Mass transfer of toluene vapor through protective polymer gloves

A series of solvent vapor permeation tests are conducted to investigate the diffusion of toluene vapor through two types of common chemical-resistant polymer gloves. The measured concentration–time data are fitted using a two-parameter regression equation, and an empirical mass flux model derived from the fitted concentration–time curve is proposed to explain the mass transfer behavior of toluene vapor through polymer gloves. The mass transfer behavior of toluene vapor through the tested polymers is initially dominated by case-II diffusion for the solvent sorption followed by anomalous diffusion. The mass transfer coefficient of toluene vapor in the polymers and the breakthrough time are found to vary as a function of the inlet surface concentration. Analogous desorption experiments reveal that desorption initially occurs by Fickian diffusion, followed by an anomalous diffusion, and finally by case-II diffusion. Although the initial rate of desorption is considerably faster than that of sorption, a low rate of desorption continues for many hours after solvent saturation. An investigation of the mechanical properties of new and artificially aged polymer gloves through stress relaxation experiments revealed that aging can have a pronounced effect on the mechanical properties with an associated change in the solvent vapor mass transfer behavior.