Shanxi Engineering Research Center of Biorefinery, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan 030001, China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China; CAS Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan 030001, China.
Institute of Interface Chemistry and Engineering, Department of Chemistry and Chemical Engineering, Taiyuan Institute of Technology, Taiyuan, Shanxi 030008, China.
Waste Manag. 2023 Jan 1;155:260-268. doi: 10.1016/j.wasman.2022.11.010. Epub 2022 Nov 16.
Vinyl ester resins (VER) and its composites are widely used in chemical industry and municipal engineering. However, its dense three-dimensional network structure makes its degradation and recycling a great challenge. Herein, a novel, efficient and green degradation system gamma-valerolactone (GVL)-HO/p-toluene sulfonic (PTSA) was developed to degrade VER and its composites. VER was completely degraded in the GVL-HO/PTSA at 210 °C and 0.6 MPa. By combing SEM-EDS, IR, NMR, GPC and MALDI-TOF-MS analysis, it was clarified that VER swelled well in GVL, allowing the transfer of PTSA and HO through the resin matrix. The ester bonds in VER were cleaved via hydrolysis with HO catalyzed by the sulfonic acid of PTSA, and high value-added polymer products, i.e., copolymer of styrene and methacrylic acid (SMAA) and bisphenol-A diglycidyl ether (DGEBA), were recycled, which accounted for ca. 87.0 wt% of raw VER. DGEBA can be recycled to prepare a new PU material. The GVL-HO/PTSA system was also effective for degrading UPR and VER-containing composites. This work provides a practical strategy for chemical degradation and recovery of thermoset VER resins.
乙烯基酯树脂（VER）及其复合材料广泛应用于化学工业和市政工程。然而，其致密的三维网络结构使其降解和回收成为一大挑战。在此，开发了一种新型、高效、绿色的降解体系γ-戊内酯（GVL）-HO/对甲苯磺酸（PTSA），用于降解 VER 及其复合材料。在 210°C 和 0.6MPa 的 GVL-HO/PTSA 中，VER 完全降解。通过 SEM-EDS、IR、NMR、GPC 和 MALDI-TOF-MS 分析，阐明了 VER 在 GVL 中很好地溶胀，允许 PTSA 和 HO 通过树脂基体传递。VER 中的酯键通过 HO 催化 PTSA 的磺酸的水解断裂，回收了高附加值的聚合物产物，即苯乙烯和甲基丙烯酸的共聚物（SMAA）和双酚 A 二缩水甘油醚（DGEBA），占原始 VER 的约 87.0wt%。DGEBA 可回收用于制备新型 PU 材料。GVL-HO/PTSA 体系也可有效降解 UPR 和含 VER 的复合材料。这项工作为热固性 VER 树脂的化学降解和回收提供了实用策略。
