摘要:
The subject invention discloses a pneumatic tire having an outer circumferential tread wherein said tread is a sulfur-cured rubber composition comprised of (a) an isoprene-butadiene diblock rubber, said isoprene-butadiene diblock rubber being comprised of a butadiene block and an isoprene-butadiene block, wherein said butadiene block has a number average molecular weight which is within the range of about 25,000 to about 350,000, wherein said isoprene-butadiene block has a number average molecular weight which is within the range of about 25,000 to about 350,000, wherein said isoprene-butadiene diblock rubber has essentially one glass transition temperature which is within the range of about -100.degree. C. to about -70.degree. C., wherein said isoprene-butadiene diblock polymer has a Mooney ML-4 viscosity at 100.degree. C. which is within the range of about 50 to about 140, and wherein the repeat units derived from isoprene and 1,3-butadiene in the isoprene-butadiene block are in essentially random order; and (b) a second rubber selected from the group consisting of high vinyl polybutadiene rubber, styrene-isoprene-butadiene rubber, solution styrene-butadiene rubber and emulsion styrene-butadiene rubber.
摘要:
The subject invention discloses a pneumatic tire having an outer circumferential tread wherein said tread is a sulfur-cured rubber composition comprised of (a) an isoprene-butadiene diblock rubber, said isoprene-butadiene diblock rubber being comprised of a butadiene block and an isoprene-butadiene block, wherein said butadiene block has a number average molecular weight which is within the range of about 25,000 to about 350,000, wherein said isoprene-butadiene block has a number average molecular weight which is within the range of about 25,000 to about 350,000, wherein said isoprene-butadiene diblock rubber has essentially one glass transition temperature which is within the range of about -100.degree. C. to about -70.degree. C., wherein said isoprene-butadiene diblock polymer has a Mooney ML-4 viscosity at 100.degree. C. which is within the range of about 50 to about 140, wherein the repeat units derived from isoprene and 1,3-butadiene in the isoprene-butadiene block are in essentially random order, and wherein said isoprene-butadiene diblock polymer does not contain any blocks which are derived solely from isoprene; and (b) a second rubber selected from the group consisting of high vinyl polybutadiene rubber, styrene-isoprene-butadiene rubber, solution styrene-butadiene rubber and emulsion styrene-butadiene rubber.
摘要:
This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend. Asymmetrical tin coupling in general also leads to better processability and other beneficial properties. This invention more specifically discloses a tire tread rubber composition which is comprised of (1) from about 20 phr to about 60 phr of tin-coupled polybutadiene rubber, (2) from about 20 phr to about 60 phr of a rubber selected from the group consisting of natural rubber and synthetic polyisoprene and (3) from about 5 phr to about 40 phr of high vinyl polybutadiene rubber.
摘要:
This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend. Asymmetrical tin coupling in general also leads to better processability and other beneficial properties. This invention more specifically discloses a tire tread rubber composition which is comprised of (1) from about 20 phr to about 60 phr of tin-coupled polybutadiene rubber, (2) from about 20 phr to about 60 phr of a rubber selected from the group consisting of natural rubber and synthetic polyisoprene and (3) from about 5 phr to about 40 phr of high vinyl polybutadiene rubber.
摘要:
This invention reveals a process for preparing high vinyl polybutadiene rubber which comprises polymerizing 1,3-butadiene monomer with a lithium initiator at a temperature which is within the range of about 5.degree. C. to about 100.degree. in the presence of a sodium alkoxide and 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 0.05:1 to about 10:1.
摘要:
This invention relates to a tire tread compound that is easily processable which can be used to improve the treadwear, rolling resistance and traction characteristics of tires. The tire tread compounds of this invention are a blend of tin-coupled polybutadiene, high vinyl polybutadiene and natural rubber. This blend of low glass transition temperature rubber and high glass transition temperature rubber is surprisingly easy to process which makes the concept of this invention commercially feasible. Thus, the tire tread compounds of this invention can be utilized in making tires having greatly improved traction characteristics and treadwear without sacrificing rolling resistance. These improved properties may be due, in part, to better interaction and compatibility with carbon black and/or silica fillers. The polybutadiene in the blend can be asymmetrical tin-coupled to further improve the cold flow characteristics of the rubber blend. Asymmetrical tin coupling in general also leads to better processability and other beneficial properties. This invention more specifically discloses a tire tread rubber composition which is comprised of (1) from about 20 phr to about 60 phr of tin-coupled polybutadiene rubber, (2) from about 20 phr to about 60 phr of a rubber selected from the group consisting of natural rubber and synthetic polyisoprene and (3) from about 5 phr to about 40 phr of high vinyl polybutadiene rubber.
摘要:
The present invention is directed to a catalyst system for synthesizing rubbery polymers, such as polybutadiene rubber, styrene-butadiene rubber, isoprene-butadiene rubber, or styrene-isoprene-butadiene rubber, that are amine functionalized and have a high trans microstructure. The catalyst system, in one embodiment, includes (a) an organolithium amine compound, (b) a group IIa metal salt of an amino glycol or a glycol ether, (c) an organoaluminum compound, and optionally (d) an amine compound. The amine functionalized rubbery polymers can be utilized in tire tread rubbers where the rubbery polymers may provide desirable wear properties without substantially sacrificing other performance characteristic(s), e.g., traction properties.
摘要:
The process and catalyst of this invention can be utilized to synthesize homo and copolymers of conjugated diene monomers and vinyl aromatic monomers having high trans contents of greater than 60% with low melting points. These homo and copolymers of conjugated diene monomers and vinyl aromatic monomers can be utilized in tire tread and sidewall rubbers that exhibit outstanding wear and tear characteristics in the tread and excellent flexing properties in the sidewall. The rubber polymers of this invention are made utilizing an improved catalyst system. This catalyst system is comprised of (a) organo aluminum compounds, (b) organo lithium compounds, (c) a barium compound selected from barium salts of (i) di(ethylene glycol) ethyl ether, (ii) di(ethylene glycol) propyl ether, (iii) di(ethylene glycol) hexyl ether, (iv) di(N,N-dimethyl amino glycol) ethyl ether, (v) menthol and thymol in the presence of polar modifier consisting of water, alcohols, amines, thiols, phosphates and phosphites. The trans polymers and copolymers of this invention made with the above catalyst system typically have a glass transition temperature ranging from −97° C. to −40° C., a melt temperature ranging from −30° C. to +30° C., and a number average molecular weight from 20,000 to 250,000. The inclusion of such polar modifiers in the barium catalyst system results in a high styrene content in copolymerization, a high trans content, and high molecular weight. Copolymers of conjugated diolefin monomers and vinyl aromatic monomers made with the catalyst system of this invention also have a tapered macrostructure.
摘要:
The subject invention relates to a technique for synthesizing rubbery copolymers of styrene and butadiene and/or isoprene. These rubbers exhibit an excellent combination of properties for utilization in high performance tire tread rubber compounds. The subject invention specifically discloses a process for preparing a styrene-butadiene rubber (SBR) which comprises: copolymerizing from about 30 weight percent to about 55 weight percent styrene and from about 45 weight percent to about 70 weight percent 1,3-butadiene in an alkane solvent, such as hexane, at a temperature which is within the range of about -10.degree. C. to about 150.degree. C. in the presence of (a) an alkali metal alkoxide, and (b) an organolithium compound, wherein the molar ratio of the alkali metal alkoxide to the organolithium compound is within the range of about 0.01:1 to about 1:1. The subject invention further discloses a process for preparing a rubbery copolymer of styrene and isoprene having an excellent combination of properties for use in making tire treads by a solution polymerization process which comprises: copolymerizing from about 30 weight percent to about 55 weight percent styrene and from about 45 weight percent to about 70 weight percent isoprene in an alkane solvent at a temperature which is within the range of about -10.degree. C. to about 150.degree. C. in the presence of (a) an alkali metal alkoxide, and (b) an organolithium compound, wherein the molar ratio of the alkali metal alkoxide to the organolithium compound is within the range of about 0.01:1 to about 1:1.
摘要:
The present invention is directed to a catalyst system for synthesizing rubbery polymers, such as polybutadiene rubber, styrene-butadiene rubber, isoprene-butadiene rubber, or styrene-isoprene-butadiene rubber, that are amine functionalized and have a high trans microstructure. The catalyst system, in one embodiment, includes (a) an organolithium amine compound, (b) a group IIa metal salt of an amino glycol or a glycol ether, (c) an organoaluminum compound, and optionally (d) an amine compound. The amine functionalized rubbery polymers can be utilized in tire tread rubbers where the rubbery polymers may provide desirable wear properties without substantially sacrificing other performance characteristic(s), e.g., traction properties.