Optimization of the curing conditions of PVC plastisols based on the use of an epoxidized fatty acid ester plasticizer

The use of an epoxidized fatty acid ester (EFAE) as a natural-based plasticizer for plasticized PVC (P-PVC) has been evaluated in this work. The effect of the curing conditions has been studied by following several test techniques such as mechanical properties, thermal behavior, color changes, solvent migration and microstructure. Different curing processes at isothermal conditions (ranging from 160 °C to 220 °C) have been carried at curing times in the 6–16 min range. The optimum mechanical response (tensile strength values in the 9–10 MPa range and elongation at break close to 250%) is obtained for plastisols cured at 200 and 220 °C for 12 and 8 min curing times, respectively. These curing conditions also offer the lowest migration in n-hexane (lower than 11%) which is indicative of plasticizer total absorption. Furthermore, the use of these curing conditions does not lead to thermal degradation as confirmed by color measurements.