Effect of Micro- and Nano- Size of Cellulose Particles Extracted from Rice Husk on the Properties of Hydrogels

The effects of different size of cellulose particles extracted from rice husk on the properties of gelatin/cellulose hydrogels were studied. Micro size cellulose was extracted by alkali and bleaching treatments followed by acid hydrolysis to obtain cellulose nanocrystal (CNC). Both cellulose (micro) and CNC (nano) were used in hydrogels formulation with gelatin (in ratio 25% cellulose dispersion to 75% gelatin). Gelatin was then subjected to chemical cross-linking using glutaraldehyde as crosslinking agent with CNC entrapped in gelatin to produce hydrogels. SEM observation revealed that swollen micro cellulose has irregular and bigger pores compared to cellulose nanocrystal (CNC) hydrogel which has homogeneous and smaller pores arrangement thus affecting their swelling degree. The cellulose fibers exhibit enhanced thermal stability but contrary with the cellulose nanocrystals which showed lower thermal stability.