自愈合多糖离子液体凝胶的构筑及性能研究

Multifunctional ionogels have great potential for the development in many cutting-edge technology fields. The construction of novel ionogels with the self-healing property to eliminate safety hazards and prolong service life, is an urgent task to develop high-efficiency, environmentally friendly and smart soft materials. This project focuses on the dynamic covalent chemistry and the principles of self-assembly, and tries to construct the self-healing ionogels by using the modified polysaccharides. The mechanisms of molecular interactions synergistically driven by reversible dynamic covalent and non-covalent bonds will be studied, and the formation rules of different microstructures will be discussed. The self-healing property and the synergetic effect of various driving forces will be investigated in detail. Based on the transformation of microstructures during the self-healing process, we will reveal the self-healing mechanisms and efficiency of different ionogels. The rheological, conductive and tensile properties, as well as the thermal stability of ionogels will be characterized. The regular methods for the adjustment of ionogel performance will be summarized. The functions and applications of ionogels with excellent performance including the self-healing property, high mechanical strength, good conductivity and tensile strength will be investigated, and the application fields of self-healing ionogels will be further extended. The study of this project can provide a theoretical basis for the preparation of self-healing ionogels with versatility, and significantly promote the development of the soft material science.

多功能离子液体凝胶在众多尖端技术领域孕育着巨大的发展前景，构筑新型自愈合离子液体凝胶以消除安全隐患并延长使用寿命，是发展高效、环保和智能的软材料亟需突破的课题。项目从动态共价化学和自组装原理出发，构建以功能改性的多糖分子为构筑基元的自愈合离子液体凝胶材料；研究可逆动态共价键和非共价键协同驱动下分子在离子液体中的作用机制，探讨微观结构的形成规律；考察凝胶的自愈合性能，描绘愈合过程中不同驱动力的协同效应，结合愈合过程中的微观结构演变，揭示不同离子液体凝胶的愈合机制及愈合效率；表征凝胶的流变学、导电、拉伸及耐热性能，总结性能调控的规律；筛选出兼具自愈合、高强韧、高导电及强拉伸等优异性能的离子液体凝胶，对其功能和应用进行探索，拓展自愈合离子液体凝胶的应用领域。项目的实施将为功能化自愈合离子液体凝胶的构筑提供理论依据，推动软物质科学的发展。

发展新型自愈合离子液体凝胶使其在受到外界损伤后实现自我修复，可消除材料使用过程中的安全隐患并延长其使用寿命，也是拓展离子液体凝胶应用的重要前提。本项目基于可逆的动态共价键（主要是亚胺键）及非共价键的协同驱动作用，成功构建了以多糖分子为构筑基元的自愈合离子液体凝胶材料。主要开展了以下几方面的研究：（1）利用扫描电子显微镜及红外等手段表征了凝胶的微观结构，并推测了凝胶的形成机理及分子间的作用机制。（2）利用光学显微镜、红外、流变仪等测试手段系统研究了凝胶的自愈合过程及效果，确定了凝胶自愈合过程中不同作用力如动态亚胺键及非共价键包含氢键、疏溶剂及范德华力等的协同效应；考察了不同凝胶的自愈合机制及自愈合效率，丰富了离子液体凝胶自愈合性能的评价机制；解析了凝胶的自愈合性质对其他宏观性质如力学性质、粘弹机械性质等方面的影响。（3）利用DSC、TGA、流变仪及万能试验机等手段测试了凝胶的热力学性质（高低温的耐受范围、分解温度等）、流变学性质（机械强度、粘弹性质、触变性等）、力学性质（拉伸强度、抗压缩能力、抗疲劳性等）、自愈合、粘附性以及光学性质等，实现了凝胶各类性质的有效调控，总结了基元分子结构对凝胶性质的影响规律。（4）最后，筛选了性质优异的自愈合凝胶材料，探索了凝胶在信息加密、染料吸附以及抗菌等方面的应用效果。综上，该项目实现了预期目标，进一步拓展了离子液体凝胶的应用。