Preliminary Studies on the Production of Nanofibrils of Cellulose from Never Dried

An ecologically friendly method, to obtain cellulose nanofibrils, starting from Never Dried Cotton (NDC) is described, where cotton bowls are opened and maintained in water. NDC cotton exhibits a highly accessible structure and porosity, thus allowing a more efficient enzyme action and chemical treatments and derivatization. In this work, the conditions utilized to synthesize nano-fibrils from NDC were also tested on once dried cotton; the latter failed to produce nano-fibrils when submitted to the experimental conditions applied. A first-drying of cotton fibers results in a structure characterized by a collapse of the NDC fiber structure, which change from a circular cross section to its typical “bean- like ” cross section, with reduced accessibility and porosity, and lower water sorption capacity. Those changes are of the same nature as the well known hornification described in pulp and paper science studies, associated with irreversible reduced accessibility, which affects paper properties, and in general, the utilization of cellulose for utilization as materials or fuel (i.e. alcohol). In this work, enzymatic hydrolysis of the fibers was followed the by high energy sonication for 20 to 50 minutes, resulting in the production of nanofibrils when using NDC