丙交酯与聚乳酸的合成

Synthesis of Lactide and Polylactic acid

以D,L-乳酸为单体,氧化锌为催化剂,将乳酸合成D,L丙交酯;再以辛酸亚锡为催化剂,使丙交酯单体开环聚合制备聚乳酸。结果表明,乳酸在130℃、氧化锌质量分数为1.1%时,其粗产品产率大于60%;丙交酯聚合时,辛酸亚锡用量为0.02 mL时,聚合温度为160℃,常压聚合5 h即可得到粘均分子质量为6.0×104的聚乳酸;测试结果表明丙交酯在辛酸亚锡作用下发生了开环反应。

Lactide was synthetized by emulsion method using D,L-lactic acid as monomer and zinc oxide as catalyst, and polylactic acid was prepared by the ring-opening polymerization of lactide mooome with starmous octoate as catalyst. The results show that the yield of lacitc acid is greater than 60% when the temperture is 130 ℃ and the mass fraction of zinc oxide is 1.1%. Under the conditions of dosage of stanous octoat 0.02 mL, temperture 160 ℃ and reaction time 5 h, lactide can be polymerized into polylactic acid with the viscosity average molecular weight of 6.0 ~ 104. The results indicate that ring-opening reaction of lactide has happened using stannous octoate as catalyst.