Compatibilization of SBR/NBR Blends Using Chemically Modified Styrene Butadiene Rubber

Abstract

Abstract The effect of dichlorocarbene modified styrene butadiene rubber (DCSBR) as a compatibilizer in blends of acrylonitrile butadiene rubber and styrene butadiene rubber (SBR/NBR) has been studied. The cure characteristics, physical properties, crosslink density, FTIR studies and low temperature transitions of the blends were determined as a function of chlorine content of DCSBR. Compatibilizing efficiency depended on the chlorine content of DCSBR and composition of blend constituents. Effective compatibilization was achieved when chlorine content of compatibilizer was 25% and SBR content of blend was either 50% or lower. FTIR studies, glass transition behavior measured by DSC and DMA showed that an appreciable extent of molecular level miscibility has been achieved in SBR/NBR blends by using DCSBR as a compatibilizer. Improvement in mechanical properties such as tensile strength, tear strength, resilience, hardness and compression set were achieved both when DCSBR was added and chlorine content of DCSBR increased up to 25%. The resistance of the vulcanizate towards air and oil aging improved with compatibilization. The change in technological properties correlated with crosslink density of the blends assessed from swelling studies and stress-strain data.