基于多级取向结构的各向异性复合水凝胶的制备及力学性能研究

Hydrogels are ideal biomaterials owing to their “soft and wet” properties. However, traditional hydrogels usually have isotopic mechanical strength, which limits their further applications. In this project, we will develop some new methods and strategies to fabricate tissue-like nanocomposite hydrogels with hierarchical ordered structures and anisotropic mechanical strength. Through designing the synergetic interactions between the functional monomers and inorganic nanomaterials, the structure of the polymer networks and crosslinking degree can be tuned and the nanomaterials can be homogeneously dispersed within the networks. Large-scale and long-range ordered structures will be achieved by aligning the 0D, 1D and 2D nanomaterials under magnetic and electric fields. Furthermore, the nanocomposite hydrogels can be prepared by freezing the alignment structures using in-situ polymerization method. Relationship between polymer networks, alignment structures and mechanical strength will be systematically investigated. This applicant will provide new principles to design functional mechanical hydrogels.

高分子水凝胶“湿和软”的特性使其成为理想的生物医用材料。但传统的人造水凝胶只具备各向同性的力学性能，从而限制了其进一步应用。本项目拟在前期仿生纳米复合水凝胶研究的基础上，开发一些新的水凝胶合成方法, 制备像生物凝胶一样，具有微观结构多级取向并且宏观力学性能各向异性的复合水凝胶。设计功能高分子单体并通过其与纳米材料界面的协同作用，将纳米材料作为结构交联剂调控高分子网络的结构规整度及交联自由度，实现纳米材料在高分子网络中的均匀稳定分散；探索零维、一维、二维多元纳米材料混合体系在电场/磁场中的取向规律，获得大尺度三维长程有序的多级复杂结构；采用原位聚合反应形成交联的高分子网络对结构进行锁定，制备一系列具有多级取向结构的复合水凝胶，研究取向结构对水凝胶力学性能的各向异性增强。本项目通过探索高分子网络/纳米材料取向/宏观力学性能间的关联机制，为新型功能力学水凝胶材料的设计与制备提供思路。

高分子水凝胶“湿和软”的特性使其成为理想的生物医用材料。但传统的人造水凝胶只具备各向同性的力学性能,从而限制了其进一步应用。本项目重点关注复合水凝胶的微观结构和性能之间的关系，特别是多级取向结构，异质互穿内部结构，表面结构，以及多组分混合（油水，纳米复合）等所形成的各向异性复合凝胶。从结构出发，我们制备了具有优异的力学性能，热响应性机械性能、热刺激自恢复性能和形状记忆性能，液体输运等功能材料。阐述了功能背后的物理机理，详细介绍了制备方法。拓展了凝胶材料在生物医学、传感器以及柔性电子器件等领域的应用。