Abstract: Hot-melt processable adhesive, such as pressure-sensitive-adhesive (PSA) or heat-activatable adhesive, compositions of the present invention possess a broad formulation latitude and adequate cohesive strength after application for use in high performance applications. Hot-melt processable adhesives of the invention comprise at least one block copolymer comprising at least two A blocks and at least one B block. The A and B blocks are derived from monoethylenically unsaturated monomers, which monomers result in saturated polymer backbones without the need for subsequent hydrogenation upon their polymerization. Preferably, the block copolymer is a (meth)acrylate block copolymer.

Abstract: Disclosed is a process for coupling styrenic block copolymers comprising admixing vinyl cyclohexene dioxide with a living block copolymer comprising at least one block of polymerized vinyl aromatic hydrocarbon monomers and at least one block of polymerized conjugated diene monomers, at a molar ratio of from 0.40 to 0.60 and carrying out a coupling reaction at a temperature of at least 65° C. to produce a coupled styrenic block copolymer. Also disclosed is a polymer composition comprising at most 30% by weight of a styrenic block copolymer comprising at least one block A of polymerized vinyl aromatic monomer(s) and at least one block B of polymerized conjugated diene(s) and at least 70% by weight of the styrenic block copolymer coupled with vinyl cyclohexene dioxide.

Abstract: A novel star block copolymer which can be made to have a high molecular weight and gives a solution having a lower viscosity than solutions of linear polymers having the same molecular weight as the copolymer and which is expected to be used as a resist material; and a process for producing the copolymer. The star block copolymer having alkenylphenol skeletons is obtained by homopolymerizing by living anion polymerization an alkenylphenol compound in which the hydroxyl group of the phenol moiety has been protected by a saturated aliphatic protective group or copolymerizing the alkenylphenol compound with a vinylaromatic compound by living anion polymerization, subsequently copolymerizing the resultant polymer using a polyfunctional coupling agent such as divinylbenzene to obtain a star block copolymer, and eliminating the saturated aliphatic protective groups with an acid reagent.

Abstract: Removing silicon species from hydrocarbon solvents such as cyclohexane. The process comprises contacting the hydrocarbon solvent with sulfuric acid in an amount sufficient to phase separate the silicon species and removing at least 20% by weight of the residual silicon species from the hydrocarbon solvent. The hydrocarbon solvent may be a polymerization solvent containing residual silicon species, and more than 80% by weight of the silicon species can be removed.

Abstract: Disclosed is a process for coupling styrenic block copolymers comprising admixing vinyl cyclohexene dioxide with a living block copolymer comprising at least one block of polymerized vinyl aromatic hydrocarbon monomers and at least one block of polymerized conjugated diene monomers, at a molar ratio of from 0.40 to 0.60 and carrying out a coupling reaction at a temperature of at least 65° C. to produce a coupled styrenic block copolymer. Also disclosed is a polymer composition comprising at most 30% by weight of a styrenic block copolymer comprising at least one block A of polymerized vinyl aromatic monomer(s) and at least one block B of polymerized conjugated diene(s) and at least 70% by weight of the styrenic block copolymer coupled with vinyl cyclohexene dioxide.

Abstract: A combined linear and nonlinear polymer (i.e., having a combined linear, branched and radial structure) P+PnD according to the present invention is represented by (P+PnD)−+Li, where P is a polymer of a monovinyl aromatic monomer or a conjugated diene monomer; PD is a nonlinear polymer having a combined linear, branched and radial structure due to a multifunctional compound D bonded to the polymer P; n is an integer ranging from 2 to 10 and represents the average number of bonds between the monovinyl aromatic or conjugated diene polymer P and the multifunctional compound D; and +Li represents a metal ion as a partner of the active anion (P+PnD)−. The combined linear and nonlinear polymer of the present invention, characterized by nonlinearity-related properties (i.e.

Abstract: Block copolymers comprise at least two hard blocks S1 and S2 made from vinylaromatic monomers and, between these, at least one random soft block B/S made from vinylaromatic monomers and from dienes, where the proportion of the hard blocks is above 40% by weight, based on the total block copolymer.

Abstract: A combined linear and nonlinear polymer (i.e., having a combined linear, branched and radial structure) P+PnD according to the present invention is represented by (P+PnD)−+Li, where P is a polymer of a monovinyl aromatic monomer or a conjugated diene monomer; PD is a nonlinear polymer having a combined linear, branched and radial structure due to a multifunctional compound D bonded to the polymer P; n is an integer ranging from 2 to 10 and represents the average number of bonds between the monovinyl aromatic or conjugated diene polymer P and the multifunctional compound D; and +Li represents a metal ion as a partner of the active anion (P+PnD)−. The combined linear and nonlinear polymer of the present invention, characterized by nonlinearity-related properties (i.e.

Abstract: The present invention relates to a process for the preparation of a dilithiated initiator usable in anionic polymerization, a process for the preparation by anionic polymerization of a living diene elastomer which is provided with a carbon-lithium group at each of its chain ends, and a process for the preparation of a copolymer having three blocks starting from said living diene elastomer. The process for the preparation of a dilithiated initiator according to the invention involves of reacting a first reagent, a dialkenyl benzene, and a second reagent, secondary butyllithium, in the presence of a diamine, in an aliphatic or alicyclic hydrocarbon solvent, such that the ratio of the number of moles of first reagent to the number of moles of second reagent is substantially equal to 0.5, so that the initiator obtained is essentially a bi-adduct resulting from the addition of a molecule of secondary butyllithium to each of the two double bonds in the dialkenyl benzene.

Abstract: The present invention provides a graft polymer composition and its production process and uses, wherein the graft polymer composition is good both in the builder performance and in the compatibility with liquid detergents. The graft polymer composition comprises at least two graft polymers obtained by a process including the step of graft-polymerizing a monoethylenically unsaturated monomer component onto a main chain including a polyether portion, wherein the monoethylenically unsaturated monomer component includes an unsaturated carboxylic monomer as an essential component. And this graft polymer composition is characterized in that there is a difference of not less than 3 in number of carbon atoms in each structural unit which composes ends of the main chain on comparison between two of the at least two graft polymers.

Abstract: A process for preparing a solution of high molecular weight polymers of conjugated dienes in a vinylaromatic hydrocarbon by anionic polymerization of the diene in the presence of an alkyllithium as catalyst and a process for preparing impact-modified polymers of vinylaromatic compounds is described. The first process comprises firstly polymerizing the diene in solution in an aromatic hydrocarbon which is free of ethylenic double bonds to a molecular weight below about 105, then adding a trialkylaluminum in a molar excess relative to the alkyllithium, diluting the solution obtained with the vinylaromatic compound and then coupling the polydiene with a polyepoxide or an alkyl (meth)acrylate to give a high molecular weight polymer. The solution obtained in this way is further processed to give an impact-modified polymer of a vinylaromatic hydrocarbon by polymerizing the solution prepared as described, if desired after addition of further amounts of a vinylaromatic compound, in a manner known per se.

Abstract: The present invention relates to star-block interpolymers having the following structure (X-Y)n-C, wherein X represents a random copolymer block derived from conjugated diene and monovinyl aromatic monomer; Y represents a polyconjugated diene block; C represents a residue derived from a multifunctional lithium based initiator; and n represents the functionality of the initiator and has a value of not less than 3; and preparation of the same. The star-block interpolymers according to the present invention have in the same molecule both a random copolymer block derived from conjugated diene and monovinyl aromatic monomer and a rubber block selected from the group consisting of a homopolymer block derived from conjugated diene, a tapered copolymer block derived from conjugated dienes, a random copolymer block derived from conjugated dienes and combinations thereof, and hence possess excellent properties of the both kinds of rubbers, and can be used widely as elastomeric materials.

Abstract: The present invention discloses processes and apparatus for the efficient and rapid conversion of an elastomeric monomer to a polymerized elastomer, and conjointly, reaction of the resultant rubbery polymer into a monovinylaromatic polymerization reaction to form a rubber-modified polymer; and more specifically teaches a method of polymerizing butadiene and reacting it with styrene monomer to form a transparent rubber-modified impact-resistant polystyrene material exhibiting elastomer concentrations that range from as low as 6 weight percent or lower, to as high as about 50 percent.

Abstract: A process of preparing a diblock/triblock composition in a single reaction vessel includes reacting a first monomer, such as styrene, with a first portion of an anionic catalyst in a suitable solvent to form a first polymer block of the triblock. A second step includes adding a second monomer, such as butadiene (when the first monomer is styrene). This forms a second block of the triblock and a first block of the diblock. A further addition of the first monomer completes the diblock and triblock interpolymers. At least a portion of the diblock and/or triblock interpolymers are functionally terminated with a functional terminating agent, such as cyclohexene oxide or isopropanol, to provide the blocks with a functional group. The functional group and the proportion of the interpolymers functionally terminated are selected to provide desired adhesive properties for a particular application.

Abstract: The present invention relates to butadiene/isoprene/monovinyl aromatic monomer heptablock copolymers having the following symmetric structure: Z-XZ-X-Y-X-XZ-Z wherein Z represents a polymer block of monovinyl aromatic monomer, X and Y, being different from each other, represent polymer blocks of butadiene or isoprene, XZ represents a tapered copolymer block of monovinyl aromatic monomer and butadiene or isoprene, and wherein the content of the recurring units derived from monovinyl aromatic monomer is 10 to 50 percent by weight, the content of the recurring units derived from butadiene is 10-75 percent by weight and the content of the recurring units derived from isoprene is 10-75 percent by weight, all based on the weight of the block copolymer, and methods for the preparation thereof.

Abstract: A polymer composition comprising at least two end segments that make up less than 15% of the total polymer composition. Each end segment has a vinyl content greater than about 45%. However, the vinyl content is less than about 35% throughout the remainder of the polymer composition.

Abstract: The invention provides solid supported anionic catalysts, suitable for gas phase anionic polymerization of conjugated diene monomers, that are useful for anionically producing very high molecular weight branched diene polymers, such as styrene butadiene rubber, polybutadiene rubber, polyisoprene rubber, and the like. The catalysts comprise a metalatable particle, such as a bound rubber, a thermoplastic polymer or a cured elastomer, that is multiply metalated with Group IA alkali metal atoms. The multi-branched diene polymers obtained by gas phase anionic polymerization employing the catalysts exhibit desirable properties, such as an extremely high molecular weight, a controlled molecular weight distribution, Tg and vinyl content, and the ability to readily absorb hydrocarbon solvents and oils. The polymers are easily compounded to form vulcanizable elastomeric compounds and articles, such as tires, that have excellent resistance to wear and tear and exhibit reduced hysteresis properties.

Abstract: Block copolymers having a molecular weight distribution of between 1.0 and 5.0 comprising at least one block of polymerized alkyl methacrylate monomer(s), wherein from 50 to 100% by weight of the monomers for forming the alkyl methacrylate block are C12-C30 alkyl methacrylates, and a block of a polymerized conjugated alkadiene. The block copolymers of the present invention are useful as viscosity index improvers in lubricating oil compositions as well as compatibilizers for compositions containing both polymethacrylates and olefin copolymers or hydrogenated block polymers.

Abstract: A thermoplastic elastomer produced without a hydrogenation step is functionalized utilizing a free radical initiator and a functionalizing monomer having at least one point of unsaturation. The base polymers can be produced by copolymerizing an &agr;-olefin capable of producing an amorphous backbone with a comonomer which provides a “hook” for grafting to with a living polystyrene chain. Another method is to copolymerize an &agr;-olefin monomer system capable of producing an amorphous backbone with a comonomer containing a functional group from which an anionically polymerizable monomer is grown from the backbone. A third method involves copolymerizing an &agr;-olefin monomer system capable of giving an amorphous backbone with an olefin-terminated polystyrene comonomer. In a less preferred embodiment a conventional EPDM polymer can be metallated and a monoalkenyl aromatic compound anionically polymerizable monomer grown from the backbone.

Abstract: This invention discloses a process for synthesizing random styrene-isoprene rubber comprising: (1) continuously charging isoprene, styrene, an initiator, and a solvent into a first polymerization zone, (2) allowing the isoprene and styrene to copolymerize in the first polymerization zone to total conversion of 60 to 95 percent to produce a polymer cement containing living styrene-isoprene chains, (3) continuously charging the polymer cement containing living styrene-isoprene chains and additional isoprene monomer into a second polymerization zone, wherein from 5 to 40 percent of the total amount of isoprene changed is charged into the second polymerization zone, (4) allowing the copolymerization to continue in the second polymerization zone to a conversion of the isoprene monomer of at least 90 percent wherein the total conversion of styrene and isoprene in the second polymerization zone is limited to a maximum of 98 percent, (5) withdrawing a polymer cement of random styrene-isoprene rubber having living cha

Abstract: Disclosed is a rubbery polymer comprising a conjugated diene polymer, and bonded thereto, a lithium-detached residue of a lithium-containing organic polymer used as a catalyst in the production of the conjugated diene polymer, wherein the lithium-containing organic polymer is obtained by reacting an organolithium compound with a first polymerizable material comprising at least one conjugated diene monomer and a second polymerizable material comprising at least one aromatic vinyl compound, which second polymerizable material contains at least one multi-vinyl aromatic compound having at least two vinyl groups, and wherein the lithium-containing organic polymer has a specific narrow molecular weight distribution.

Abstract: The anionic polymerization of dienes or copolymers of dienes and vinylaromatic monomers in a vinylaromatic monomer or monomer mixture to give homopolydienes or copolymers or mixed homopolydienes and copolymers is carried out in the presence of a metal alkyl or aryl of an element having a valence of at least two without addition of Lewis bases.

Abstract: A process for reducing the water take up of a vinyl aromatic-conjugated diene polymer when subjected to a humid environment, the process comprising solution polymerising at least one vinyl aromatic hydrocarbon and a conjugated diene in the presence of a catalyst based on an alkali metal to produce alkalimetal derivatives of a vinyl aromatic-conjugated diene polymer and neutralising the derivatives with a C9-C16 alkyl dicarboxylic acid.

Abstract: A process for producing a vinyl aromatic-conjugated diene block copolymer, the process comprising solution polymerising at least one vinyl aromatic hydrocarbon and a conjugated diene in the presence of a catalyst based on an alkali metal to produce copolymer chains which end with an alkali metal and treating the copolymer chains in solution with an alkyl dicarboxylic acid having at least 2 carbon atoms and the acid being in the form of a slurry in an organic liquid with the acid being granulated and having an average granule size of less than 50 microns.

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 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: New oximsulfonate compounds of formulae (I) or (II), wherein m is 0 or 1; x is 1 or 2; R1 is, for example phenyl, which is unsubstituted or substituted or R1 is a heteroaryl radical that is unsubstituted or substituted, or, if m is 0, R1 additionally is C2-C6alkoxycarbonyl, phenoxycarbonyl or CN; R′1 is for example C2-C12alkylene, phenylene; R2 has for example one of the meanings of R1; n is 1 or 2; R3 is for example C1-C18alkyl, R′3 when x is 1, has one of the meanings given for R3, or R′3 in formula (IV) and when x is 2 in formula (I), is for example C2-C12 alkylene, phenylene; R4 and R5 are independently of each other for example hydrogen, halogen, C1-C6alkyl; R6 is for example hydrogen, phenyl; R7 and R8 are independently of each other for example hydrogen or C1-C12alkyl; R9 is for example C1-C12alkyl; A is S, O, NR6, or a group of formula (A1), (A2), (A3) or (A4); R10 and R11 independently of each other have one of the meanings given for R4; R12, R13, R14 and R15 independently of one an

Abstract: The dispersibility of the initial polystyrene block in forming a S-B-S type of copolymer is improved by first preparing a small block of homopolydiene such as homopolybutadiene as a dispersing agent. Onto this small block of homopolybutadiene, the first block of polystyrene is formed and affixed and thereby made dispersible in a mixture of alkanes and 15 to 60% by weight of cycloalkanes, preferably hexane and cyclohexane. After the preparation of the dispersing agent and the first styrene block, the remaining monomer charges to the reactor are fed in aliphatic hydrocarbon diluents, preferably hexane or technical hexane, thereby greatly reducing the final percentage of cycloalkanes including cyclohexane in the reactor to less than 25% of total dispersing medium. The block copolymers produced according to the present process display a narrow molecular weight distribution and improved tensile strength over block copolymers produced in the absence of the additional cycloalkanes in the solvent system.

Abstract: Polymers are produced by alternate anionic polymerization of conjugated dienes and/or monomalkenyl arenes to form a living polymer chain, followed by precise incorporation of protected functional groups into that living polymer chain.

Abstract: Disclosed herein are an aromatic vinyl-conjugated diene block copolymer composed of a bound aromatic vinyl unit and a bound conjugated diene unit and containing at least a block aromatic vinyl segment, wherein:(1) a content of the bound aromatic vinyl unit in the block copolymer is 3 to 60 wt. %;(2) a proportion of block aromatic vinyl segment portions having a molecular weight at most a third of a molecular weight (A-Mp) corresponding to a peak in a molecular weight distribution curve of the block aromatic vinyl segment (A) as determined by gel permeation chromatography (GPC) is 55 to 90 mol % based on the total content of the block aromatic vinyl segment (A); and(3) a molecular weight (Mp) corresponding to a peak in a molecular weight distribution curve of the block copolymer as determined by GPC is 10,000 to 1,000,000, a production process thereof, a resin composition comprising the aromatic vinyl-conjugated diene block copolymer, and a preparation process of the resin composition.

Abstract: A process for interpolymerizing a vinyl aromatic hydrocarbon polymer and a block polymer is disclosed. The process includes the following steps: (a) forming a block polymer precursor of at least one polymeric block containing conjugated diene monomer contributed units in the presence of an anionic initiator and in an inert diluent, the block polymer precursor having living ends; and (b) thereafter adding to the block polymer precursor a charge of a vinyl aromatic hydrocarbon monomer and an additional charge of an anionic initiator to simultaneously form (1) a block polymer having a terminal block formed from the charge of vinyl aromatic hydrocarbon monomer attached to the block polymer precursor and (2) a poly(vinyl aromatic hydrocarbon) polymer interpolymedzed with the block polymer. The practice of this process produces a vinyl aromatic hydrocarbon block terminated block polymer, such as SBS, interpolymerized with a polymer formed from vinyl aromatic hydrocarbon monomer, such as polystyrene.

Abstract: This invention relates to a thermoplastic elastomeric block copolymer and process for the preparation thereof. According to this invention, the block copolymer obtained through block copolymerization process at higher temperature and adding butyllithium in twice during copolymerization are mixed block copolymer of A.sub.1 -B-A.sub.2 /B-A.sub.2 and B-A.sub.2 /B-A.sub.2 (where A represents monovinyl aromatic monomer; B represents conjugated diene monomer) having different blocks, higher elongation and appropriate melt index. The process of this invention is simple and efficient. The thermoplastic elastomeric block copolymer of this invention are particularly useful for various applications of typical styrene butadiene block copolymer, especially plastic modifier.

Abstract: Novel solid supported anionic polymerization initiators that are multiply metalated with Group IA alkali metal atoms are provided and employed to produce extremely high molecular weight branched diene polymers. The initiators are prepared by metalating a particle comprising a thermoplastic polymer or a cured elastomer in the presence of a polar coordinator. The polymers obtained by anionic polymerization employing the initiators are multiply branched, with a polymer chain covalently attached to the particle at virtually every metalation site. The macro-branched polymers exhibit desirable properties, such as an extremely high molecular weight, a controlled molecular weight distribution, T.sub.g and vinyl content, and the ability to readily absorb hydrocarbon solvents and oils. The polymers are easily compounded to form vulcanizable elastomeric compounds and articles that have excellent resistance to wear and tear and exhibit reduced hysteresis properties.

Abstract: This invention provides a process to produce coupled block copolymers and said coupled block copolymers.

Abstract: Disclosed are ionomers comprising functionalized polyolefins having fluoroalkyl sulfonate pendant groups and ionically conductive compositions formed therefrom by the addition of solvents.

Abstract: A thermoplastic elastomer produced without a hydrogenation step is functionalized utilizing a free radical initiator and a functionalizing monomer having at least one point of unsaturation. The base polymers can be produced by copolymerizing an .alpha.-olefin capable of producing an amorphous backbone with a comonomer which provides a "hook" for grafting to with a living polystyrene chain. Another method is to copolymerize an .alpha.-olefin monomer system capable of producing an amorphous backbone with a comonomer containing a functional group from which an anionically polymerizable monomer is grown from the backbone. A third method involves copolymerizing an .alpha.-olefin monomer system capable of giving an amorphous backbone with an olefin-terminated polystyrene comonomer. In a less preferred embodiment, a conventional EPDM polymer can be metallated and a monoalkenyl aromatic compound anionically polymerizable monomer grown from the backbone.

Abstract: This invention discloses a process for synthesizing a styrene-butadiene polymer, which is particularly useful for modifying asphalt to improve force ductility, elastic recovery, toughness and tenacity, by a process which comprises the steps of: (1) continuously charging 1,3-butadiene monomer, an organo lithium compound, a polar modifier and an organic solvent into a first polymerization zone, (2) allowing the 1,3-butadiene monomer to polymerize in said first polymerization zone to a conversion of at least about 90 percent to produce a living polymer solution which is comprised of said organic solvent and living polybutadiene chains having a number average molecular weight which is within the range of about 20,000 to about 60,000, (3) continuously withdrawing said living polymer solution from said first reaction zone, (4) continuously charging styrene monomer, divinyl benzene and the living polymer solution being withdrawn from the first polymerization zone into a second polymerization zone, (5) allowing the s

Abstract: Living random (meth)acrylic copolymers, facilely converted into random co(meth)acrylates and block copolymers thereof, comprise the anionic copolymerizates of at least one comonomer A with at least one comonomer B selected from among the (meth)acrylates and maleimides, at least one of the comonomers A and B comprising a (meth)acrylate, in the presence of (i) at least one alkali or alkaline earth metal, mono- or difunctional initiator and (ii) at least one ligand, for example a nonnitrogenous macrocyclic complexant, e.g., a crown ether, or an alkali metal alcoholate.

Abstract: This invention discloses a process for synthesizing a styrene-butadiene polymer which comprises the steps of: (1) continuously charging 1,3-butadiene monomer, an organolithium compound, a polar modifier and an organic solvent into a first polymerization zone, (2) allowing the 1,3-butadiene monomer to polymerize in said first polymerization zone to a conversion of at least about 90 percent to produce a living polymer solution, (3) continuously withdrawing said living polymer solution from said first polymerization zone, (4) continuously charging divinyl benzene and the living polymer solution being withdrawn from the first polymerization zone into a second polymerization zone, (5) allowing the divinyl benzene monomer to react with the living polybutadiene chains in said second polymerization zone to produce a solution of living divinylbenzene modified butadiene polymer, (6) continuously withdrawing the solution of said divinylbenzene modified butadiene polymer from the second polymerization zone, (7) continuou

Abstract: Processes for the preparation of a thermoplastic elastomer comprising a triblend of engineering resin, dynamically vulcanized alloy of thermoplastic olefin polymer and elastomeric copolymer, and a compatibilizer for the engineering resin and alloy. The compatibilizer can be formed in a separate step or in-situ in a one step process. The processes produce compositions which retain structural integrity at high temperature, and have good tensile properties, elongation and fluid resistance.

Abstract: A rubber composition having good breaking properties, high tan.delta., good wear resistance and a method for preparing a copolymer used in the rubber composition. The copolymer is a butadiene-styrene copolymer prepared in the presence of an organopotassium compound, an oxolanyl alkane and an organolithium initiator compound. The copolymer may be modified. A vulcanite of the rubber composition including 20 parts or more of the copolymer of the present invention has good properties.

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 multifunctional anionic polymerization initiator which is in the form of a star-shaped polymer, and which is soluble in a nonpolar medium and is 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 for the polymerization of dienes which comprises anionically polymerizing dienes in the presence of an anionic polymerization initiator and a microstructure control agent is improved by adding the control agent to the polymerization mixture in two or more doses to closely control the vinyl content of the polymer produced.

Abstract: This invention concerns novel, unsymmetrically protected, telechelically functionalized linear and star or multi-arm polymers, their optionally hydrogenated analogues, the polymers produced by selective removal of the protecting groups, the segmented block polymers produced by further reaction of these selectively deprotected polymers with selected comonomers, and the processes to prepare these polymers.

Abstract: In the production of "inside-out" star polymers where a first polymer lithium chain is formed, coupled and thereafter additional monomer is introduced to produce the "out" polymer chains, improved control over the second polymerization is obtained by coupling with a mixture of a monoalkenyl-substituted aromatic compound and a polyalkenyl-substituted aromatic compound. For example, a mixture of divinylbenzene and styrene can be used. In another embodiment, an ether is introduced after completion of the first polymer chain formation. The presence of the ether also improves the second stage chain formation. Utilization of both the mixed coupling agents and the ether, preferably a diether such as 1,2-diethoxyethane gives the greatest control over the uniformity of the second stage polymerization, making possible the production of narrower molecular weight distribution polymer having no indication of bimodal distribution. The narrow molecular weight distribution is advantageous in many applications.

Abstract: A light scattering material is prepared by mixing with and dispersing in a transparent elastomer matrix particles of a transparent material. The matrix has a Tg of lower than room temperature and the transparent material has a different index of refraction form the matrix.

Abstract: A multifunctional anionic polymerization initiator which is in the form of a star-shaped polymer, and which is soluble in a nonpolar medium and is 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 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 monovtnylarene monomer, (ii) a mixture of monovtnylarene monomer and conjugated diene monomor, (iii) a conjugated diene monomer, (iv) a monovinylarene monomer;(d) a 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 least 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: Block copolymer compositions, comprising for a major part of linear triblock copolymers, comprising two terminal predominantly poly(monovinylaromatic) blocks having a real molecular weight in the range of from 5,000 to 25,000 and one predominantly poly(boutadiene) midblock, said triblock copolymer having a monovinylaromafic content in the range of from 10 to 55 wt %, an apparent total molecular weight in the range of from 15,000 to 300,000, and an amount of from 0 to 40 wt % of a diblock copolymer relative to the total block copolymer composition weight, containing a predominantly poly(monovinylaromatic) block and a predominantly poly(boutadiene) block similar to those of the triblock copolymer component; said block copolymer composition having a free poly(vinylaromatic) content of at most 7 wt %, and shaped articles derived from said block copolymer composition.