Facile preparation of spherical cellulose nanoparticles: chemical hydrolysis of fibres with tension

This paper describes a facile approach to prepare cellulose nanoparticles (CNPs) by chemical hydrolysis of cellulose fibres with tension, which eliminates the conventional requirement of high temperature and mechanical agitation/sonication. Furthermore, it gives the advantage of controlled spherical morphology. For this purpose, 60 psi load has been employed perpendicularly to the axis of fibres passing between rollers of different rotations per minute. This mechanism stretches the fibres to produce tension in them. Combing has also been employed to remove inherited immature and short fibres so that only the fibres with uniform tension can be utilized for chemical hydrolysis. The combing enhances uniformity and crystallinity index that were analysed by Uster Uniformity Test and X-ray Diffractogram respectively. Effect of tension was further investigated thermogravimetrically. Morphology of cellulose nanoparticles was studied by Atomic force microscopy that showed 8–16 nm amorphous spherical (CNPs) as the outcome of chemical hydrolysis of fibres with tension.