基于动态共价键自愈合凝胶的构筑、性质及功能

As one kind of the most significant soft materials, gels have been widely applied in our daily life and industry production. Gels with self-healing or self-repairing properties can restore their functionalities and structures after damage, thus can extend the service life and improve the used safety of the materials, being the cutting-edge topics in gel materials. This project focuses on the fundamental rules of self-assembly and the concept of dynamic covalent chemistry, and try to obtain self-healing gels with fascinating and novel structures and desired functions mainly driven by dynamic covalent bonds, to study the self-healing performance, efficiency and mechanism. The mechanism of aggregates transition of the gels during the self-healing process will be studied in detail through spectra and AFM determination and theoretical simulation. This study is hopefully to open up a quantitative assessment system for evaluating self-healing performance, to reveal the driving role of dynamic covalent bonds in the gel formation and self-healing process, and to extend their functions and applications. Our long-term objective of this research is to provide theoretical guidance for the design and construction of self-healing gels, which will promote the development of constitutional dynamic chemistry (CDC).

凝胶作为一种重要的软物质材料，在日常生活和工业生产中应用广泛。具有自愈合性能的凝胶材料受到外界损伤后具有自修复能力和再生功能，能够延长材料的使用寿命，提高材料使用的安全性，是当前凝胶研究的前沿和热点。本项目从自组装的角度出发，立足于动态共价化学，设计合成一系列新颖结构的凝胶剂分子，在良溶剂（水、有机溶剂、离子液体）中以动态共价键驱动构筑具有特定功能的自愈合凝胶材料。通过凝胶微观结构表征、流变学性质和拉伸性能的测定，研究凝胶的自愈合性能，提出凝胶自修复性能的定量评价机制；利用波谱和AFM技术，结合理论模拟，探究凝胶愈合过程中微观结构的变化规律，揭示动态共价键在凝胶形成与修复过程中的驱动作用；考察不同类型凝胶的自修复效率，总结出共价键驱动凝胶愈合的演化机理，探索自愈合凝胶的功能和应用。项目的完成将为功能化自愈合凝胶的构建提供有力的实验数据和理论依据，推进动态建构化学的发展。

设计、合成了荧光基团、Se、氨基、醛基等修饰的功能化的凝胶剂分子，在适合的溶剂（水、有机溶剂、离子液体）中以动态共价键为主要驱动力，在氢键、静电相互作用、疏溶剂作用、范德华力等多重非共价键的协同作用下构筑了自愈合凝胶。通过凝胶微观结构、流变学性质和拉伸性能的测定，研究了凝胶的自愈合性能，发展了凝胶自修复性能的评价机制；利用红外、NMR和XRD检测手段，揭示了不用作用力在凝胶形成与修复过程中的驱动作用；考察了不同类型凝胶的自修复效率，总结出了共价键驱动凝胶愈合的演化机理，探索了自愈合凝胶再仿生纳米酶、工业废水净化和靶向药物缓释中的应用。