Resumen
This work describes the synthesis of glycerol-derived polyurethane nanocomposite films containing unmodified cellulose nanowhiskers (CNW) or hexamethylene diisocyanate-modified cellulose nanowhiskers (HDICNW) as a mechanical support. Cellulose was prepared from sugarcane bagasse using a delignification and whitening approach that is wholly free of chlorine. CNW?s were obtained by acid hydrolysis in hydrochloric acid. The formation of nanocomposites was demonstrated by NMR, TEM, FTIR and WAXD. The films with different concentrations of CNW and HDICNW were characterized by FTIR spectroscopy, and stress-strain measurements. The samples experienced plastic deformation as subjected to an increasing elongation load, and right after yield limit, they fractured without necking. In such a case, the limit tension, which is the maximum stress supported by the sample, matches with the rupture tension. Polyurethane nanocomposites with CNW (CNW-PU) showed values of modulus of elasticity and tensile strength higher than HDICNW-PU.