功能性纤维素基水凝胶材料及其应用研究进展

Research advances of functional cellulose-based hydrogels and its applications

水凝胶是一类经物理或化学交联形成具有独特三维网络结构的软物质材料,具有良好的生物相容性、优异的柔韧性、结构可设计性和功能可调性,在多功能材料领域备受关注。纤维素是自然界中含量最丰富的天然高分子材料,除了生物相容性好、可生物降解和可再生等优点,纤维素大分子链上的多羟基结构具有形成多重氢键作用的特点,易与水凝胶基体形成良好的分子亲和作用,产生相互叠加及协同作用。同时,纤维素的多羟基结构可为其改性提供活性位点,从而有效提高纤维素水凝胶的功能可调性,赋予水凝胶更多优异特性。在全球“碳达峰”和“碳中和”大背景下,纤维素是构建先进多功能水凝胶的理想绿色基元材料。通过创新设计的方法赋予纤维素水凝胶自愈合、自黏附、导电、抗冻、环境刺激响应等功能特性是当前天然高分子水凝胶领域的研究热点。笔者基于近年来功能性纤维素基水凝胶的研究前沿和动态,介绍了纤维素基水凝胶的构筑策略及其交联机制,梳理总结了纤维素在自愈合水凝胶、自黏附水凝胶、导电水凝胶、环境刺激响应性水凝胶和抗冻水凝胶等功能性凝胶材料领域的研究进展,重点阐述了功能性纤维素基水凝胶在柔性可穿戴设备、组织工程材料、生物医药载体以及伤口敷料等领域的构建及其应用研究进展。最后,总结归纳了功能性纤维素基水凝胶面临的问题与挑战,展望了纤维素基水凝胶材料未来可能的发展前景和研究方向,以期为设计和开发性能优异的纤维素基先进多功能材料提供参考。

As a type of soft materials with chemically and/or physically cross-linked three-dimensional networks,hydrogels have attracted great attention due to their good biocompatibility,excellent flexibility,structural designability,and functional tunability.Cellulose is the most abundant natural polymer on the earth,which would probably become the main chemical raw material resource in the future due to the global targets of carbon emission peak reduction and carbon neutrality.As a kind of natural polymer,cellulose has been used as an ideal green raw material for the fabrication of advanced multifunctional hydrogels due to its high affinity and adaptive synergy with hydrogel matrix.Apart from good biocompatibility,biodegradability and renewability,cellulose has the property of forming multiple hydrogen bonding with hydrophilic polymer chains due to their abundant hydroxyl groups on the macromolecular structure.Meanwhile,the abundant reactive hydroxyl groups on the cellulose chains make it liable to be modified to derive cellulose hydrogels with fascinating structures and properties.Therefore,the development of cellulose hydrogel with the property of self-healing,self-adhesion,electrical conductivity,anti-freezing,and environmentally responsive ability via innovative design methods has been a hot topic in the field of the biopolymer-based hydrogel manufacturing.In this review,the research frontiers and trends of functional cellulose hydrogel were summarized.The manufacturing strategy and crosslinking mechanism of cellulose hydrogels were introduced.Meanwhile,the research progress of cellulose in the field of functional hydrogels such as self-healing hydrogels,self-adhesive hydrogels,conductive hydrogels,environmental stimuli-responsive hydrogels,and antifreeze hydrogels were reviewed and summarized.Furthermore,the research progresses of manufacturing and applications of functional cellulose hydrogels in the field of flexible electronic devices,tissue engineering materials,biomedical carriers,and wound dressings were reported comprehensively.Finally,the problems and challenges of functional cellulose hydrogels were discussed,and the possible development trend and research direction of cellulose hydrogel materials in the future are prospected.It is expected that the summarization and review can help to provide theoretical reference for the design and development of cellulose-based advanced multifunctional materials with excellent performance.