A conjugated diene polymer having a high content of cis-1,4-structures with a high activity, a conjugated diene polymer and a modified conjugated diene polymer using the same, a rubber composition for a tire, and a rubber composition for a rubber belt. Described are a catalyst for a conjugated diene polymerization including: a non-metallocene type gadolinium compound (A) represented by the general formula (1); an ionic compound (B) formed of a non-coordinating anion and a cation; and an organic metal compound (C) of an element selected from the group consisting of a group 2, a group 12, and a group 13 of the periodic table, a conjugated diene polymer and a modified conjugated diene polymer obtained using the same, a rubber composition for a tire, and a rubber composition for a rubber belt.

A tire tread comprises a rubber composition based on at least: an elastomer matrix comprising more than 50% by weight of a solution SBR bearing a silanol function and an amine function, a reinforcing filler present at a content of between 40 and 80 phr, which reinforcing filler comprises between 40 and 80 phr of a silica, a coupling agent for coupling the silica to the solution SBR, 10 to 50 phr of a hydrocarbon-based resin having a Tg of greater than 20 C., and 0 to less than 5 phr of a liquid plasticizer. Such a tire has a good performance compromise between rolling resistance and wet grip.

Aliphatic bromine-containing polymers are stabilized using a mixture of an alkyl phosphite and an epoxy compound. This stabilizer package is very effective at preventing cross-linking reactions from occurring when the aliphatic bromine-containing polymer is subjected to high temperatures as are seen in melt processing operations. The stabilized aliphatic bromine-containing polymer is useful as a flame retardant for other polymers, notably polystyrene foam.

A rubber composition is provided that includes a partially halogenated diene polymer that has a controllable microstructure, and no more than about 50% of the n repeat units are in blocks of three or more consecutive units. In embodiments, a reinforcing filler is also included in the rubber composition. In embodiment, the rubber composition is formed into a tire component. A method of making the composition is also provided.

A rubber composition is provided that includes a partially halogenated diene polymer that has a controllable microstructure, and no more than about 50% of the n repeat units are in blocks of three or more consecutive units. In embodiments, a reinforcing filler is also included in the rubber composition. In embodiment, the rubber composition is formed into a tire component. A method of making the composition is also provided.

The invention relates to an energy efficient, fast and environmentally favourable process for the preparation of chlorinated butyl rubbers, that uses hypochloric acid (HOCl) and/or dichlorine monoxide (Cl.sub.2O) as halogenating agent. The chlorinated butyl rubbers prepared according to the aforementioned process exhibit an advantageous microstructure and a desirable content and ratio of chlorinated and non-chlorinated oligomers and are therefore also encompassed by the invention. The teachings herein also relate to chlorinated copolymers and polymer products that include a chlorinated copolymer.

The invention relates to an energy efficient, fast and environmentally favourable process for the preparation of chlorinated butyl rubbers, that uses hypochloric acid (HOCl) and/or dichlorine monoxide (Cl.sub.2O) as halogenating agent. The chlorinated butyl rubbers prepared according to the aforementioned process exhibit an advantageous microstructure and a desirable content and ratio of chlorinated and non-chlorinated oligomers and are therefore also encompassed by the invention. The teachings herein also relate to chlorinated copolymers and polymer products that include a chlorinated copolymer.

Provided are a rubber composition which provides a self-healing rubber with improved strength and wet grip performance, and a pneumatic tire including the rubber composition. The present disclosure relates to a rubber composition containing a rubber component having a functional group containing a cationic functional group and/or an anionic functional group, a filler capable of generating a charge paired with the functional group, and sulfur.

Provided are a rubber composition which provides a self-healing rubber with improved strength and wet grip performance, and a pneumatic tire including the rubber composition. The present disclosure relates to a rubber composition containing a rubber component having a functional group containing a cationic functional group and/or an anionic functional group, a filler capable of generating a charge paired with the functional group, and sulfur.

Methods for controlling molecular weight distribution of elastomer compositions and, in particular isobutylene-based elastomer compositions, particularly for use in tire compositions such as innerliners. A polymerization medium comprising monomers, diluent, and a catalyst system are polymerized in a reactor. Molecular weight distribution is controlled using post-polymerization processing to achieve a Mooney Relaxation Index of greater than about 2.5.