Guo Zhenbo, Zhang Haoran, Chen Haoyu, Zhang Meiqi, Tang Xiaoyan, Wang Meng, Ma Ding
Beijing National Laboratory for Molecular Sciences, New Cornerstone Science Laboratory, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.
Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center for Soft Matter Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
Angew Chem Int Ed Engl. 2025 Feb 3;64(6):e202418157. doi: 10.1002/anie.202418157. Epub 2024 Nov 21.
The recycling and upcycling of polyethylene terephthalate (PET), the most widely used polyester plastic globally, has attracted growing attention concerning its disposal as non-degradable waste in the natural environment. Transforming end-of-life PET into (bio)degradable polyester offers a novel approach to managing its waste. In this study, we introduce a simple process capable of converting waste PET into degradable polyester, polyethylene terephthalate-polyethylene-1,4-cyclohexanedicarboxylate (PET-PECHD), by partly hydrogenating the aromatic rings (x) into aliphatic ones (y). The polyesters with variable x/y compositions ranging from 100/0 to 0/100 can be achieved, and the molecular weight (Mw) can be maintained when x/y >87/13 due to the nonobvious depolymerization. Pronounced depolymerization would occur with deeper hydrogenation, which generates a blend of PET-PECHD and polyethylene-1,4-cyclohexanedicarboxylate (PECHD) with lower Mw, and finally a single-type polymer PECHD. The PET-PECHD demonstrates comparable thermal stability and mechanical strength compared to PET, along with superior extensibility, barrier properties, and (bio)degradability in acidic, alkaline solutions, and moist soil. This research highlights the potential for cost-effective, large-scale production of degradable polyester from real-life plastic waste.
聚对苯二甲酸乙二酯（PET）是全球使用最广泛的聚酯塑料，其回收和升级回收越来越受到关注，因为它在自然环境中作为不可降解废物进行处理。将废弃PET转化为（可）降解聚酯为管理其废物提供了一种新方法。在本研究中，我们介绍了一种简单的工艺，能够通过将芳香环（x）部分氢化为脂肪族环（y），将废弃PET转化为可降解聚酯聚对苯二甲酸乙二酯-聚-1,4-环己烷二甲酸乙二酯（PET-PECHD）。可以实现x/y组成从100/0到0/100变化的聚酯，并且当x/y>87/13时，由于解聚不明显，分子量（Mw）可以保持。深度氢化会发生明显的解聚，生成Mw较低的PET-PECHD和聚-1,4-环己烷二甲酸乙二酯（PECHD）的混合物，最终生成单一类型的聚合物PECHD。PET-PECHD与PET相比具有相当的热稳定性和机械强度，同时在酸性、碱性溶液和潮湿土壤中具有优异的延展性、阻隔性能和（生物）降解性。本研究突出了从实际塑料废物中经济高效地大规模生产可降解聚酯的潜力。
