近日，天津大学王彬团队通过缩聚-解聚-再聚合策略模块化获得具有可调性能和双闭环可回收性的脂肪族聚碳酸酯。该项研究成果发表在2025年4月28日出版的《德国应用化学》上。

人们在CO₂/环氧化物共聚和碳酸二烷基酯/二醇缩聚方面取得了巨大成就，然而，在温和条件下高效制备具有可调性能和可回收性的高分子量（>100kDa）脂肪族聚碳酸酯仍然是一个巨大的挑战。研究组提出了一种针对结构多样的脂肪族聚碳酸酯的“缩聚-解聚-再聚合”策略。这涉及碳酸二烷基酯和二醇在大气压下逐步生长缩聚为低分子量（0.5-1.9 kDa）聚碳酸酯，然后通过催化解聚制备环状碳酸酯单体。 

环状碳酸酯的开环聚合导致高分子量（>100kDa）聚合物，其可以通过闭环解聚转化回环状单体，或通过醇解转化回二醇/碳酸二烷基酯，从而使聚碳酸酯能够通过双闭环进行化学循环。聚碳酸酯的热和机械性能可以通过改变取代基进行广泛调节，具有四元螺环取代基的聚碳酸酯在报告的聚碳酸酯家族中显示出记录的高熔融温度（217°C）和机械强度。通过顺序聚合还制备了具有良好机械性能和弹性恢复的A（硬）-B（软）-A（硬）三嵌段热塑性弹性体。“缩聚-解聚-再聚合”策略为开发高性能脂肪族聚碳酸酯提供了强大的工具箱。

附：英文原文

Title: Modular access to aliphatic polycarbonates with tunable properties and dual closed-loop recyclability by polycondensation−depolymerization−repolymerization strategy

Author: Bin Wang, Wei-Ning Liu, Mingqian Wang, Zhiqiang Ding, Yuesheng Li

Issue&Volume: 2025-04-28

Abstract: Great achievements have been made in CO2/epoxide copolymerization and dialkyl carbonate/diol polycondensation, however, efficient preparation of high-molecular-weight (> 100 kDa) aliphatic polycarbonates with tunable properties and recyclability under mild conditions still remain as a great challenge. Herein, we presented a “polycondensationdepolymerizationrepolymerization” strategy for structurally diverse aliphatic polycarbonates. This involved a step growth polycondensation of dialkyl carbonate and diol to low-molecular-weight (0.5 1.9 kDa) polycarbonates under atmosphere pressure, which are then utilized to produce cyclic carbonate monomers through catalytic depolymerization. The ring-opening polymerization of cyclic carbonate led to high molecular weight (> 100 kDa) polymers, which can be converted back to cyclic monomer via ring-closing depolymerization or diol/dialkyl carbonate via alcoholysis, enabling chemical recycling of polycarbonates via dual closed loops. The thermal and mechanical properties of the polycarbonates can be widely adjusted by varying the substituent, and polycarbonate with four-membered spiro-cyclic substituent shows a recorded high melting temperature (217 °C) and mechanical strength within the reported polycarbonate family. A(hard)-B(soft)-A(hard) triblock thermoplastic elastomers with good mechanical performance and elastic recovery were also created by sequential polymerization. The “polycondensationdepolymerizationrepolymerization” strategy provided a powerful toolbox for developing high-performance aliphatic polycarbonates.

DOI: 10.1002/anie.202505333

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202505333