Dielectric relaxation and mechanical investigation of ethylene propylene diene monomer rubber with some crosslinking additives

Abstract

A systematic dielectric study over a frequency range from 100 Hz to 10 MHz was carried out on ethylene propylene diene monomer rubber (EPDM) mixed with zinc chloride and ammonium iodide with increasing quantities up to 16 and 8 phr, respectively. The measurements were carried out at a room temperature of Ϸ 25°C. Dielectric data were fitted in the frequency domain by using three Fröhlich terms discussing the different relaxation mechanisms in the system. These terms were interpreted according to the crosslinking that is formed by the addition of such materials to EPDM. The thermal aging for such systems was also studied and the data obtained are compared with those done before aging. The mechanical properties as well as the thermal gravimetric measurements were also studied and the data obtained are discussed.

Newsprint paper waste as a fiber reinforcement in rubber composites

“…Werkstatten GmbH, Germany) was used as a measuring cell. The cell was calibrated with standard materials,36 and the experimental errors in ϵ′ and ϵ″ were found to be ±3 and ±5%, respectively.…”

A novel cross-linked polyimide film: synthesis and dielectric properties

“…Furthermore, these curves keep their shapes but slide up at higher temperatures. These are in good agreements for thermoset and cross-linked polymers [24]. Dielectric constant of PI's, in general, are known to decrease gradually with increasing frequency [25].…”

Free-volume properties of epoxy composites and its relation to macrostructure properties

“…A guard ring capacitor type NFM/5T (Wiss Tech Werkstatten GMBH, Weilheim, Germany) was used as a measuring cell. The cell was calibrated using standard sample with known permittivity [21].…”

“…Furthermore, the results showed that: at 40 wt%, the fillers tend to act as a bridge to make molecular interconnected with epoxy matrix [21], resulting in small variation in the total free-volume hole size (V h ) and a decrease the total free-volume hole size (V h ) of epoxy and a decrease in its fraction (F). Consequently, fillers show a distinct improvement in the mechanical properties (tensile strength and hardness) especially in case of SiC.…”