School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, P. R. China.
Department of Forest Biomaterials, College of Natural Resources, North Carolina State University, Campus Box 8005, Raleigh NC 27695-8005, USA.
Nanoscale Horiz. 2020 Mar 30;5(4):607-627. doi: 10.1039/d0nh00016g.
Different from traditional chemical surface modification, localized modification of the reducing end groups of cellulose nanocrystals (CNCs), i.e. the active aldehyde groups, provides new opportunities for diverse functional applications of this renewable nanomaterial without altering its surface chemistry and properties. Numerous reviews have deeply discussed the surface modification of the hydroxyl groups of CNCs, but no critical comment has been reported on the reducing end modification approach. This review is a comprehensive summary on the modification of the CNC reducing end, presenting the reaction mechanisms and conditions, discussing the different chemical modification strategies and characterization techniques, potential applications and future challenges in this field. In addition, the comparison between surface and end modification strategies of CNCs will highlight the potential of reducing end-functionalized CNCs to be used in various applications as an alternative to traditional surface-modified CNCs, or as additional functional nanoparticles for the design of advanced functional materials.
与传统的化学表面改性不同，纤维素纳米晶体（CNCs）还原端基团（即活性醛基）的局部改性为这种可再生纳米材料的多样化功能应用提供了新的机会，而不会改变其表面化学和性质。许多综述深入讨论了 CNCs 羟基的表面改性，但对于还原端改性方法，没有报道过关键评论。本综述全面总结了 CNC 还原端的改性，介绍了反应机制和条件，讨论了不同的化学改性策略和表征技术、该领域的潜在应用和未来挑战。此外，CNCs 表面和端基改性策略的比较将突出还原端功能化 CNCs 在各种应用中的潜力，可作为传统表面改性 CNCs 的替代物，或作为用于设计先进功能材料的附加功能纳米粒子。
