Performance evaluation of carbonized rubber seed shell (CRSS) filler as reinforcer in rubber binder

Abstract

The use of rubber-seed shell as a raw material for the production of carbonized filler was investigated. The produced carbonized rubber seed shells (CRSS) waste were characterized by its particle size, density and FTIR value. In this study, the effect of CRSS on the rheological and mechanical properties of rubber had shown great changes and nearly meet the properties of conventional used of filler which is carbon black. Five samples of rubber compounded with different loading of CRSS (0, 10, 15, 20 and 30 phr) were prepared. The higher filler loadings show increment in tensile strength, tensile modulus and hardness but decrease in elongation at break properties. At optimum CRSS loading (20 phr), the tensile strength and tensile modulus (M300) depict positive improvement. Meanwhile, the higher CRSS loading that have less developed structure also will worn the surfaces of rubber compound, thus result in decreasing abrasion resistance index (ARI) value as filler loading increase. This is due to higher CRSS loading will result in poor interaction between rubber matrix and filler content. Lastly, crosslinked density via Flory-Rehner equation depicts solvent uptake decrease linearly by adding more CRSS filler. Therefore, from the conclusive data and observations, the produced CRSS as alternative to current rubber black has great potential to be used as reinforcement filler in rubber compounding along with commercializing the waste materials to the next level.