聚乳酸/聚氨酯复合材料的制备及性能研究

目的 以聚乳酸(PLA)为基材，制备聚乳酸/聚氨酯(TPU)复合材料，并研究复合材料的性能和TPU含量对复合材料的影响。方法 利用双螺旋杆挤出机将PLA和TPU熔融共混后挤出，得到含不同质量分数TPU(17%、20%、25%、33%、50%)的复合材料，对复合材料进行红外分析，测试不同含量TPU对其热稳定性能、动态热力学性能和流变特性的影响。结果 随着TPU含量的增加，复合材料的热稳定性能和韧性变好;在流变实验中复合材料表现出剪切变稀的特点，且TPU质量分数为33%时复合材料所表现出的各项性能最优。结论 TPU的加入可以改善PLA脆性大、韧性小的缺陷，并获得热力学性质稳定、兼具2种材料的优势并且具有环境友好性的复合材料。

Preparation and Properties of PLA/TPU Composites

The work aims to prepare polylactic acid (PLA)/thermoplastic polyurethane (TPU) composites with PLA as substrate to study the properties of composites and the effect of TPU content on it. Composites with different concentrations (17%, 20%, 25%, 33%and 50%) were prepared by blending of PLA and TPU with a twin-screw extruder. Infrared analysis of the composites were conducted and the effects of TPU on thermostabilities, thermodynamic properties and rheological properties of the composites were studied. With the increase of TPU, the thermostability and ductility improved;in the rheological experiment, the composites showed shear thinning and the properties of the composite were the best when the TPU content was 33%. The results show that the performance of PLA is improved after the addition of TPU.Composites can obtain the advantages of both materials without losing environmentally friendly.