Effects of compounding ingredients of a tyre tread of NR based compound onphysical properties, special reference to hardness

The effect of dose of stearic acid, ZnO and process oil; type of carbon bla ck; dose of curatives like sulfur, and CBS, on hardness of a tyre tread of NR based compound has been investigated. Along with the hardness, other phy sical properties have also been measured with variation of the above compou nding ingredients. Empirical relationships for the hardness of the vulcaniz ates with the dose of stearic acid, ZnO and process oil, the particle size of carbon black, dose of sulfur and CBS have been established.