Bulk polycondensation of glycolic acid (GA) was studied to obtain high- molecular-weight poly(glycolic acid) (PGA). At first, a solid oligocondensate was prepared by melt-polycondensation of GA at 190°C, and then it was subjected to solid-state polycondensation at the same temperature to increase the molecular weight. After the catalyst screening, zinc acetate dihydrate was discovered to be the best catalyst. The weight-average molecular weight of PGA reached 91,000, which was at the same level with that of PGA prepared by the conventional ring-opening polymerization of glycolide. This process can afford a facile route to large-scale synthesis of PGA. (C) 2000 Elsevier Science Ltd.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Materials Chemistry