近日，东北师范大学刘东涛团队实现了利用有机催化剂的氟化策略获得化学上可回收的高分子量聚（1,3-二恶烷）。2026年3月24日出版的《中国化学》杂志发表了这一最新研究成果。

循环经济已成为全球塑料工业实现可持续发展的关键且不可逆转的未来方向，旨在缓解传统不可降解塑料所造成的严重环境污染与资源浪费问题。化学回收至单体（CRM）技术可将废弃聚合物直接转化为单体，为实现塑料循环经济提供了一条极具前景的途径。聚1,3-二氧戊环（PDXL）因其优异的化学可回收性、出色的耐热性及良好的机械性能，是一种理想的CRM用热塑性塑料，有望成为商业化石油基聚烯烃塑料的有力替代品。

研究组利用全氟三苯基硼烷（B(C₆F₅)₃）成功实现了1,3-二氧戊环（DXL）的高效开环聚合，以高活性制备了PDXL；而在相同反应条件下，非氟化类似物三苯基硼烷（BPh₃）对DXL聚合则呈惰性。在单体与催化剂比例为700:1时，所制备的PDXL数均分子量高达178 kDa，5%热分解温度达356 °C，具有优异的热稳定性，且拉伸强度（σ_B = 30 MPa）远超传统商用聚乙烯材料。值得注意的是，研究组通过B(C₆F₅)₃与DXL的等摩尔反应，首次分离出聚合反应中的关键活性物种，并利用核磁共振（NMR）波谱及单晶X射线衍射分析对其进行了全面表征。

基于该活性物种的晶体结构，结合密度泛函理论（DFT）模拟，提出了DXL开环聚合的详细机理并加以证实。此外，以磷钨酸（PTA）为催化剂，即使在颜料添加剂或混合塑料废物存在下，也能以高转化率获得高纯度DXL单体，实现了PDXL的化学回收。PTA可在解聚过程中被回收并重复使用。研究组为无金属催化剂介导的化学可回收聚合物制备提供了一种可行且高效的策略，推动了循环塑料的发展。

附：英文原文

Title: Chemically Recyclable Poly(1,3-dioxolane) with High Molecular Weight Achieved Using a Fluorinated Strategy of Organocatalyst

Author: Dan Liu, Jingyuan Zhao, Ting Xi, Boyan Tang, Peng Zhang, Xinlu Wang, Dongtao Liu

Issue&Volume: 2026-03-24

Abstract: The circular economy has emerged as a pivotal and irreversible future direction for the sustainable development of the global plastics industry, aiming to alleviate the severe environmental pollution and resource waste caused by traditional non-degradable plastics. Chemical recycling to monomers (CRM) converts waste polymers directly back to monomers, offering a highly promising approach to enabling a circular plastics economy. Poly(1,3-dioxolane) (PDXL) is an ideal thermoplastic for CRM owing to its excellent chemical recoverability, outstanding thermal resistance, and robust mechanical properties, making it a competitive alternative to commercial petroleum-based polyolefin plastics. In this work, high-efficiency ring-opening polymerization of 1,3-dioxolane (DXL) to prepare PDXL was successfully achieved in high activity using perfluorinated triphenylborane (B(C6F5)3), while the unfluorinated analogue triphenylborane (BPh3) is inert to the polymerization of DXL under identical reaction conditions. The as-prepared PDXL features a high number-average molecular weight of 178 kDa at a monomer-to-catalyst ratio ([DXL]/[B(C6F5)3]) of 700 : 1, excellent thermal stability with 5% thermal decomposition temperature of 356 °C, and superior tensile strength (σB =30 MPa), which far exceeds that of conventional commercial polyethylene materials. Significantly, the key active species involved in the polymerization process was isolated for the first time via equimolar reaction of B(C6F5)3 with DXL, and thoroughly characterized by nuclear magnetic resonance (NMR) spectroscopy and single-crystal X-ray diffraction analysis. Based on the crystal structure of active species, the detailed mechanism of the ring-opening polymerization of DXL has been proposed and confirmed through density functional theory (DFT) simulations. Furthermore, chemical recyclability of PDXL was accomplished using phosphotungstic acid (PTA) as a catalyst, yielding high-purity DXL monomer with high conversion, even in the presence of pigment additives or mixed plastic waste. PTA can be recovered and reused repeatedly for the depolymerization process. This work offers a feasible and efficient strategy for metal-free catalyst-mediated preparation of chemically recyclable polymers, promoting the advancement of circular plastics.

DOI: 10.1002/cjoc.70557

Source: https://onlinelibrary.wiley.com/doi/10.1002/cjoc.70557