Thermal properties of copoly(L-lactic acid/glycolic acid) by direct melt polycondensation

摘要

Poly( L-lactic acid-co-glycolic acid) ( PLGA) was prepared from hydroxy-acids with melt polymerization. In this way, the copoly( L-LA/GA) ( PLGA) was synthesized directly using a binary catalyst ( tin chloride dihydrate/p-toluenesulfonic acid). The thermal properties of PLGA were studied by differential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR). The results show that the melting point of PLGA decreases with increasing mole fraction of GA units in the copolymer. In addition, the melting point of polymer also decreases with increasing degree of racemization of the polymer.