基于离子交联作用构筑光控可重塑形状记忆离聚物及其响应机制研究

The utilization of dynamic cross-linked shape memory polymers to adjust their original shapes has been a frontier research topic in recent years. However, how to achieve the precise control of their original shapes has been still a challenge. The ionic cross-linking, which combines the characteristics of dynamic reversibility and near-infrared light responsiveness, is expected to construct novel multi-responsive reconfigurable shape memory polymers. It is worthy of deep study and practical application. This project aims to utilize free radical copolymerization and metal ionic cross-linking to develop a series of light-control reconfigurable shape memory ionomers. The precision of shape memory process and original shape can be controlled by utilizing the dynamic reversibility and photothermal conversion effect of ionic cross-linking. The influence mechanism of ionic groups, ionic concentration, ionic cluster morphology, composition and structure of ionomers on the photothermal conversion efficiency, shape memory properties and solid-state plasticity will be discussed. Then the effecting law and action mechanism of photothermal conversion effect, light-control shape memory effect and solid-state plasticity are revealed. The project also can provide theoretical and practical experience for the preparation and application of light-control reconfigurable shape memory polymers, and explore a new approach for the development of near-infrared light responsive materials.

利用动态交联作用调控形状记忆聚合物的原始形状是近年来科学界关注的研究热点和前沿领域，但如何简单高效地实现其形状的精准调控是一直以来的研究难题。离子交联作用作为一种简单易行的动态可逆交联作用并兼具一定的近红外光响应性，有望用于构筑新型多响应可重塑形状记忆材料，具有很大的研究价值和应用潜力。本项目拟采用自由基共聚法和金属离子交联作用构建一种光控可重塑形状记忆离聚物，利用离子交联体系的可逆性和光热转换效应实现对材料形状记忆过程和原始形状的精确调控，并系统考察离聚物的组成、单体结构、离子基团、离子浓度以及离子簇聚集形态等因素对材料光热转换效率、形状记忆性能和固态塑性的影响，探索离聚物光热转换效应的形成机制，进而揭示形状记忆离聚物的光响应形状记忆机理及重塑机制，为近红外光响应智能材料的制备提供新思路，也为光控可重塑形状记忆聚合物的设计与应用提供实践基础和理论依据。

针对实际应用对形状记忆聚合物可重构性、多响应性、多段形状记忆性能以及多功能应用的需求，我们通过结构设计与工艺调整制备了一系列多功能的形状记忆聚合物材料，主要取得了以下研究成果：1.利用微观形状记忆性能和固态塑性，实现了对形状记忆微球暂时形状和原始形状的调控；2.设计了一种具有光热双响应形状记忆性能和固态塑性的聚氨酯复合材料，并探索了其在光致驱动器、光控自修复防腐涂层以及光致焊接领域中的应用；3.通过原位生成法设计了一种具有光热双响应三段形状记忆性能的共聚物复合材料；4.设计了一种具有热、光和水三响应形状记忆性能的聚乙烯醇复合材料，并深入研究了材料的水响应机制和疲劳-修复机制；5.实现了光热双响应可逆多段形状记忆性能，并探索了其在光控开关和温度传感器中的应用；6.实现了在多响应形状记忆驱动器以及自供电传感器中的应用。通过本项目的研究，为新型多功能形状记忆材料的设计与制备提供了新策略，并为材料的机制研究和应用探索奠定了理论基础和数据支撑。