The Goodyear & Tire Rubber Company

Michael Leslie Senyek

Howard Allen Colvin

Joginder Lal

Paul Harry Sandstrom

Dane Kenton Parker

Edward John Blok

David John Zanzig

Martin Paul Cohen

Lewis Timothy Lukich

Joseph John Kulig

William Paul Francik

Eilert A Ofstead

Xiaoping Yang

Steven Wayne Cronin

Cigdem Gurer

Mitchell S Kolaczewski

Albert J Costanza

This invention relates to preparation of nanocomposites comprised of elastomer and a dispersion of an at least partially exfoliated water swellable clay and to rubber compositions containing such nanocomposite and articles of manufacture which contain at least one component thereof. The nanocomposite is prepared by addition of a water suspension of water swellable clay particles to an anionic aqueous emulsion of elastomer particles to form a mixture to which an amine having at least two amine centers is added to intercalate and at least partially exfoliate the water swelled clay particles by an ion exchange within the galleries of the multilayered clay with cation exchangeable ion(s) and to aid in coagulating the elastomer and resultant clay particles to form said nanocomposite.

Preparation of nanocomposite of elastomer and exfoliated clay platelets, rubber compositions comprised of said nanocomposite and articles of manufacture, including tires

This invention discloses an emulsion styrene-butadiene rubber (SBR) that can be employed in manufacturing tire tread formulations that have rolling resistance and treadwear characteristics that are similar to those made with solution SBR but with improved traction characteristics. Thus, the emulsion SBR of this invention is superior in many respects for use in tire tread compounds to conventional solution SBR and conventional emulsion SBR. This invention more specifically discloses a styrene-butadiene rubber composition which is comprised of repeat units which are derived from styrene, 1,3-butadiene, and a hydroxy alkyl acrylate monomer, wherein the styrene-butadiene rubber composition has a number average molecular weight as determined by field flow fractionation which is within the range of about 50,000 to 150,000, and wherein the styrene-butadiene rubber has a light scattering to refractive index ratio which is within the range of 1.8 to 3.9. The subject invention further reveals a styrene-butadiene rubber composition which is comprised of repeat units which are derived from styrene, 1,3-butadiene, and a hydroxy alkyl acrylate monomer, wherein a plot of log frequency versus elastic modulus of the styrene-butadiene rubber composition crosses over a plot of log frequency versus loss modulus of the styrene-butadiene rubber composition at a frequency within the range of 0.001 radians per second to 100 radians per second when conducted at 120&deg; C. using parallel plate geometry in the dynamic oscillation frequency sweep of the styrene-butadiene rubber. The hydroxy alkyl acrylate monomer is preferably hydroxypropylmethacrylate.

Emulsion styrene-butadiene rubber

This invention discloses an emulsion styrene-butadiene rubber (SBR) that can be employed in manufacturing tire tread formulations that have rolling resistance and treadwear characteristics that are similar to those made with solution SBR but with improved traction characteristics. Thus, the emulsion SBR of this invention is superior in many respects for use in tire tread compounds to conventional solution SBR and conventional emulsion SBR. This invention more specifically discloses a styrene-butadiene rubber composition which is comprised of repeat units which are derived from styrene and 1,3-butadiene, wherein the styrene-butadiene rubber composition has a number average molecular weight as determined by thermal field flow fractionation which is within the range of about 50,000 to 150,000, and wherein the styrene-butadiene rubber has a light scattering to refractive index ratio which is within the range of 1.8 to 3.9. The subject invention further reveals a styrene-butadiene rubber composition which is comprised of repeat units which are derived from styrene and 1,3-butadiene, wherein a plot of log frequency versus storage modulus of the styrene-butadiene rubber composition crosses over a plot of log frequency versus loss modulus of the styrene-butadiene rubber composition at a log frequency within the range of 0.001 radians per second to 100 radians per second when conducted at 120&deg; C. using parallel plate geometry in the dynamic oscillation frequency sweep of the styrene-butadiene rubber.

Mercaptans are normally used as chain transfer agents in emulsion polymerizations. The mercaptans used in commercial applications are typically complex mixtures of hundreds of similar compounds having boiling points within a narrow range. The chain transfer activity of different mercaptans with such mixtures can vary substantially. To further complicate the situation, the distribution of various mercaptans can also vary substantially between lots of material obtained from commercial sources. Thus, consistent molecular weight control is typically difficult to attain in free radical emulsion polymerizations. This invention is based upon the unexpected discovery that dibenzyltrithiocarbonate will act as a pure compound to effectively and consistently control molecular weight in free radical emulsion polymerizations. The polydispersity of polymers made using dibenzyltrithiocarbonate as a molecular weight regulator is similar to that obtained using conventional mercaptan systems. This invention more specifically discloses a process for controlling the molecular weight of a polymer synthesized by free radical emulsion polymerization that comprises polymerizing at least one monomer by free radical polymerization in an aqueous emulsion in the presence of dibenzyltrithiocarbonate. For instance, dibenzyltrithiocarbonate can be used as a molecular weight regulator in the synthesis of styrene-butadiene rubber by emulsion polymerization. Accordingly, this invention further discloses a process for synthesizing styrene-butadiene rubber (SBR) that comprises copolymerizing styrene monomer and 1,3-butadiene monomer by free radical polymerization in an aqueous emulsion in the presence of dibenzyltrithiocarbonate. The use of dibenzyltrithiocarbonate is inherently less odorous than the use of mercaptans.

Dibenzyltrithiocarbonate molecular weight regulator for emulsion polymerization

High viscosity elastomers are often difficult to utilize in rubber compositions without first creating a pre-blend of the high viscosity elastomer and a rubber processing oil to reduce their overall viscosity. This invention relates to utilization of a specialized pre-blend of high viscosity and low viscosity elastomers for use in rubber compositions and to the resulting rubber composition. The use of such resulting rubber composition may be for component(s) of tires, particularly including tire treads. The specialized pre-blend of high and low viscosity elastomers is required to be created by blending individual latices or, alternatively, by blending individual polymerizates of elastomers with diverse viscosities.

Elastomer blend and use in tires

The present invention relates to a polymer resulting from the copolymerization of at least three monomers. From about 40 to 84 weight percent of the polymer is derived from a conjugated diolefin, from about 15 to 50 weight percent of the polymer is derived from a vinyl substituted aromatic compound and from about 1 to 8 weight percent of the polymer is derived from an olefinically unsaturated nitrile. These polymers may be added to a tread rubber stock for improved wet traction and improved abrasion resistance.

Polymers derived from a conjugated diolefin, a vinyl-substituted

This invention relates to an improved continuous emulsion polymerization process for preparation of flame-retardant latex. Specifically, this invention relates to a novel method for the preparation of high solids, flame-retardant latex with high chlorine content in high conversion containing polymerized vinylidene chloride and at least one monoethylenically unsaturated carboxylic acid. The improved continuous polymerization process is characterized by continuous addition of all of the vinylidene chloride and all of the monoethylenically unsaturated carboxylic acid monomers along with a portion of the remaining monomers to a first reaction vessel followed by the subsequent continuous addition of the rest of the remaining monomers and additional surfactant solution to a second reaction vessel in a chain consisting of three or more reaction vessels. The flame-retardant latices produced by the process of the invention have improved physical and application properties.

Continuous emulsion polymerization process for preparation of

Interpolymers of alpha-olefins and nonconjugated alpha,omega-dienes are prepared by organoaluminum compound-transition metal compound catalysts modified with hexaalkylphosphoric triamides or organophosphate esters.

Preparation of interpolymers of alpha-olefins and nonconjugated alpha,

Acrylonitrile is a monomer that is widely used in the synthesis of a vast variety of polymers. Undesirable quantities of unpolymerized residual acrylonitrile are often present in these acrylonitrile polymers. This residual or free acrylonitrile dissolved in an acrylonitrile polymer and/or its emulsifier system and the water phase used in its polymerization can be reduced significantly in concentration by treatment with saturated 6 to 7 membered ring heterocyclic amines. These amines react with acrylonitrile by a nitrogen-cyanoethylation reaction which results in the formation of a tertiary amino linkage.

Removal of acrylonitrile from latex with saturated heterocyclic amines

Acrylonitrile is a monomer that is widely used in the synthesis of a vast variety of polymers. Undesirable quantities of unpolymerized residual acrylonitrile are often present in these acrylonitrile polymers. This residual or free acrylonitrile dissolved in an acrylonitrile polymer and/or its emulsifier system and the water phase used in its polymerization can be reduced significantly in concentration by treatment with oximes. Oximes react with acrylonitrile by an oxygen-cyanoethylation reaction which results in the formation of a cyanoethyl oximino ether linkage.

Removal of acrylonitrile from latex with oximes

New compositions and a process for the preparation of conjugated diene polymers of broadened molecular weight distribution by reacting non-terminated lithium catalyzed conjugated diene polymers with cyclic organic compounds selected from the group of carbonates, thiocarbonates and sulfites. The resulting new compositions are suitable for use in making high impact plastics and for fabricating rubber goods.

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Tallmadge, OH, United States of America

Michael Leslie Senyek