Application of dynamic rheological behavior in research on morphology and structure of ethylene-propylene-diene rubber/silicone rubber blends

Abstract

The blends of ethylene-propylene-diene rubber (EPDM) with silicone rubber (SR) and single-phase vulcanized silicone rubber (v-SR) were prepared using open rubber mixer, and the effects of composition ratio and interfacial crosslinking effect on the morphological structure of the blends were investigated by rheological behaviors, and the results of the morphological structure were verified using scanning electron microscopy and two-phase peel strength. The results showed that dynamic rheological behavior predicted successfully the morphological structure of high-viscosity polymer composite systems. When the amount of EPDM in the blend was 30-70 phr (mass, the same below), the morphological structure of the EPDM/SR blends exhibited two-phase continuous structure. Single-phase crosslin-king of SR in EPDM/SR blend with more than 1 phr of peroxide crosslinking agent in the amount of 70 phr of EPDM resulted in the fusion of the continuous structure of v-SR, which was transformed into a granular structure, and the phase domains of the granular structure increased with the increase in the amount of the crosslinking agent, whereas the high amount of the crosslinking agent resulted in the formation of a co-crosslinking of the two phases.

Keywords

• ethylene-propylene-diene rubbe，silicone rubber，blends， dynamic rheological beha-vior，morphological structure， interfacial crosslinking effect，interface compatibility，