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Elastomer business plays a significant role in the transportation industry. In fact, elastomers make the world move. Due to limited availability of natural rubber, synthetic elastomers bridge the gap between demand and supply in today's growing tyre and automobile industry. With more than ∼10000 KTA total world productions, the impact of synthetic elastomer business cannot be overlooked. The need of synthetic elastomers for tyre and automobile industries is stringently specific. Catalysis plays an inevitable role in achieving the growing demand of specific synthetic elastomers. The present study will describe how catalysis plays a significant role in the sustainable development of elastomers with special reference to polybutadiene rubber.

In the present study, epoxidized polybutadiene rubber (EBR) was synthesized from commercial-grade cispolybutadiene rubber (BR) and was characterized by NMR, FTIR, differential scanning calorimetry, thermogravimetric analysis and surface energy by contact angle measurement. To circumvent the drawback of the existing compatibilizers, the EBR was successfully used as an alternate compatibilizer for a silica-based 'green-tire' composite. The significant rise of surface energy was observed after epoxidation of BR, which represents the enhancement of the polar character of the rubber chains and eventually leads to improved compatibility between silica fillers and rubber chains. Out of various epoxidation levels, EBR with 30 mol% epoxidation showed the best compatibilizing effect. The optimum loading of EBR was found to be 12% with respect to total silica content. Apart from using EBR alone as a compatibilizer, combination of EBR with commercial silane-coupling agents, namely, bis(triethoxy-silylpropyl) tetrasulphide (TESPT) and 3-aminopropyltrimethoxy silane, was also investigated. The physico-mechanical and dynamic properties of the compounds with a combination of were comparable with those of the compound prepared using TESPT compatibilizer. The results observed with EBR-compatibilized samples revealed that EBR has a potential to be an effective compatibilizer which eventually could minimize the drawbacks associated while using commercial silane as a compatibilizer at the industrial scale.

This study focuses on the synthesis of zinc oxide (ZnO) nanoparticles by high temperature calcination as well as low-temperature hydrolysis methods and their efficiency as cure activator in styrene-butadiene rubber/ polybutadiene rubber blend. The synthesized nano-ZnO samples were characterized by means of X-ray diffraction, BET surface area and transmission electron microscopy. The synthesized nano-ZnO samples had wurtzite structure and average particle size in the 'nm' range. ZnO nanoparticles, synthesized on sepiolite template, were of smallest particle size (maximum number of particles in the range of 7-12 nm) and highest surface area (104 m 2 g-1). Polyethylene glycol (PEG)-6000 coated ZnO nanoparticles had rod-like structure; average diameter of the rods was 50 nm. In the case of PEG-coated ZnO containing compounds, optimum cure time of the blend was decreased by 5 min compared to that of standard rubber grade-ZnO containing compound (used as reference). Optimum cure time was lowered by 7-10 min in the case of synthesized nano-ZnO containing compounds compared to the reference ZnO based compound in presence of conventional filler, carbon black. It was also observed from ICP-OES analysis that the presence of very little amount of magnesium in one of the synthesized ZnO has noticeable impact on cure properties. PEG-coated ZnO increased the tensile strength of gum vulcanizates by 28% compared to the reference ZnO, acting as nanofiller at 3 phr loading. The study of curing behavior in dynamic condition was carried out using DSC. The results differ slightly from static curing except PEG modified nano-ZnO. Use of ZnO nanoparticles could provide faster crosslinking, better reinforcement at lower concentration compared to reference ZnO.

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