Abstract

Various polyvinyl chloride (PVC) formulations were compounded with two types of plasticizers- diocthylphthalate (DOP) and epoxidized rubber seed oil (ERSO). The samples were subjected to beta irradiation at a rate of 2.4 mGy/h to total dose of 14.4mGy. The mechanical properties and the plasticizer permanence such as leaching and migration of plasticizers from the various samples were evaluated. The tensile strength and elongation at break were observed to increase with increase in concentration of the plasticizer up to 40 parts per hundred resins (phr). Absorbance values of sample films were recorded with UV spectrophotometer using the unplasticized film as standard. The irradiated samples were observed to have higher absorbance values than the nonirradiated samples. Both plasticizers were observed to be effective in stabilizing the radiolytic degradation of PVC. This study shows that the conventional plasticizer (DOP) can be replaced at low concentrations (up to 40 phr) without markedly compromising the plasticizer efficiency.

Key words: Polyvinyl chloride, plasticizer, epoxidized rubber seed oil, diocthylphthalate, beta irradiation.