清华大学唐黎明团队报道了承载受阻尿素键的紫外光固化可再加工热固性材料，及其改性氧化锌纳米颗粒复合材料的研究。相关研究成果发表在2024年4月16日出版的《中国高分子科学杂志》。

该研究以甲基丙烯酸异冰片酯为反应稀释剂，采用一锅法制备了一系列含有受阻脲键（HUB）的聚氨酯-甲基丙烯酸脲预聚物，和一种不含受阻脲键的聚氨酯-丙烯酸酯预聚物。通过各种技术对预聚物进行了充分的表征。然后，在光引发剂存在下，通过紫外线固化制备了它们的热固性材料，并对它们的力学性能和热行为进行了研究和比较。与不含HUB的热固性材料不同，含HUB热固性材料（定义为PUT）可以在相对温和的条件下通过热压回收和再加工，具有较高的机械性能回收率。

此外，用甲基丙烯酸3-（三甲氧基甲硅烷基）丙酯对氧化锌（ZnO）纳米颗粒进行改性，并将改性的ZnO（定义为ZnO-TPM）分散聚合到PUT基体中，制备其纳米复合材料。评价了ZnO-TPM对复合材料力学性能的影响，结果表明，当ZnO-TPM含量为1wt%时，复合材料的杨氏模量和拉伸强度逐渐增加到最大值，然后降低。与纯PUT样品相比，该复合材料还显示出良好的可再加工性和更高的回收率。此外，复合材料表现出较强的紫外线吸收能力，这意味着它们在需要紫外线屏蔽的环境中具有潜在的应用前景。

附：英文原文

Title: Investigation on UV-curing Reprocessable Thermosets Bearing Hindered Urea Bonds and Their Composites with Modified Zinc Oxide Nanoparticles

Author: Jun-Hao Zhou, Li-Ming Tang

Issue&Volume: 2024-04-16

Abstract: In this study, a series of hindered urea bond (HUB) containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot procedure. The prepolymers were characterized fully by various techniques. Then, their thermosets were fabricated via UV curing in presence of a photo initiator, and their mechanical property and thermal behavior were investigated and compared. Different from the none HUB containing thermoset, the HUB containing thermosets (defined as PUT) could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical property. Furthermore, zinc oxide (ZnO) nanoparticles were modified with 3-(trimethoxysilyl) propyl methacrylate and the modified ZnO (defined as ZnO-TPM) was dispersed and polymerized into PUT matrix to prepare their nanocomposites. The influence of ZnO-TPM on the mechanical performance of the composites was evaluated, which indicated that the Young’s modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt% and then decreased. The composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT sample. In addition, the composite materials exhibited strong UV absorption capacity, implying their potential application in the circumstance where UV-shielding was required.

DOI: 10.1007/s10118-024-3121-9

Source: https://www.cjps.org/en/article/doi/10.1007/s10118-024-3121-9/