Zhang Xun, Feng Ximin, Guo Wenqi, Zhang Chengjian, Zhang Xinghong
State Key Laboratory of Biobased Transportation Fuel Technology, International Research Center for X Polymers, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
Nat Commun. 2024 Oct 2;15(1):8536. doi: 10.1038/s41467-024-52852-y.
Polyvinyl chloride (PVC) is the world's third-most widely manufactured thermoplastic, but has the lowest recycling rate. The development of PVC-like plastics that can be depolymerized back to monomer contributes to a circular plastic economy, but has not been accessed. Here, we develop a series of chemically recyclable plastics from the reversible copolymerization of cyclic anhydride with chloral. The copolymerization is highly efficient through the anionic or cationic mechanism under mild conditions, yielding polyesters with tunable structure and properties from multiple commercial monomers. Notably, these polyesters manifest mechanical properties comparable to PVC and polystyrene. Meanwhile, such polyesters are flame-retardant like PVC due to high chloride content. Of significance, these polyesters can be depolymerized back to starting monomers at high temperatures owing to the reversibility of the copolymerization, leading to a circular economy. Overall, the readily available monomers, simple synthesis, advantageous performance, and practical recyclability make the polymers promising for applications.
聚氯乙烯（PVC）是世界上产量第三高的热塑性塑料，但回收率却最低。开发能够解聚回单体的类聚氯乙烯塑料有助于实现循环塑料经济，但尚未实现。在此，我们通过环状酸酐与氯醛的可逆共聚反应开发了一系列可化学回收的塑料。该共聚反应在温和条件下通过阴离子或阳离子机理高效进行，从多种商业单体中制得结构和性能可调的聚酯。值得注意的是，这些聚酯表现出与聚氯乙烯和聚苯乙烯相当的机械性能。同时，由于高氯含量，此类聚酯像聚氯乙烯一样具有阻燃性。重要的是，由于共聚反应的可逆性，这些聚酯在高温下可解聚回起始单体，从而实现循环经济。总体而言，这些聚合物具有易于获得的单体、简单的合成方法、优异的性能和实际的可回收性，具有广阔的应用前景。
