Mehta, B; Kathalewar, M; Sabnis, A
Polyvinyl chloride plastics (PVC), made flexible through the addition of di-2-ethylhexyl phthalate (DEHP) also known as di- octyl phthalate (DOP), are used in the production of a wide array of medical devices, toys, etc. During the past many years, concern has been voiced by public interest groups and regulatory agencies in Europe, Canada, and the United States regarding the potential adverse health effects of DOP migrating from children's toys during mouthing activities. Concern has focused on potential chronic effects on the kidney and liver. Therefore phthalate based plasticizers are facing ban in majority of the countries owing to its carcinogenic properties. Hence, the use of natural and/or biodegradable plasticizers, with low toxicity and good compatibility with several plastics, resins, rubber and elastomers in substitution of conventional plasticizers, such as phthalates and other synthetic conventional plasticizers attracted the market. Many modified vegetable oils are being used as partial replacement of DOP, but none of them has the historical record of acceptable performance comparable with phthalate plasticizers. In this study, cyclic carbonated soyabean oil(CSBO)was prepared by reacting epoxidised soyabean oil (ESBO) under pressure in presence of CO2. Reaction of ESBO to CSBO was confirmed by C-13-nuclear magnetic resonance (C-13- NMR) and Fourier transform infrared spectroscopy (FTIR). The CSBO was used as plasticizer in PVC in various proportions for replacement of DOP in samples as prepared from PVC-DOP-ESBO combination, keeping ESBO proportion constant in all samples. The incorporation of CSBO resulted in, increase in viscosity but reducing viscosity pick-up, improved tensile strength, exudation, and chemical resistance properties, with decreased elongation. The presence of CSBO Showed reduction in whiteness index due to brownish color of the product. Shore D harness was found to be increased with increase in CSBO content. The results of thermal analysis showed no significant variation in properties when compared to those of DOP-ESBO plasticized sheets which can contribute to the conclusion that CSBO can be used as a plasticizer in PVC with ESBO as a co-plasticizer to replace DOP.