Patent ID: 8557915
Filing Date: 2013-10-15
Classification: C08F,C08K,C08L

Abstract:
1. A process for producing a conjugated diene polymer comprising a polymerization step wherein a conjugated diene polymer having a cis-1,4-bond content of 98.5 mass % or more and a ratio (Mw/Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) measured by gel permeation chromatography of 2.5 or less is obtained by carrying out a polymerization reaction in conjugated diene compounds using a catalyst composition containing the following components (a) to (c): component (a) a rare earth element-containing compound which comprises at least a rare earth element of an atomic number of 57 to 71 in the periodic table, or a reaction product of the rare earth element-containing compound with a Lewis base, component (b) an aluminoxane and an organoaluminum compound shown by a general formula AlR component (c) an iodine-containing compound which comprises at least one iodine atom in the molecular structure.