Influence of hydrogenation and styrene content on the unaged and aged properties of styrene-butadiene copolymer

The influence of hydrogenation and styrene content on the properties of styrene butadiene copolymer (SBR) has been studied.There is an increase in glass transition temperature (Tg) associated with the reduction of double bonds by hydrogenation. The hydrogenated polymers demonstrate higher tensile strength, elongation at break and modulus values. The superior mechanical properties of HSBRs are due to the generation of polyethylene crystallites. The thermo-oxidative stability of saturated polymer is much higher than that of its unsaturated analogue. The samples with higher styrene content show higher modulus, but lower tensile strength and elongation at break, due to lower crystallinity. The thermo-oxidative stability of HSBR increases with increase in styrene content.