STRONGLY STRETCHED ALIPHATIC POLYESTER MOLDINGS

摘要

Stretched aliphatic polyester moldings remarkably improved in various properties such as impact resistance and gas barrier properties including resistance to boiling water are provided by subjecting crystalline aliphatic polyester moldings or laminates to strong stretching under properly set stretching conditions. The stretched aliphatic polyester moldings include (i) such a molding having a crystal-melting point much higher than that of unstretched one, (ii) such a molding exhibiting an enhanced peak temperature of beta-dispersion in dynamic viscoelasticity measurement, and (iii) such a molding enhanced in the degree of orientation as determined by wide-angle X-ray diffractometry and exhibiting an enhanced peak temperature of alpha-dispersion in dynamic viscoelasticity measurement. In the molding (iii), enhancement in degree of orientation is observed not only in the amorphous moieties but also in the crystalline moieties.