Abstract: The subject invention discloses an improved method for making pre-hydrophobated precipitated silica from rice hull ash silica. This process is renewable, highly efficient, and incorporates virtually all of the silica coupling agent used in making the pre-hydrophobated precipitated silica into the final product. The subject invention more specifically reveals a method for making pre-hydrophobated precipitated silica comprising: (1) dispersing silica into water under conditions of agitation to made an aqueous silica slurry; (2) adding a phase transfer agent to the aqueous silica slurry; (3) adding a silica coupling agent to the aqueous silica slurry; (4) maintaining the aqueous slurry at a temperature of at least 20° C. for a time which is sufficient for the silica coupling agent to react with the silica to produce the pre-hydrophobated precipitated silica; and (5) recovering the pre-hydrophobated precipitated silica from the aqueous silica slurry.

Abstract: A rubber composition for incorporation in an engineered article comprises, based on 100 parts by weight (phr) ethylene-propylene-diene copolymer (EPDM) elastomer, from about 5 phr to about 100 phr reinforcing filler preferably comprising a prehydrophobated precipitated silica. In the contemplated embodiment, the EPDM has a diene content that is greater than five percent (5%). The diene also contains branching.

Abstract: This invention is based upon the unexpected finding that the reaction product of polyisobutylene and a silane can be incorporated into tire sealant formulations to greatly reduce the level of hysteresis exhibited by such sealant formulations which decreases the rolling resistance of the tire to improve fuel economy. This is made possible by the further unexpected fining that silanes will react with polyisobutylene by a reaction which is initiated with a peroxide. This invention more specifically discloses a sealant composition which is particularly useful in manufacturing self-sealing tires and which is comprised of (a) the reaction product of polyisobutylene and a silane; and (b) a reinforcing filler. The sealant compositions also contain a peroxide to facilitate partial degradation of the polyisobutylene rubber during the curing of the tire.

Abstract: A rubber composition for incorporation in an engineered article comprises, based on 100 parts by weight (phr) ethylene-propylene-diene copolymer (EPDM) elastomer, from about 5 phr to about 100 phr reinforcing filler preferably comprising a prehydrophobated precipitated silica. In the contemplated embodiment, the EPDM has a diene content that is greater than five percent (5%). The diene also contains branching.

Abstract: This invention is based upon the unexpected discovery that silica containing tire tread rubber performance characteristics, such as hysteresis and payne effect, can be significantly improved using low levels of coupling agents and increasing silanization times and temperatures. The rubbers formulations made in accordance with this finding are of particular value for use in the treads of winter tires. Such rubber formulations will typically be made using a maximum level of about 7 phf of silica coupling agent and will more typically contain 3 phf to 6 phf of the silica coupling. A silanization time of at least 4 minutes or 5 minutes (within the range of 4 to 10 minutes) at a temperature of at least 150° C. and preferably 160° C. (within the range of 150° C. to 180° C.) will also be used.

Abstract: This invention is based upon the unexpected finding that the reaction product of polyisobutylene and a silane can be incorporated into tire sealant formulations to greatly reduce the level of hysteresis exhibited by such sealant formulations which decreases the rolling resistance of the tire to improve fuel economy. This is made possible by the further unexpected fining that silanes will react with polyisobutylene by a reaction which is initiated with a peroxide. This invention more specifically discloses a sealant composition which is particularly useful in manufacturing self-sealing tires and which is comprised of (a) the reaction product of polyisobutylene and a silane; and (b) a reinforcing filler. The sealant compositions also contain a peroxide to facilitate partial degradation of the polyisobutylene rubber during the curing of the tire.

Abstract: This invention is based upon the unexpected discovery that rice husk ash silica (synthetic amorphous silica from rice husk ash) provides an exceptionally good combination of properties when used in certain tire tread rubber formulations, such as an excellent combination of traction, tread-wear, and rolling resistance. These tread rubber formulations are comprised of a blend of high cis-1,4-polybutadiene rubber and a solution styrene-butadiene rubber which is preferably functionalized with amine groups, siloxy groups, thiol groups, carboxyl groups, or groups that are reactive with hydroxyl groups present on the precipitated rice husk ash silica. The use of such rice husk silica as a reinforcing-filler in rubber formulations is also highly desirable because such silica is a sustainable resource (bio-renewable) which is derived from an agricultural waste material which would otherwise be discarded as an undesirable waste product.

Abstract: This invention relates to a rubber composition containing filler reinforcement comprised of precipitated silica with silica coupling agent therefore and conjugated diene-based elastomer which contains end-chain functionalization with multi-functional groups. The groups functionalizing the elastomer are multi-functional in the sense of containing one group reactive with at least one of said precipitated silica and silica coupling agent and another different group reactive with diene-based elastomers through sulfur cure of the rubber composition. A sulfur cured rubber composition containing said end-chain functionalization is provided. A tire is provided having a component comprised of said rubber composition. Representative of said tire component is a tire tread.

Abstract: The method of this invention provides a simple and inexpensive method for manufacturing self-sealing pneumatic rubber tires of the tubeless type having a higher degree of uniformity than can be made utilizing conventional manufacturing procedures that are currently being practiced. In the practice of this invention a low viscosity sealant formulation, which would ordinarily be difficult to handle and build into an uncured tire, is encapsulated in a stiff rubber formulation. This makes it relatively easy to build the sealant layer into the tire since the low viscosity sealant formulation is contained with the more rigid solid material. The low viscosity sealant material requires little and preferably no depolymerization to act effectively as a sealant. Accordingly, it does not need to be depolymerized with a peroxide which causes off-gassing and the resultant tire uniformity and balance issues normally associated with polymer break down.

Abstract: The present invention is directed to improved tire tread compositions, such as silica-filled tire tread compositions, and tires using the same. In one embodiment, a tire tread is provided that includes a diene-based elastomer, a reinforcing filler that includes an inorganic filler (e.g., silica), and a plurality of silane compounds including bis(dialkylalkoxysilyl-alkyl) polysulfide coupling agent and at least one alkoxysilane compound selected from a hydrophobating bis(trialkoxyl)silane coupling and a hydrophobating mono(trialkoxyl)silane dispersing agent.

Abstract: The pneumatic tires of this invention are of the tubeless type, are capable of self-sealing punctures made therein, and generate a low level of noise during use on a vehicle. These tires have a sealant/noise reduction layer which is disposed inwardly from the supporting carcass and which is typically the innermost layer of the tire. The sealant/noise reduction layer is comprised of a dispersed phase and a continuous phase, wherein the dispersed phase is comprised of a sealant material, and wherein the continuous phase is comprised of a foamed polymeric material.

Abstract: This invention reveals an uncured pneumatic tire which is comprised of a generally toroidal-shaped supporting carcass with an outer circumferential tread, two spaced beads, at least one ply extending from bead to bead, sidewalls extending radially from and connecting said tread to said beads, a sealant layer which is disposed inwardly from the supporting carcass, and an innerliner which is disposed inwardly from the sealant layer, wherein said circumferential tread is adapted to be ground-contacting, and wherein the sealant layer is comprised of polyisobutylene or a butyl rubber, wherein the polyisobutylene or the butyl rubber has a number average molecular weight which is within the range of 30,000 to 100,000.

Abstract: The present invention is directed to novel silane disulfide vegetable oils, a method of making the oils, their use in rubber compositions, and their use in tires.

Abstract: The present invention is directed to novel functionalized vegetable oils, a method of making the oils, their use in rubber compositions, and their use in tires.

Abstract: The subject invention is based upon the unexpected discovery that the use of a very specific combination of hydrophobating silanes and sulfur crosslinkable silanes can be used to attain outstanding performance characteristics in silica reinforced rubber formulations. More specifically, these rubber formulations provide a highly desirable combination of both improved abrasion characteristics and reduced hysteresis without compromising other important rubber characteristics. The present invention more specifically discloses a sulfur cured rubber formulation which is the reaction product of (1) at least one rubbery polymer, (2) sulfur, (3) silica, (4) 2 phf to 12 phf of a hydrophobating silane, and (5) 0.5 phf to 3 phf of a crosslinkable silane. The weight ratio of the hydrophobating silane to the crosslinkable silane will typically be within the range of about 2:1 to about 20:1.

Abstract: The subject invention discloses an improved method for making pre-hydrophobated precipitated silica from rice hull ash silica. This process is renewable, highly efficient, and incorporates virtually all of the silica coupling agent used in making the pre-hydrophobated precipitated silica into the final product. The subject invention more specifically reveals a method for making pre-hydrophobated precipitated silica comprising: (1) dispersing silica into water under conditions of agitation to made an aqueous silica slurry; (2) adding a phase transfer agent to the aqueous silica slurry; (3) adding a silica coupling agent to the aqueous silica slurry; (4) maintaining the aqueous slurry at a temperature of at least 20° C. for a time which is sufficient for the silica coupling agent to react with the silica to produce the pre-hydrophobated precipitated silica; and (5) recovering the pre-hydrophobated precipitated silica from the aqueous silica slurry.

Abstract: This invention is based upon the discovery that benzoxazine resins can be incorporated into certain rubber compositions to increase the stiffness thereof without increasing hysteresis or reducing tear strength. Such benzoxazine resin reinforced rubber formulations can accordingly be used beneficially in components of rubber products where high stiffness is desirable. Since these benzoxazine resin reinforced rubbers do not increase levels of hysteresis, they can be used in tires components, such as apexes, chaffers, and high stiffness tread blocks without compromising fuel efficiency. This invention more specifically reveals a radial tire having an apex, a chaffer, or a hard tread block segment which is comprised of a rubbery polymer and a benzoxazine resin.

Abstract: This invention is based upon the unexpected discovery that silica containing tire tread rubber performance characteristics, such as hysteresis and payne effect, can be significantly improved using low levels of coupling agents and increasing silanization times and temperatures. The rubbers formulations made in accordance with this finding are of particular value for use in the treads of winter tires. Such rubber formulations will typically be made using a maximum level of about 7 phf of silica coupling agent and will more typically contain 3 phf to 6 phf of the silica coupling. A silanization time of at least 4 minutes or 5 minutes (within the range of 4 to 10 minutes) at a temperature of at least 150° C. and preferably 160° C. (within the range of 150° C. to 180° C.) will also be used.

Abstract: It has been found that certain silica/cellulose hybrid compositions can be incorporated into rubber formulations with excellent compatibility between the filler and the rubber being attained. These rubber formulations also offer excellent rubber performance characteristics for utilization in tires and other rubber products. These silica/cellulose compositions are made by (1) dispersing sodium silicate or an alkoxy silane into an aqueous cellulose slurry to make an aqueous cellulose dispersion; (2) maintaining the aqueous cellulose dispersion under agitation for a time which is sufficient to allow the sodium silicate or the alkoxy silane to react with the cellulose; (3) adding an acid to the cellulose dispersion in an amount which is sufficient to reduce the pH of the cellulose dispersion to no more than about 8 to produce the silica/cellulose hybrid; and (4) recovering the silica/cellulose hybrid from the water.

Abstract: This invention discloses a technique for replenishing the level of sealant in self-sealing tires at the time that a puncture in the tire is being repaired or when the tire is being recapped. This technique provides the tire with its original level of self-sealing capabilities and will enhance the possibility of the tire remaining in service until it can be conveniently repaired. This method involves (1) injecting a liquid sealant formulation into the sealant layer of a self-sealing tire through at least one puncture hole therein, and (2) sealing the hole or holes in the supporting carcass and the innerliner of the tire. The sealant utilized is typically liquid polyisobutylene having a weight average molecular weight of 25,000 to 200,000. The sealant formulation used can optionally also contain a colorant or a pigment.