Abstract: A method of producing graft block copolymers which comprises (a) grafting a halosilane of the formulaHSiX.sub.n R.sub.3-nwherein X is halogen, R is alkyl or aryl, and n=1-3, onto a .alpha.-olefin/diene copolymer made from at least one .alpha.-olefin and at least one diene, (b) anionically polymerizing at least one anionically polymerizable monomer to form living polymer chains, and (c) reacting the products of (a) and (b) together wherein the living polymer chains react with the halosilane groups on the .alpha.-olefin/diene copolymer and are added thereto as pendant side chains.

Abstract: An initiation system for the anionic polymerization of (meth)acrylic monomers and, optionally, nonacrylic vinyl monomers is disclosed. The initiation system comprises (1) a functional initiator and (2) an alkali metal alcoholate having the formula R'OM', in which M' is an alkali metal and R' is a group R.sup.1 (OR.sup.2).sub.m where R.sup.1 is a C.sub.1 -C.sub.6 alkyl or arylalkyl radical, R.sup.2 is a C.sub.2 -C.sub.4 alkylene radical and m is equal to 1, 2 or 3. The initiation system is applied to the formation of (meth)acrylic homopolymers and block copolymers of (meth)acrylic monomers and, optionally, nonacrylic vinyl comonomers.

Abstract: A diblock copolymer obtained by polymerizing acrylic, methacrylic or nonacrylic vinyl monomers in the presence of a polymerization initiating amount of an initiation system including (1) at least one functional initiator and (2) an alkali metal alcoholate. The alcoholate has the formula:R'OM'in which M' is an alkali metal and R' has the formula:R.sup.1 (OR.sup.2).sub.min which R.sup.1 is a linear or branched alkyl radical containing from 1 to 6 carbon atoms or an arylalkyl radical, R.sup.2 is a linear or branched alkylene radical containing from 2 to 4 carbon atoms, and m is the integer 1, 2 or 3.

Abstract: A multifunctional anionic polymerization initiator which is in the form of a star-shaped polymer soluble in an apolar medium and substantially free of residual double bonds. The initiator is denoted by the general formula (PA).sub.a N.sup.n- nLi.sup.+. PA is a polymer block of a vinylaromatic or diene monomer A. The variable "a" is the number of branches in the block PA. N is a crosslinked core comprising no or practically no residual double bonds and has the formula (PMc)(RLi).sub.p. Mc is a monomer containing at least two polymerizable double bonds per molecule. PMc is a crosslinked core of at least one polymerized monomer Mc, containing 3 to 30% of residual double bonds in relation to the initial double bonds originating from the monomer Mc. R is an alkyl, aryl, arylalkyl, alkylaryl, cycloalkyl, or alkenyl. The variable "p" is the number of residual double bonds in PMc which are neutralized by RLi. The variable "n" is the number of anionic sites present in the crosslinked core N.

Abstract: A process is provided for the preparation of tapered copolymers by the nonaqueous dispersion polymerization of a mixture of 30 to 70% by weight of a conjugated diolefin monomer, preferably butadiene, and 30 to 70% by weight of a vinyl substituted aromatic monomer, preferably styrene, in a liquid hydrocarbon dispersion medium with an anionic initiator catalyst system in the presence of a block copolymeric dispersing agent. At least one block of the dispersing agent is prepared prior to the dispersion polymerization reaction and at least one block of the dispersing agent is prepared in situ during the dispersion copolymerization. The block of the dispersing agent that is prepared in situ has the polymer structure of the tapered copolymer.

Abstract: A method for preparing blends of a copolymer in a polymerization process by sequentially charging: (1) an initiator and monovinylaromatic monomer in the presence of a randomizer; (2) an initiator and monovinylaromatic monomer; (3) a mixture of monovinylaromatic and conjugated diene monomers; (4) a mixture of monovinylaromatic and conjuated diene monomers; (5) conjugated diene monomer; and (6) a coupling agent; and the polymodal tapered block copolymers prepared thereby. The copolymers are particularly useful neat or in blends for applications such as packaging and food or drink containers which require transparency and good environmental stress crack resistance.

Abstract: A block copolymer comprising a polymer block of an aromatic vinyl compound, a polymer block of butadiene and a polymer block of isoprene, having a weight average molecular weight of 10,000-500,000, containing 10-50 wt. % of a bound aromatic vinyl compound, 10-60 wt. % of bound butadiene, 10-60 wt. % of bound isoprene, at most 15 wt. % of 1,2-vinyl bonds in a butadiene segment and at most 10 wt. % of 3,4-vinyl bonds in an isoprene segment, and having a storage modulus (G') of 10.sup.6 -3.times.10.sup.8 Pa in a viscoelasticity measurement in a temperature range of from 0.degree. C. to 50.degree. C. and only one peak on loss tangent (tan .delta.) attributable to the butadiene polymer block and the isoprene polymer block in a temperature range of from -80.degree. C. to -50.degree. C. scarcely undergoes a change of melt viscosity with time. A pressure sensitive adhesive composition comprising the block copolymer and a tackifier is also provided.

Abstract: There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are each a polymer (I polymer) of at least one conjugated diene I, e.g., isoprene, which contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms; at least one middle or interior block is a hydrogenated polybutadiene (B polymer); and at least one middle or interior block is an essentially straight chain polyethylene (E polymer) resulting from the hydrogenation of a polybutadiene composed of at least 80% of 1,4-units; or 2) the terminal blocks are random IB copolymers of at least one diene I as previously defined and hydrogenated butadiene, and at least one middle or interior block is a straight chain polyethylene (E polymer) as previously defined.

Abstract: Disclosed herein is a process for anionic polymerization of selected methacrylate monomers at elevated (as high as about 100.degree. C.) temperatures, while maintaining good "living" characteristics, by carrying out the polymerization in the presence of a silicon compound and a large cation. Also disclosed is an improved process for the polymerization of vinyl monomers, including methacrylates, which process comprises the use of an anionic intiator which is a combination of an alkali metal hydride and an alkoxysilane or a combination of an alkali metal alkoxide and a silicon hydride.

Abstract: Process for the preparation of an efficient industrial .alpha., .omega.-dilithio poly(conjugated diene) diinitiator having a peak molecular weight in the range of from 1000 to 3000, comprising the reaction of mono-organolithium initiator with diisopropenyl benzene in an apolar hydrocarbon solvent, optionally in the presence of a tertiary amine, followed by addition to the reaction mixture of a small amount of conjugated diene monomer and at least 15 vol % of an aromatic ether activator at a temperature in the range of from 0.degree. to 30.degree. C.; the use of said .alpha., .omega.-dithio initiator for the manufacture of symmetrical block copolymers by anionic polymerization, from monovinylaromatic, conjugated diene and/or polar vinyl compound monomers; and block copolymers so obtained having a combination of a narrow molecular weight distribution (Mw/Mn.ltoreq.1.20) and relatively low vinyl content (.ltoreq.18%).

Abstract: A graft block copolymer is comprised of a saturated olefinic backbone with pendent anionic polymer side chains. The polymer is produced by copolymerizing an .alpha.--olefin with a 1-alkenyl monomer containing a functional group to which an anionically polymerized polymer can be grafted to produce graft block copolymer, anionically polymerizing at least one anionically polymerizable monomer to form living polymer chains, and then grafting the living polymer chains onto the copolymer to form the graft block copolymer.

Abstract: A one-step polymerization process for producing a bimodal resin having a distinct low molecular weight portion and a high molecular weight portion includes initiating an anionic polymerization of a monomer or monomers to produce living polymer chains, terminating a portion of the living polymer chains, and completing the polymerization of the remaining living polymer chains. The bimodal resin is useful, for example, in high gloss, low melt toner applications.

Abstract: A method for preparing tapered block copolymers which are particularly useful for blend components in blends with polymers of styrene. In the first embodiment of this invention the copolymers are prepared in a polymerization process by sequentially charging: (1) an initiator and monovinylaromatic monomers in the presence of a randomizer; (2) an initiator and monovinylaromatic monomers; (3) a mixture of monovinylaromatic and conjugated diene monomers; and (4) a coupling agent; to produce a polymodal tapered block copolymer. In a second embodiment of the Invention tapered block copolymers are prepared in a polymerization process by sequentially charging: (1) an initiator and monovinylaromatic monomers in the presence of a randomizer; (2) an initiator and monovinylaromatic monomers; (3) a mixture of monovinylaromatic and conjugated diene monomers; (4) a mixture of monovinylaromatic and conjugated diene monomers; and (5) a coupling agent; to produce a polymodal tapered block copolymer.

Abstract: A graft block copolymer is comprised of a completely saturated olefinic backbone with pendant anionic polymer side chains. The polymer is produced by copolymerizing an .alpha.-olefin with a monomer which contains a functional group which can be metallated so an anionic monomer can be polymerized therefrom, metallating the copolymer by reaction with metal alkyl or aryl compound and a metallation activator, and growing anionic polymer side chains from the copolymer backbone by reacting an anionically polymerized monomer with the metallated copolymer.

Abstract: The invention relates to a star block copolymer of the formula [S.sub.1 -S.sub.2 -(B.sub.1 /S.sub.3)-B.sub.2 ].sub.m -X-[B.sub.2 (B.sub.1 /S.sub.3)-S.sub.2 ].sub.n in which X represents a polyfunctional radical resulting from a coupling agent, m and n represent non-zero integers such that m+n is equal to 3 or 4, S.sub.1 and S.sub.2 each represent a block of a polymer containing at least one vinylaromatic monomer, B.sub.2 represents a block of a polymer containing at least one conjugated diene, (B.sub.1 /S.sub.3) represents a block of a statistical copolymer containing at least one vinylaromatic monomer and at least one conjugated diene, 40 to 75% by weight of (B.sub.1 /S.sub.3) consisting of resulting from vinylaromatic monomer, characterized in that the sum of the mass of the blocks B.sub.2 contains more than 40% by weight and less than 90% by weight of the total mass of the conjugated diene contained in the said star block copolymer. The invention also relates to the process for obtaining this copolymer.

Abstract: There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are each a polymer (I polymer) of at least one conjugated diene I, e.g., isoprene, which contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms; at least one middle or interior block is a hydrogenated polybutadiene (B polymer); and at least one middle or interior block is an essentially straight chain polyethylene (E polymer) resulting from the hydrogenation of a polybutadiene composed of at least 80% of 1,4- units; or 2) the terminal blocks are random IB copolymers of at least one diene I as previously defined and hydrogenated butadiene, and at least one middle or interior block is a straight chain polyethylene (E polymer) as previously defined.

Abstract: There are disclosed novel comb graft polymers and copolymers comprising a backbone of a linear polymer of p-methylstyrene (p-MS) and grafted branches of a linear addition polymer of at least one anionically polymerizable compound. The polymers may be produced by metallating the p-MS polymer with an organo alkali metal metallating agent, e.g., an alkyllithium, at active hydrogen sites along the polymer chain and graft polymerizing the anionically polymerizable compound at the metallated sites to form the grafted branches. Certain of the foregoing comb graft polymers and copolymers, e.g., wherein the backbone is a homopolymer of p-MS or a copolymer of p-MS and a ring-substituted alkylstyrene such as p-tert-butylstyrene (t-BS) and the branches are a polymer of t-BS, are useful as additives to functional fluids, particularly hydrocarbon lubricating oils, for the purpose of thickening and improving their viscosity index.

Abstract: Star polymers having first polymeric arms comprising a hydrogenated conjugated diene and smaller second polymeric arms of a methacrylate resist coupling of methacrylate blocks attached to different cores and have improved performance as viscosity index improvers. The polymerized methacrylate units are converted to amide or imide groups by reaction with a primary or secondary amine to give the viscosity index improver dispersant properties.

Abstract: Novel star-branched polymers in which the arms are each a polymer of an anionically polymerizable monomer consisting of monoethylenically unsaturated compounds comprising p-tert-butylstyrene (t-BS) coupled with a polyalkenyl coupling agent. Certain of the foregoing star-branched polymers, e.g., wherein the arms are a homopolymer of t-BS and the coupling agent is divinylbenzene (DVB), are useful as additives to functional fluids, particularly hydrocarbon lubricating oils, for the purpose of improving their viscometric properties.

Abstract: The invention is a process for the preparation of a block copolymer which corresponds to the formula ABA wherein A comprises units derived from one or more monoalkenyl arenes; and B comprises units derived from one or more conjugated dienes and the residuum of a difunctional initiator; wherein the process comprises:I) contacting (a) a difunctional initiator capable of initiating the polymerization of a compound containing a double bond with (b) a portion of conjugated diene in a portion of hydrocarbon solvent under conditions such that the conjugated diene polymerizes to a degree of polymerization of 30 or greater;II) contacting with the polymerization mixture of I additional conjugated diene and hydrocarbon solvent under conditions such that the added conjugated diene polymerizes; andIII) contacting with the polymerization mixture of II a monoalkenyl arene to prepare a block copolymer having a number average molecular weight of about 31,500 to about 400,000 and an average weight percent of monoalkenyl arenes

Abstract: A viscous block copolymer of the formula(A--B--A.sub.p).sub.n --Y.sub.r --(A.sub.q --B).sub.mwherein Y is a coupling agent or coupling monomers, andwherein A and B are polymer blocks which may be homopolymer blocks of conjugated diolefin monomers, copolymer blocks of conjugated diolefin monomers or copolymer blocks of conjugated diolefin monomers and monoalkenyl aromatic hydrocarbon monomers, andwherein the A blocks have a higher number of more highly substituted aliphatic double bonds per unit of block mass than do the B blocks, andwherein the A blocks have a molecular weight from about 100 to about 3000 and the B blocks have a molecular weight from about 1000 to about 15,000, andwherein p and q are 0 or 1 and n>0, r is 0 or 1, m.gtoreq.0 and n+m ranges from 1 to 100.This block copolymer is preferably partially hydrogenated, epoxidized and crosslinked through at least some of the epoxy functionality to form an adhesive, coating or sealant composition.

Abstract: There are disclosed novel, solid, elastomeric block copolymers having excellent oxidative and thermal stability, wherein the terminal blocks are each a polymer (D polymer) of at least one conjugated diene D, which is a hydrocarbon containing a 1,3-conjugated diene structure wherein the 2 and 3 carbon atoms are each additionally bonded to a hydrocarbyl side group, e.g., 2,3-dimethyl-1,3-butadiene, with a preponderance of polymerized D units being 1,4 units; and at least one interior block is a hydrogenated polymer (I polymer) of at least one conjugated diene I which is a hydrocarbon containing a 1,3-conjugated diene structure wherein one of the 2- and 3-carbon atoms is additionally bonded to a hydrocarbyl side group and the other is additionally bonded to a hydrogen atom, e.g. isoprene.

Abstract: A method for preparing block copolymers from which can be made transparent blue articles comprising sequentially charging under polymerization conditions at least one monovinylaromatic monomer and at least one conjugated diene monomer, wherein at least the first monomer charge is a monovinylaromatic monomer charge polymerized in the presence of an initiator; wherein at least one other charge polymerized in the presence of an initiator is a monomer selected from the group of conjugated diene monomers and mixtures of monovinylaromatic and conjugated diene monomers; wherein the final monomer charge is a conjugated diene charge; and thereafter charging the reaction mixture with at least one coupling agent. The invention copolymers are particularly useful for applications such as packaging, display devices, toys and decorative items in which transparent blue appearance is desired without significant compromise of other physical and mechanical properties.

Abstract: A method for preparing resinous polymodal monovinylarene-conjugated diene block copolymers and polymers produced thereby are provided. The method comprises sequentially contacting under polymerization conditions:(a) a monovinylarene monomer and initiator;(b) initiator and a monovinylarene monomer;(c) a sequence of at least two charges selected from the group consisting of (i) initiator and a monovinylarene monomer, (ii) a mixture of monovinylarene monomer and conjugated diene monomer, (iii) a conjugated diene monomer, (iv) a monovinylarene monomer;(d) s coupling agent;wherein the sequence of at least two charges in step (c) can be made in any order. In a preferred embodiment, at least three initiator charges are provided. In another preferred embodiment, at east three monovinylarene charges precede the first charge containing conjugated diene. In another preferred embodiment, at least four monovinylarene charges precede the first charge containing conjugated diene.

Abstract: There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are each a polymer (I polymer) of at least one conjugated diene I, e.g., isoprene, which contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms; at least one middle or interior block is a hydrogenated polybutadiene (B polymer); and at least one middle or interior block is an essentially straight chain polyethylene (E polymer) resulting from the hydrogenation of a polybutadiene composed of at least 80% of 1,4- units; or 2) the terminal blocks are random IB copolymers of at least one diene I as previously defined and hydrogenated butadiene, and at least one middle or interior block is a straight chain polyethylene (E polymer) as previously defined.

Abstract: A method for preparing tapered block copolymers in a polymerization process by sequentially charging: (1) an initiator and monovinylaromatic monomer in the presence of a randomizer; (2) an initiator and monovinylaromatic monomer; (3) a mixture of monovinylaromatic and conjugated diene monomers; (4) a mixture of monovinylaromatic and conjugated diene monomers; (5) conjugated diene monomer; and (6) a coupling agent; and the polymodal tapered block copolymers prepared thereby. The copolymers are particularly useful neat or in blends for applications such as packaging and food or drink containers which require transparency and good environmental stress crack resistance.

Abstract: A viscous block copolymer of the formula(A--B--A.sub.p).sub.n --Y.sub.r --(A.sub.q --B).sub.mwherein Y is a coupling agent or coupling monomers, andwherein A and B are polymer blocks which may be homopolymer blocks of conjugated diolefin monomers, copolymer blocks of conjugated diolefin monomers or copolymer blocks of conjugated diolefin monomers and monoalkenyl aromatic hydrocarbon monomers, andwherein the A blocks have a higher number of more highly substituted aliphatic double bonds per unit of block mass than do the B blocks, andwherein the A blocks have a molecular weight from about 100 to about 3000 and the B blocks have a molecular weight from about 1000 to about 15,000, andwherein p and q are 0 or 1 and n>0, r is 0 or 1, m.gtoreq.0 and n+m ranges from 1 to 100.This block copolymer is preferably partially hydrogenated, epoxidized and crosslinked through at least some of the epoxy functionality to form an adhesive, coating or sealant composition.

Abstract: The application discloses a functionalized multiblock macromonomer of formula: ##STR1## or of formula: ##STR2## in which formulae: each of the blocks A, B and C represents a sequence of a monomer chosen from the acrylic, vinylaromatic, methacrylic, diene, vinylpyridine, vinylpyrrolidone, alkylene oxide, lactam, lactone and maleimide monomer classes, on condition that at least one of the blocks A and C is chosen from a different class to that of block B and that at least one of the blocks A, B or C is a (meth)acrylic sequence,m, n and p are integers representing the number of monomer units in the sequence under consideration, such that 3.ltoreq.n.ltoreq.1000, 0.ltoreq.m.ltoreq.1000 and 0.ltoreq.p.ltoreq.1000, on condition that m and p are not 0 at the same time, andF is a group terminated by O.sup.-, by OH, by an .alpha.,.beta.-ethylenic unsaturation, or by an oxirane groups.

Abstract: Novel metallated polyolefins are produced by contacting a polyolefin having a vinylidene group in the terminal portion with organoalkali metal compound in the presence of alkali metal t-alkoxide or tertiary amine. The metallated polyolefin is used to initiate the polymerization of polymerizable monomers to produce block copolymers of at least two blocks, at least one of which is saturated polyolefin.

Abstract: A method for improving the initiation efficiency during the anionic polymerization of 15 to 100 percent weight of a vinyl aromatic hydrocarbon monomers and 0 to 85 percent by weight of a conjugated diene monomer by conducting the polymerization in the presence of a catalytically effective amount of: (a) an organolithium initiator and (b) a 2,5-substituted tetrahydrofuran modifier having the structural formula: ##STR1## wherein R.sub.1 and R.sub.1 ' are independently H or an alkyl group containing 1 to 4 carbon atoms and R.sub.2 and R.sub.2 ' are alkyl group containing 1 to 4 carbon atoms.

Abstract: A process for preparing a coupled asymmetric block copolymer of a vinyl aromatic hydrocarbon and a conjugated diene which comprises:(a) adding sufficient anionic polymerization initiator to the vinyl aromatic hydrocarbon monomer to start polymerization of the vinyl aromatic hydrocarbon,(b) polymerizing the vinyl aromatic hydrocarbon for a time sufficient to form a first set of vinyl aromatic hydrocarbon blocks having a desired molecular weight,(c) adding sufficient anionic polymerization initiator to start polymerization of a second set of vinyl aromatic hydrocarbon blocks,(d) completing the polymerization of the vinyl aromatic hydrocarbon for a time such that the first set of vinyl aromatic hydrocarbon blocks continues to grow to the desired molecular weight and the second set of vinyl aromatic hydrocarbon blocks grows to a desired smaller molecular weight,(e) adding a conjugated diene and polymerizing it on the ends of the vinyl aromatic hydrocarbon blocks for a time sufficient to form vinyl aromatic hydroc

Abstract: There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are polymers of at least one conjugated diene I, e.g., isoprene, which contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms, at least one middle or interior block is a polymer of butadiene, and at least one middle or interior block is a polymer of at least one aryl-substituted olefin, e.g., styrene; or 2) the terminal blocks are random copolymers of at least one diene I as previously defined and butadiene, and at least one middle or interior block is a polymer of at least one aryl-substituted olefin.

Abstract: There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are each a polymer (I polymer) of at least one conjugated diene I, e.g., isoprene, which contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms; at least one middle or interior block is a hydrogenated polybutadiene (B polymer); and at least one middle or interior block is an essentially straight chain polyethylene (E polymer) resulting from the hydrogenation of a polybutadiene composed of at least 80% of 1,4-units; or 2) the terminal blocks are random IB copolymers of at least one diene I as previously defined and hydrogenated butadiene, and at least one middle or interior block is a straight chain polyethylene (E polymer) as previously defined.

Abstract: Star polymers having first polymeric arms comprising a hydrogenated conjugated diene and smaller second polymeric arms of a methacrylate resist coupling of methacrylate blocks attached to different cores and have improved performance as viscosity index improvers. The polymerized methacrylate units are converted to amide or imide groups by reaction with a primary or secondary amine to give the viscosity index improver dispersant properties.

Abstract: Polymers comprising anionically polymerized conjugated dienes or vinylarenes and adjacent units of (1-methyl-1-alkyl)alkyl esters such as t-butylmethacrylate or (1-aryl-1-alkyl)alkyl esters, as well as selectively hydrogenated derivatives thereof, are heated to at least 170.degree. C. in the presence of an amine to convert the polymerized ester to amide and imide groups.

Abstract: A terminal-modified block copolymer having the rest of an amino group or imido group-containing terminal-treating agent bonded to the polymer terminal which is obtained by treating the active terminal of a block copolymer comprising conjugated dienes and vinylaromatic hydrocarbon compounds which is obtained by using as the polymerization initiator at least one member selected from alkali metals or organoalkali metals and has a vinylaromatic hydrocarbon content of 5 to 95% by weight and a number average molecular weight of 5,000 to 1,000,000 with at least one terminal-treating agent selected from imide compounds, cyanamide compounds, aziridinyl compounds, amide compounds, or tertiary amino group-containing compounds other than said compounds; and an adhesive composition excellent in tackiness, adhesiveness, and creep resistance characteristic which comprises said block copolymer and a tackifier resin, 9 water-absorbing composition comprising said block copolymer and a highly water-absorbing resin, a thermoplas

Abstract: A process for preparing bifunctional living polymers which are able to forth bifunctional telechelic polymers or block copolymers with at least 3 blocks of conjugated dienes and/or vinylaromatics with molecular weights of from 1,500 to 500,000, by bifunctional initiators whose anionic centers are aliphatic carbon atoms which are substituted by lithium and an aliphatic hydrocarbon radical as well as by either 2 aryl radicals or by one aryl radical and one hydrogen radical, where one of the aryl radicals can also be part of the two anionic centers, in a first stage being reacted in the presence of not more than 2.5 moles of an aliphatic ether or a tertiary amine per mole of lithium and not less than 2 mol/l of a conjugated diene at from -40.degree. to +35.degree. C. with not less than two moles of diene, resulting in the formation of low molecular weight diene oligomers which in turn act as bifunctional initiators, and using the latter in a second reaction stage in a conventional manner at above 40.degree. C.

Abstract: A method for preparing tapered block copolymers in a polymerization process by charging an initiator and monomers sequentially with one or more charges of first one of the monomers, then with a mixture of the two monomers, and then with one or more charges of the second monomer alternating with one or more charges of the first monomer with subsequent coupling to produce a polymodal tapered block copolymer. Suitable monomers include conjugated dienes and monovinylaromatic compounds. The copolymers are suitable for use in injection and blow molding equipment; the copolymers are particularly useful for shrink films, containers, tubes, fibers and other packaging applications.

Abstract: The present invention relates to hydrogenated block copolymers of butadiene and at least one other diene, preferably isoprene. The copolymer is hydrogenated and comprises at least 10% by weight of at least one crystallizable segment and at least one low crystallinity segment.

Abstract: The present invention is directed to a novel polymodal asymmetric elastomeric block copolymer and a pressure sensitive adhesive and tape made therefrom. The novel block copolymer comprises from about 4 to about 40 percent by weight of a polymerized monovinyl aromatic compound and from about 96 to about 60 percent by weight of a conjugated diene. The block copolymer has the general formula Q.sub.n Y where Q represents an individual arm of the block copolymer and has the formula S-B; n represents the number of arms and is at least 3; and Y is the residue of a multifunctional coupling agent. Furthermore, S is a nonelastomeric polymer segment endblock of a polymerized monovinyl aromatic homopolymer, there being at least two different molecular weight endblocks in the block copolymer. The number average molecular weight of the higher molecular weight endblock (Mn).sub.H is in the range of from about 5,000 to about 50,000, and the number average molecular weight of the lower molecular weight endblock (Mn).sub.

Abstract: There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are polymers of at least one conjugated diene I, e.g., isoprene, which contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms, at least one middle or interior block is a polymer of butadiene, and at least one middle or interior block is a polymer of at least one aryl-substituted olefin, e.g., styrene; or 2) the terminal blocks are random copolymers of at least one diene I as previously defined and butadiene, and at least one middle or interior block is a polymer of at least one aryl-substituted olefin.

Abstract: A method for preparing polymodal tapered block copolymers in a polymerization process by sequentially charging: (a) an initiator and monovinylaromatic monomers in the presence of a randomizer; (b) an initiator and monovinylaromatic monomers; (c) a mixture of monovinylaromatic and conjugated diene monomers; (d) a mixture of monovinylaromatic and conjugated diene monomers; (e) an initiator and monovinylaromatic monomers; (f) a mixture of monovinylaromatic and conjugated diene monomers; (g) a mixture of monovinylaromatic and conjugated diene monomers; (h) conjugated diene monomers; and (i) a coupling agent. The copolymers are particularly useful for packaging applications which require good environmental stress crack resistance.

Abstract: The novel alkadiene/vinyl-aromatic copolymers which contain side groups and have a random, block-like or star-like structure and whose polymerized alkadiene comonomer units are partially or completely selectively hydrogenated, and which contain one or more side groups having one or more radicals capable of (4+2) cycloaddition (Diels-Alder reaction) with dienophiles are suitable as such as viscosity index (VI) improvers or can be used for the preparation of dispersant VI improvers. For this purpose, they are reacted with one or more dienophiles which are capable of a Diels-Alder (4+2) cycloaddition reaction and preferably contain strongly polar functional groups.

Abstract: A solid, cyclone-finishable polymer which does not exhibit cold flow and provides an unexpected balance of viscosity improving properties for oil compositions is produced by hydrogenating a copolymer comprising a homopolymer block of isoprene connected to a copolymer block of isoprene and a monoalkenyl aromatic hydrocarbon. The amount of the monoalkenyl aromatic hydrocarbon is sufficient to allow cyclone finishing although sufficiently distributed to provide oil compositions having good low temperature viscosity. Prior to hydrogenation, the copolymers have a number average molecular weight between 125,000 and 275,000, preferably 150,000 to 240,000, and a total monoalkenyl aromatic content between 10 and 2 percent by weight, preferably between 7 and 3 percent. The copolymer is hydrogenated to substantially saturate the isoprene and to reduce the size of monoalkenyl aromatic segments in the copolymer block.

Abstract: Block copolymers of particular structure comprising blocks of polymerized alkenyl aromatic compound and polymerized conjugated alkadiene, as well as selectively hydrogenated derivatives thereof, are functionalized by the presence of additional polar blocks of polymerized alkyl methacrylate.

Abstract: There are disclosed novel, solid, elastomeric block copolymers with improved resistance to cold flow wherein either 1) the terminal blocks are each a polymer (I polymer) of at least one conjugated diene I, e.g., isoprene, which contains at least five carbon atoms with at least one of each pair of double-bonded carbon atoms in the polymerized diene I units being additionally single-bonded to two carbon atoms; at least one middle or interior block is a hydrogenated polybutadiene (B polymer); and at least one middle or interior block is an essentially straight chain polyethylene (E polymer) resulting from the hydrogenation of a polybutadiene composed of at least 80% of 1,4- units; or 2) the terminal blocks are random IB copolymers of at least one diene I as previously defined and hydrogenated butadiene, and at least one middle or interior block is a straight chain polyethylene (E polymer) as previously defined.

Abstract: Radial and branched block copolymers show a structure: ##STR1## wherein: Z is a radical deriving from a tetrafunctional coupling agent;A is a polystyrene block;B is a polybutadiene blockm, n, p, q are either 1 or zero, with the condition that their sum is comprised within the range of from 1 to 4.Compositions of block copolymers comprise the hereinabove disclosed radial and branched block copolymers, blended with a two-block copolymer B-A, and an "A" homopolymer.The process for the preparation of said radial and branched block copolymers and of the related compositions is disclosed, and furthermore their use is disclosed in bituminous compositions, in order to improve the general characteristics of the bitumens.

Abstract: Polymers comprising blocks of a hydrogenated conjugated diene (B), a vinylarene (A), and an alkyl methacrylate (M), are readily prepared as a mixture of molecules having the structures B-A-M and B-A-M-A-B wherein both structures are effective as viscosity index improvers for oil compositions. Reaction of the polymers with a primary or secondary amine results in a dispersant viscosity index improver.

Abstract: A process is discontinuously preparing continuously tapered SBR-type copolymers optionally having a continuous change in microstructure along the polymer. The process produces tapered block copolymers with multiple glass transition temperatures of very small energy absorption, i.e. no definable glass transition temperature.

Abstract: Butadiene is polymerized alone or with a monomer such as styrene in a dispersion in propane, butane or its mixtures with minor amounts of other C.sub.4 -C.sub.6 alkanes, e.g., n-pentane and a dispersant which is preferably a hydrogenated styrene/ conjugated diene block copolymer to achieve stable dispersions at higher solids and butadiene levels possible with similar alkane dispersants.