Due to their excellent properties, thermosetting polymer materials have been widely used in many fields. Owing to the restriction of the crosslinked network, traditional thermosetting polymer materials exhibit insolubility and immiscibility. Therefore, the reprocessing of thermosetting polymer materials is a great challenge. With the depletion of petroleum-based resources, the utilization of natural resources for the preparation of bio-based thermosetting polymer materials is a major trend. In this study, eugenol-based covalent adaptable thermosets were prepared via UV curing and thermal curing according to thiol click chemistry. The mechanical properties of the eugenol-based covalent adaptable thermosets, which are better than those of the control sample, can be regulated according to the components. The eugenol-based covalent adaptable thermosets exhibited excellent transparency and UV shielding properties. The introduction of a dynamic covalent boronic ester (BSH) promoted the formation of residual char and enhanced the fire safety of the eugenol-based covalent adaptable thermosets. Owing to the dynamic borate ester bonds in the cross-linked network, the eugenol-based covalent adaptable thermosets exhibited significant stress relaxation behavior, and excellent shape memory function and self-healing properties. The samples were reprocessed at 100 °C several times. After three cycles of pulverizing and hot pressing, the recovery ratio of tensile strength of the reprocessed samples remained above 85%. This study provides a novel strategy for preparing self-healable, reprocessable and anti-flammable covalent adaptable thermosets with tunable mechanical properties.

中文翻译：

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基于动态共价硼酯和巯基-烯点击化学的丁香酚衍生的共价适应性热固性材料


由于其优异的性能，热固性聚合物材料已广泛应用于许多领域。由于交联网络的限制，传统的热固性聚合物材料表现出不溶性和不混溶性。因此，热固性聚合物材料的后处理是一个巨大的挑战。随着石油基资源的枯竭，利用自然资源制备生物基热固性聚合物材料是一个大趋势。在这项研究中，根据巯基点击化学通过紫外光固化和热固化制备了丁香酚基共价适应性热固性材料。基于丁香酚的共价适应性热固性塑料的机械性能优于对照样品，可以根据组分进行调节。基于丁香酚的共价适应性热固性塑料表现出优异的透明度和紫外线屏蔽性能。动态共价硼酯 （BSH） 的引入促进了残余炭的形成，并增强了丁香酚基共价可适应热固性材料的防火安全性。由于交联网络中的动态硼酸酯键，基于丁香酚的共价适应性热固性材料表现出显着的应力松弛行为，以及优异的形状记忆功能和自愈性能。样品在 100 °C 下再处理数次。经过 3 次粉碎和热压循环后，后处理样品的拉伸强度回收率保持在 85% 以上。本研究为制备具有可调机械性能的自修复、可再加工和抗易燃共价适应性热固性材料提供了一种新策略。