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), microfibrillated 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.