On free volume of polymers above the glass transition

摘要

AbstractThe magnitude of the activation energy for diffusion,EDis shown to be inversely dependent on the fractional free volume of the polymer aboveTg. From the proportionality ofEDabove and belowTg, the magnitude ofEDbelowTgis also inversely dependent on the free volume in that temperature range. While this correlation holds very well for our determinations of fractional free volume aboveTgit does not correlate with the Simha‐Boyer fractional free volume belowTg, contrary to expectation