利用静电相互作用制备自修复聚合物材料

In this project, a series of cross-linked zwitterionic polymers will be prepared by solution radical polymerization of zwitterionic monomers which contains both positive and negative charges. These polymers will possess excellent self-healing properties based on electrostatic interaction, and the self-repairing process and mechanism will also be investigated. The specific objectives and contents are listed below: The electrostatic interaction can be adjusted by changing the molecular structure of zwitterionic monomers, the distance between positive and negative charges, and the type of anion and cation. The double network structure will be formed by covalent cross-linking and ionic electrostatic interaction between the clusters. Covalent cross-linking point of the polymer chain will endow the material strong mechanical properties, and the electrostatic interaction between the ion clusters provides the self-repairing property for the material. The distance between the positive and negative groups, the type of the cation and anion, the ratio between the monomer and cross-linker and the effect of the ionic strength on the self-healing property of the material will be well studied. The reversibility of the electrostatic interaction between the positive and negative charges will be verified and the self-repairing mechanism will be clarified, which will confirm that the electrostatic force is the main driving force of self-healing process. The biocompatibility and antimicrobial properties of zwitterionic polymer materials will be evaluated for their feasibility to be a promising long-term artificial skin.

本项目拟合成一系列同时含有正负电荷的可聚合两性离子单体，采用溶液自由基聚合方法制备交联两性离子聚合物，利用静电相互作用实现其自修复性能，研究其自修复过程及机理。具体目标和内容如下：通过改变两性离子单体结构，调节正负电荷之间的距离，阴阳离子的种类，实现静电力大小可调；利用共价交联和离子簇之间的静电相互作用实现高分子链结构双网络化，共价交联点赋予材料强机械性能，离子簇之间的静电作用赋予材料自修复性能；探讨正负离子官能团之间的距离、阴阳离子的种类、单体与交联剂的比例以及离子强度对材料自修复性能的影响，从分子水平表征正负电荷之间的静电作用具有可逆性，阐明其自修复机理，证实静电力是其实现自修复的主动力；表征两性聚合物材料的生物相容性和抗菌性，评价其作为持久性人工皮肤的可行性。

动态高分子材料在外界环境刺激作用下，动态键的断裂与重组可诱导高分子网络结构的动态调整，赋予高分子材料自修复、可控释放与降解、可回收等特性，在柔性电子皮肤、3D/4D打印、药物传输和疾病诊断等方面展现出广阔的应用前景。本项目利用可逆超分子相互作用及动态共价键发展了三类动态修复高分子及复合材料，对其动态可逆机制及性能进行了详细的研究。研究结果表明本项目研发的动态自修复高分子材料在可逆释放、人工皮肤、抗粘附涂层、3D打印等领域有着潜在的应用。.具体而言: 1) 利用两性离子之间的可逆静电相互作用制备了自修复两性离子聚合物防污涂层，并对其自修复及抗蛋白质粘附性能进行了详细研究。该涂层在经过微米和纳米尺度的损伤之后，浸泡于生理盐水中后，其表面湿度和生物防污性能可以得到完全的修复；2）通过羧基-钙离子之间的可逆离子相互作用、寡聚多巴胺分子之间的动态氢键和π-π共轭作用制备了聚合物包覆介孔二氧化硅复合纳米粒子，并研究了其在聚焦超声刺激下的可逆药物释放行为。结果表明这些体系具有较好的聚焦超声on-off可控释放效果，在按需药物输送领域具有潜在的应用价值; 3) 引入路易斯酸作为催化剂，实现常规脲键动态化，制备了系列具有自修复功能的聚脲材料，这些自修复聚脲材料在涂料、油漆以及3D打印等领域中具有显着的应用潜力。.本项目总计发表标注基金号论文13 篇，包括Advanced Functional Materials 和Journal of Materials Chemistry A 等，申请中国发明专利2项。