高岭土改性聚乳酸基复合材料的制备及性能

Preparation and properties of polylactide composite modified by kaolin

以丙交酯为原料、以丁二酸酐为亲水改性剂,共聚合成了较低分子量的端羧基聚乳酸P(LA/SA)预聚体;再以二甲亚砜复合改性的高岭土为层状主体、以P(LA/SA)为插入客体、以二噁唑啉(1,3-PBO)为扩链剂,采用原位聚合法合成了高岭土改性聚乳酸基复合材料.使用GPC、FT-IR、DSC、SEM等测试手段对改性聚乳酸和复合改性材料的性能及结构进行了表征.FT-IR数据表明1,3-PBO对端羧基聚乳酸成功扩链生成了目标产物PLEA;SEM形貌表征结果表明PLEA与高岭土形成了插层复合材料.最终确定当m(P(LA/SA))∶m(高岭土/二甲亚砜)为1.2、聚合温度为160℃、反应时间为12h时,其合成的高岭土/PLEA复合材料的性能得到了明显提升,经过高岭土改性的高岭土/PLEA复合材料的耐热性亦得到了提高.

Firstly ,the low molecular weight polylactic acid P （LA/SA ） was synthesized via lactide as the raw material and succinic anhydride as the hydrophilic modification .Then ,the kaolin modified polylactic acid based composite material was prepared by 2‐oxazoline （1 ,3‐PBO） as a chain extender with dimethyl sulfoxide composite modified kaolin as the main body in the stratified and P（LA/SA） as the object of insert by using in situ polymerization . The structure were characterized by FT‐IR and the properties were investigated by GPC , DSC ,SEM .The FT‐IR result show that 1 ,3‐PBO successful chain terminal carboxyl group of polylactic acid to generate the target product PLEA .The SEM result show that PLEA with kaolin intercalated composite material .Finally confirmed that when the ratio of the m（P（LA/SA））∶ m（Kaolin/dimethyl sulfoxide）is 1 .2 ,the polymerization temperature is 160 ℃ ,the reaction time is 12 h ,the kaolin/PLEA composites performance is improved obviously ,after the kaolin modified kaolin/PLEA complex heat resistance was improved ,enhanced tough‐ness .