J Am Chem Soc. 2021 Sep 29;143(38):15784-15790. doi: 10.1021/jacs.1c07229. Epub 2021 Sep 16.
Polyesters constitute nearly 10% of the global plastic market, but most are essentially non-degradable under ambient conditions or in engineered environments. A range of degradable polyesters have been developed as more sustainable alternatives; however, limitations of practical degradability and scalability have hindered their viability. Here, we utilized transesterification approaches, including polymerization-transesterification, between a salicylate and a polyester to incorporate salicylate units into commercial polyester backbones. The strategy is scalable and practically relevant given that high molar mass polymers can be obtained from melt-processing of commercial polyesters using common compounders or extruders. Polylactide containing sparse salicylate moieties shows enhanced hydrolytic degradability in aqueous buffer, seawater, and alkaline solutions without sacrificing the thermal, mechanical, and O barrier properties of the parent material. Additionally, salicylate sequences were incorporated into polycaprolactone and a derivative of poly(ethylene terephthalate), and those modified polymers also exhibited facile degradation behavior in alkaline solution, further expanding the scope of this approach. This work provides insights and direction for the development of high-performance yet more sustainable and degradable alternatives to conventional polyesters.
聚酯占全球塑料市场的近 10%,但在环境条件或工程环境下,大多数聚酯基本上是不可降解的。已经开发出一系列可降解的聚酯作为更可持续的替代品;然而,实际可降解性和可扩展性的限制阻碍了它们的可行性。在这里,我们利用了酯交换方法,包括水杨酸盐和聚酯之间的聚合-酯交换,将水杨酸盐单元引入商业聚酯主链中。该策略具有可扩展性和实际相关性,因为可以通过使用普通化合物或挤出机对商业聚酯进行熔融加工来获得高摩尔质量的聚合物。含有稀疏水杨酸盐部分的聚乳酸在水性缓冲液、海水和碱性溶液中表现出增强的水解降解性,同时不牺牲母体材料的热、机械和 O 阻隔性能。此外,水杨酸盐序列被引入聚己内酯和聚对苯二甲酸乙二醇酯的衍生物中,这些改性聚合物在碱性溶液中也表现出易于降解的行为,进一步扩展了这种方法的范围。这项工作为开发高性能但更可持续和可降解的传统聚酯替代品提供了思路和方向。