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In this research, the effects of formulation and the amount of triallyl cyanorate (TAC) as coupling agent on peroxide vulcanization and mechanical properties of the participated silica filled EPDM elastomer are investigated. The results of curing process and measuring mechanical properties (hardness, modulus, tensile strength, elongation at break, abrasion, resilience) of compounds show that silica accounts for mechanical properties improvement and TAC decreases Mooney viscosity and scorch time and also increases optimum curing time; therefore, it prevents compound scorching. In addition, results show that TAC improved rubber-filler interaction and apparent crosslink density, which reflected on mechanical properties under study and SEM photographs.

From the results of this study it can be concluded that higher stearic acid concentration as a part of curing activator and high level of curative (i.e. sulfur and accelerator) causes higher crosslink density, tensile strength, modulus and hardness, and lower NBR to nylon-PET cord adhesion. Accelerator type also affects NBR/nylon-PET cord adhesion and using NOBS the highest coating adhesion is achieved. Using semi-efficient vulcanizing (i.e. accelerator/sulfur ratio around 1) is the most suitable way for achieving high NBR/nylon cord adhesion. And finally, independent from accelerator type, sulfur amount and efficiency of vulcanizing system, coating adhesion is a semi-linear function of crosslink density of nitrile rubber.

The effect of a poly(ether glycol) brake fluid on cured EPDM (ethylenepropylene- diene monomer) elastomer based on 5-ethylidene-2-norborene has been studied. Different amounts of dicumyl peroxide (DCP) curing agent were used and the effect of ageing in a brake fluid (at 100°C for 70 h) on technical properties of EPDM have been investigated. By increasing the amount of DCP, significant changes were not observed. Tensile strength and modulus increased but elongation at break and abrasion loss decreased due to oxidative degradation and crosslinking. Hardness was constant due to the replacement of plasticizer with brake oil.