PERMEATION OF BINARY-LIQUID MIXTURES THROUGH ELASTOMERS

Permeation of binary liquid mixtures through two commercially available elastomers were examined. The four systems studied are benzene-cyclohexane/neoprene, toluene-n-hexane/neoprene, toluene-methanol/nitrile, and toluene-o-xylene/nitrile. Permeation rate-time curves for several mixture compositions were prepared for each system. In the first three systems, the difference in the plasticizing effect of the two liquids on the membrane was very large. The liquid with the smaller plasticizing effect showed a permeation enhancement and the liquid with the larger plasticizing effect experienced a permeation depression. Toluene-o-xylene/nitrile represented a system in which the two liquids plasticized the membrane at almost the same rate. This system showed a permeation depression for both liquids.