Abstract: Old, spent or worn tires are recycled by removing non-rubber components such as belts, beads, and fabric, and grinding the remaining cured rubber into fine sized particles. The ground particles generally replace equivalent amounts of rubber and additives in various tire formulated components such as tire treads. Good physical properties of the end product are retained.
Type:
Grant
Filed:
August 27, 1999
Date of Patent:
July 24, 2001
Assignee:
Bridgestone/Firestone Research, Inc.
Inventors:
Jamie J. McNutt, Michael S. James, William J. O'Briskie, William J. Corsaut
Abstract: The invention provides solid supported anionic catalysts, suitable for gas phase anionic polymerization of conjugated diene monomers, that are useful for anionically producing very high molecular weight branched diene polymers, such as styrene butadiene rubber, polybutadiene rubber, polyisoprene rubber, and the like. The catalysts comprise a metalatable particle, such as a bound rubber, a thermoplastic polymer or a cured elastomer, that is multiply metalated with Group IA alkali metal atoms. The multi-branched diene polymers obtained by gas phase anionic polymerization employing the catalysts exhibit desirable properties, such as an extremely high molecular weight, a controlled molecular weight distribution, Tg and vinyl content, and the ability to readily absorb hydrocarbon solvents and oils. The polymers are easily compounded to form vulcanizable elastomeric compounds and articles, such as tires, that have excellent resistance to wear and tear and exhibit reduced hysteresis properties.
Type:
Grant
Filed:
November 23, 1999
Date of Patent:
July 10, 2001
Assignee:
Bridgestone Corporation
Inventors:
William M. Cole, William L. Hergenrother, Theodore J. Knutson, Georg G. A. Böhm
Abstract: A method for controlling any increase in Mooney viscosity during aging of siloxane-functionalized polymers includes the step of adding a viscosity stabilizing effective amount of a viscosity stabilizing agent selected from the group consisting of alkyl alkoxysilanes of the structural formula
R1nSi(OR2)4-n
wherein R1 is selected from the group consisting of C1 to C20 alkyl, C4 to C10 cycloalkyl, or C5 to C20 aromatic groups, wherein R2 may be the same as or different from R1 and is selected from the group consisting of C1 to C20 alkyl, C4 to C10 cycloalkyl, or C5 to C20 aromatic groups, and wherein n is an integer from 1 to 3. The method provides for the stabilization of Mooney viscosity of siloxane-functionalized polymers at any given level upon aging. The viscosity stabilizing agents react with the siloxane-functionalized polymers during hydrolysis of the siloxane end groups to form moisture stabilized polymers.
Type:
Grant
Filed:
July 26, 1999
Date of Patent:
July 3, 2001
Assignee:
Bridgestone Corporation
Inventors:
Terrence E. Hogan, Chen-Chy Lin, William L. Hergenrother
Abstract: The invention provides solid supported anionic catalysts, suitable for gas phase anionic polymerization of conjugated diene monomers, that are useful for anionically producing very high molecular weight branched diene polymers, such as styrene butadiene rubber, polybutadiene rubber, polyisoprene rubber, and the like. The catalysts comprise a metalatable particle, such as a bound rubber, a thermoplastic polymer or a cured elastomer, that is multiply metalated with Group IA alkali metal atoms. The multi-branched diene polymers obtained by gas phase anionic polymerization employing the catalysts exhibit desirable properties, such as an extremely high molecular weight, a controlled molecular weight distribution, Tg and vinyl content, and the ability to readily absorb hydrocarbon solvents and oils. The polymers are easily compounded to form vulcanizable elastomeric compounds and articles, such as tires, that have excellent resistance to wear and tear and exhibit reduced hysteresis properties.
Type:
Grant
Filed:
November 23, 1999
Date of Patent:
July 3, 2001
Assignee:
Bridgestone Corporation
Inventors:
William M. Cole, William L. Hergenrother, Theodore J. Knutson, Georg G. A. Böhm
Abstract: A spacer for an air spring assembly includes a substantially cylindrical body having a substantially planar mounting surface. The body includes a central hub, an outer rim, and a plurality of structural arms connecting the outer rim to the central hub. The central hub includes a pair of concentric hub walls with a plurality of spoke ribs disposed between the hub walls. The outer rim includes an annular groove in its upper surface as well as a plurality of support ribs. Each of the structural arms has a T-shaped cross section. The spacer has five bolt holes that are configured to work with a single center mount, two point, three point, or a four point mounting pattern. The spacer is fabricated from a non-metallic material such as a high strength, lightweight plastic or fiber reinforced plastic.
Type:
Grant
Filed:
March 30, 1999
Date of Patent:
June 26, 2001
Assignee:
Bridgestone/Firestone, Inc.
Inventors:
Paul P. Koeske, Mohamad Taghizadeh, Pradipta N. Moulik, Todd M. Ziems, Andreas Peickert
Abstract: The reduction of hysteresis in a silica-filled, vulcanized elastomeric compound is produced by mixing diene monomer and optionally monovinyl aromatic monomer with an initiator and a coordinator; effecting polymerization conditions; terminating polymerization with a terminator containing an organo-tin group to form a tin-coupled diene elastomer; compounding the tin-coupled diene elastomer with an amorphous silica filler and a vulcanization agent; and, effecting vulcanization. A pneumatic tire tread stock incorporating the vulcanized elastomer compound exhibits decreased rolling resistance in the tire.