Abstract: A pneumatic rubber tire having a rubber sidewall composition containing trans 1,4-polybutadiene rubber and at least one additional 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 invention relates to a tire with a tread which is quantitatively reinforced with silica where the tread is composed of cis 1,4-polybutadiene rubber, a high vinyl polybutadiene rubber and, optionally a medium vinyl polybutadiene rubber. In one aspect, the tread rubber can also contain a minor amount of cis 1,4-polyisoprene natural rubber.

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 present invention relates to a rubber composition containing silica reinforcement and to pneumatic tires having treads comprised of such rubber composition.A rubber composition comprises at least one elastomer, silica, carbon black and a silica coupler comprised of poly-(2-propanol-1,3-polysulfide).

Abstract: The present invention relates to a rubber composition containing silica reinforcement and to pneumatic tires having treads comprised of such rubber composition.A rubber composition comprises at least one elastomer, silica, carbon black and a silica coupler comprised of 3,3'-tetrathiodipropionitrile polysulfide mixture.

Abstract: Disclosed are expandable bladders for use in curing presses for rubber compositions such as pneumatic tires. The bladders are a crosslinked elastomer comprising an isobutylene rubbery polymer. The bladder composition includes corn oil which improves the release characteristics of the cured bladder from a tire innerliner cured in contact with said bladder. The improved release characteristics have been observed to allow rubber compositions such as tires to be molded with fewer defects caused during release of the bladder from the tires or caused by abraded or deformed bladders. The use of corn oil also has been observed to increase the useful life time of the bladder allowing more tires to be cured without changing bladders. A preferred isobutylene rubbery polymer is a brominated copolymer of isobutylene and p-methylstyrene. The bladder compositions have also been observed to have an enhanced flexibility due to the corn oil.

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: Expandable bladders for use in curing presses for hydrocarbon rubbers such as pneumatic tires are a crosslink elastomer comprising isobutylene repeat units and include graphite. A preferred isobutylene elastomer is a brominated copolymer of isobutylene and p-methylstyrene. The bladders have enhanced lubricity, low adhesion to tire innerliners, and lower hot tension set. The above enhancements allow hydrocarbon rubbers such as tires to be molded with fewer defects caused by abraded or deformed bladders. They also enhance the useful life of the bladder reducing the cost of tire curing.

Abstract: A rubber composition comprised of elastomer, silica, a silica coupler, sulfur and, optionally, carbon black, in which the silica, silica coupler and at least a portion of the sulfur are added in a non-productive mix stage.Pneumatic tires having treads comprised of such rubber composition are provided.

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 present invention relates to a silica reinforced rubber composition and pneumatic tires having treads comprised of the silica reinforced rubber compositions. The silica reinforced rubber composition comprises an elastomer, silica, optionally carbon black and a silica coupler comprised of the zinc salt, the ammonium salt or the sodium salt of salicylic acid.

Abstract: A rubber composition comprised of elastomer, silica, a silica coupler, 2-mercaptobenzothiazole and, optionally, carbon black, in which the silica, silica coupler and at least a portion of the 2-mercaptobenzothiazole are added in a non-productive mix stage.Pneumatic tires having treads comprised of such rubber composition are provided.

Abstract: Pneumatic rubber tire with a tread composed of a rubber blend of a base of at least two synthetic elastomers composed of (i) specialized isoprene/butadiene copolymer elastomer having a low Tg in a range of about -70.degree. to about -100.degree. C. and (ii) a diene based elastomer having a Tg in a range of about -5.degree. to about -30.degree. C. together with a minor amount of natural cis 1,4-polyisoprene rubber. Selection of the base of the said two synthetic elastomers having spaced apart, or spatially defined, Tg's of at least 40.degree. C. is an important feature of the tread rubber blend. Representative examples of contemplated elastomers with Tg's in a range of about -5.degree. to about -30.degree. C. are 3,4-polyisoprene elastomer, styrene/isoprene copolymer elastomer and high vinyl polybutadiene elastomers.In one aspect, the tread rubber blend is reinforced with reinforcing filler composed of carbon black or a combination of carbon black and silica accompanied by a coupling agent.

Abstract: The present invention relates to a rubber composition containing silica reinforcement and to pneumatic tires having treads comprised of such rubber composition.A rubber composition comprises at least one elastomer, silica, carbon black and a silica coupler comprised of nicotinamide.

Abstract: The present invention relates to a composition which exhibits antiozonant activity in diene containing rubbers comprising the reaction product of a multi-step process comprising:(1) reacting under condensation conditions an aldehyde and an amine containing compound to form a condensation product, whereinsaid aldehyde is selected from the group consisting of formaldehyde, acetaldehyde or mixtures thereof; andsaid amine containing compound is selected from the group consisting of: N,N'-di-substituted-p-phenylene diamines of the structural formula: ##STR1## wherein R.sup.1 and R.sup.2 are independently selected from the group of radicals consisting of alkyls having 3 to 12 carbon atoms, aryls having 6 to 12 carbon atoms and aralkyls having 7 to 12 carbon atoms; and wherein said condensation conditions include:(i) the presence of an acid catalyst,(ii) a mole ratio of aldehyde to amine containing compound ranging from about 1.

Abstract: The present invention relates to monoesters of rosin acids which are useful as a total or partial replacement for extender or processing oil in rubber formulations. Addition of these monoesters of rosin acid improve the modulus and tear of the vulcanizate. The monoesters are of the formula: ##STR1## wherein R.sup.1 and R.sup.2 are the same or different hydrocarbon radicals selected from the group consisting of saturated alkyl and cycloalkyl radicals containing 3 to 20 carbon atoms, aryl radicals containing 6 carbon atoms and aralkyl radicals containing 7 to 20 carbon atoms.

Abstract: A pneumatic tire having a sulfur cured rubber composition as a circumferential tread. The sulfur cured rubber composition is composed of, based on 100 parts by weight of rubber, from about 1.0 to 15 parts by weight of epoxidized rubber; from about 1.0 to 15 parts by weight of a carboxylated nitrile rubber; and 98 to 70 parts by weight of a rubber selected from the group consisting of medium vinyl polybutadiene, styrene-butadiene rubber, synthetic cis-1,4-polyisoprene, synthetic 3,4-polyisoprene, natural rubber, cis-polybutadiene, styrene-isoprene rubber, styrene-isoprene-butadiene rubber, acrylonitrile-butadiene rubber and mixtures thereof. The sulfur cured rubber composition is further composed of a silica filler and a silica coupling agent.

Abstract: The present invention relates to a sulfur cured rubber composition particularly suited for use in tire treads. The sulfur cured rubber composition is composed of, based on 100 parts by weight of rubber, from about 1.0 to 15 parts by weight of epoxidized rubber; from about 1.0 to 15 parts by weight of a carboxylated nitrile rubber; and 98 to 70 parts by weight of a rubber selected from the group consisting of medium vinyl polybutadiene, styrene-butadiene rubber, synthetic cis-1,4-polyisoprene, synthetic 3,4-polyisoprene, natural rubber, cis-polybutadiene, styrene-isoprene rubber, styrene-isoprene-butadiene rubber, acrylonitrile-butadiene rubber and mixtures thereof. The sulfur cured rubber composition is further composed of a silica filler and a silica coupling agent.

Abstract: The present invention relates to a sulfur cured rubber composition particularly suited for use in tire treads. The sulfur cured rubber composition is composed of based on 100 parts by weight of rubber, from about 1.0 to 15 parts by weight of epoxidized rubber; from about 1.0 to 15 parts by weight of a carboxylated nitrile rubber; and 98 to 70 parts by weight of a rubber selected from the group consisting of medium vinyl polybutadiene, styrene-butadiene rubber, synthetic cis-1,4-polyisoprene, synthetic 3,4-polyisoprene, natural rubber, cis-polybutadiene, styrene-isoprene rubber, styrene-isoprene-butadiene rubber, acrylonitrile-butadiene rubber and mixtures thereof.