Stereocomplex Crystallization Induced Significant Improvement in Transparency and Stiffness-Toughness Performance of Core-Shell Rubber Nanoparticles Toughened Poly(l-lactide) Blends
Stereocomplex Crystallization Induced Significant Improvement in Transparency and Stiffness-Toughness Performance of Core-Shell Rubber Nanoparticles Toughened Poly(l-lactide) Blends
复制标题
立体络合物结晶导致核壳橡胶纳米粒子增韧聚（l-丙交酯）共混物的透明度和刚度-韧性性能显着改善
DOI：
10.1002/mame.202100021
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发表时间：
2021-02-22
影响因子：
3.9
通讯作者：
Fu, Qiang
中科院分区：
文献类型：
--
作者：
Liu, Huili;Bai, Dongyu;Fu, Qiang
橡胶粒子对聚L-丙交酯(PLLA)的增韧改性通常是以牺牲透明度、机械强度和弹性模量为代价的，因为增韧通常需要较高的橡胶载量。在这项工作中，利用PLLA和聚乳酸(PDLA)之间的立体络合物(SC)结晶，设计了一种同时提高聚丙烯酸丁酯-聚甲基丙烯酸甲酯(BAMMA)核-壳橡胶纳米粒子增韧PLLA共混物透明度和刚性韧性的策略。结果表明，PLLA/BAMMA共混物与PDLA熔融共混，在PLLA基质中构建SC微晶，可以阻止BAMMA纳米粒子的团聚，促进其在较低含量下形成网状结构。结果表明，与PLLA/BAMMA共混物相比，PLLA/PDLA/BAMMA共混物不仅具有较高的增韧效率，而且橡胶含量较少，且透明性较好。此外，SC微晶网络对PLLA的显著增强作用可以提高PLLA/PDLA/BAMMA共混物的拉伸强度和弹性模量，从而在较大程度上改善PLLA/PDLA/BAMMA共混物的刚性-韧性性能。研究表明，SC结晶是解决橡胶增韧PLLA共混物透明性与力学性能之间矛盾，进而获得优异综合性能的一种很有前途的解决方案。
Toughening modification of poly(l-lactide) (PLLA) with rubber particles is often realized at the cost of transparency, mechanical strength, and modulus because high rubber loadings are generally required for toughening. In this work, a promising strategy to simultaneously improve the transparency and stiffness-toughness performance of poly(butyl acrylate)-poly(methyl methacrylate) (BAMMA) core-shell rubber nanoparticles toughened PLLA blends by utilizing the stereocomplex (SC) crystallization between PLLA and poly(d-lactide) (PDLA) is devised. The results reveal that the construction of SC crystallites in PLLA matrix via melt-mixing PLLA/BAMMA blends with PDLA can prevent BAMMA nanoparticles from aggregation and promote them to form network-like structure at lower contents. As a result, not only higher toughening efficiency with less rubber contents but also superior transparency is achieved in the PLLA/PDLA/BAMMA blends as compared with the PLLA/BAMMA ones where large aggregated BAMMA clusters are formed. Moreover, the outstanding reinforcement of SC crystallites network for PLLA can impart an enhanced tensile strength and modulus to PLLA/PDLA/BAMMA blends, thus improving the stiffness-toughness performance of PLLA/PDLA/BAMMA blends to a higher degree. This work demonstrates that SC crystallization is a promising solution to solve the contradiction between transparency and mechanical properties and then obtain superior comprehensive performances in rubber toughened PLLA blends.