Mutual diffusion at polystyrene/poly(vinyl methyl ether) as measured by ATR-FTIR and rheometry.

Mutual diffusion at PS/PVME (polystyrene/polyvinyl methyl ether) interface both below and above the glass transition temperature, T-g, of polystyrene was probed by Attenuated total reflection (ATR) and rheometry techniques. T he results were analyzed with a simple three layer model and a combination of Fickian and Case-II diffusion models. The mutual diffusion coefficients obtained by the two techniques are compared and the importance of Case-II d iffusion is discussed.