The effects of three curing systems, peroxide, peroxide-phenolic combination and phenolic on selected properties of cured carbon black filled EPDM were investigated. The cured rubbers immersed in hot amine solution to evaluate their suitability for seal and gasket industry at elevated temperature and amine environments. These tests were essential for evaluating the durability of the gasket in a gas refinery. The FTIR spectrums revealed that the phenolic crosslink was constructed between rubber macromolecules during the curing process. The changing curing system from peroxide to peroxide-phenolic and phenolic increased the glass transition temperature of the filled cured rubbers between 3 to 5°C. There was not any significant difference between TGA thermographs of the selected cured rubbers with various cure systems and the residues ranged between 45 to 47%. Unlike of peroxide curing system, a dual phase was observed from SEM micrographs for peroxide-phenolic and phenolic cure systems. The phenolic cure system was not beneficial for rubber curing although, it reduced scorch time of the curing process. For the most studied mechanical properties, phenolic cure system deteriorated mechanical properties for both, aged and unaged cured rubbers. Increasing the amount of diene monomer in EPDM structure was beneficial for phenolic rubber cure system.

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