Effect of Hollow Microspheres as Reinforcing Fillers on Natural Rubber Composites

This study aims to investigate the effect of a new hollow microsphere (RiM01) as a reinforcing filler for natural rubber (NR) instead of carbon black (CB) on rubber composites. The differences in vulcanization characteristics and mechanical properties of the natural rubber composites are being investigated by carbon black and hollow microsphere ratios. The results show that the addition of hollow microspheres decreases the tensile strength, abrasion resistance, and hardness of the rubber composites. However, when the hollow microspheres completely replace carbon black, the compression set is reduced from the initial 33% to 15%. In addition, the tensile and tear strengths of the rubber composites with 50 phr hollow microspheres are only reduced by 7.04% and 1.68% compared with those before aging; with 40 phr hollow microspheres, the 300% constant tensile stresses after aging are enhanced by 45% compared with those before aging. The aging resistance is improved.