Zhan Rui, Li Xing-Liang, Zheng Yu, Zeng Xin-Rong, Shi Ling-Ying, Yang Ke-Ke, Wang Yu-Zhong
The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu 610064, China.
College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
Int J Biol Macromol. 2025 Apr;302:140530. doi: 10.1016/j.ijbiomac.2025.140530. Epub 2025 Jan 30.
Developing biodegradable polymers with superior mechanical performance offers a sustainable solution to address the severe environmental challenges posed by conventional plastics. Poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT), two prominent biodegradable plastics, exhibit complementary mechanical properties. However, their inherent incompatibility and significant viscosity mismatch cause significant challenges for effective blending via the conventional methods. Herein, we propose an innovative strategy that integrates kinetic and thermodynamic principles to fabricate PLA/PBAT composites with high strength and high toughness. An adaptable ternary copolymer, presenting strong affinity with both PLA and PBAT segments, was employed as an epoxy chain extender (EE) to covalently couple PLA and PBAT under high shear conditions. The high-shear reactor reduced the size of the dispersed phase and significantly expanded interface area, providing abundant reaction sites for EE. This enabled the in-situ generation of abundant PLA-PBAT copolymers, as evidenced by increased melt viscosities and higher molecular weight of the resulting products. By optimizing the EE content to 2.5 wt%, PLA/PBAT composite achieved an exceptional balance between strength (47.6 MPa) and toughness (229.3 MJ/m), representing improvements of 47 % and 34-fold, respectively, over conventional PLA/PBAT blend. This work provides a scalable and robust platform for developing high-performance biodegradable composites from immiscible polymers.
开发具有卓越机械性能的可生物降解聚合物，为应对传统塑料带来的严峻环境挑战提供了一种可持续的解决方案。聚乳酸（PLA）和聚己二酸-对苯二甲酸丁二醇酯（PBAT）这两种著名的可生物降解塑料，展现出互补的机械性能。然而，它们固有的不相容性以及显著的粘度不匹配，给通过传统方法进行有效共混带来了重大挑战。在此，我们提出一种创新策略，该策略整合动力学和热力学原理，以制备具有高强度和高韧性的PLA/PBAT复合材料。一种与PLA和PBAT链段均具有强亲和力的适应性三元共聚物，被用作环氧扩链剂（EE），在高剪切条件下将PLA和PBAT共价偶联。高剪切反应器减小了分散相的尺寸并显著扩大了界面面积，为EE提供了丰富的反应位点。这使得能够原位生成大量的PLA-PBAT共聚物，所得产物的熔体粘度增加和分子量提高证明了这一点。通过将EE含量优化至2.5 wt%，PLA/PBAT复合材料在强度（47.6 MPa）和韧性（229.3 MJ/m）之间实现了出色的平衡，分别比传统PLA/PBAT共混物提高了47%和34倍。这项工作为从不相容聚合物开发高性能可生物降解复合材料提供了一个可扩展且稳健的平台。
