Direct synthesis of poly (glycolic acid-lactic acid) from D,L-lactic acid via melt polycondensation and its characterization

Starting from glycolic acid (GA) and D, L-lactic acid (D, L-LA) catalyzed by 0.5% (percent of weight) of SnCl2, at 165°C and under 70 Pa, a series of biodegradable material poly (glycolic acid-lactic acid) from different molecular feed ratio were directly synthesized via 10 hours' melt polycondensation. The series of D, L-PGLA were characterized by using GPC, FT-IR, 1HNMR, DSC and XRD. When n (GA): n (D, L-LA) = 1:1, the weight-average relative molecular weight (Mw) of D,L-PGLA 50/50 is 24300, which is higher than that of L-PGLA 50/50 (Mw = 18000) under the same synthetic condition.