abstract |
A propylene homopolymer or a copolymer of propylene and an alpha-olefin with at least 4 carbon atoms, which is produced through polymerization in the presence of a metallocene catalyst and which has an increased isotactic pentad fraction and a reduced molecular weight distribution; and also a propylene-based polymer composition as prepared by adding a nucleating agent to the homopolymer or the copolymer are superior to conventional polymers and polymer compositions, as they have well-balanced toughness and heat-sealability, and are not sticky, and, in addition, they have excellent anti-blocking properties. Their films especially those for wrapping and packaging edibles are tough and have excellent anti-blocking properties, and high film impact resistance. The polymer and the polymer composition have good moldability. |