基于三嵌段聚合物/多酸静电复合自组装的水凝胶制备及功能化

In the previous NSFC Youth project (No.51003001), we successfully fabricated the block copolymer/Na9EuW10O36 hybrid core-shell micelles with the enhanced emissions via the electrostatic assembly. The physical hydrogels based on the triblock copolymer/Na9EuW10O36 with good self-healing behavior were obtained and dual switchable assembled hybrid materials were achieved. In this proposal, we propose to extend the research on functional hydrogels of cationic-neutral-cationic triblock copolymers/polyoxometalates. The effect of several parameters, the chemical structures of the block copolymers and polyoxometalates, the preparation condtions, etc. on the mechanical properties will be thoroughly investigated with the aim to preparing self-supported hydrogel materials. We plan to prepare the hydrogels of multiple lathanide-containing polyoxometalates, investigate the mechanism of emission enhancement and the structure-property relationship, and prepare the colorful hydrogels with tunable emission wavelength. Futhermore, we propose to construct the stimuli-responsive smart hydrogels based on the intriguing properties of block copolymer or polyoxometalates, i.e. pH, temperature, light, eletric sensitivities.

原青年基金项目(No.51003001)的研究进展包括成功构筑了嵌段聚合物/钨铕多酸的静电复合胶束体系，实现了多酸的荧光增强；制备了三嵌段聚合物/多酸静电复合的自修复荧光水凝胶；并构筑了光/电双重响应的杂化复合材料。已在Angew.Chem.Int.Ed.上发表论文1篇。本申请项目将延续嵌段聚合物/多酸静电复合制备水凝胶的研究，深入探索超分子结构与性能的关系，并实现其功能化。研究嵌段聚合物和多酸的化学结构、制备条件等复合水凝胶强度的影响，以实现制备较高力学强度的自修复性水凝胶。 利用此方法来制备多种含稀土发光金属的多酸的水凝胶，研究荧光增强的机理，考察水凝胶超分子结构对荧光的影响。进一步将多种发光多酸共自组装成水凝胶，制备可调控发光颜色的水凝胶。有效结合聚合物和多酸的优异性能，如聚合物的温度、pH敏感性，多酸的光电磁活性、氧化还原性等，构筑智能化的刺激响应体系。

本项目研究工作着力于发展聚合物/多酸有机无机杂化复合自组装凝胶的构筑方法，结构调控与功能化。首先以功能为导向，从构筑单元的结构设计出发，发展了以静电复合为主的三嵌段共聚物/多酸的超分子组装方法构筑了杂化凝胶，实现了凝胶荧光调控，及对热、气体、pH、光、电等外部刺激源的多重智能响应性；以天然手性聚多糖琼脂糖、卡拉胶等水凝胶为模板，利用多糖与多酸的氢键相互作用，在凝胶的受限微环境中有效诱导多酸产生基态手性（CD信号）和激发态手性（圆偏振发光），揭示手性诱导机理，通过改变温度、离子、溶剂等实现手性调控；利用小分子凝胶因子形成的手性超分子螺旋纳米带为模版，诱导产生手性多酸，进一步利用具有催化性能的多酸在凝胶中原位制备手性纳米粒子，通过控制凝胶化的降温速率实现对纳米粒子光学活性方向的调控；通过与嵌段聚合物复合，将多酸无机纳米粒子的静态光电性质拓展至智能响应动态功能，开发了其在气体检测器、温度传感器、自修复等领域中的应用。