Spatial scale-dependent tracer diffusion in bulk polycarbonate studied by holographic relaxation

摘要

The diffusion of a photochromic dye tracer in polycarbonate was studied by a holographic relaxation technique(forced Rayleigh scattering)at temperatures close to the glass transition temperature.By varying the holographic grating period the results could be interpreted via the spatial scale dependence of apparent diffusion coefficients within a two-state diffusion model.This indicates inhomogeneities on the scale of a few micrometers in the polymer glass.