Interfacial effects on the dielectric properties of elastomer/carbon-black/ceramic composites

A systematic series of ethylene-propylene-diene (EPDM) elastomer/carbon-black composites were studied to quantify the effect of additional ceramic fillers, especially of the interfacial contributions, on the dielectric properties of the composites. Substantial interfacial contributions to the composites' dielectric properties were present in all systems. For all composites studied-using ceramic fillers with varied dielectric nature and spanning orders of magnitude in dielectric constants-the interfacial contributions overwhelmed the ceramic filler k-values and dominated the dielectric performance of the composites. Non-trivial interplays between the carbon black and the ceramic fillers were also manifested, casting doubts on the validity of standard models used for the prediction of dielectric permittivities of such composites. Graphic abstract

Automated summary

The study examined a systematic series of EPDM elastomer/carbon-black composites with additional ceramic fillers to quantify their effects on dielectric properties, particularly the interfacial contributions. It was found that substantial interfacial contributions overwhelmed the ceramic fillers' dielectric constants and dominated the dielectric performance of the composites, challenging the validity of standard models for predicting dielectric permittivities. Additionally, non-trivial interactions between carbon black and ceramic fillers were observed, casting doubt on the accuracy of existing models.