摘要:
The process of this invention can be utilized to improve the adhesion between rubber components. It is generally most useful for improving the adhesion between two different pre-cured rubber components or for improving the adhesion between a pre-cured rubber component and an uncured (green) rubber component. However, the technique of this invention can also be employed to improve the adhesion between two uncured rubber components. The technique of this invention is based upon the unexpected discovery that low molecular weight trans-1,4-polybutadiene containing rubber compounds can be used to improve the adhesion between rubber components. This invention more specifically reveals a technique for improving the adhesion between a first rubber component and a second rubber component in a process for manufacturing a cured rubber article, said technique comprising the steps of: (1) positioning a layer of an adhesion-promoting rubber composition which is comprised of a low molecular weight trans-1,4-polybutadiene rubber between the first rubber component and the second rubber component, (2) bringing the first rubber component into contact with one side of the layer of adhesion-promoting rubber composition and bringing the second rubber composition into contact with the other side of the layer of adhesion-promoting rubber composition and (3) curing the first rubber composition, the second rubber composition and the adhesion-promoting rubber composition together under conditions of heat and pressure to produce the cured rubber article.
摘要:
This invention discloses a process for making dilithium initiators in high purity. This process can be conducted in the absence of amines which is desirable since amines can act as modifiers for anionic polymerizations. The dilithium compounds made are highly desirable because they are soluble in aromatic solvents. The present invention more specifically discloses a process for synthesizing a dilithium initiator which comprises reacting diisopropenylbenzene with a tertiary alkyl lithium compound in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. The present invention further discloses a process for synthesizing m-di-(1-lithio-1-methyl-3,3-dimethylbutyl)benzene which comprises reacting diisopropenylbenzene with tertiary-butyllithium in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. The present invention also discloses a process for synthesizing a functionalized lithium initiator which comprises reacting a dilithium initiator with a alkylaminoaryl compound of the structural formula: wherein R, R′, and R″ can be the same or different, wherein R is selected from the group consisting of hydrogen atoms, alkyl groups, aryl groups, alkaryl groups, and amino aryl groups, and wherein R′ and R″ represent alkyl groups.
摘要:
The present invention relates to an anionic polymerization technique for synthesizing functionalized rubbery polymers containing polysiloxane that have excellent characteristics for utilization in (a) tire tread compounds that are highly loaded with silica, (b) shiny tire side-wall compounds, and (c) tire building bladders having improved mold release characteristics. The rubbery polymers of this invention can optionally be coupled with tin halides or silicon halides to further improve the characteristics of the rubber for use in tire tread compounds. The present invention more specifically discloses a process for synthesizing a rubbery polymer that comprises (1) polymerizing at least one conjugated diolefin monomer to produce a living rubbery polymer, wherein said polymerization is optionally carried out in the presence of a polar modifier, wherein said polymerization is an anionic polymerization that is initiated with an alkylsilyloxy protected functional lithium initiator having a structural formula selected from the group consisting: wherein X represents a group IVa element selected from the group consisting of carbon, silicon, germanium, and tin, wherein Y represents phosphorous or nitrogen, wherein R represents alkyl groups that can be the same or different, wherein the alkyl groups contain from 1 to about 8 carbon atoms, and wherein A represents an alkylene group containing from 1 to about 8 carbon atoms; (2) adding a hexaalkylcyclotrisiloxane monomer to the living rubbery polymer; (3) allowing the hexaalkylcyclotrisiloxane monomer to polymerize to produce a living polysiloxane containing rubber; and optionally, (4) reacting the living polysiloxane containing rubber with a coupling agent selected from the group consisting of tin halides and silicon halides to produce a coupled polysiloxane containing rubber.
摘要:
This invention discloses a process for making dilithium initiators in high purity. This process can be conducted in the absence of amines which is desirable since amines can act as modifiers for anionic polymerizations. The dilithium compounds made are highly desirable because they are soluble in aromatic solvents. The present invention more specifically discloses a process for synthesizing a dilithium initiator which comprises reacting disopropenylbenzene with a tertiary alkyl lithium compound in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. The present invention further discloses a process for synthesizing m-di-(1-methyl-3,3-dimethylbutyllithio)benzene which comprises reacting diisopropenylbenzene with tertiary-butyllithium in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. The present invention also discloses a process for synthesizing a functionalized lithium initiator which comprises the steps of (1) reacting diisopropenylbenzene with a tertiary alkyl lithium compound in an aromatic solvent at a temperature which is within the range of about 0° C. to about 100° C. to produce a dilithium initiator; and (2) reacting the dilithium initiator with a halide compound selected from the group consisting of (a) tin halides, (b) silicon halides, (c) amine halides, and (d) phosphorus halides of the structural formula: wherein X represents a halogen atom, and wherein R1, R2, and R3 represent alkyl groups, aryl groups, and/or alkoxy groups containing from 1 to about 10 carbon atoms.
摘要:
The process of this invention can be utilized to stabilize tin-coupled rubbery polymers. This process involves adding a chelating diamine or a sodium alkoxide to the rubbery polymer after the tin coupling has been carried out. This invention more specifically discloses a process for improving the stability of a tin-coupled rubbery polymer which comprises adding a sodium alkoxide to the tin-coupled rubbery polymer subsequent to the time at which the tin-coupled rubbery polymer is coupled. Sodium alkoxide is a representative example of a sodium alkoxide that can be used to stabilize the tin-coupled rubbery polymer.
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:
Tire rubbers which are prepared by anionic polymerization are frequently coupled with a suitable coupling agent, such as a tin halide, to improve desired properties. It has been unexpectedly found that greatly improved properties for tire rubbers, such as lower hysteresis, can be attained by asymmetrically coupling the rubber. This invention more specifically discloses an asymmetrical tin-coupled rubbery polymer which is particularly valuable for use in manufacturing tire tread compounds, said asymmetrical tin-coupled rubbery polymer being comprised of a tin atom having at least three polydiene arms covalently bonded thereto, wherein at least one of said polydiene arms has a number average molecular weight of less than about 40,000, wherein at least one of said polydiene arms has a number average molecular weight of at least about 80,000, and wherein the ratio of the weight average molecular weight to the number average molecular weight of the asymmetrical tin-coupled rubbery polymer is within the range of about 2 to about 2.5.
摘要:
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 metallated rubbery polymer and the silicon containing compound is conducted 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 diamines.
摘要:
This invention relates to a precipitated silica reinforced conjugated diene-based elastomer composition containing an alkoxysilane coupled, in-chain functionalized, conjugated diene-based elastomer and to a tire having at least one component thereof. Said in-chain functionalized conjugated diene-based elastomer is a conjugated diene-based elastomer which contains a plurality of at least one of in-chain p- and m-(2-pyrrolidinoethyl) styrene (PES) and m-(2-pyrrolidino-1-methylethyl) alpha-methylstyrene (PAMS) groups.
摘要:
This invention discloses a process for synthesizing a dendrimer of a rubbery polymer comprising: (a) reacting a lithium terminated rubbery polymer with a halogenated tin containing compound to produce a polymer which is terminated with halogenated tin moieties, wherein the halogenated tin containing compound is of the structural formula: wherein X represents a halogen atom, wherein Z1 groups can be the same or different and are selected from alkyl groups containing from 1 to 8 carbon atoms, wherein x represents an integer from 1 to 20, wherein the molar ratio of the lithium terminated rubbery polymer to halogen atoms in the halogenated tin containing compound is within the range of 2:n to (n−1):n, wherein n represents the number of halogen atoms that are bonded directly to tin atoms in the halogenated tin containing compound; (b) reacting the polymer which is terminated with halogenated tin moieties with a molar excess of a tertiary alcohol to produce a polymer which is terminated with hydroxy tin moieties; and (c) allowing the polymer which is terminated with the hydroxy tin moieties to couple under conditions sufficient to produce a dendrimer of the rubbery polymer.