METHOD FOR PRODUCING POLY-L-LACTIC ACID BY DIRECTLY POLYCONDENSATING L-LACTIC ACID

摘要

The invention relates to a method for producing high-molecular poly-L lactic acid by directly polycondensating L-lactic acid using a melt-phase condensation and a subsequent solid-phase condensation by means of acidic and supported solid catalysts. The invention also relates to the use of an acidic and supported solid catalyst for producing high-molecular poly-L lactic acid by directly polycondensating L- lactic acid, preferably supported and calcined zirconium sulfate.