Without significantly impacting monomer conversion, the cis-1,4 mer content of conjugated diene mer in polymers can be increased by adding one or more Lewis bases to a catalyst composition that includes a Group 3 metal atom-containing carboxylate. This effect can be seen even at above average monomer concentrations.

Without significantly impacting monomer conversion, the cis-1,4 mer content of conjugated diene mer in polymers can be increased by adding one or more Lewis bases to a catalyst composition that includes a Group 3 metal atom-containing carboxylate. This effect can be seen even at above average monomer concentrations.

A process for preparing a functionalized polybutadiene is provided. The process comprises the following steps: a) homopolymerising butadiene with a catalytic system based on at least one preforming conjugated diene, a salt of one or more rare earth metals of an organic phosphoric acid, an aluminium-containing alkylating agent, an alkylaluminium halide; b) adding a polyfunctional compound to the pseudo-living elastomer formed in step (a); and c) adding a functionalizing agent to the mixture formed in step (b). The total molar amount of aluminium in the polymerization medium is such that the (aluminium/rare earth salt) molar ratio has a value between 1 and 5 and the polymerization is carried out at a temperature between 40° C. and 90° C. A functionalized polybutadiene that can be obtained by the process, and a rubber composition containing the functionalized polybutadiene is also provided.

A process for preparing a functionalized polybutadiene is provided. The process comprises the following steps: a) homopolymerising butadiene with a catalytic system based on at least one preforming conjugated diene, a salt of one or more rare earth metals of an organic phosphoric acid, an aluminium-containing alkylating agent, an alkylaluminium halide; b) adding a polyfunctional compound to the pseudo-living elastomer formed in step (a); and c) adding a functionalizing agent to the mixture formed in step (b). The total molar amount of aluminium in the polymerization medium is such that the (aluminium/rare earth salt) molar ratio has a value between 1 and 5 and the polymerization is carried out at a temperature between 40° C. and 90° C. A functionalized polybutadiene that can be obtained by the process, and a rubber composition containing the functionalized polybutadiene is also provided.

An object of the present invention is to provide a novel method of producing a nonpolar olefin polymer (e.g., a copolymer of a nonpolar olefin and a polar olefin). The present invention provides a method of producing a polar olefin polymer or copolymer, the method including the polymerization step of polymerizing a polar olefin monomer using, as a catalyst, a polymerization catalyst composition containing: 1) a metallocene complex represented by Formula (I), which contains a central metal M that is scandium (Sc) or yttrium (Y), a ligand Cp* containing a cyclopentadienyl derivative and being bound to the central metal, monoanionic ligands Q.sup.1 and Q.sup.2, and W neutral Lewis bases L wherein W is an integer of 0 to 3; and 2) an ionic compound composed of a non-coordinating anion and a cation. ##STR00001## ##STR00002##

An object of the present invention is to provide a novel method of producing a nonpolar olefin polymer (e.g., a copolymer of a nonpolar olefin and a polar olefin). The present invention provides a method of producing a polar olefin polymer or copolymer, the method including the polymerization step of polymerizing a polar olefin monomer using, as a catalyst, a polymerization catalyst composition containing: 1) a metallocene complex represented by Formula (I), which contains a central metal M that is scandium (Sc) or yttrium (Y), a ligand Cp* containing a cyclopentadienyl derivative and being bound to the central metal, monoanionic ligands Q.sup.1 and Q.sup.2, and W neutral Lewis bases L wherein W is an integer of 0 to 3; and 2) an ionic compound composed of a non-coordinating anion and a cation. ##STR00001## ##STR00002##

The present invention relates to a conjugated diene-based polymer having high processability and excellent compounding properties, a preparation method thereof and a rubber composition including same, and provides a neodymium-catalyzed conjugated diene-based polymer satisfying all conditions of (a) to (c), a preparation method thereof and a rubber composition including same.

The present invention relates to a conjugated diene-based polymer having high processability and excellent compounding properties, a preparation method thereof and a rubber composition including same, and provides a neodymium-catalyzed conjugated diene-based polymer satisfying all conditions of (a) to (c), a preparation method thereof and a rubber composition including same.

A golf ball material contains (I) a multi-component copolymer having conjugated diene units, non-conjugated olefin units and aromatic vinyl units; and (II) a binary copolymer of an olefin and an α,β-unsaturated carboxylic acid of 3 to 8 carbons and/or a ternary copolymer of an olefin, an α,β-unsaturated carboxylic acid of 3 to 8 carbons and an ester of the α,β-unsaturated carboxylic acid, or a metal neutralization product thereof.

The conjugated diene units include butadiene units, the non-conjugated olefin units include units selected from the group consisting of ethylene, propylene and 1-butene units, and the aromatic vinyl units include styrene units. The content of the conjugated diene units in the multi-component copolymer (I) is 5 wt % or more. This golf ball material is soft and has an excellent rebound resilience. Golf balls which use this material in the cover provide golfers with a competitive edge.

A golf ball material contains (I) a multi-component copolymer having conjugated diene units, non-conjugated olefin units and aromatic vinyl units; and (II) a binary copolymer of an olefin and an α,β-unsaturated carboxylic acid of 3 to 8 carbons and/or a ternary copolymer of an olefin, an α,β-unsaturated carboxylic acid of 3 to 8 carbons and an ester of the α,β-unsaturated carboxylic acid, or a metal neutralization product thereof.

The conjugated diene units include butadiene units, the non-conjugated olefin units include units selected from the group consisting of ethylene, propylene and 1-butene units, and the aromatic vinyl units include styrene units. The content of the conjugated diene units in the multi-component copolymer (I) is 5 wt % or more. This golf ball material is soft and has an excellent rebound resilience. Golf balls which use this material in the cover provide golfers with a competitive edge.