环境刺激响应型高强度智能水凝胶研究进展

摘要

Stimuli-responsive smart hydrogels with three-dimensional networks composed of cross-linked hydrophilic polymer chains can dramatically change their volume or other properties in response to various external stimuli,which are similar to bio-tissues. Due to such stimuli responsiveness,they show remarkable potential for numerous applications,such as artificial cartilages, artificial muscles and tissue engineering scaffolds,for which high mechanical properties are highly desired. Improving the mechanical properties of the stimuli-responsive smart hydrogels is one of the critical issues for their developments and applications. This review briefly introduces the design, fabrication and mechanism of stimuli-responsive smart hydrogels with high mechanical properties. Four types of smart hydrogels of ultra-low crosslinking hydrogels,nanocomposite hydrogels, topological hydrogels,and double network hydrogels,are introduced. Finally,the perspectives and challenges of stimuli-responsive smart hydrogels with high mechanical properties are discussed. The future work should focus on the trade-off effect of the stimuli-responsiveness and the mechanical properties of stimuli-responsive smart hydrogels,as well as their variations on environmental stimuli.%环境刺激响应型智能水凝胶能够对外界环境因素的变化产生显著的体积或其他特性的变化，且其性质和结构与生物组织类似，有望应用于人工软骨、人造肌肉、组织工程等领域，引起了广泛的关注。提高环境刺激响应型智能水凝胶的力学性能是智能水凝胶应用研究的重要方向之一。本文综述了近年来环境刺激响应型高强度智能水凝胶的研究进展，简述了高强度智能水凝胶的网络结构的构建策略与方法，分析了其具备高力学性能的机理，重点介绍了4类不同结构的高强度智能水凝胶，即超低交联结构水凝胶、纳米颗粒复合水凝胶、拓扑结构水凝胶以及双网络结构水凝胶，最后讨论了环境刺激响应型高强度智能水凝胶在面向应用的研究过程中仍然需要解决的关键科学问题，如智能水凝胶的环境刺激与力学性能的博弈效应以及响应环境刺激前后的力学性能差异等。