| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for efficiently producing a propylene-based polymer suitable to blow molding, extrusion foaming molding, etc., by a simple technique, which has good flow characteristics such as melt tension and melt viscoelasticity, is accordingly excellent in mold processability at blow molding by virtue of high swell ratio, and can enhance a closed cell rate by virtue of exhibiting high strain-hardening at extrusion foaming molding. SOLUTION: The method for producing the propylene-based polymer includes polymerization of propylene in the presence of the catalyst containing at least the following components [A] to [C]. [A] At least two transition metal compounds respectively selected from the following components [A-1] and [A-2], which are compounds of transition metals of group 4 of the periodic table, wherein the ratio of the molar amount of the component [A-1] to the total molar amount of the components [A-1] and [A-2] is 0.20-0.99: [A-1] a compound (having a bisindenyl structure) represented by formula (a1), [A-2] a compound (having a biscyclopentadienyl structure) represented by formula (a2). [B] At least one selected from the group consisting of [B-1] an aluminum oxy compound, [B-2] an ionic compound or a Lewis acid convertible to a cation by a reaction with the transition metal compound [A], [B-3] solid acid fine particles, and [B-4] an ion-exchangeable layered silicate salt. [C] An organoaluminum compound. COPYRIGHT: (C)2011,JPO&INPIT |
