Chiang Mai Journal of Science

The wurtzite nanoparticles zinc oxide (n-ZnO) was prepared by using peroxide based route in this study. The effect of particle size of ZnO on cure characteristics and mechanical properties of natural rubber (NR) compounds were inquired. Two types of ZnO, commercial grade ZnO (c-ZnO) and n-ZnO, were used and compared. Masterbatches of ZnO particles were prepared by coagulation with formic acid of mixture between high ammonia latex with dry rubber and ZnO suspension. The dried masterbatches were mixed with vulcanizing ingredients on a two roll mill. The cure characteristic and tensile testing were determined. The n-ZnO filled compounds gave higher maximum torque and torque difference. The hardness of n-ZnO filled NR was higher. Moreover, the modulus at 300% elongation and tensile strength of n-ZnO filled compound were higher than that of c-ZnO filled rubber.