Dynamic Mechanical Properties of EPDM Rubber Blends

The damping properties of ethylene-propylene-diene rubber (EPDM) with aliphatic hydrocarbon (C94) resin were investigated by dynamic mechanical analysis (DMA). It was found that the damping property of EPDM was improved after addition of aliphatic hydrocarbon resin. With increasing content of the resin, the main tan δ peak shifted to higher temperatures and the valid damping range in temperature was broadened. An addition of mica or NBR was found to widen the effective damping range. After addition of NBR into EPDM, the effective damping range of the blends was evidently extended in the applicable temperature region, especially when NBR content was 50 wt%. It was concluded that the NBR was incompatible with EPDM, and there existed two tan δ peaks in DMA spectra.