Terminated Polylactic Acid Synthesized by Solution Polycondensation Combined with Melt Polycondensation

Terminated polylactic acid were synthesized from D,L-lactic acid and 1,4-buta-nediol by solution polymerization combined with melt polycondensation. The chemical structure and property of terminated polylactic acid were characterized by FTIR,1H NMR,universal testing machine and TGA. The results showed that the catalytical effects of 0. 5 %SnCl2and 0. 3 % P-TSA were best. The Mηof terminated polylactic acid was 32653 within 10 h,which was two times higher than the Mηof product by direct melt polyconde-nsation under the same synthetic condition,and the product had the best mechanical prop-erties and thermal stability.