Cure Characteristics of Foaming EVA Compounds: Influence of EVA Types and Cure Systems

Influence of poly(ethylene-co-vinyl acetate) (EVA) types and cure systems on cure characteristics of foaming EVA compounds were investigated. Three kind EVAs with different VA contents were employed. Influence of triallyl cyanurate (TAC) and dicumylperoxide (DCP) content on the cure characteristics were examined. The minimum torque ($T_{min}$) and delta torque (${\Delta}T$) decreased as the VA content increased. The ${\Delta}T$ was increased by adding TAC and by increasing the DCP content. For the foaming EVA compounds without TAC, the cure times such as the minimum cure time ($t_{min}$), scorch time ($t_2$), and optimal cure time ($t_{90}$) did not show a specific trend according to the DCP contents. For the foaming EVA compounds containing TAC, the cure times decreased as the DCP content increased. From the experimental results, it was found that efficienct DCP/TAC ratio for improvement of the crosslink density was 1.1~2.0.