Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore, 117575, Singapore.
School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore, 639798, Singapore.
Macromol Rapid Commun. 2022 Jan;43(2):e2100619. doi: 10.1002/marc.202100619. Epub 2021 Nov 1.
Bio-based and biodegradable polymer composites, most notably poly(l-lactic acid) (PLLA) and poly(3-hydroxybutyrate) (PHB), represent a promising solution to replace conventional petroleum-based plastics. However, the brittleness and low miscibility of PLLA and PHB remain two major obstacles to practical applications. In this work, first PLLA/PHB blends are reported by melt mixing with a rigid component, poly(methyl methacrylate) (PMMA). Driven by favorable entropy, PMMA forms an interfacial nanolayer, which transforms the morphology of resultant blends. The ternary blends show 55-fold increase in elongation, 50-fold in toughness, and metal-like malleability (≈180° bending and twisting), while retaining its high stiffness (3.4 GPa) and strength (≈50 MPa). The mechanical improvement arises from numerous craze fibrils and shear deformation of the matrix, induced by the incorporated PMMA. Furthermore, this generic strategy can be applied to design other mechanically robust biocomposites for advanced green devices.
基于生物的和可生物降解的聚合物复合材料，尤其是聚（L-乳酸）（PLLA）和聚（3-羟基丁酸酯）（PHB），代表了一种有前途的解决方案，可以替代传统的基于石油的塑料。然而，PLLA 和 PHB 的脆性和低混溶性仍然是实际应用的两个主要障碍。在这项工作中，首先通过熔融混合报告了 PLLA/PHB 共混物，其中刚性组分是聚甲基丙烯酸甲酯（PMMA）。受有利熵的驱动，PMMA 形成了界面纳米层，从而改变了所得共混物的形态。三元共混物的伸长率增加了 55 倍，韧性增加了 50 倍，延展性类似于金属（≈180°弯曲和扭曲），同时保持了其高刚度（3.4 GPa）和强度（≈50 MPa）。机械性能的提高源于掺入的 PMMA 诱导的大量银纹纤维和基体的剪切变形。此外，这种通用策略可用于设计其他用于先进绿色设备的机械坚固的生物复合材料。
