Nanocellulose-triggered structural and property changes of acrylonitrile-butadiene rubber films

In this study, the effect of cellulose nanocrystals (CNCs) incorporation on the structure-properties of acrylonitrile-butadiene rubber (NBR films), with particular focus on curing enhancement and reinforcing potential, was investigated. The NBR crosslinking efficiency, observed from nuclear magnetic resonance analysis, increased with successive CNC concentration increases due to better dispersion of ZnO from Zn-cellulose complex formation. Energy dispersive X-ray and transmission electron microscope analysis of the films revealed increasingly well-dispersed ZnO with increasing CNC. The increase in the crosslinking density in conjuncture with the reinforcing capability of CNCs resulted in increases in the tensile strength, stiffness, toughness, tear strength and elongation by 203, 8300, 664, 179, and 14%, respectively for films containing 3 phr CNC compared to the neat NBR. The incorporation of 0.5 phr CNC reduced the water absorption of neat CNC by 250%. Overall, water absorption of the nanocomposite films was considerably lower than that of the neat NBR through CNC consolidation of the rubber particles by reducing free volume in the NBR structure. The nanocomposite films show promise for glove and other dipped product applications where improved tear resistance and overall physical properties improvement are needed without compromising the integrity.