Synthesis of glycidylethylhexylphthalate and its effects on poly(vinyl chloride) films as a novel plasticizer

To improve the processability and prevent the thermal degradation of poly(vinyl chloride) (PVC), various plasticizers and heat stabilizers have to be compounded. Phthalic plasticizers and metal soap stabilizers are usually used with epoxides as costabilizers. Epoxidized soybean oil (ESO), is one of the most commonly used epoxides because of its typical combined roles as a plasticizer and heat stabilizer in PVC compounds. ESO, however, sometimes causes surface contamination of PVC compounds because saturated fatty acids such as stearic and palmitic acids in soybean oil easily bleed onto the surface. In addition, some ingredients in ESO with hydroxide groups and unreacted double bonds during epoxidization also tend to increase the bleeding of ESO. This is due to their low compatibility with PVC resins. In this study, a novel plasticizer of PVC resins, glycidylethylhexylphthalate (GEHP), was synthesized, and its performance was evaluated. GEHP was designed to act as a plasticizer like normal phthalic plasticizers and to act as a heat stabilizer like ESO. Through the addition of epoxy groups in phthalic compounds, the resistance to bleeding was improved, and the plasticizing and heat-stabilizing effects on the PVC compounds were preserved. Soft PVC films were prepared with GEHP. The mechanical properties, thermal stability, and bleeding properties of the films were investigated. (c) 2005 Wiley Periodicals, Inc.