The use of model substances for migration studies

Substances of differing volatility, polarity and molecular weight have been incorporated into plastics polymers and into cellulosic substrates and the migration of these model substances measured. These model substances act as surrogates for instrinsic migrants such as monomers, additives contaminants etc. and permit considerable data to be obtained on factors influencing migration from a limited range of experiments. Examples are illustrated by the use of model substances to study transfer from board packaging to microwave heated foods; to develop a method of test for microwave susceptors and to evaluate plastics polymers as barriers to migration.