摘要 |
An objective of the present invention is to provide a block copolymer which is excellent in processability at the time of preparing a rubber composition and leads to a cross-linked rubber composition excellent in tensile property, wearing resistance, weatherability, ozone resistance and heat aging resistance when it is cross-linked, a rubber composition containing the block copolymer and a molded product. The block copolymer of the present invention comprises two polymer blocks each having an ethylenic unsaturated bond and other polymer block which is interposed between two polymer blocks, has a uniform weight average molecular weight in the range from 5,000 to 100,000. The weight average molecular weight of the polymer block having the ethylenic unsaturated bond is preferably in the range from 1,000 to 20,000.
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