The effect of the curing time and temperature on final properties of flexible PVC with an epoxidized fatty acid ester as natural-based plasticizer

One of the most useful polymeric materials at industrial scale is plasticized polyvinyl chloride (P-PVC) or PVC plastisol. This is characterized by optimum balance among processing conditions, overall properties, cost, and versatility; however, it has some problems related to plasticizer migration (generally phthalates derivatives) with toxicity problems. As a consequence of the appearance of new regulations which restrict the use of phthalates, the study of new plasticizers with low toxicity and low migration has become a very interesting research field. In this study, the optimum curing conditions of vinyl plastisols with a natural-based epoxidized fatty acid ester as plasticizer have been investigated by the following mechanical properties: thermal behavior, color changes, solvent migration, and microstructure changes in terms of the curing conditions. This study was carried out with a plasticizer content of 70 phr (per hundred resin); different isothermal curing conditions ranging from 160 to 220 A degrees C, and curing times in the 6-10 min range were used. The results revealed that the best curing conditions are 200 and 220 A degrees C for curing times near to 14 and 10 min, respectively, which are similar to those used for other commonly used plasticizers.