A method for preparing cis-1,4-polydienes having useful resistance to cold flow, the method comprising the steps of preparing a polymerization system including a reactive polymer by introducing a lanthanide-based catalyst and a conjugated diene monomer and adding a Lewis acid to the polymerization system including a reactive polymer.

A method for preparing cis-1,4-polydienes having useful resistance to cold flow, the method comprising the steps of preparing a polymerization system including a reactive polymer by introducing a lanthanide-based catalyst and a conjugated diene monomer and adding a Lewis acid to the polymerization system including a reactive polymer.

A method for preparing cis-1,4-polydienes, the method comprising the steps of preparing a preformed, active lanthanide-based catalyst, aging the active lanthanide-based catalyst for more than 5 days to thereby formed an aged catalyst, and introducing the aged catalyst and conjugated diene monomer to be polymerized to thereby form an active polymerization mixture in which the conjugated diene monomer is polymerized to form a polydiene having a reactive chain end.

A method for preparing cis-1,4-polydienes, the method comprising the steps of preparing a preformed, active lanthanide-based catalyst, aging the active lanthanide-based catalyst for more than 5 days to thereby formed an aged catalyst, and introducing the aged catalyst and conjugated diene monomer to be polymerized to thereby form an active polymerization mixture in which the conjugated diene monomer is polymerized to form a polydiene having a reactive chain end.

Provided is a thermoplastic elastomer composition for a weather strip material which is used for obtaining a molded product which has excellent adhesiveness to both a thermoplastic elastomer adherend and a crystalline ethylene resin adherend and also has excellent heat resistance at a fused portion. The thermoplastic elastomer composition for a weather strip material according to the disclosure contains: an ethylene-α-olefin copolymer rubber (A); an α-olefin crystalline thermoplastic resin (B) having a melting point of 140° C. or higher; an olefin block copolymer (C) obtained by hydrogenating a block copolymer which has a conjugated diene polymer block with a 1,2-vinyl bond content of 25 mol % or less at both ends and also has a conjugated diene polymer block with a 1,2-vinyl bond content of more than 25 mol % in the middle; and a crystalline ethylene resin (D).

Provided is a thermoplastic elastomer composition for a weather strip material which is used for obtaining a molded product which has excellent adhesiveness to both a thermoplastic elastomer adherend and a crystalline ethylene resin adherend and also has excellent heat resistance at a fused portion. The thermoplastic elastomer composition for a weather strip material according to the disclosure contains: an ethylene-α-olefin copolymer rubber (A); an α-olefin crystalline thermoplastic resin (B) having a melting point of 140° C. or higher; an olefin block copolymer (C) obtained by hydrogenating a block copolymer which has a conjugated diene polymer block with a 1,2-vinyl bond content of 25 mol % or less at both ends and also has a conjugated diene polymer block with a 1,2-vinyl bond content of more than 25 mol % in the middle; and a crystalline ethylene resin (D).

The invention discloses an iron bipyridine complex, a preparation method of the same, and use of the same in polymerization of conjugated dienes the invention provides an iron bipyridine complex, which is used as a primary catalyst showing high activity in the polymerization of polyprene to obtain a polymer with a high branched-chain degree. The polymer has the characteristics of a high molecular weight and narrow molecular weight distribution, and the molecular weight of the polymer can be adjusted by a chain transfer reagent. The obtained poly(conjugated diene) rubber has high branched-chain content and an ultrahigh molecular weight. Because there are a large number of side groups on the molecular chains of the rubber, the rubber is mainly used for preparing high-performance tires and other related rubber products with good wet traction and low friction-induced heat generation.

An ultra-light graphene-rubber foam particle for soles is prepared from, by weight, 60-65 parts of natural rubber, 8-12 parts of isoprene rubber, 8-12 parts of butadiene rubber, 6-8 parts of styrene butadiene rubber, 0.8-1.0 parts of modified graphene, 0.08-0.12 parts of poly(N-vinylacetamide), 0.8-1.0 parts of silicone oil, 3.0-3.5 parts of inorganic nano-particles, 1.2-1.5 parts of activated zinc oxide, 0.8-1.0 parts of zinc stearate, 1.0-1.2 parts of stearic acid, 0.8-1.0 parts of cross-linking agents, 2.0-3.0 parts of flow promotors, and 1.5-1.8 parts of foaming agents. According to the invention, the modified graphene is uniformly dispersed into the rubber materials, so that the ultra-light graphene-rubber foam particle has good thermal stability, wear resistance and tensile strength, the permanent compressive-deformation performance and thermal contraction resistance are improved, and the weight is reduced by over 50%.

An ultra-light graphene-rubber foam particle for soles is prepared from, by weight, 60-65 parts of natural rubber, 8-12 parts of isoprene rubber, 8-12 parts of butadiene rubber, 6-8 parts of styrene butadiene rubber, 0.8-1.0 parts of modified graphene, 0.08-0.12 parts of poly(N-vinylacetamide), 0.8-1.0 parts of silicone oil, 3.0-3.5 parts of inorganic nano-particles, 1.2-1.5 parts of activated zinc oxide, 0.8-1.0 parts of zinc stearate, 1.0-1.2 parts of stearic acid, 0.8-1.0 parts of cross-linking agents, 2.0-3.0 parts of flow promotors, and 1.5-1.8 parts of foaming agents. According to the invention, the modified graphene is uniformly dispersed into the rubber materials, so that the ultra-light graphene-rubber foam particle has good thermal stability, wear resistance and tensile strength, the permanent compressive-deformation performance and thermal contraction resistance are improved, and the weight is reduced by over 50%.

A modified conjugated diene-based polymer represented by Formula 1, wherein a terminal of a polymer chain is modified, and a method for preparing same are provided. By including a modifier derived unit having a specific structure, a beta value affecting cold flow may be reduced through controlling the degree of branch, and accordingly, the cold flow of a polymer may be efficiently controlled and a mooney viscosity increasing ratio may be improved.