Luo Junzhi, Wang Tao, Sim Celine, Li Yuanzhe
School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore.
School of Telecommunications, Zhejiang College, Tongji University, Shanghai 200092, China.
Polymers (Basel). 2022 Jul 9;14(14):2808. doi: 10.3390/polym14142808.
Self-healing polymers are categorized as smart materials that are capable of surface protection and prevention of structural failure. Polyurethane/polyurea, as one of the representative coatings, has also attracted attention for industrial applications. Compared with polyurethane, polyurea coating, with a similar formation process, provides higher tensile strength and requires shorter curing time. In this paper, extrinsic and intrinsic mechanisms are reviewed to address the efficiency of the self-healing process. Moreover, formulation optimization and strategic improvement to ensure self-healing within a shorter period of time with acceptable recovery of mechanical strength are also discussed. The choice and ratio of diisocyanates, as well as the choice of chain extender, are believed to have a crucial effect on the acceleration of the self-healing process and enhance self-healing efficiency during the preparation of polyurea coatings.
自修复聚合物被归类为能够进行表面保护和防止结构失效的智能材料。聚氨酯/聚脲作为代表性涂层之一，在工业应用中也受到了关注。与聚氨酯相比，聚脲涂层形成过程相似，但具有更高的拉伸强度且固化时间更短。本文综述了外在和内在机制，以探讨自修复过程的效率。此外，还讨论了配方优化和策略改进，以确保在较短时间内实现自修复，并使机械强度得到可接受的恢复。二异氰酸酯的选择和比例以及扩链剂的选择，被认为在聚脲涂层制备过程中对加速自修复过程和提高自修复效率具有关键作用。
