| 摘要 |
PROBLEM TO BE SOLVED: To provide an olefin block copolymer which exhibits excellent elasticity, heat resistance, and processability.SOLUTION: The olefin block copolymer comprises: a plurality of blocks or segments, each comprising ethylene or propylene repeating units and α-olefin repeating units at mole fractions different from each other; and a polymer chain having 20-100 branched chains per 1,000 carbons. In a distribution curve which shows a relationship between a branched chain number Y per 1,000 carbons of each polymer chain and a molecular weight X of each polymer chain, a region where Y increases with an increase in X and a region where Y decreases with the increase in X exist, and an inflection point existing between the regions exists between the minimum and maximum values of X and in a region less than maximum peak molecular weight of the block copolymer. |
