| 摘要 |
PURPOSE:To prepare a crystalline polymer having a high melt-viscosity by thermally treating a crystalline polymer forming an anisotropic melted product at a specific temperature. CONSTITUTION:A crystalline polymer preferably comprising 65-85mol.% of repeating units of formula I and 15-35mol.% of repeating units of formula II is preliminarily treated at a temperature between the vicat softening point and the melting point of the polymer (preferably 120-350 deg.C) preferably for 3-30hr in an inert gas, atmosphere etc. The pre-treated polymer alone or a composition containing the polymer in an amount of preferably 80wt.% is molded preferably by an inflation method to prepare a crystalline polymer film having high elastic modulus and strength. |
