Patent ID: 7771493
Filing Date: 2010-08-10
Classification: B29B,B29K,C08G

Abstract:
1. A process for crystallising polyhydroxycarboxylic acid having a glass transition temperature Tg of 50 to 70° C., wherein the polyhydroxycarboxylic acid is formed into amorphous granules, which comprises preheating said amorphous polyhydroxycarboxylic acid granules to a temperature of at least 40 to 5° C. below their Tg, subjecting the amorphous granules to a temperature of >70 to 100° C. in water for a duration of 3 to 5 minutes, subsequently separating the water and drying the at least semi-crystalline granulate, wherein the polyhydroxycarboxylic acid granules have a crystallinity of 80-100% after drying.