Transport of toluene/methyl ethyl ketone mixtures polyisobutylene

In this study, the diffusion behavior of methyl ethyl ketone (MEK)/toluene mixtures, with MEK molar fractions (x,) in the liquid source lower than 0.2, in polyisobutylene (PIB) was investigated with vapor-sorption Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy. FTIR-ATR Fickian diffusion models for both binary and ternary systems were used to determine diffusion coefficients. Obtained diffusion coefficients for MEK from the binary diffusion model did not agree with those determined previously for the diffusion of MEK/toluene mixtures, with x(1) > 0.2, in PIE. When the ternary diffusion model was used, the main-term and cross-term diffusion coefficients of MEK were comparable. (C) 2001 John Wiley & Sons, Inc.