Morphological and property investigations of carboxylated cellulose nanofibers extracted from different biological species

Carboxylated cellulose nanofibers were extracted from different biological species, including cotton, spruce wood, bamboo and bacterial cellulose, through a combined (2,2,6,6-tetramethyl- piperidine-1-yl)oxyl (TEMPO)-mediated oxidation and mechanical defibrillation treatment. The cross-section dimensions of isolated cellulose nanofibers in suspension were characterized by small-angle X-ray scattering, where the results were in agreement with the transmission electron microscopy measurement. For the spruce wood samples, the effects of three experimental variables in the combined TEMPO-oxidation and mechanical treatment on the dimensions and degree of oxidation of the resulting cellulose nanofibers were quantitatively investigated.