| 摘要 |
PURPOSE:To obtain a diaphragm or a center cap excellent in physical properties and economy by injection-molding or compression-molding polymethylpentene. CONSTITUTION:A diaphragm or a center cap is obtained by injection-molding or compression-molding polymethylpentene obtained by dimerizing propylene and polymerizing the dimer optically together with a filler such as carbon, whisker or mica. According to the above production process, the molding can be easily performed because the polymer can be molded at about 200 deg.C, while a liquid crystal polymer needs to be heated to 250 deg.C or higher. Further, the specific gravity is lower than that of a liquid crystal polymer. The heat resistance temperature is higher than that of polypropylene. |
