Studies on the Morphology, Cure Characteristics and Mechanical Properties of Acrylonitrile Butadiene Rubber with Hybrid Filler (Carbon Black / Silica) Composite

Carbon black (CB) and silica are the common reinforcing fillers that increase the usefulness of rubbers. In this work the effect of CB/silica hybrid fillers on the physico-mechanical properties of nitrile rubber was investigated. The total hybrid filler is kept constant at 50 phr (parts per hundred rubber) and silica content in the hybrid filler is varied as 0, 10, 20, 25, 30, 40 and 50 phr. Totally seven different combination of composite samples are prepared using two roll mill. Cure characteristics and physico-mechanical properties such as tensile strength, compressive strength, tear strength, elongation at break, 100%, 200% and 300% tensile modulus, abrasion resistance, hardness, compression set and rebound resilience are studied experimentally. Results showed that cure time t 90 , Scorch time ts 2 , minimumtorque (M L ), and maximum torque (M H ) of CB/Sil hybrid increased as silica content increased. The crosslink density of rubber hybrid composites has been determined from this stress strain curve using analytical method and ANSYS software. From the experimental results, it is found that all the properties studied except elongation at break, compression set, rebound resilience and abrasion resistance decreases with increase in silica content in hybrid filler as the silica content makes the composites less stiff.