The Surface and In-Depth Modification of Cellulose Fibers

This review updates the most relevant advances achieved in the field of surface and in-depth modification of cellulose fibers during the last 5 years. It reports work dealing with cellulose substrates on the nano-to micrometer scale, namely cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), micro-fibrillated cellulose (MFC), and bacterial cellulose (BC), as well as conventional lignocellulosic fibers. Several approaches have been applied for surface modification of these substrates, namely hydrophobization and oleophobization, physico-chemical adsorption, oxidation, cationization, esterification, urethane and siloxane formation, and grafting-from and grafting-onto macromolecular sequences. In-depth modification can be achieved by both partial esterification and partial oxypropylation.