.nB, where n=2-3 and B=Lewis base capable of form-ing hydrocarbon-soluble complexes with VCl3;
and (b) organo-aluminum compound selected from the group consisting of:

AlR3 AlR2Cl, Al2R3CL3, AlRCl2 .
AlR'RCl, Al(OR')R2, R2Al-OAlR'2.
AlR2I and mixtures thereof where R and R' are the same or different hydrocarbyl radicals.

55. The process according to claim 53 wherein a catalyst comprising VCl4 and Al2R3Cl3 is used in a first reactor and a catalyst comprising VOCl3 and Al2R'3Cl3 is used in 2 second reactor wherein R and R' are the same or different hydrocarbyl moiety.

56. The process according to claim 55 wherein R and R' are ethyl.

57. The process according to claim 51 wherein the reactor is a tubular reactor.

58. The process according to claim 52 wherein the catalyst components are premixed.

59. The process according to claim 52 wherein the catalyst components are premixed and then aged.

60. The process according to claim 51 wherein the temperature of the reaction mixture at the initia-tion of polymerization is about -80°C to 50°C.

61. The process according to claim 51 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 200°C.

62. The process according to claim 59 wherein the catalyst components are aged for at least 0.5 sec-onds.

63. The process according to claim 52 wherein the mole ratio of aluminum to vanadium in the catalyst is about 2 to 25.

64. The process according to claim 51 wherein the polymerization is a solution polymerization.

65. The process according to claim 51 wherein the polymerization is conducted in a solvent for the re-action mixture; and wherein the copolymer concentration in the reaction mixture at the completion of polymeriza-tion in each reactor is about 3 to about 15% on a weight copolymer per weight of solvent basis.

66. The process according to claim 51 wherein the maximum outlet temperature of the reaction mixture at the completion of polymerization is about 50°C.

67. The process according to claim 59 wherein the catalyst comprises components that are premixed and then aged for about 1 to 50 seconds.

68. The process according to claim 53 wherein the mole ratio of aluminum to vanadium in the catalyst is about 4 to 15.

69. The process according to claim 68 wherein the polymerization is conducted in a solvent for the re-action mixture, and wherein the copolymer concentration in the reaction mixture at the completion of polymeriza-tion in each reactor is about 3% to 10% on a weight of polymer per weight of solvent basis.

70. The process according to claim 51 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 70°C.

71. The process according to claim 51 wherein the polymerization is adiabatic.

72. The process according to claim 51 wherein the polymerization process is continuous and is conduct-ed in hexane solvent.

73. The process according to claim 57 wherein said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha-olefin monomer and diene are fed to said tubular reactor at multiple feed sites.

74. In a polymerization process for producing copolymer from a reaction mixture comprised of catalyst and a monomer feed comprising ethylene, at least one other alpha-olefin monomer, and optionally, at least one non-conjugated diene the improvement which comprises producing a polymodal MWD copolymer by conducting the polymerization:
(a) a substantially mix free reactor;
(b) with essentially one active catalyst spe-cies wherein said catalyst species exhibits a decay in activity with respect to polymeriza-tion time;
(c) using at least one reaction mixture which is essentially transfer-agent free;
(d) in such a manner and under conditions sufficient to initiate propagation of essen-tially all copolymer chains formed from the catalyst species simultaneously;
(e) adding a catalyst reactivator to the re-action mixture after polymerization has pro-gressed for a finite time; and (f) recovering polymer at the completion of polymerization;
thereby producing a polymodal MWD ethylene copolymer comprising at least two different molecular weight modes wherein each mode having a narrow MWD and at least one of two characteristics, (1) an MW/Mn of less than 2 and and Mz/Mw of less than 1.8.

75. The process according to claim 74 wherein the catalyst comprises a Ziegler catalyst.

76. The process according to claim 75 wherein catalyst comprises a hydrocarbon-soluble vanadium com-pound and an organo-aluminum compound which react to form essentially one active catalyst species, at least one of the vanadium compound and organo aluminum com-pound containing a valence-bonded halogen.

77. The process according to claim 76 wherein the catalyst comprises:
(a) hydrocarbon-soluble vanadium compound se-lected from the group consisting of:

VOClx(OR)3-x, where x=0-3 and R=hydrocarbon radical;

VC14;

VO (AcAc)2, where AcAc=acetyl acetonate V(AcAc)3.
where AcAc=acetyl acetonate VOClx(AcAc)3-x, where x=1 or 2 and AcAc-acetyl acetonate; and VCl3.nB, where n=2-3 and B=Lewis base capable of form-ing hydrocarbon-soluble complexes with VCl3;
and (b) organo-aluminum compound selected from the group consisting of:

AlR3 AlR2Cl, Al2R3Cl3, AlRCl2, AlR'RCl, Al(OR')R2, R2Al-OAlR'2, AIR2I and mixtures thereof where R and R' are hydrocarbon radicals.

78. The process according to claim 76 wherein the catalyst comprises a VCl4 and Al2R3Cl3 wherein R is a hydrocarbyl moiety.

79. The process according to claim 78 wherein R is ethyl,

80. The process according to claim 74 wherein the reactor is a tubular reactor having a first inlet port and at least one additional inlet port downstream of the first inlet port, catalyst reactivator being add-ed through said additional inlet port.

81. The process cccording to claim 74 wherein the reactor is a batch reactor and the catalyst reacti-vator is added at a finite time after initiation of polymerization.

82. The process according to claim 74 wherein the temperature of the reaction mixture at the initia-tion of polymerizztion is about -80°C to 50°C.

83. The process according to claim 74 wherein ahe maximum temperature of the rection mixture at the completion of polymerization is about 200°C.

84. The process cccording to claim 74 wherein the polymerization is a solution polymerization.

85. The process according to claim 75 wherein the catalyse componenes are premixed.

86. The process according to claim 85 wherein the catalyst components are premixed and then aged.

87. The process according to claim 86 wherein the premixed catalyst components are aged for at least 0.5 seconds.

88. The process according to claim 75 wherein the mole ratio of aluminum to vanadium in the catalyst is about 2 to 25.

89. The process according to claim 74 wherein the polymerization is conducted in a solvent for the re-action mixture and wherein the copolymer concentration in the reaction mixture at the completion of polymeriza-tion is about 3 to about 15% on a weight copolymer per weight solvent basis.

90. The process according to claim 74 wherein the maximum at the completion of polymerization tempera-ture of the reaction mixture is about 50°C.

91. The process according to claim 85 wherein the catalyst comprises components that are premixed and then aged for about 1 to 50 seconds.

92. The process according to claim 85 wherein the mole ratio of aluminum to vanedium in the catalyst is about 4 to 15.

93. The process according to claim 92 wherein the polymerization is conducted in a solvent for the re-action mixture, and wherein the copolymer concentration in the reaction mixture at the completion of polymeriza-tion is about 3% to 10% of a weight of polymer per weight of solvent-basis.

94. The process according to claim 74 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 70°C.

95. The process according to claim 74 wherein the polymerization is adiabatic.

96. The process according to claim 74 which is continuous and is conducted in hexane solvent.

97. The process according to claim 74 wherein the reactor is a tubular reactor.

98. The process according to claim 97 wherein the catalyst reactivator is introduced to said tubular reactor at multiple additional inlet ports said reacti-vator being optionally introduced with additional monomer.

99. In a polymerization process for producing copolymer from a reaction mixture comprised of catalyst and a monomer feed comprising ethylene and at least one other alpha-olefin monomer, and optionally at least one non-conjugated diene, the improvement which comprises producing a polymodal MWD copolymer by conducting the polymerization:
(a) in at least one reactor, said reactor be-ing a substantially mix free reactor-;
(b) with essentially one catalyst system which generates multiple active catalyst spe-cies each catalyst species initiating the growth of polymer chains that attain a differ-ent average molecular weight than those produced by other catalyst species;
(c) using at least one reaction mixture which is essentially transfer-agent free;

(d) in such a manner and under conditions sufficient to initiate propagation of essen-tially all copolymer chains made with a par-ticular catalyst species simultaneously;
(e) recovering polymer at the completion of polymerization;
thereby producing a polymodal MWD ethylene copolymer comprising at least two different molecular weight modes wherein each mode has a narrow MWD and at least one of two characteristics, (1) an MW/Mn of less than 2 and Mz/Mw of less than 1.8.

100. The process according to claim 99 wherein the catalyst comprises a Ziegler catalyst.

101. The process according to claim 99 wherein said catalyst comprises a hydrocarbon-soluble vanadium compound and an organo-aluminum compound which react to form essentially at least two active catalyst species, at least one of the vanadium compound and organo aluminum compound containing a valence-bonded halogen.

102. The process according to claim 101 wherein the catalyst comprises:
(a) hydrocarbon-soluble vanadium compound selected from the group consisting of:

VOClx(OR)3-x, where x=0-3 and R=hydrocarbon radical;

VO (AcAc)2, where AcAc=acetyl acetonate V(AcAc)3, where AcAc=acetyl acetonate Voclx(AcAc)3-x, where x=1 or 2 and AcAc-acetyl acetonate; and VC13.nB, where n=2-3 and B=Lewis base capable of form-ing hydrocarbon-soluble complexes with VCl3, and (b) organo-aluminum compound selected from the group consisting of:

AlR3 AlR2Cl, Al2R3Cl3, AlRCl2 .
AlR'RCl, Al(OR')R2.
R2Al-OAlR'2 AlR2I and mixtures thereof, where R and R' are hydrocarbon radicals.

103. The process acccrding to claim 102 wherein the catalyst comprises VOCl3 and AlR2Cl where R
is a hydrocarbyl moeity.

104. The process according to claim 103 wherein R is ethyl.

105. The process according to claim 99 where-in the reactor is a tubular reactor.

106. The process according to claim 99 whers-in the temperature of the reaction mixture at the ini-tiation of polymerization is about -80°C to 50°C.

107. The process according to claim 99 where-in the maximum temperature of the reaction mixture at the completion of polymerizetion is about 200°C.

108. The process according to claim 99 where-in the polymerization is a solution polymerization.

109. The process according to claim 100 wherein the catalyst components are premixed.

110. The process according to claim 109 wherein the catalyst components are premixed and then aged.

111. The process according to claim 110 wherein the catalyst components are aged for about 0.5 seconds.

112. The process according to claim 101 uherein the mole ratio of aluminum to vanadium in the cctalyst îs about 2 to 25.

113. The process according to claim 108 wherein the polymerization is conducted in a solvent for the reaction mixture; and wherein the copolymer concen-tretion in ehe reaction maxture at the completion of polymerization is about 3 to 15% on a weight copolymer per weight of solvent basis.

114. The process according to claim 109 wherein the catalyst comprises components that are pre-mixed and then aged for about 1 to 50 seconds.

115. The process according to claim 109 wherein the mole ratio of aluminum to vanadium in the catalyst is about 4 to 15.

116. The process according to claim 99 where-in the polymerization is conducted in a solvent for the reaction mixture, and wherein the copolymer concentra-tion in the reaction mixture at the completion of polymerization is about 3% to 10% on a weight of polymer per weight of solvent basis.

117. The process according to claim 99 where-in the maximum temperature of the reaction mixture at the completion of polymerization-is about 70°C.

118. The process according to claim 99 where-in the polymerization is adiabatic.

119. The process according to claim 99 which is continuous and is conducted in hexane solvent.

120. The process according to claim 105 wherein said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha-olefin monomer and diene are fed to said tubular reactor at multiple feed sites.

121. In a polymerization process for produc-ing copolymer from a reaction mixture comprised of cata-lyst and a monomer feed comprising ethylene at least one other alpha-olefin monomer and optionally at least one non conjugated diene, the improvement which comprises producing a polymodal MWD copolymer by conducting the polymerization:
(a) in at least one reactor, said reactor be ing a substantially mix free reactor;
(b) using at least one reaction mixture which is essentially transfer-agent free;
(c) with at least one first catalyst in such a manner and under conditions sufficient to initiate propagation of essentially all copolymer chains simultaneously;
(d) introducing at least one additional cata-lyst feed together with additional monomer at one or more finite times after initiation of polymerization; thereby initiating additional copolymer chains wherein the propagation of essentially all such additional copolymer chains is initiated simultaneously and wherein the additional cztalyst feed is the same or different than the first catalyst;
thereby producing a polymodal MWD ethylene copolymer comprising at least two different molecular weight modes wherein each mode having a narrow MWD and at least one of two characteristics, (1) an Mw/Mn of less than 2 and and Mz/Mw of less than 1.8.

122. The process according to claim 121 wherein the catalyst comprises a Ziegler catalyst.

123. The process according to claim 120 wherein each catalyst comprises a hydrocarbon-soluble vanadium compound and an organo-aluminum compound which react to form essentially one active catalyst species, at least one of the vanadium compound and organo alumi-num compound containing a valence-bonded halogen.

124. The process according to claim 123 wherein each catalyst comprises:
(a) hydrocarbon-soluble vanadium compound se-lected from the group consisting of:

VOClX (OR)3-X, where x=0-3 and R=hydrocarbon radical;

VCl4;

VO (AcAc)2.
where AcAc=acetyl acetonate V(AcAc )3, where AcAc=acetyl acetonate VOClx(AcAc)3-x, where x=1 or 2 and AcAc-acetyl acetonate; and VCl3.nB, where n=2-3 and B=Lewis base capable of form-ing hydrocarbon-soluble complexes with VCl3;
and (b) organo-aluminum compound selected from the group consisting of:

AlR3 AlR2Cl, Al2R3Cl3, AlRCl2 .
AlR'RCl, Al(OR')R2.
R2Al-OAlR2 AlR2I and mixtures thereof, where R and R' are hydrocarbon radicals.

125. The process according to claim 124 wherein the catalyst comprises VCl4 and Al2R3Cl3 or VOCl3 and Al2R'3Cl3 wherein R and R' are the same or different hydrocarbyl moeity.

126. The process according to claim 124 wherein R and R' are ethyl.

127. The process according to claim 125 wherein the reactor is a tubular reactor having a reactor inlet and at least one sidestream inlet port downstream of the reactor inlet, additional catalyst, and optionally, additional nonomer being added through said sidestream inlet port.

128. The process according to claim 127 wherein the additional catalyst is the same catalyst species as that added at the initiation of polymeriza-tion.

129. The process according to claim 123 wherein said additional catalyst is a different catalyst species than that introduced at the initiation of poly-merization.

130. The process according to claim 121 wherein the temperature of the reaction mixture at the initiation of polymerization is about -80°C to 50°C.

131. The process according to claim 121 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 200°C.

132. The process according to claim 121 wnerein the polymerization is a solution polymerization.

133. The process according to claim 122 wherein the catalyst components are premixed.

134. The process according to claim 133 whsrein the catalyst components are premixed and then aged for at least 0.5 seconds.

135. The process according to claim 133 wherein che catalyst components are premixed then aged.

136. The process according to claim 123 wherein the mole ratio of aluminum to vanadium in the catalyst is about 2 to 25.

137. The process according to claim 132 wherein the polymerization is conducted in a solvent for the reaction mixture, and wherein the copolymer concen-tration in the reaction mixture at the completion of polymerization is about 3 to about 15% on a weight copolymer per weight of solvent basis.

138. The process according to claim 121 wherein the maximum temperature of the reaction mixture at the completion of polymerization is about 50°C.

139. The process according to claim 132 wherein the catalyst comprises components that are pre-mixed and then aged for about 1 to 50 seconds.

140. The process according to claim 133 wherein the mole ratio of aluminum to vanadium in the catalyst is about 4 to 15.

141. The process according to claim 140 wherein the polymerization is conducted in a solvent for the reaction mixture and wherein the copolymer concen-tration in the reaction mixture at the completion of polymerization is about 3 to 10% on a weight of polymer per weight of solvent basis.

142. The process according to claim 121 wherein the maximum outlet temperature of the reaction mixture at the completion of polymerization is about 70°C.

143. The process according to claim 121 wherein the polymerization is adiabatic.

144. The process according to claim 121 wherein the polymerization is a continuous process and is conducted in hexane solvent.

145. The process according to claim 121 wherein the polymerization is conducted in at least one tubular reactor.

146. The process according to claim 1 wherein the catalyst species is derived from the reaction of VCl4 and an aluminum compound of the formula Al2R3X3 wherein X is halogen and R is a hydrocarbyl radical.

147. The process according to claim 146 wherein the aluminum compound is ethyl aluminum sesquichloride.

148. The process according to claim 29 where-in one of the catalyst species is derived from the reaction of VCl4 and an aluminum compound of the formula Al2R3X3 and wherein a second catalyst species is derived from the reaction of VOCl3 with an aluminum compound of the formula Al2R3X3 wherein X is halogen and R is a hydrocarbyl radical.

149. The process according to claim 148 wherein the aluminum compound is ethyl aluminum sesquichloride.

150. The process according to claim 51 where-in the catalyst species is derived from the reaction of VCl4 and an aluminum compound of the formula Al2R3X3 wherein X is halogen and R is a hydrocarbyl radical.

151. The process according to claim 148 wherein the aluminum compound is ethyl aluminum sesquichloride.

152. The process according to claim 74 where-in the catalyst species is derived from the reaction of VCl4 and an aluminum compound of the formula Al2R3X3 wherein X is halogen and R is a hydrocarbyl radical.

153. The process according to claim 152 wherein the aluminum compound is ethyl aluminum sesqui-chloride.

154. The process according to claim 99 where-in the catalyst species is derived from the reaction of VOCl3 and an aluminum compound of the formula AlR2X
wherein X is halogen and R is a hydrocarbyl radical.

155. The process according to claim 154 wherein the aluminum compound is diethyl aluminum chloride.

156. The process according to claim 121 wherein the catalyst species is derived from the re-action of VCl4 and an aluminum compound of the formula Al2R3X3 wherein X is halogen and R is a hydrocarbyl rad-ical.

157. The process according to claim 156 wherein the aluminum compound is ethyl aluminum sesqui-chloride.

158. The product according to claim 25 where-in the polymodal polymer comprises at least two MWD
modes, the Mw of any two adjacent modes differing from cne another by at least 50% and any one mode comprising at least 10 wt% of the total polymer.

159. The product prepared according to the process of claim 29.

160. The product according to claim 159 wherein the polymodal polymer comprises at leat two MWD
modes, the Mw of any two adjacent modes differing from one another by at leat 50% and any one mode comprising at least 10 wt% of the total polymer.

161. The product prepared according to the process of claim 51.

162. The product acoording to claim 161 wherein the polymodal polymer comprises at leat two MWD
modes, the Mw of any two adjacent modes differing from one another by at leat 50% and any one mode comprising at least 10 wt% of the total polymer.

163. The product prepared according to the process of claim 74.

164. The product according to claim 163 wherein the polymodal polymer comprises at leat two MWD
modes, the Mw of any two adjacent modes differing from one another by at leat 50% and any one mode comprising at least 10 wt% of the total polymer.

165. The product prepared according to the process of claim 99.

166. The product according to claim 165 wherein the polymodal polymer comprises at leat two MWD
modes, the Mw of any two adjacent modes differing from one another by at leat 50% and any one mode comprising at least 10 wt% of the total polymer.

167. The proauct prepared according to the process of claim 121.

168. The product according to claim 167 wherein the polymodal polymer comprises at leat two MWD
modes, the Mw of any two adjacent modes differing from one another by at leat 50% and any one mode comprising at least 10 wt% of the total polymer.

169. The process according to claim 1 wherein the catalyst species is derived from the reaction of VCl4 and an aluminum compound of the formula AlRnX3-n, wherein n can vary from 1 to 2, X is halogen and R is a hydrocarbyl radical.

170. The process according to claim 31 where-in the aluminum compound has the formula AlRnX3 n ,where-in n can vary from 1 to 2, x is halogen R is a hydro-carbyl radical.

171. The process according to claim 51 where-in the catalyst species is derived from the reaction of CCl4 and an aluminum compound of the formula AlRnX3-n, wherein n can vary from 1 to 2, X is halogen and R is a hydrocarbyl radical.

172. The process according to claim 74 where-in the catalyst species is derived from the reaction of VCl4 and an aluminum compound of the formula AlRnX3-n, wherein n can vary from 1 to 2, X is halogen and R is a hycrocarbyl radical.

173. The process according to claim 99 where-in the catalyst species is derived from the reaction of VOCl3 and an aluminum compound of the formula AlRnX3-n, wherein n can vary from 1 to 2, X is halogen and R is a hydrocarbyl radical.

174. The process according to claim 121 wherein the catalyst species is derived from the re-action of VCl4 and an aluminum compound of the formula AlRnX3-n, wherein n can vary from 1 to 2, X is halogen and R is a hydrocarbyl radical.

175. The process according to claim 74 where-in the catalyst species is derived from the reaction of VCl4 and an aluminum compound of the formula AlRnX3-n, wherein n can vary from 1 to 2, X is halogen and R is a hydrocarbyl radical.

176. The product according to claim 159 wherein the copolymer is cured.

177. The product according to claim 159 wherein said copolymer product is blended with base stock lubricating oil.

178. The product according to claim 177 wherein said copolymer product is blended with the base stock lubricating oil in an amount from about 0.001 to about 49 wt%copolymer based on the oil plus copolymer.

179. The product according to claim 161 wherein the copolymer is cured.

180. The product according to claim 161 wherein said copolymer product is blended with base stock lubricating oil.

181. The product according to claim 180 wherein said copolymer product is blended with the base stock lubricating oil in an amount from about 0.001 to about 49 wt% copolymer based on the oil plus copolymer.

182. The product according to claim 163 wherein the copblymer is cured.

183. The product according to claim 163 wherein said copolymer product is blended with base stock lubricating oil.

184. The product according to claim 183 wherein said copolymer product is blended with the base stock lubricating oil in an amount from about 0.001 to about 49 wt% copolymer based on the oil plus copolymer.

185. The product according to claim 165 wherein the copolymer is cured.

186. The product according to claim 165 wherein said copolymer product is blended with base stock lubricating oil.

187. The product according to claim 186 wherein said copolymer product is blended with the base stock lubricating oil in an amount from about 0.001 to about 49 wt% copolymer based on the oil plus copolymer.

188. The product according to claim 167 wherein the copolymer is cured.

189. The product according to claim 167 wherein said copolymer product is blended with base stock lubricating oil.

190. The product according to claim 189 wherein said copolymer product is blended with the base stock lubricating oil in an amount from about 0. 001 to about 49 wt% copolymer based on the oil plus copolymer.

191. The process according to claim 9 wherein the catalyst components are premixed and then aged.

192. The process according to claim 35 where-in said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha olefin monomer and diene is fed to said tubular reactor at multiple feed sites.
.

193. The process according to claim 74 where-in said polymerization is conducted in a tubular reac-tor.

194. The process according to claim 193 wherein said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha olefin monomer and diene is fed to said tubular reactor at multiple feed sites.

195. The process according to claim 99 where-in said polymerization is conducted in at least one tu-bular reactor.

196. The process according to claim 195 wherein said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha olefin and diene is fed to said tubular reactor at mul-tiple feed sites.

197. The process according to claim 121 wherein said polymerization is conducted in at least one tubular reactor.

198. The process according to claim 197 wherein said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha olefin and diene is fed to said tubular reactor at mul-tiple feed sites.

199. The process according to claim 145 wherein said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha olefin monomer and diene are fed to said tubular reactor at multiple feed sites.

200. The process according to claim 97 where-in said reaction mixture further comprises diene, and wherein at least one of said ethylene, other alpha-olefin monomer and diene is fed to said tubular reactor at multiple feed sites.

201. The process according to claim 107 wherein the maximum temperature of the reaction mixture is 50°C.

202. A copolymer of ethylene and at least one other alpha-olefin monomer, which copolymer is a superposition of two or more copolymer modes each of which has a MWD
characterized by having at least one of the following characteristics: a Mw/Mn of less than 2 and Mz/Mw of less than 1.8.

203. The copolymer as defined by claim 202 wherein each of said copolymer modes has a MW/Mn of less than 2 and Mz/Mw of less than 1.8.

204. Tha copolymer as defined by claim 202 wherein said alpha-olefin monomer contains 3-18 carbon atoms.

205. The copolymer as defined by claim 204 wherein said alpha-olefin monomer contains 3-6 carbons.

206. The copolymer as defined by claim 204 wherein said alpha-olefin is selected from the group consisting of propylene, butene-1, pentene 1, hexene-1, heptene-1, octene-1, and dodecene-1.

207. The copolymer as defined by claim 206 wherein said alpha-olefin is propylene.

208. The copolymer as defined by claim 202 consisting essentially of ethylene and propylene.

209. The copolymer as defined by claim 202 consisting essentially of ethylene, propylene and non-conjugated diene.

210. The copolymer as defined by claim 209 wherein said non-conjugated diene is a straight chain acyclic diene.

211. The copolymer as defined by claim 210 wherein said straight chain acyclic diene is selected from the group consisting of 1,4-hexadiene and 1,6-octadiene.

212. The copolymer as defined by claim 210 wherein said non-conjugated diene is a branched chain acyclic diene.

213. The copolymer as defined by claim 212 wherein said branched chain acyclic diene is selected from the group consisting of: 5-methyl-1, 4-hexadiene; 3,7-dimethyl-1, 6-octadiene; 3,7-dimethyl-1, 7-octadiene and the mixed isomers of dihydro-myrcene.

214. The copolymer as defined by claim 209 wherein said non-conjugated diene is a single ring diene.

215. The copolymer as defined by claim 214 wherein said single ring diene is selected from the group consisting of:
1,4-cyclohexadiene; 1,5-cyclooctadiene; and 1,5-cyclododecadiene.

216. The copolymer as defined by claim 203 wherein said non-conjugated diene is a multi ring fused or bridged ring diene.

217. The copolymer as defined by claim 216 wherein said multi-ring alicyclic fused or bridged ring diene is selected from the group consisting of: tetrahydroindene;
methyltetrahydroindene; dicyclopentadiene; bi-cyclo (2,2,1) -hepta-2, 5-diene; alkenyl, alkylidene, cycloalkenyl and cycloalkylidene norbornenes such as 5-methylene-2-norbornene (MNB), 5-ethylidene-2-norbornene (ENB), 5-propylidene-2-norbornene, 5-isopropylidene-2-norbornene, 5-(4-cyclopentenyl)-2-norbornene; and 5-cyclohexylidene-2-norbornene,

218. The copolymer as defined by claim 209 wherein said non-conjugated diene is 5-ethylidene-2-norbornene.

219. The copolymer as defined by claim 209 wherein the amount of non-conjugated diene on a weight basis of said copolymer is about 0-20%.

220. The copolymer as defined by claim 219 wherein the amount of diene on a weight basis of the copolymer is about 0-15%.

221. The copolymer as defined by claim 220 wherein the amount of diene on a weight basis of the copolymer is about 0-10%.

222. The copolymer as defined by claim 202 wherein the average ethylene content of each copolymer mode is at least 10% on a weight basis.

223. The copolymer as defined by claim 222 wherein each copolymer mode comprises at least about 30% ethylena.

224. The copolymer as defined by claim 222 wherein each copolymer mode comprises less than about 90% ethylene.

225. The copolymer as defined by claim 202 wherein the weight average molecular weight of each mode is between about 2,00012,000,000.

226. The copolymer as defined by claim 225 wherein the weight average molecular weight of each mode is between about 10,000-1,000,000.

227. The copolymer as defined by claim 226 wherein the weight average molecular weight of each mode is between about 20,000-750,000.

228. The copolymer as defined by claim 202 wherein the MW/Mn ratio for the whole copolymer is about 1-50.

229. The copolymer as defined by claim 202 wherein the Mw of any two adjcent copolymer MWD modes differs, by at least 50%.

230. The copolymer as defined by claim 229 wherein each mode comprises at least 10% by weight of the total copolymer,

231. A basestock lubricating oil blended with the copolymer product according to claim 202.

232. The basestock lubricating oil as defined by claim 231 wherein said copolymer product is blended in an amount of 0.001 to about 49 weight percent copolymer based upon oil plus copolymer.

233. A cured copolymer as defined by claim 202.

234. A cured copolymer as defined by claim 209.

235. The copolymer as defined by claim 202 wherein the Intra-CD of at least one of said modes is greater than 5%.

236. The copolymer as defined by claim 235 wherein the Intra-CD of at least one of said modes is greater than 15%.

237. The copolymer as defined by claim 209 wherein the Intra-CD of at least one of said modes is greater than 5%.