Abstract: The subject invention relates to an anionic polymerization technique for synthesizing rubbery polymers of conjugated diolefin monomers, such as rubbery copolymer of .alpha.-methylstyrene and 1,3-butadiene. These rubbery copolymers exhibit an excellent combination of properties for utilization in tire tread rubber compounds. They have high trans-isomer contents which leads to good treadwear characteristics and a broad molecular weight distribution which enhances processability.

Abstract: The subject invention relates to an anionic polymerization technique for synthesizing rubbery polymers of conjugated diolefin monomers, such as a rubbery copolymer of .alpha.-methylstyrene and 1,3-butadiene. These rubbery copolymers exhibit an excellent combination of properties for utilization in tire tread rubber compounds. They have high trans-isomer contents which leads to good treadwear characteristics and a broad molecular weight distribution which enhances processability.

Abstract: A process for the preparation of hydrocarbon solutions of monofunctional ether initiators of the following general structure:M--Z--O--C(R.sup.1 R.sup.2 R.sup.3)wherein M is an alkali metal; Z is a branched or straight chain hydrocarbon group which contains 3-25 carbon atoms, optionally containing aryl or substituted aryl groups; and R.sup.1, R.sup.2, and R.sup.3 are independently selected from hydrogen, alkyl, substituted alkyl, aryl or substituted aryl groups, and their employment as initiators in the anionic polymerization of olefin containing monomers in an inert, hydrocarbon solvent comprising reacting an omega-protected-1-haloalkyl with lithium metal dispersion having a particle size between 10 and 300 millimicrons in size, at a temperature between 35.degree. and 130.degree. C. in an alkane solvent containing 5 to 10 carbon atoms.

Abstract: This invention reveals an initiator system which is comprised of (a) a lithium initiator, (b) a sodium alkoxide, and (c) a polar modifier; wherein the molar ratio of the sodium alkoxide to the polar modifier is within the range of about 0.1:1 to about 10:1; and wherein the molar ratio of the sodium alkoxide to the lithium initiator is within the range of about 0.01:1 to about 20:1.

Abstract: The anionic polymerization of unsaturated monomers with functionalized initiators having the structure R.sup.1 R.sup.2 R.sup.3 Si--O--A'--Li is improved by selecting A' from the structures --CH.sub.2 --CH.sub.2 --CH.sub.2 -- (1,3-propyl), --CH.sub.2 --CH(CH.sub.3)--CH.sub.2 -- (2-methyl-1,3-propyl), --CH.sub.2 --C(CH.sub.3).sub.2 --CH.sub.2 --(2,2-dimethyl-1,3-propyl), or --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --(1,8-octyl). This narrow class of polymerization initiators operate at surprisingly higher polymerization temperatures with surprisingly lower amounts of dead initiator than similar initiators wherein A' is --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --(1,4-butyl), --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --(1,5-pentyl), or --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --(1,6-hexyl).

Abstract: A multifunctional initiator is prepared by contacting an organo-alkali metal compound with a silane represented by the formula: ##STR1## wherein the R' are generally lower alkyl groups such as methyl and the R" is generally an .paren open-st.CH.sub.2 .paren close-st..sub.n group with n=2. Superior results are obtained presumably because of the separation of the vinyl groups and the greater solubility of the compound because of the R' groups. The resulting catalyst initiates polymerization of monomers such as conjugated dienes and monovinyl substituted aromatic compounds to give relatively monodispersed polymers with little or no crosslinking.

Abstract: A process for the preparation of hydrocarbon solutions of monofunctional ether initiators of the following general structure:M--Z--O--C(R.sup.1 R.sup.2 R.sup.3)wherein M is an alkali metal; Z is a branched or straight chain hydrocarbon group which contains 3-25 carbon atoms, optionally containing aryl or substituted aryl groups; and R.sup.1, R.sup.2, and R.sup.3 are independently selected from hydrogen, alkyl, substituted alkyl, aryl or substituted aryl groups, and their employment as initiators in the anionic polymerization of olefin containing monomers in an inert, hydrocarbon solvent comprising reacting an omega-protected-1-haloalkyl with lithium metal dispersion having a particle size between 10 and 300 millimicrons in size, at a temperature between 35.degree. and 130.degree. C. in an alkane solvent containing 5 to 10 carbon atoms.

Abstract: A process for the preparation of hydrocarbon solutions of monofunctional ether initiators of the following general structure:M--Z--O--C(R.sup.1 R.sup.2 R.sup.3)wherein M is an alkali metal; Z is a branched or straight chain hydrocarbon group which contains 3-25 carbon atoms, optionally containing aryl or substituted aryl groups; and R.sup.1, R.sup.2, and R.sup.3 are independently selected from hydrogen, alkyl, substituted alkyl, aryl or substituted aryl groups, and their employment as initiators in the anionic polymerization of olefin containing monomers in an inert, hydrocarbon solvent comprising reacting an omega-protected-1-haloalkyl with lithium metal dispersion having a particle size between 10 and 300 millimicrons in size, at a temperature between 35.degree. and 130.degree. C. in an alkane solvent containing 5 to 10 carbon atoms.

Abstract: A process for the preparation of hydrocarbon solutions of monofunctional ether initiators of the following general structure:M--Q.sub.n --Z--OA(R.sup.1 R.sup.2 R.sup.3) (II)wherein M is defined as an alkali metal, selected from the group consisting of lithium, sodium and potassium, Q is a saturated or unsaturated hydrocarbyl group derived by incorporation of a compound selected from the group consisting of conjugated diene hydrocarbons and alkenylsubstituted aromatic hydrocarbons; Z is defined as a branched or straight chain hydrocarbon tether or connecting group which contains 3-25 carbon atoms, optionally containing aryl or substituted aryl groups; A is an element selected from Group IVa of the periodic table and R.sup.1, R.sup.2, and R.sup.3 are independently selected from hydrogen, alkyl, substituted alkyl, aryl or substituted aryl groups, and n is an integer from 1 to 5.

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: 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 process for producing a diolefin polymer or copolymer, comprising the steps of polymerizing 55-100 wt % of a conjugated diolefin with 0-45 wt % of an aromatic vinyl compound as monomers in a hydrocarbon as a solvent, by using initiators: a reaction product [a1] between at least one secondary amine compound (A) and an organic lithium compound and/or a lithium amide compound [a2] of the at least one secondary amine compound (A) as well as a reaction product [b1] between at least one alcohol (B) and an organic lithium compound and/or a lithium alkoxide compound of the at least one alcohol (B). A rubber composition containing not less than 30 wt % of such a diolefin polymer or copolymer with respect to an entire rubber component is also disclosed. This rubber composition exhibits excellent abrasion resistance, high tensile strength, steering stability and low rolling resistance, and is suitable for tires, particularly, as treads of low fuel consumption tires.

Abstract: A method for preparing a telechelic polydiene having at least 70% 1,4-microstructure and at least 70% of its end groups capped by reactive silyl functionality is disclosed, said method comprising:(I) reacting, in a non-polar solvent solution,(A) at least one diene monomer,(B) a dianionic initiator which is soluble in said non-polar solvent and, optionally,(C) a polymerization adjuvant to form a dianionically active polydiene; and(II) capping both ends of said dianionically active polydiene from step (I) with(D) a silane, said capping being carried out in the presence of(E) a promoter selected from the group consisting of a tertiary amine and a crown ether based on 12-crown-4.

Abstract: The subject invention relates to a technique for synthesizing rubbery copolymers of styrene and isoprene. These rubbery copolymers exhibit an excellent combination of properties for utilization in tire tread rubber compounds. By utilizing these styrene-isoprene rubbers in tire treads, tires having improved wet skid resistance can be built without sacrificing rolling resistance or tread wear characteristics.

Abstract: It has been unexpectedly discovered that various compounds, such as alkyl tetrahydrofurfuryl ethers, can be used to modify anionic polymerizations of conjugated diene monomers. These modifiers can be used to polymerize isoprene monomer into high 3,4-polyisoprene at excellent polymerization rates. This is in contrast to the modifiers such as tetramethylethylene diamine which are typically used to modify such polymerizations. This invention more specifically discloses a process for the synthesis of 3,4-polyisoprene which comprises polymerizing isoprene monomer in an organic solvent in the presence of a catalyst system which is comprised of (a) a lithium initiator and (b) an alkyltetrahydrofurfuryl ether modifier, wherein the alkyl group in the alkyltetrahydrofurfuryl ether modifier contains from 6 to about 10 carbon atoms.

Abstract: Provided is a process useful for making acrylic polymers of methacrylic acid having improved shear stability. The process provides polymers useful as enteric coatings for medicaments having improved coating efficiency of pharmaceutical forms. Also provided are medicaments in solid form coated with said polymers.

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: The subject invention relates to a technique for synthesizing rubbery copolymers of styrene and isoprene. These rubbery copolymers exhibit an excellent combination of properties for utilization in tire tread rubber compounds. By utilizing these styrene-isoprene rubbers in tire treads, tires having improved wet skid resistance can be built without sacrificing rolling resistance or tread wear characteristics. This invention more specifically discloses a process for the synthesis of styrene-isoprene rubbers which comprises copolymerizing isoprene monomer and styrene monomer in an organic solvent in the presence of a catalyst system which is comprised of (a) a lithium initiator and (b) an alkyl tetrahydrofurfuryl ether modifier, wherein the molar ratio of the modifier to the lithitium initiator is within the range of 2:1 to 40:1.

Abstract: It has been unexpectedly discovered that various compounds, such as alkyl tetrahydrofurfuryl ethers, can be used to modify anionic polymerizations of conjugated diene monomers. These modifiers can be used to polymerize isoprene monomer into high 3,4-polyisoprene at excellent polymerization rates. This is in contrast to the modifiers such as tetramethylethylene diamine which are typically used to modify such polymerizations. This invention more specifically discloses a process for the synthesis of 3,4-polyisoprene which comprises polymerizing isoprene monomer in an organic solvent in the presence of a catalyst system which is comprised of (a) a lithium initiator and (b) a modifier which is an alkyltetrahydrofurfuryl ether selected from the group consisting of ethyltetrahydrofurfuryl ether, propyltetrahydrofurfuryl ether, and butyltetrahydrofurfuryl ether.

Abstract: A process for making porous polymeric particles having high surface area includes suspending a discontinuous organic phase in an continuous aqueous phase, wherein the organic phase includes an ethylenically unsaturated monomer, a water soluble phase extender and a surfactant in an amount effective to solubilize the water soluble phase extender in the monomer and wherein the aqueous phase includes a diffusion barrier agent for limiting mass transfer of the phase extender from the organic phase to the aqueous phase, and then polymerizing the ethylenically unsaturated monomer to form the porous polymeric particles.

Abstract: This invention concerns a "living" free radical polymerization process for preparing polymers having a narrow distribution of molecular weights.

Abstract: It has been unexpectedly discovered that salts of tetrahydrofurfuryl alcohols, such as the lithium, potassium, and sodium salts of tetrahydrofuryl alcohols, can be used to modify anionic polymerizations of conjugated diene monomers. These modifiers can be used to polymerize isoprene monomer into polyisoprene having from 20% to 30% 1,2-microstructure at excellent polymerization rates. This invention more specifically discloses a catalyst system which is particularly useful in the anionic polymerization of conjugated diene monomers into polymers which is comprised of (a) a initiator which is selected from the group consisting of organolithium compounds, organosodium compounds, organopotassium compounds, organomagnesium compounds, and organobarium compounds, and (b) a modifier which is a metal salt of a tetrahydrofurfuryl alcohol.

Abstract: This system for priming the animic polymerization of (meth)acrylates includes at least one primer of the formula R--M (I) in which M represents a metal selected from alkaline and alkaline earth metals and R represents an alkyl radical with a straight or branched chain containing 2 to 6 atoms of carbon or an aryl radical or an arylalkyl radical. H is characterized in that it further contains at least one organic derivative of an alkaline metal, with the proviso that said organic derivative is neither an alcoholate nor a carboxyl acid ester substituted in position .alpha. by said metal. Applications in the anionic polymerization of (meth)acrylates.

Abstract: It has been unexpectedly discovered that various compounds, such as alkyl tetrahydrofurfuryl ethers, can be used to modify anionic polymerizations of conjugated diene monomers. These modifiers can be used to polymerize isoprene monomer into high 3,4-polyisoprene at excellent polymerization rates. This is in contrast to the modifiers such as tetramethylethylene diamine which are typically used to modify such polymerizations. This invention more specifically discloses a process for the synthesis of 3,4-polyisoprene which comprises polymerizing isoprene monomer in an organic solvent in the presence of a catalyst system which is comprised of (a) a lithium initiator and (b) ethyltetrahydrofurfuryl ether.

Abstract: An improved process for the production of conjugated alkadiene-based polymers of higher vinyl content employs as a structure modifier a compound of the formula ##STR1## wherein R is alkylene, R' alkyl and R" is hydrogen or hydrocarbyl.

Abstract: Random or block copolymers with (1-hydro-1-R-1-sila-cis-pent-3-ene), poly(1-hydro-1-R-3,4 benzo-1-sila pent-3-ene), and disubstituted 1-silapent-3-ene repeating units of the general formula ##STR1## where R is hydrogen, an alkyl radical containing from one to four carbon atoms or phenyl, R.sup.1 is hydrogen, an alkyl radical containing from one to four carbon atoms, phenyl or a halogen and R.sup.2 is hydrogen, or R.sup.1 and R.sup.2 are combined to form a phenyl ring, are prepared by the anionic ring opening polymerization of silacyclopent-3-enes or 2-silaindans with an organometallic base and cation coordinating ligand catalyst system or a metathesis ring opening catalyst system.

Abstract: An organic compound of an alkali metal, of the formula I ##STR1## which is obtained by reaction of an appropriate diarylethylene of the formula II with an alkali metal (M), especially lithium, ##STR2## where Ar.sup.1 and Ar.sup.2 are identical or different aryl or hetaryl radicals which have one or more rings which are either separate or fused, and where R is at least one substituent different from hydrogen and which is chemically inert to the alkali metal or its alkyl, with the proviso that the total of the carbon atoms in all the R is at least 3, and m and n are each an integer up to 4, is used for the preparation of polymers whose monomers are amenable to anionic polymerization.

Abstract: Poly(1-hydro-1-R-1-sila-cis-pent-3-ene) and poly(1-hydro-1-R-3,4 benzo-1-sila pent-3-ene) polymers having repeating units of the general formula ##STR1## where R is hydrogen, an alkyl radical containing from one to four carbon atoms or phenyl, R.sup.1 is hydrogen, an alkyl radical containing from one to four carbon atoms, phenyl or a halogen and R.sup.2 is hydrogen, or R.sup.1 and R.sup.2 are combined to form a phenyl ring, are prepared by the anionic ring opening polymerization of silacyclopent-3-enes or 2-silaindans with an organometallic base and cation coordinating ligand catalyst system.

Abstract: A method for preparing a diene polymer or copolymer having increased amounts of 1,2-microstructure is provided. The method involves polymerizing a diene monomer or mixture of a diene monomer and a vinyl aromatic hydrocarbon monomer in a hydrocarbon solvent in the presence of a catalytically effective amount of a catalyst composition comprising: (a) an organolithium initiator and (b) an oxolanyl cyclic acetal having the structural formula: ##STR1## wherein R is selected from the group consisting of hydrogen and alkyl groups containing from 1 to 4 carbon atoms and X is 0 or 1.

Abstract: A block-free polymer is prepared by anionically polymerizing at least two compounds selected from the groups consisting of butadiene, isoprene and styrene in an inert organic solvent in the presence of an organolithium compound as a catalyst and a cocatalyst of a glycol dialkyl ether: ##STR1## wherein R.sub.3 is hydrogen, methyl or ethyl, R.sub.1 and R.sub.2 are alkyl groups of different numbers of carbon atoms selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, sec-butyl and t-butyl, and the total number of carbon atoms in the alkyl group ranges from 5 to 7.

Abstract: Trans-1,4-polybutadiene is a thermoplastic resin rather than a rubber at room temperature by virtue of its high degree of crystallinity. Because trans-1,4-polybutadiene contain many double bonds in its backbone, it can be blended and cocured with rubbers. It is accordingly an attractive alternative to conventional fillers such as carbon black, which are typically utilized in compounding rubber. By utilizing the catalyst system and techniques of this invention, trans-1,4-polybutadiene can be synthesized at a high level of conversion. This invention specifically relates to a process for the synthesis of trans-1,4-polybutadiene by an anionic polymerization process which comprises: (a) adding an alkali metal trialkylmagnesiate and an alkali metal alkoxide as a catalyst system to a polymerization medium containing 1,3-butadiene monomer and an organic solvent; and (b) allowing the 1,3-butadiene monomer to polymerize at a temperature which is within the range of about -10.degree. C. to about 50.degree. C.

Abstract: Process for the preparation of polymers by anionic (co)polymerization of ethylenically unsaturated organic monomers in the presence of an arylmethide initiator of the following general structure: ##STR1## wherein: X.sup.+ represents a cation;Y and Z (same or different) represent a hydrogen atom or an alkyl group;Ar represents a condensed aromatic group, including a substituted condensed aromatic group.

Abstract: A catalyst composition for polymerizing a conjugated diene which comprises the following (a), (b) and (c) components:(a) an organolithium-aluminum compound represented by the formula:LiAlR.sup.1 R.sup.2 R.sup.3 R.sup.4(b) an organobarium-aluminum compound represented by the formula:Ba(AlR.sup.1 R.sup.2 R.sup.3 R.sup.4).sub.2 or Ba[AlR.sup.1 R.sup.2 R.sup.3 (OR.sup.4)].sub.2(c) a lithium alkoxide represented by the formula:LiOR.sup.5The conjugated diene polymer or copolymer obtained by polymerizing a conjugated diene alone or in combination with other monomer with the above catalyst composition in an inert organic solvent has a high trans-1,4 bond content, a low vinyl bond content and a low cis-1,4 bond content.

Abstract: Polyisoprenes having a high content of 1,2- and 3,4-structural units, a process for their preparation, and their use.The previous processes for the preparation of polyisoprene having a high content of 1,2- and 3,4-structural units were still unsatisfactory in terms of the cocatalyst employed.The use of ethylene glycol dialkyl ethers of the formulaR.sub.1 --O--CH.sub.2 --CH.sub.2 --O--R.sub.2in which R.sub.1 and R.sub.2 are alkyl groups having different numbers of C atoms, from the group consisting of methyl, ethyl, n- and isopropyl and n-, iso-, sec.- and tert.-butyl, has, in particular, the advantage that the "living polymers" formed during the anionic polymerization are not damaged.The production of tires and damping elements using these polyisoprenes.

Abstract: A polybutadiene having an average 1,2-bond content of 18 to 32% by mole, a branched polymer chain content of 60% by weight or more and a Mooney viscosity at 100.degree. C. of 40 to 90, the viscosity of a 5% by weight concentration solution of this polybutadiene in styrene at 25.degree. C. being 60 to 90 cps, and a process for preparing the polybutadiene comprising starting the polymerization of 1,3-butadiene in an inert hydrocarbon solvent in the presence of a Lewis basic compound and an organolithium compound, the latter compound being in an amount of 0.5 to 3 millimoles per 100 g of 1,3-butadiene, at a temperature selected from the range of 30.degree. to 80.degree. C., carrying out the polymerization by controlling the temperature so that the temperature at the end of polymerization may be 5.degree. to 40.degree. higher than the temperature at the start of polymerization, and adding to the resulting polymer solution a polyfunctional halogen compound in an amount of 0.

Abstract: It has been determined that 1,2,3-trialkoxybenzenes and 1,2,4-trialkoxybenzenes can be utilized in order to increase the vinyl content of polydienes which are prepared utilizing lithium catalyst systems. For instance, it has been determined that 1,2,3-trimethoxybenzene and 1,2,4-trimethoxybenzene are very strong modifiers for utilization in such polymerizations. The utilization of the trialkoxybenzene modifiers of the present invention is highly advantageous because they promote fast polymerization rates and can be used to produce polymers having high vinyl contents.

Abstract: A novel class of alloocimene polymers have been prepared which are comprised of a mixture of polymer chain units of 2,3-alloocimene and 6,7-alloocimene. The novel polyalloocimenes of this invention are prepared by polymerizing alloocimene in a reaction mixture which contains a catalyst system comprised of a metal such as sodium and an aliphatic or cycloaliphatic ether such as 1,2-dimethoxyethane. The polyalloocimenes of this invention have a majority of the residual unsaturation present in pendent dimethylbutadienyl groups. The polyalloocimenes of this invention are useful in of themselves as film forming binders for inks, as tackifiers for hot melt adhesive and the like. The polyalloocimenes of this invention are also especially useful as intermediates. The presence of the substantial amount of unsaturation and particularly the conjugated unsaturation of the pendent groups make the polyalloocimenes of this invention exceptionally reactive.

Abstract: A rubber composition for a tire tread comprising a novel modified styrene-butadiene copolymer rubber, carbon black, and aromatic oil.

Abstract: High solids acrylic coating compositions are formulated by using as a reactive diluent, a low molecular weight hydroxyl-containing acrylic polymer. These polymers are prepared at about 15.degree.-20.degree. C. with anionic initiator concentrations greater than about 5 mole percent.

Abstract: A process and a catalyst system is disclosed herein for preparation of medium to high vinyl (co)polymers containing a 1,2-microstructure of between 30 and about 90 percent. The catalyst system which is employed in the production of the (co)polymer is an oligomeric oxolanyl alkane modifier and anionic initiator selected from (1) Na(R).sub.3 Mg or (2) Na(R).sub.3 Mg and an organolithium compound or (3) K(R).sub.3 Mg and an organolithium compound.

Abstract: Conjugated dienes, in particular 1,3-conjugated dienes, can be polymerized or copolymerized using the catalyst system of this invention to polymers wherein the amount of 1,2-structure contained in the polymer is increased, and polymers can be prepared containing varying amounts of 1,2-structure as desired. Such desirable results can be obtained in accordance with the process of the present invention for polymerizing conjugated diene monomers which comprises the use of a catalyst system which comprises (a) at least one anionic initiator based on lithium, and (b) a modifier composition comprising at least one cyclic acetal of a glyoxal. ##STR1## wherein R and R' are each independently hydrogen, alkyl or aryl groups, and each A is independently an alkylene or an oxyalkylene group.In another embodiment, the catalyst system also contains at least one co-initiator selected from the group consisting of organomagnesium compounds, organoaluminum compounds, or mixtures thereof.

Abstract: The invention relates to elastomeric copolymers of an aromatic vinyl compound and a conjugated diene, suitable for use in the tread portion of a pneumatic tire, which copolymers have a vinyl content of at least 30% by weight and comprise at least two polymer chains coupled to one another having a differential content of the aromatic vinyl compound at the ends of the copolymer which changes in a portion of not more than 5% of each polymer chain from a first value to a second value which is at least 25 percentage points higher than the first value, and said portion lies within the free terminal 10% portion of the copolymer chain (as determined by monomer conversion); their preparation and their use in tread portions of tires. The process of the invention is characterized by employing as structure modifier a compound of formulaR.sup.1 --O--CH.sub.2 --CH.sub.2 --O--R.sup.2 (I)wherein R.sup.1 and R.sup.2 are the same or different C.sub.

Abstract: An optically active polymer is obtained by polymerizing a vinyl monomer in the presence of a catalyst which comprises an asymmetric ligand compound of the formula (I) or (II): ##STR1## in which R.sub.1 and R.sub.4 each are --O--R.sub.7, --S--R.sub.7, ##STR2## R.sub.2, R.sub.3, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 each are an alkyl group having 1 to 10 carbon atoms; X is hydrogen, an alkyl group having 1 to 10 carbon atoms or a halogen; and n is a number of 1 to 4; and an anionic initiator to form a complex with said ligand compound.

Abstract: Process for the preparation of polymers comprising conjugated dienes and optionally monoalkenyl aromatic hydrocarbons, which process comprises the polymerization of conjugated diene and optionally monoalkenyl aromatic hydrocarbon monomers in the presence of a hydrocarbon diluent, and a hydrocarbyl alkalimetal compound and a Lewis base having the formula ##STR1## wherein R.sub.1 is an alkyl group having 2-18 carbon atoms;R.sub.2 and R.sub.3 are hydrogen or an alkyl groups having 1-4 carbon atoms;R.sub.4 is hydrogen or an alkyl group having 1-6 carbon atoms; andR.sub.5 is an alkyl group having 1-18 carbon atoms.

Abstract: Conjugated dienes, in particular 1,3-conjugated dienes, can be polymerized or copolymerized using the catalyst system of this invention to polymers wherein the amount of 1,2-structure contained in the polymer is increased, and polymers can be prepared containing varying amounts of 1,2-structure as desired. Such desirable results can be obtained in accordance with the process of the present invention for polymerizing conjugated diene monomers which comprises the use of a catalyst system which comprises (a) at least one anionic initiator based on lithium, and (b) a modifier composition comprising at least one cyclic acetal of a glyoxal. ##STR1## wherein R and R' are each independently hydrogen, alkyl or aryl groups, and each A is independently an alkylene or an oxyalkylene group.In another embodiment, the catalyst system also contains at least one co-initiator selected from the group consisting of organomagnesium compounds, organoaluminum compounds, or mixtures thereof.

Abstract: It has been unexpectedly found that meta-diisopropenyl benzene can be polymerized into poly-m-diisopropenyl benzene with a relatively narrow molecular weight distribution and with only a small degree of crosslinking (gel formation) if done in the presence of at least one alpha-olefin containing from 2 to 12 carbon atoms in tetrahydrofuran (solvent) at low temperatures employing an alkyl lithium initiator. The poly-m-diisopropenyl benzene produced by employing this technique has an isopropenyl moiety on almost every diisopropenyl benzene repeat unit in the polymer. This polymer is particularly useful since its pendant isopropenyl groups can be further reacted with other compounds leading to polymers with various functionalities. This technique can also be employed in the synthesis of copolymers containing repeat units derived from meta-diisopropenyl benzene and one or more other monomers.

Abstract: An optically active polymer is obtained by polymerizing a vinyl monomer in the presence of a catalyst which comprises an asymmetric ligand compound of the formula (I) or (II): ##STR1## in which R.sub.1 and R.sub.4 each are ##STR2## R.sub.2, R.sub.3, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 each are an alkyl group having 1 to 10 carbon atoms; X is hydrogen, an alkyl group having 1 to 10 carbon atoms or a halogen; and n is a number of 1 to 4; and an anionic initiator to form a complex with said ligand compound.

Abstract: A process and catalyst system is disclosed herein for the preparation of (co)polymers having a 1,2-microstructure of between 20 and 95 percent. These (co)polymers are prepared in a hydrocarbon or other non-polar solvent from a monomer system which contains at least one 1,3-diene monomer. The catalyst system which is employed in the production of the (co)polymers of the present invention is a combination of (1) an anionic initiator based on lithium, and (2) a modifier compound selected from the group consisting of linear and cyclic oligomeric oxolanyl alkanes.

Abstract: A process and catalyst system is disclosed herein for the preparation of (co)polymers having a 1,2-microstructure of between 20 and 95 percent. These (co)polymers are prepared in a hydrocarbon or other non-polar solvent from a monomer system which contains at least one 1,3-diene monomer. The catalyst system which is employed in the production of the (co)polymers of the present invention is a combination of (1) an anionic initiator based on lithium; (2) an alkyl magnesium compound or an alkyl aluminum compound or a mixture thereof; and (3) a modifier compound selected from the group consisting of linear and cyclic oligomeric oxolanyl alkanes.

Abstract: A process for producing polymers of a conjugated diene, copolymers of a conjugated diene and another conjugated diene, or copolymers of conjugated diene and a vinyl aromatic hydrocarbon, which comprises polymerizing the corresponding monomers in the presence of a complex initiator consisting of components (a) and (b) described below, or (a) and (b) together with one or more components selected from components (c) and (d);(a) An organic compound of barium, strontium or calcium;(b) An organolithium-beryllium compound or an organolithiummagnesium compound;(c) An organolithium compound, an organoberyllium compound or an organomagnesium compound; and(d) An organoaluminum compound or an organozinc compound.The polymers of a conjugated diene containing relatively high trans-1,4 linkage, or the copolymers of a conjugated diene and a vinyl aromatic compound highly randomized and having high bound styrene and high trans-1,4 linkage can be produced at good yields.