A composition useful as an asphalt additive includes a plurality of substrate particles and a coating layer disposed on the particles, the coating layer including a solid elastomer. A method of producing an asphalt additive includes mixing an emulsion comprising an elastomer with a plurality of substrate particles. Another composition useful as an asphalt additive includes a plurality of substrate particles substantially coated with a first coating layer and a second coating layer, the first coating layer including a solid elastomer. An asphalt mix includes the asphalt additive composition, aggregate, and a binder.

A composition useful as an asphalt additive includes a plurality of substrate particles and a coating layer disposed on the particles, the coating layer including a solid elastomer. A method of producing an asphalt additive includes mixing an emulsion comprising an elastomer with a plurality of substrate particles. Another composition useful as an asphalt additive includes a plurality of substrate particles substantially coated with a first coating layer and a second coating layer, the first coating layer including a solid elastomer. An asphalt mix includes the asphalt additive composition, aggregate, and a binder.

Crumb rubber obtained from recycled tires is subjected to an interlinked substitution process. The process utilizes a reactive component that interferes with sulfur bonds. The resulting treated rubber exhibits properties similar to those of the virgin composite rubber structure prior to being granulated, and is suitable for use in fabricating new tires, engineered rubber articles, and asphalt rubber for use in waterproofing and paving applications.

Crumb rubber obtained from recycled tires is subjected to an interlinked substitution process. The process utilizes a reactive component that interferes with sulfur bonds. The resulting treated rubber exhibits properties similar to those of the virgin composite rubber structure prior to being granulated, and is suitable for use in fabricating new tires, engineered rubber articles, and asphalt rubber for use in waterproofing and paving applications.

A methacrylic resin composition comprises not less than 90% by mass and not more than 100% by mass of a methacrylic resin [A] having: the total content of a structural unit derived from methyl methacrylate of not less than 90% by mass; a molecular weight M.sub.A of not less than 30000 and not more than 100000 in terms of polystyrene corresponding to the retention time indicating the value of the maximum strength in a chromatogram obtained by gel permeation chromatography; the area S.sub.gA of a region enclosed by an approximate curve obtained by fitting the data of a range indicating the strength of not less than 70% relative to the value of the maximum strength to a Gaussian function by the method of nonlinear least squares and the base line of the chromatogram of 45 to 80% of the area S.sub.A enclosed by the chromatogram and its base line; and the ratio Mw.sub.gA/Mn.sub.gA of a weight average molecular weight Mw.sub.gA to a number average molecular weight Mn.sub.gA of not less than 1.01 and not more than 1.20 in terms of polystyrene computed based on an approximate curve obtained by the above fitting.

A methacrylic resin composition comprises not less than 90% by mass and not more than 100% by mass of a methacrylic resin [A] having: the total content of a structural unit derived from methyl methacrylate of not less than 90% by mass; a molecular weight M.sub.A of not less than 30000 and not more than 100000 in terms of polystyrene corresponding to the retention time indicating the value of the maximum strength in a chromatogram obtained by gel permeation chromatography; the area S.sub.gA of a region enclosed by an approximate curve obtained by fitting the data of a range indicating the strength of not less than 70% relative to the value of the maximum strength to a Gaussian function by the method of nonlinear least squares and the base line of the chromatogram of 45 to 80% of the area S.sub.A enclosed by the chromatogram and its base line; and the ratio Mw.sub.gA/Mn.sub.gA of a weight average molecular weight Mw.sub.gA to a number average molecular weight Mn.sub.gA of not less than 1.01 and not more than 1.20 in terms of polystyrene computed based on an approximate curve obtained by the above fitting.

Elastomer compositions comprising uncured elastomer and reclaimed elastomer are described. In one embodiment, the compositions comprise reclaimed elastomer material (micronized rubber powder) of broad particle size distribution, which is less expensive than traditional reclaimed elastomer material with narrow particle size distribution. Further, compositions comprising reclaimed elastomer materials with broad particle size distribution perform comparably to those comprising reclaimed elastomer materials with narrow particle size distribution. In other embodiments, the compositions comprise both vulcanized and devulcanized elastomer materials. Advantageously, by using a combination of vulcanized and devulcanized material, it is possible to incorporate a greater percentage by weight of reclaimed material in to an elastomer composition, thus providing additional cost savings while maintaining high levels of mechanical properties. Further, the use of the reclaimed material reduces landfill waste resulting in a more environmentally friendly product.

Elastomer compositions comprising uncured elastomer and reclaimed elastomer are described. In one embodiment, the compositions comprise reclaimed elastomer material (micronized rubber powder) of broad particle size distribution, which is less expensive than traditional reclaimed elastomer material with narrow particle size distribution. Further, compositions comprising reclaimed elastomer materials with broad particle size distribution perform comparably to those comprising reclaimed elastomer materials with narrow particle size distribution. In other embodiments, the compositions comprise both vulcanized and devulcanized elastomer materials. Advantageously, by using a combination of vulcanized and devulcanized material, it is possible to incorporate a greater percentage by weight of reclaimed material in to an elastomer composition, thus providing additional cost savings while maintaining high levels of mechanical properties. Further, the use of the reclaimed material reduces landfill waste resulting in a more environmentally friendly product.

A rubber composition is based on at least an elastomer, a reinforcing filler and a crosslinking system and a crumb rubber, said crumb having a particle size distribution such that it comprises less than 35% by weight of particles having a size of less than 50 m and less than 30% by weight of particles having a size of greater than 200 m.

A rubber composition is based on at least an elastomer, a reinforcing filler and a crosslinking system and a crumb rubber, said crumb having a particle size distribution such that it comprises less than 35% by weight of particles having a size of less than 50 m and less than 30% by weight of particles having a size of greater than 200 m.