| 摘要 |
PURPOSE:To obtain a syndiotactic polypropylene foam which is inexpensive and is excellent in heat resistance, etc., by mixing a blowing agent with a syndiotactic polypropylene and foaming the mixture by heating. CONSTITUTION:A syndiotactic polypropylene is produced by, e.g. polymerizing propylene or copolymerizing propylene with another alpha-olefin (e.g. ethylene) by using a transition metal compound having asymmetrical ligands such as isopropyl(cyclopentadienyl-1-fluorenyl)zirconium chloride and an aluminoxane (e.g. methylamuminoxane) as a catalyst. This polypropylene is mixed with a blowing agent (e.g. difluorodichloromethane), heated and foamed at an expansion ratio of at least two to obtain a syndiotactic polypropylene foam. |
