Synthesize,Characterization And Copolymerization Of L-lactide

In this paper, firstly lactide, glycollide and their copolymer(PGLA) were summarized, primarily involved their basal performance, method of their synthesize, actuality of their development.In this paper, synthesize of lactide, glycollide and their copolymer was primarily studied and the properties of lactide, glycollide and their copolyme were characterized by IR, NMR, GPC, TG-DTA, DSC . Lactide was synthesized by lactic acid, glycollide was synthesized by glycolic acid and PGLA was synthesized by lactide and glycollide. The quadruply orthogonal experiment method was used to study how catalyst, temperature and time affected the percentage yield of lactide, glycollide, PGLA and the molecular weight of PGLA, finally get the most optimized condition. Stannous octoate was selected as catalyst and testified the catalyst was the most appropriate. When catalyst was 1.5ml, dehydrated temperature was 135℃, decomposition temperature was 195℃, the percentage yield of lactide was 82.5%. When catalyst was 4.5ml, dehydrated temperature was 145℃, decomposition temperature was 250℃, the percentage yield of glycolide was 72.7%. When catalyst (sherwood oile was used to dissolve stannous octoate and get liquor which concentration was 0.00001 mol/ml) was 1ml, temperature was 165℃, time was 5h, the percentage yield of PGLA was 79.5%. When catalyst was lml, temperature was 170°C, time was 6h, the molecular weight of PGLA was 9.16× 10~4.