Modification of ZnO nanoparticles as an efficient activator for rubber vulcanization

Abstract

In the present work, ZnO nanoparticles (NPs) was modified with stearic acid (SA) to form ZnO‐SA and subsequently used as an activator for natural rubber vulcanization. Modified ZnO NPs were characterized by FTIR, X‐ray diffraction, SEM, and contact angle measurement. ZnO‐SA NPs were used in the vulcanization of natural rubber (NR) and compared with unmodified ZnO NPs. It was found that ZnO‐SA NPs decreased scorch time and activation energy of the vulcanization process compared to unmodified ZnO NPs. Mechanical performances of NR vulcanized with ZnO‐SA NPs and ZnO NPs were characterized by tensile properties, hardness shore A, compression set, permanent set, and rebound resilience. ZnO‐SA NPs not only increased the vulcanization process of NR but also improved the mechanical properties. This was interpreted as an increment in crosslinking density and better compatibility of ZnO‐SA NPs with NR.