Characterization of cellulose nanofibrillation by micro grinding

A fundamental understanding of the morphological development of cellulose fibers during fibrillation using micro grinder is very essential to develop effective strategies for process improvement and to reduce energy consumption. We demonstrated some simple measures for characterizing cellulose fibers fibrillated at different fibrillation times through the grinder. The morphology and degree of fibrillation of the samples at different stages of fibrillation were characterized. The fibrillation and mechanical properties reached a maximum in 2 h, and did not show any significant change with further grinding. The lateral dimensions of the smallest nanofibrils were between 15 and 40 nm. A slight reduction in the crystallinity and degree of polymerization did not lead to decrease in mechanical properties of cellulose films. The lower tensile properties at the initial stages of fibrillation are mainly due to the presence of limited refined and heterogeneously treated fibers.