基于纤维素纳米晶体的刺激响应功能材料的研究进展

Research progress in stimuli-responsive functional materials based on cellulose nanocrystals

纤维素纳米晶体(cellulose nanocrystal, CNC)具备高强度、高模量、结构可控、易于表面修饰、生物相容性、生物可降解性,在刺激响应功能材料的设计组装过程中扮演着越来越重要的角色。作为一类具有"智能"行为的大分子体系,刺激响应功能材料在受到外部环境的刺激时,能够做出灵敏响应,体现出设定的相应功能,CNC的引入不仅能够调控其力学性能,表面存在的羟基、羧基也为丰富材料的刺激响应源提供了便捷途径。本文从CNC的化学结构切入,介绍了CNC的特性及其构建的刺激响应功能材料的合成思路,并以刺激"开关"为主线,重点介绍了基于CNC的水、pH、热、光单一或多重刺激响应功能材料的研究进展,最后指出,提高纤维素纳米晶体表面修饰改性效率,拓宽多重刺激响应性,实现高性能的基于纤维素纳米晶体的多重刺激响应功能材料的制备是未来该领域的研究重点。

Cellulose nanocrystal (CNC) plays a more and more important role in the process of designing and assembly of functional materials,due to its high strength and modulus,controllable structure,feasible modification,biocompatibility and biodegradability.As a kind of macromolecule system with "intelligent" behavior,the stimuli-responsively functional materials make a sensitive response when stimulated by the external environment,and show the corresponding function.With the addition of CNCs,not only the mechanical properties of CNC-based functional materials are greatly improved,but also the hydroxyl and carboxyl groups on the surface of CNCs provide a convenient way to enrich the stimulus response source of these functional materials.Herein,combining with the chemical structure of CNC,the synthesis of CNC-based stimuli-responsive functional materials was comprehensively summarized.Meanwhile,the recent developments of single or multiple stimuli-responsive functional materials based on CNCs,such as water-,thermal-,pH-,light-responsive functional materials were summarized,with the stimulate switch taken as the main line.Finally,it was pointed out that future research would focus on improving the surface-modification efficiency of CNC,and broadening multi-stimulus responsiveness of CNC-based functional materials.The preparation of CNC-based functional materials with high performances will be significant in the future research as well.