Stress Relaxation and Thermal Analysis of Hybrid Biofiber Reinforced Rubber Biocomposites

Abstract

Natural rubber was reinforced using two hybrid biofibers namely sisal and oil palm. The stress relaxation characteristics of sisal/oil palm hybrid fiber reinforced natural rubber composites was analyzed with special reference to fiber loading and chemical modifications. It was seen that the rate of relaxation decreased with fiber content and was found to be maximum in gum compound. Chemical modification of the fiber surface was found to affect the degree of adhesion and thereby the nature of relaxation. The thermal stability of the composites was also investigated with reference to loading and chemical treatment. The kinetics of thermal degradation was also analyzed. Activation energy was calculated from two methods: the Horowitz and Metzger method and the Coats-Redfern method.