DIFFUSION OF GOLD AND SILVER IN BISPHENOL TRIMETHYLCYCLOHEXANEN POLYCARBONATE

Diffusion coefficients between 5 x 10(-14) and 1 x 10(-16) cm(2) s(-1) have been measured for diffusion of gold and silver in the glassy sta te of bisphenol trimethylcyclohexanen polycarbonate in the temperature range between T-g = 507 K and 420 K using the radiotracer technique i n combination with ion-beam sputtering for serial sectioning. The Arrh enius plot exhibits a downward curvature, which is interpreted within an extension of the free-volume theory to the glassy state by Vrentas and Duda. The very small metal diffusivities in comparison to values f or gas molecules of comparable size suggest substantial interaction en ergies. (C) 1997 John Wiley & Sons, Inc.