摘要 |
A production process of a propylene block copolymer, comprising the step (I) of polymerizing propylene alone or a combination of propylene with an olefin other than propylene, in the presence of a defined polymerization catalyst, to form a polymer component (1), and the step (II) of copolymerizing propylene with an olefin other than propylene in the presence of the polymer component (1), to form a polymer component (2), wherein a combination of a transition metal compound such as Zr(OR1)4 and Hf(OR1)4 (R1 being a hydrocarbon group) with an ether group-containing linear hydrocarbon compound and/or a Lewis base compound is added to the above polymerization system between the ending point of the step (I) and the starting point of the step (II), or during the step (II).
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