Synergistic effect of nano calcium carbonate (NCC)/carbon black (CB) on the cure characteristics and physico-mechanical properties of NR/SBR blends

Abstract

This research was carried out as to develop hybrid filler reinforced into the blend of natural rubber (NR) and styrene butadiene rubber (SBR). The NR/SBR blend was reinforced using carbon black (CB) and nano calcium carbonate (NCC). The NCC content varied from 2-10 phr which was incorporated into the NR/SBR blend filled with fixed 50 phr of CB. The main aim of this project was to study the synergistic effect of NCC and CB reinforced NR/SBR blends towards the curing characteristics using cure rheometer, the viscosity of uncured NR/SBR compounds, physical and mechanical property blends. From the results obtained, the optimum ratio of blending was identified at 4 phr of NCC loading. Tensile strength, elongation at break, modulus and hardness increased progressively with increasing the NCC loading from 0 phr up to a maximum value at 4 phr. This increment occurs due to consolidation of the network structure of the polymer chains with the increasing NCC content. Up to the optimum amount of NCC, the tendency for NCC particles to form aggregate was very high and hence reduces the properties of rubber blends. It proved that NCC acts as a co-reinforcing agent for CB to improve the performance in the NR/SBR blends.