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.

本研究以甲基丙烯酸异冰片酯为活性稀释剂，通过一锅法制备了一系列含受阻脲键（HUB）的聚氨酯-脲甲基丙烯酸酯预聚物和不含HUB的聚氨酯甲基丙烯酸酯预聚物。通过各种技术对预聚物进行了充分表征。然后，在光引发剂存在下通过紫外固化制备了它们的热固性材料，并研究和比较了它们的机械性能和热行为。与不含HUB的热固性材料不同，含HUB的热固性材料（定义为PUT）可以在相对温和的条件下通过热压进行回收再加工，机械性能恢复率较高。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)分散并聚合到PUT基质中以制备纳米复合材料。评估了ZnO-TPM对复合材料力学性能的影响，结果表明，当ZnO-TPM含量为1 wt%时，杨氏模量和拉伸强度逐渐增加至最大值，然后下降。与纯 PUT 样品相比，该复合材料还表现出良好的可再加工性和更高的回收率。此外，复合材料表现出很强的紫外线吸收能力，这意味着它们在需要屏蔽紫外线的环境中具有潜在的应用前景。