Bridgestone Corporation

Jsr Corporation

Eiju Suzuki

Steven Luo

Yoichi Ozawa

Terrence Eugene Hogan

Yuan-Yong Yan

Jason T Poulton

Dennis R Brumbaugh

Zengquan Qin

Christine M Rademacher

Ryuji Nakagawa

Ken Tanaka

Shojiro Kaita

Takuo Sone

Junko Matsushita

Yasuo Wakatsuki

Takaomi Matsumoto

Yuki Itoh

Junko Kurazumi

Tetsuya Omura

Kouji Masaki

Tetsuya Ohmura

Yudai Yabe

Ryouta Tamate

The side-reinforcing rubber for run-flat tires of the present invention is a side-reinforcing rubber for run-flat tires, including a vulcanized rubber which is formed of a rubber composition containing a rubber component containing a dienic rubber, a vulcanizing agent, and a carbon black having a dibutyl phthalate oil absorption of 120 mL/100 g or more, and has a specific surface area according to a nitrogen adsorption method of 20 to 80 m/g, with a ratio of an Sx bond (where x is 3 or more) to all sulfide bonds in the side-reinforcing rubber for run-flat tires being 40% or less. The side-reinforcing rubber for run-flat tires is excellent in durability life.

Side-reinforcing rubber for run-flat tire and run-flat tire

A method for preparing a functionalized polymer, the method comprising the steps of: (i) polymerizing monomer with an anionic initiator to form a reactive polymer; and (ii) reacting the reactive polymer with a nitrile compound containing a protected amino group, where the protected amino group is directly attached to a moiety selected from the group consisting of acyclic moieties, heterocyclic moieties, and non-aromatic cyclic moieties.

Polymers functionalized with nitrile compounds containing a protected amino group

The invention relates to a rubber composition having better workability and fracture resistance than the prior art, and more specifically, to a rubber composition containing a polymer (B) obtained from an emulsion-polymerized polymer latex (A) having a number average molecular weight in the range of 1,000-130,000.

Rubber composition and tire using the same

A process for preparing a copolymer of an acyclic conjugated diene and a cyclic conjugated diene using a polymerization catalyst system comprising a transition metal compound or a lanthanide metal compound, an alkylating agent, and an inorganic halide alcoholate, and rubber compositions and tires comprising the same. The copolymer contains at least 90% acyclic conjugated diene monomer, has a number average molecular weight of between 40,000 and 300,000, and has a cis-bond content of at least 92%.

Processes for preparation of cyclic and acyclic diene copolymer and rubber composition

This invention relates to a rubber composition including a polyisoprene rubber having a very high cis-1,4-bond content and having an excellent balance between dynamic properties and processability, and more particularly to a rubber composition comprising as a rubber component (A) a synthetic polyisoprene rubber having a cis-1,4-bond content of not less than 99.0%, a 3,4-bond content of not more than 0.5% and a Mooney viscosity ML(100&#xb0; C.) of 20-110 and (B) a natural rubber.

A method for preparing a functionalized polymer, the method comprising the steps of preparing a reactive polymer, and reacting the reactive polymer with a halosilane compound containing an amino group.

Polymers functionalized with halosilanes containing an amino group

A method for preparing a polydiene polymer, the method comprising: (i) preparing an active polymerization mixture by introducing conjugated diene monomer, and optionally monomer copolymerizable therewith, and a lanthanide-based catalyst system; (ii) adding a nitrile compound containing a protected amino group to the active polymerization mixture; and (iii) adding a co-functionalizing agent to the active polymerization mixture.

Compositions and methods for producing polymerization initiators comprising at least two protected primary amine groups. Polymers prepared using such polymerization initiators can comprise a residue of the polymerization initiator and can initially comprise the at least two protected primary amine groups. Such polymers can undergo a deprotection process thereby yielding a polymer having one or more unprotected primary amine groups. Polymers having primary amine groups can be employed in rubber compositions, which have a variety of potential applications, such as, for example, in tire manufacturing.

Compositions and method for producing poly-aminofunctionalized polymerization initiators and corresponding polymers

A method for preparing a functionalized polymer, the method comprising the steps of (i) polymerizing conjugated diene monomer by employing a lanthanide-based catalyst to form a reactive polymer, and (ii) reacting the reactive polymer with a protected oxime compound.

Polymers functionalized with protected oxime compounds

A method for preparing a functionalized polymer, the method comprising the steps of (i) polymerizing monomer with a coordination catalyst to form a reactive polymer; and (ii) reacting the reactive polymer with a nitrile compound containing a protected amino group.

The present invention provides a modified polymer, which is obtained by reacting, with an active metal bonded to a polymer, a modifier represented by the general formula (I) (where Xto Xeach represent a hydrogen atom or a specific monovalent functional group, and at least one of those is other than a hydrogen atom, Rto Reach represent a single bond or a divalent hydrocarbon group having 1 to 18 carbon atoms, and a plurality of aziridine rings may be bonded through any of Xto Xand Rto R). More particularly, the present invention provides a novel modified polymer which has excellent interaction with carbon black and enables improvement in dispersibility of the carbon black when used in a rubber composition blended with the carbon black, a rubber composition containing the modified polymer and capable of providing a tire excellent in low heat generating property, rupture characteristics, and abrasion resistance, and a tire made of the rubber composition and having the above-mentioned characteristics.

Modified polymer, rubber composition, and tire

The present invention provides a modified conjugated diene polymer that is prepared by polymerization of a conjugated diene compound using a catalyst containing a lanthanoid rare earth element compound in an organic solvent and then modifying the resulting polymer having an active organic metal site with a modifier, wherein the modification efficiency is not less than 15% and the cis-1,4 bond content in the conjugated diene moiety measured by Fourier transform infrared spectroscopy satisfies the relationship (I):cis-1,4 bond content&#x2267;98.00(%)&#x2003;&#x2003;(I),or the modification efficiency is not less than 75% and the cis-1,4 bond content in the conjugated diene moiety measured by Fourier transform infrared spectroscopy satisfies the relationship (II):94.00(%)&#x2266;cis-1,4 bond content&#x3c;98.00(%)&#x2003;&#x2003;(II).The invention further provides a rubber composition containing the modified conjugated diene polymer and giving a tire exhibiting low heat build-up, satisfactory failure characteristics, and high abrasion resistance, and a tire composed of the rubber composition and exhibiting these characteristics.

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Tokyo, Japan

Eiju Suzuki