CRYSTALLINE POLYGLYCOLIC ACID,POLYGLYCOLIC ACID COMPOSITION AND PROCESSES FOR PRODUCTION OF BOTH

摘要

Crystalline polyglycolic acid wherein a difference between the melting point Tm and the crystallization temperature Tc2 is not lower than 35 DEG C, and a difference between the crystallization temperature Tc1 and the glass transition temperature Tg is not lower than 40 DEG C. A production process of polyglycolic acid modified in crystallinity, comprising applying heat history to crystalline polyglycolic acid at a temperature of not lower than (the melting point Tm of the crystalline polyglycolic acid + 38 DEG C). A polyglycolic acid composition comprising crystalline polyglycolic acid and a heat stabilizer, wherein a difference (T2 - T1) between the temperature T2 at 3%-weight loss on heating of the polyglycolic acid composition and the temperature T1 at 3%-weight loss on heating of the crystalline polyglycolic acid is not lower than 5 DEG C.