聚丁二酸丁二醇酯与氯醚弹性体协同增韧改性聚乳酸多元共混体系

以来源于可再生资源聚丁二酸丁二醇酯(PBS)和氯醚橡胶(ECO)作为聚乳酸(PLA)的增韧改性剂,通过熔融共混的方法制备了PLA/PBS/ECO三元共混体系。动态力学分析和扫描电子显微镜结果表明,ECO促进了PBS和PLA之间的相容性。力学性能测试表明,ECO与PBS可实现对聚乳酸基体的协同增韧: PLA/PBS/ECO(70/20/10)显示出最优的拉伸性能,断裂伸长率高达270%;PLA/PBS/ECO(70/10/20)的冲击强度提高至23.7 kJ/m²,是纯聚乳酸的12倍。结合形态结构和冲击断面形貌分析表明ECO的存在可起到增容/增韧双重作用, 与柔性PBS产生良好的协同效应,有效改善聚乳酸材料的韧性。我们的研究表明,构造PLA-柔性生物聚酯和生物基弹性体多元共混体系是一种获得高性能生物基材料简单高效的手段。

Synergetic Modification of Polybutylene Succinate and Poly(epichlorohydrin-co-ethylene oxide) Elastomer in Toughening Poly(lactic acid)

A ternary blend system was prepared via melt blending poly(lactic acid)(PLA) with renewable poly(butylene succinate)(PBS) and poly(epichlorohydrin-co-ethylene oxide) copolymer(ECO) to toughen PLA. The results of dynamic mechanical analysis(DMA) and scanning electron microscopy(SEM) showed that the ECO component improved the miscibility between PBS and PLA. The mechanical test proved that ECO and PBS could synergistically toughen the PLA matrix. The highest elongation at break was 280% for PLA/PBS/ECO(70/20/10) while the impact strength of PLA/PBS/ECO(70/10/20) blend was up to 23.7 kJ/m² which is 12 times as much as that of neat PLA. In the ternary blend, ECO plays a dual role as both the compatibilizer and the toughening agent, resulting in a favorable synergistic effect with PBS. Blending PLA with flexible biopolyester and bioelastomer is proved to be a simple and efficient way to obtain high performance biobased materials.