Modified nanocrystalline cellulose partially replaced carbon black to reinforce natural rubber composites

Abstract As a renewable nanomaterials, nanocellulose was generally considered as a green filler for reinforcing polymer. In this study, nanocrystalline cellulose (NCC) isolated from softwood pulp was successfully modified, and the modified nanocrystalline cellulose (m‐NCC) was used to partially replace carbon black (CB) to reinforce natural rubber (NR). Then, the dispersion of m‐NCC in the rubber matrix and the mechanical properties of NR composites were studied. The results showed that the surface modification of NCC improved its dispersion in the NR matrix and the filler‐rubber interfacial interaction. In addition, the m‐NCC partly replaced the CB‐reinforced NR composite with a lower stress at 300% elongation, but the tensile strength, elongation at break, tear strength, and wear resistance of the composites were significantly improved. Besides, the dynamic compression fatigue heat built‐up of the composites in which m‐NCC partially replaced CB was increased, but DIN abrasion and the flex cracking resistance was improved. From these properties, it can be seen that the partial replacement of CB by NCC could basically approach or even achieve the effect of NR composites reinforced by CB, indicating that the NCC had good rubber reinforcement ability.