Preparation of spherical nanocellulose from waste paper by aqueous NaOH/thiourea

Sphere shape nanocellulose with cellulose II type crystal structure was prepared from waste paper by the swelling on aqueous system NaOH/thiourea/urea, a efficient, inexpensive, and less toxic strategy. The crystalline structure of bleached pulp and nanocellulose was performed using XRD. The nanocellulose exhibits the cellulose II type crystal structure. The crystallinity index of the nanocellulose is calculated to be 48.85%, lower than those of bleached pulp (64.42%). The FTIR of the bleached pulp and the nanocellulose were collected. It indicated that lignin and hemicellulose were removed during the dissolution of cellulose. Sphere shape nanocellulose particles were observed by scanning electron microscopy and transmission electron microscopy. The particle size distribution of nanocellulose was determined using dynamic light scattering. It showed an average size of 50 nm. The thermal behaviors of the bleached pulp and nanocellulose were studied by thermo gravimetric. The obtained nanocellulose had better thermal stability than bleached pulp, which have potential applications in transistors and batteries with high thermal stability.