Particle reinforced composites from acrylamide modified blend of styrene‐butadiene and natural rubber

Blends of styrene‐butadiene rubber and natural rubber that provide balanced properties were modified with acrylamide and reinforced with hydrophilic particles. The rubber composites show improved mechanical properties. Both modified rubber and composites showed a faster curing rate. The crosslinking density of the modified rubber composites increases with increasing amount of acrylamide in the modification. The glass transition temperature of the modified rubber composite shifts to a higher temperature compared with the unmodified rubber composite. The reinforcement factors show that the relative contributions of crosslinking effect and the filler–rubber interaction to the storage modulus vary with temperature. The modified rubber has improved tensile strength, elongation and moduli. The moduli of the modified composite increases and elongation decreases with increasing amount of acrylamide. Tensile fractural surfaces show good adhesion between filler and rubber matrix for all composites. The poly(acrylamide) grafts of the modified rubber increase stress relaxation rate. Stress relaxation also shows a stronger interaction within the modified rubber composites. POLYM. COMPOS., 40:758–765, 2019. Published 2018. This article is a U.S. Government work and is in the public domain in the USA