Improving the mechanical properties and curing characteristics of styrene‐butadiene rubber/butadiene rubber composites by incorporating silicon carbide

Abstract

Thermal conductive filler, silicon carbide (SiC), has been investigated for its effects on the mechanical properties, microstructural properties, physical properties, and kinetic characteristics of styrene‐butadiene‐rubber/butadiene rubber (SBR/BR). SBR/BR‐SiC's tensile strength, strain at break, and toughness were improved by 5 phr SiC content within the composite. Specifically, there was a 44% increase in tensile strength, a 51% increase in strain at break, and impressive 113% increase in toughness. Additionally, there was a notable reduction of approximately ~15% in the compression set. The calculated crosslink density using the Flory–Rehner equation proved that the SiC filler increased the covalent bonds between the polymer chains during the curing reaction. The rheometry results showed a reduction in the scorch and optimum curing times by ~10% via the incorporation of SiC. The addition of 5 phr SiC decreased the curing duration time by 47%. The scanning electron microscopy images taken from the samples at different magnifications showed that the particle agglomeration after SiC = 5 phr was the main factor in reducing the SiC performance in the composite.Highlights Tensile properties of SBR/BR were improved with high thermal conductive SiC. SiC accelerated the rate of vulcanization reaction of SBR/BR. The crosslink density was maximized with the addition of SiC to the compound. Better heat transfer by SiC led to a reduction in the energy consumption of curing. Thermal diffusivity was raised with the addition of SiC to the compound.