Processing characteristics and mechanical and electrical properties of chlorinated styrene–butadiene rubber/fly ash composites

Abstract

This work focused on the utilization of waste fly ash (FA) as filler in the reinforcement of chlorinated styrene–butadiene rubber (CSBR) with reference to their processing characteristics, morphological, thermal, and mechanical properties, solvent resistance, and electrical resistivity measurements. Rheometric properties such as optimum cure time and scorch time decreases with increase in filler content, whereas maximum torque increases up to 30 phr for FA particles. An appreciable increase in glass transition temperature has been observed from differential scanning calorimetric study. The mechanical properties such as tensile and tear strength, modulus, hardness, compression set, and heat buildup increases, whereas elongation at break and resilience decreases with loading of filler. The observed variation in mechanical properties has been supported by the fractography of the composites obtained by scanning electron microscopy. Variation in the bound rubber formation in CSBR/FA composite has been studied. The bound rubber content decreases with increasing extraction temperature, and its activation energy is also calculated from the Arrhenius plot. The electrical properties such as alternating current conductivity, dielectric constant, and dissipation factor are higher than that of CSBR, and the values increase with increase in the content of FA in the composites.