TRANSPORT-PROPERTIES OF DICHLOROMETHANE IN GLASSY-POLYMERS .6. POLY(ETHYLENE-TEREPHTHALATE)

Sorption and diffusion of dichloromethane vapor in amorphous poly(ethy lene terephthalate) (PET) were investigated, with the aim of studying how aging phenomena, at different temperatures, influence the transpor t properties. It has been found that aging produces the appearance of non-Fickian behavior in the sorption curves as well as the reduction o f the diffusion coefficients. Furthermore, aging at 60 degrees C reduc es the sorption of vapor at low activity, and this led to the hypothes is of the presence of ordered domains in the aged samples. In this cas e, the process of solvent-induced crystallization is favored, and it a ppears at lower activity. (C) 1996 John Wiley & Sons, Inc.