| Abstrakt: |
Mechanism of electrical conductivity (σ), mechanical properties, and γ‐ray transmission properties of ethylene propylene diene monomer (EPDM)/butadiene rubber (BR) composites have been investigated from the viewpoint of free volume (ie, open hole size). The EPDM/BR composites (100/0, 70/30, 50/50, 30/70, and 0/100) loaded with 50 phr carbon black as a reinforcing filler and irradiated with different doses (10, 30, 50, 70, and 100 kGy). The ortho‐positronium lifetime (o‐Ps) for all the composites is measured using the positron annihilation lifetime (PAL) spectroscopy. Linear attenuation coefficients are measured for unirradiated composite at 59.5 keV using 241Am γ‐source. Scan electron microscope, electrical conductivity, stress‐strain, and hardness tests are investigated for all the composites before irradiation at room temperature (25°C). The results show a good linear correlation between the open hole size evaluated by PAL spectroscopy and all of the measured properties. These correlations confirmed the important role played by the free volume (ie, is governed by the open hole size) in all of the electrical conductivity, mechanical, and transmission properties in the composite. The results status that, the composite sample EPDM/BR (0/100) may be used as a radiation resistant material or as a radiation protector for tools in high‐level radiation areas. [ABSTRACT FROM AUTHOR] |
