Influence of epoxidized extender oil properties on rubber performances

The rubber compounds are obtained by blending natural or synthetic rubber, reinforcing fillers, rubber extender oil and other additives. Choosing the best components for rubber compounding are essential in rubber industry. The main function of rubber process oil (extender oil) is to reduce viscosity and improve mobility of the rubber chains and thus enable better processing and dispersion of the filler particles. Mineral oils, particularly aromatic ones, were widely used as extender oil in rubber industry, however, due to their influence on environment and the toxicity, there is a demand for their replacement in rubber compounds. One of the environmentally friendly extender oils with possible use in the compounding process as processing aids are epoxidized vegetable oils. In this study, influence of the epoxidizes soybean oil as extender oil on the properties of compound based on natural rubber was investigated. Characteristics of epoxidizes soybean oil as extender oil was experimentally measured or calculated. The experiments were performed on a laboratory internal batch mixer, at the constant temperature of 90°C and a rotor speed of 60 rpm. The hardness, tensile strength, elongation at break, modulus at 100 and 300% elongation, and rheological properties of rubber compounds were determined. Power consumption during rubber compounding mixing phase was calculated on the basis of experimentally measured voltage and amperage.