聚乳酸在挤出过程中的降解  

Degradation of Poly Lactic Acid during Extrusion

作　　者：刘勇[1] 王庆海[1] 李静[1] 

机构地区：[1]华东理工大学材料科学与工程学院超细材料制备与应用教育部重点实验室,上海200237

出　　处：《塑料》2011年第3期71-72,18,共3页Plastics

摘　　要：以真空干燥后的聚乳酸(PLA)为实验原料,分别在料筒温度为170、190℃条件下进行挤出研究。主要研究挤出温度、螺杆转速对聚乳酸分子量的影响。结果表明:烘干后PLA分子力降低的主要原因是在挤出机内受剪切力后发生了力化学降解。随着螺杆转速的提高,剪切力增大分子量随之降低。挤出后的聚乳酸分子量在降低的同时,分子量分布也有所变小。The extrusion was tested when the barrel temperature was 170 and 190 ℃ ,using the material of vacuum dried PLA. The temperature of the extrusion and screw were the main factor for the PLA molecular weight. The result showed that the decreasement of vacuum dried PLA was driven by the shear in the extruder and then the chemical degradation. The molecular weight distribution was narrowed when the situation of molecular weight decreasing was happening. Shear was increased and then the molecular weight lessen, when the revolution speed was increased.

关 键 词：聚乳酸 挤出成型 分子量 降解 剪切 

分 类 号：Q946.816[生物学—植物学]