基于胶束内分子聚集态变化导致力致变色的多功能智能水凝胶的研究

The mechanochromic smart hydrogel can provide an optical response to mechanical stimulation and has good biocompatibility, which has unique application value in stress sensor, material damage indicator and encryption device. It is one of the research hotspots in the field of gels. Conventional mechanochromic hydrogel materials have the problems of few types, single function, and poor adjustability of mechanical properties. Therefore, it is of great significance to develop a multifunctional mechanochromic hydrogel material with good mechanical properties. Some hydrophobic fluorescent chromophores can be incorporated into the hydrogel network by micelle copolymerization. The mechanochromic property of cyano-substituted oligo(p-phenylenevinylene) (cyano-OPV）derivatives or tetraphenylethylene (TPE) derivatives with aggregation-induced emission property are utilized in this project, which are introduced into micelles and copolymerized with acrylamide to prepare mechanochromic hydrogel with non-covalently crosslinked netwok. The aggregation state of the fluorescent molecules in the micellar will change under the external force to achieve mechanochromic response. The hydrogel has both high elasticity and self-healing properties. By optimizing the concentration and composition of micelles, the mechanical properties, mechanochromic properties and self-healing properties of the hydrogel materials were systematically studied, and then their applications in mechanical sensors and materials mechanical damage detection were explored. Moreover, it can provide guidance for designing and preparing more multifunctional smart hydrogel materials with good mechanical properties.

力致变色水凝胶能对力刺激做出直观的光学响应，并具有良好的生物相容性，在应力传感器、材料损坏指示器和加密装置等方面有着独特应用价值，是智能水凝胶领域的热点之一。传统的力致变色水凝胶种类少，功能单一，力学性能可调性差，因此开发一种力学性能良好的多功能力致变色水凝胶具有重要的意义。利用胶束共聚可以将一些疏水的荧光色团兼容到水凝胶网络中。本项目将具有力致荧光变色特性的氰基取代对苯乙烯寡聚物（cyano-OPV）或有聚集诱导发光性质的四苯基乙烯（TPE）衍生物引入到胶束中，与丙烯酰胺共聚制备一种胶束内非共价键交联的力致变色水凝胶。在力作用下胶束中的荧光分子聚集态发生变化从而实现力致变色，同时该水凝胶还具备高弹性和自修复性。通过优化共聚物和胶束的组成，研究该水凝胶的力致变色、自修复和力学性能，再探索其在力学传感和材料机械损伤检测等方面的效果，并最终为设计和制备更多力学性能好的多功能智能水凝胶提供基础。

力致变色水凝胶是一类智能凝胶材料。它能对力刺激做出直观的光学响应，并具有良好的生物相容性，在应力传感器、材料损坏指示器和加密装置等方面有着独特应用价值。传统的力致变色水凝胶种类少，功能单一，力学性能可调性差，因此开发一种力学性能良好的多功能力致变色水凝胶具有重要的意义。利用胶束共聚可以将疏水的荧光色团兼容到水凝胶网络中。将具有力致荧光变色特性的氰基取代对苯乙烯寡聚物（cyano-OPV）、有聚集诱导发光性质的四苯基乙烯（TPE）衍生物和芘衍生物引入到胶束中，与丙烯酰胺共聚制备一种胶束内非共价键交联的力致变色水凝胶。在力作用下胶束中的荧光分子聚集态发生变化从而实现力致变色。本研究成功制备一类力致荧光变化和可室温自修复的多功能智能凝胶材料。本项目利用简单的胶束共聚方法不仅可以将可调的力学性能、力致变色和自修复多功能集于一体，还可改变胶束内功能基元的种类，具有较强的可拓展性。同时该材料在力学传感和材料机械损伤检测等方面具有潜在的应用价值。