Migration from plasticized poly(vinyl chloride) into fatty media: importance of simulant selectivity for the choice of volatile fatty simulants.

An investigation was carried out to determine whether isooctane and ethanol behave like sunflower oil as fatty simulants for overall and for specific migration from PVC containing aromatic plasticizers (bis-2-ethylhexyl phthalate and tris-2-ethylhexyl trimellitate). In these films, the partition coefficients of migrants between simulant and polymer play a major role. The affinities of isooctane and of sunflower oil to all migrants were similar and isooctane can be considered as an alternative fatty simulant for plastized PVC. In contrast ethanol displays a different selectivity, and is not an adequate fatty simulant. Guidelines for the selection of solvents to be used as fatty simulants for migration testing are discussed. The scope of spectroscopic methods (FTIR and 1H-NMR) to monitor migration of aromatic plasticizers is presented.