乳酸膨润土及其在聚乳酸材料中的应用

Lactate-Ca-bentonite and its application in poly(lactic acid) materials

为扩展聚乳酸的应用范围,用乳酸与碱性钙基膨润土反应制备出剥离型乳酸膨润土,并用该材料与聚乳酸通过氯仿溶液铸膜法制备出聚乳酸/乳酸膨润土复合膜。用扫描电镜(SEM)观察膜的形态,万能力学试验机测定膜的拉伸强度和断裂伸长率,差示扫描量热法(DSC)和热重分析(TGA)研究膜的热性能。测试结果表明,添加1%的乳酸膨润土以剥离片层分散在聚乳酸基体中,可使复合膜的拉伸强度和断裂伸长率分别提高24%和55%,复合膜的透明性和使用温度基本不受影响,热分解温度降低25℃。

In order to extend the application of poly（lactic acid）（PLA）,exfoliated lactate-Ca-bentonite materials were prepared by the reaction of alkaline Ca-bentonite with lactic acid.The composite films of PLA with various amounts of the lactate-Ca-bentonite were prepared by solution casting using chloroform as solvent.The morphology of the films was observed by scanning electron microscope（SEM）.Tensile strength and elongation at break of the films were investigated by the electronic universal material testing machine.The thermal properties of the films were tested by the differential scanning calorimeter（DSC） and the thermogravimetric analyzer（TGA）.The results indicated that the tensile strength and elongation of the composite films at break increased to 24% and 55% compared to the pure PLA film respectively with the addition of 1% of the exfoliated lactate-Ca-bentonite.And the optical transparency and the range of operating temperature of the film were hardly affected while its thermal degradation temperature（TD） declined by 25 ℃.