Polymeric positive-temperature-coefficient materials: dynamic curing effect

The object of this work was to prepare high-density polyethylene (HDPE)\ethylene– propylene–diene terpolymer (EPDM)\conductive carbon black (CB) composites by dynamic curing and to characterize the positive-temperature-coefficient (PTC) performances of the composites.EPDM and dicumyl peroxide were preblended in a research mill. The roll-milled strands were blended with HDPE and CB in a Haake mixer. The sheet resistivity and morphology of the HDPE\EPDM\CB composites with or without the dynamic curing process were investigated. It was concluded that the dynamically cured blends exhibit better PTC performance than the simple blends without dynamic curing. The effects of shear intensity and dicumyl peroxide content during the dynamic curing process were discussed for the PTC characteristics of the HDPE\EPDM\CB composites.