Effects induced by gamma irradiation on free‐volumes, mechanical, and thermal properties of flame‐ and non flame‐retardant polyvinylchloride

Abstract

AbstractFlame‐retardant polyvinylchloride (FRPVC),typically used in cable insulation and jacketing construction for multi‐purpose reactor (MPR) at Atomic Energy Authority of Egypt, as well as carbon‐black FRPVC (CB‐FRPVC) and nonflame‐retardant PVC and CB‐PVC materials produced by Egyptian Electrical Cable Company (EECC), have been irradiated up to 160 KGy, at room temperature with a 60Co gamma source. Free‐volumes and thermal stability of irradiated and nonirradiated PVC samples have been examined using positron annihilation Lifetime Spectroscopy (PALS) and thermogravimetric analysis (TGA). In addition, the mechanical properties: tensile strength and elongation at break were examined. Considerable presence of flame‐retardant and carbon black additives in CB‐FRPVC sample led to both quenching and inhibition of Ps formation. The mechanical and thermal characterization showed that irradiation of PVC samples up to 80 KGy effectively induced cross‐linking to maxima. Higher doses then after results in degradation and thus a decrease in mechanical strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009