Effect of the epoxidized linseed oil concentration as natural plasticizer in vinyl plastisols

The use of natural-based additives as plasticizers for plasticized Polyvinyl Chloride (p-PVC) has been evaluated in this study. PVC traditional plasticizers based in phthalate have been substituted by epoxidized linseed oil (ELO). From the industrial point of view, this substitution presents an interesting alternative because ELO is a natural product, harmless, and biodegradable. The effects on the characteristics of plasticized PVC in the migration phenomenon have been analyzed. This analysis has been done from the point of view of optimizing the curing process parameters: the amount of plasticizer, temperature, and curing time. The use of these new plasticizers with low toxicity and low migration reduce significantly the toxic risks of the management of this kind of polymers. The curing process has been optimized through the study of the migration characteristics in accordance with the isothermal curing process from 140 to 220 A degrees C in curing periods ranging from 6 to 14 min. The obtained results present a weak tendency toward the migration of the plasticizer with a curing temperature of 220 A degrees C during 8 min. The determination of mechanical and micro-structural properties with Scanning Electron Microscope (SEM) techniques has allowed us to conclude that the optimal addition of ELO as plasticizer is in the range of 70-80 phr, under the optimal curing conditions.