Abstract: The subject invention discloses a process for modifying a rubbery polymer to improve silica interaction which comprises the steps of: (1) metallating the rubbery polymer with lithium by reacting the rubbery polymer with an organo lithium compound in the presence of a member selected from the group consisting of alkali metal alkoxides, alkali metal phenoxides and chelating tertiary alkyl 1,2- ethylene dieumines to produce a metallated rubbery polymer; and (2) reacting the metallated rubbery polymer with a silicon containing compound to produce the modified rubbery polymer having improved silica interaction, wherein the silicon containing compound is selected from the group consisting of silanes and siloxanes, wherein said silanes and siloxanes contain at least two functional groups which can be the same or different and which are selected from the group consisting of alkoxy groups, tertiary amino groups, cyano groups, sulfonyl groups, epoxy groups and halogen atoms; and wherein the reaction between the metalla

Abstract: This invention reveals a pneumatic tire having an outer circumferential tread wherein said tread is a sulfur-cured rubber composition comprised of, based on 100 parts by weight of rubber, (1) from about 5 to about 50 parts of 3,4-polyisoprene rubber, wherein said 3,4-polyisoprene rubber has (a) a 3,4-isomer content of from 75 percent to 95 percent, (b) a 1,2-isomer content of from 5 percent to 25 percent, (c) a glass transition temperature from 0.degree. to 25.degree. C. and (d) a number average molecular weight which is within the range of 30,000 to 180,000; and (2) from about 50 to about 95 parts of a rubbery polymer which is co-curable with the 3,4-polyisoprene rubber.

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 subject invention discloses a process for preparing a coupled styrene-isoprene-butadiene rubber which is particularly valuable for use in making automobile tire tread rubber compounds which comprises the steps of (1) solution terpolymerizing in an organic solvent from about 5 weight percent to about 40 weight percent styrene, from about 1 weight percent to about 10 weight percent isoprene, and from about 50 weight percent to about 94 weight percent 1,3-butadiene, based on total monomers, to a conversion of at least about 90% to produce a living styrene-isoprene-butadiene polymer, wherein the terpolymerization is initiated with an organolithium compound, and wherein the terpolymerization is conducted in the presence of a polar modifier at a molar ratio of the polar modifier to the organolithium compound, which is within the range of about 0.5:1 to about 5:1, and wherein the terpolymerization is conducted at a temperature which is within the range of about 20.degree. C. to about 150.degree. C.

Abstract: The subject invention discloses an isoprene-butadiene diblock rubber which is particularly valuable for use in making treads for tires which have improved wear characteristics without compromising traction characteristics or rolling resistance. Said isoprene-butadiene diblock rubber is comprised of (1) a first block which is comprised of repeat units which are derived from 1,3-butadiene and (2) a second block which is comprised of repeat units which are derived from both 1,3-butadiene and isoprene, wherein the repeat units derived from isoprene and 1,3-butadiene in the second block are in an essentially random order, wherein the diblock rubber has a glass transition temperature which is within the range of about -100.degree. C. to about -70.degree. C., and wherein the diblock rubber has a Mooney viscosity which is within the range of about 50 to about 140.

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: The subject invention discloses a process for preparing a coupled styrene-isoprene-butadiene rubber which is particularly valuable for use in making automobile tire tread rubber compounds which comprises the steps of (1) solution terpolymerizing in an organic solvent from about 5 weight percent to about 40 weight percent styrene, from about 1 weight percent to about 10 weight percent isoprene, and from about 50 weight percent to about 94 weight percent 1,3-butadiene, based on total monomers, to a conversion of at least about 90% to produce a living styrene-isoprene-butadiene polymer, wherein the terpolymerization is initiated with an organolithium compound, and wherein the terpolymerization is conducted in the presence of a polar modifier at a molar ratio of the polar modifier to the organolithium compound, which is within the range of about 0.5:1 to about 5:1, and wherein the terpolymerization is conducted at a temperature which is within the range of about 20.degree. C. to about 150.degree. C.

Abstract: This invention reveals a high performance polybutadiene rubber blend comprised of (a) a first polybutadiene rubber, (b) a second polybutadiene rubber, and (c) a third polybutadiene rubber; wherein the first polybutadiene rubber, the second polybutadiene rubber, and the third polybutadiene rubber are selected from the group of consisting of super-high vinyl polybutadiene rubbers having a vinyl content which is within the range of 80 percent to 100 percent, high vinyl polybutadiene rubbers having a vinyl content which is within the range of 60 percent to 79 percent, medium vinyl polybutadiene rubbers having a vinyl content which is within the range of 35 percent to 59 percent, and low vinyl polybutadiene rubbers having a vinyl content which is within the range of 8 percent to 34 percent; wherein at least three members selected from the group consisting of super-high vinyl polybutadiene rubbers, high vinyl polybutadiene rubbers, medium vinyl polybutadiene rubbers, and low vinyl polybutadiene rubbers are included

Abstract: The subject invention discloses a process for preparing a coupled styrene-isoprene-butadiene rubber which is particularly valuable for use in making automobile tire tread rubber compounds which comprises the steps of (1) solution terpolymerizing in an organic solvent from about 5 weight percent to about 40 weight percent styrene, from about 1 weight percent to about 10 weight percent isoprene, and from about 50 weight percent to about 94 weight percent 1,3-butadiene, based on total monomers, to a conversion of at least about 90% to produce a living styrene-isoprene-butadiene polymer, wherein the terpolymerization is initiated with an organolithium compound, and wherein the terpolymerization is conducted in the presence of a polar modifier at a molar ratio of the polar modifier to the organolithium compound, which is within the range of about 0.5:1 to about 5:1, and wherein the terpolymerization is conducted at a temperature which is within the range of about 20.degree. C. to about 150.degree. C.

Abstract: The subject invention discloses a process for preparing a coupled styrene-isoprene-butadiene rubber which is particularly valuable for use in making automobile tire tread rubber compounds which comprises the steps of (1) solution terpolymerizing in an organic solvent from about 5 weight percent to about 40 weight percent styrene, from about 1 weight percent to about 10 weight percent isoprene, and from about 50 weight percent to about 94 weight percent 1,3-butadiene, based on total monomers, to a conversion of at least about 90% to produce a living styrene-isoprene-butadiene polymer, wherein the terpolymerization is initiated with an organolithium compound, and wherein the terpolymerization is conducted in the presence of a polar modifier at a molar ratio of the polar modifier to the organolithium compound, which is within the range of about 0.5:1 to about 5:1, and wherein the terpolymerization is conducted at a temperature which is within the range of about 20.degree. C. to about 150.degree. C.

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: The subject invention discloses a process for preparing a coupled styrene-isoprene-butadiene rubber which is particularly valuable for use in making automobile tire tread rubber compounds which comprises the steps of (1) solution terpolymerizing in an organic solvent from about 5 weight percent to about 40 weight percent styrene, from about 1 weight percent to about 10 weight percent isoprene, and from about 50 weight percent to about 94 weight percent 1,3-butadiene, based on total monomers, to a conversion of at least about 90% to produce a living styrene-isoprene-butadiene polymer, wherein the terpolymerization is initiated with an organolithium compound, and wherein the terpolymerization is conducted in the presence of a polar modifier at a molar ratio of the polar modifier to the organolithium compound, which is within the range of about 0.5:1 to about 5:1, and wherein the terpolymerization is conducted at a temperature which is within the range of about 20.degree. C. to about 150.degree. C.

Abstract: The subject invention discloses an isoprenebutadiene rubber which is particularly valuable for use in making truck tire treads, said rubber being comprised of repeat units which are derived from about 20 weight percent to about 50 weight percent isoprene and from about 50 weight percent to about 80 weight percent 1,3-butadiene, wherein the repeat units derived from isoprene and 1,3-butadiene are in essentially random order, wherein from about 3% to about 10% of the repeat units in said rubber are 1,2-polybutadiene units, wherein from about 50% to about 70% of the repeat units in said rubber are 1,4-polybutadiene units, wherein from about 1% to about 4% of the repeat units in said rubber are 3,4-polyisoprene units, wherein from about 25% to about 40% of the repeat units in the polymer are 1,4-polyisoprene units, wherein the rubber has a glass transition temperature which is within the range of about -90.degree. C. to about -75.degree. C.

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: Strain crystallizable 3,4-polyisoprene having a 3,4-microstructure content which is within the range of about 65% to about 85%, a cis-1,4-microstructure content which is within the range of about 15% to about 35%, and essentially no trans-1,4-microstructure or 1,2-microstructure can be synthesized in organic solvents to quantitative yields after short polymerization times by utilizing the catalyst systems of this invention. This invention specifically discloses a process for the synthesis of 3,4-polyisoprene which comprises polymerizing isoprene monomer in an organic solvent at a temperatIre which is within the range of about -10.degree. C. to about 100.degree. C.

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: It is desirable to increase the modulus of rubbers utilized in a wide variety of applications. This invention discloses a technique for preparing high modulus rubber compositions. By utilizing this technique, high modulus can be attained without sacrificing other properties, such as hysteresis. The subject invention more specifically relates to a process for preparing a high modulus rubber composition which comprises: (1) polymerizing at least one diisocyanate with at least one member selected from the group consisting of diols and diamines in a polymer cement of a rubbery elastomer under conditions which result in the formation of a rubber cement having the crystalline polymer dispersed therein; and (2) recovering the high modulus rubber composition from the rubber cement.

Abstract: The subject invention discloses a styrene-isoprene-butadiene rubber which is particularly valuable for use in making truck tire treads, said rubber being comprised of repeat units which are derived from about 5 weight percent to about 20 weight percent styrene, from about 7 weight percent to about 35 weight percent isoprene, and from about 55 weight percent to about 88 weight percent 1,3-butadiene, wherein the repeat units derived from styrene, isoprene and 1,3-butadiene are in essentially random order, wherein from about 25% to about 40% of the repeat units derived from the 1,3-butadiene are of the cis-microstructure, wherein from about 40% to about 60% of the repeat units derived from the 1,3-butadiene are of the trans-microstructure, wherein from about 5% to about 25% of the repeat units derived from the 1,3-butadiene are of the vinyl-microstructure, wherein from about 75% to about 90% of the repeat units derived from the isoprene are of the 1,4-microstructure, wherein from about 10% to about 25% of the re

Abstract: The subject invention discloses a pneumatic rubber tire comprised of a toroidal shaped fabric-reinforced rubber carcass and an outer circumferential rubber tread, two spaced substantially inextensible beads and two sidewalls extending radially from and connecting said tread to said beads, said tire characterized by having a circumferential fabric reinforced rubber belt positioned between said tread and supporting carcass where the rubber of said belt is comprised of (A) from about 25 to about 75 weight percent of a highly dispersed blend of syndiotactic 1,2-polybutadiene in synthetic polyisoprene, (B) from about 25 to about 75 weight percent natural rubber, and (C) from 0 to about 40 weight percent polydiene rubbers other than natural rubber. The present invention also reveals the utilization of syndiotactic 1,2-polybutadiene containing rubber compounds in and around the edges of the belt plies as a gum layer and in undertread gum layers.