Specific volume measurements and photoisomerization and fluorescence of probe molecules in glassy polymers, polystyrene and polymethylmethacrylate, are reported. A fractional free volume for physical aging, determined from the specific volume measurements, is found to be molecular weight dependent. The photochromic and photophysical measurements are sensitive to local free volume (microviscosity). The amount of local free volume necessary for photoisomerization of 1,1 prime -azonaphthalene is different in the two glassy polymers tested; this amount of local free volume is nearly independent of molecular weight except for low molecular weights (less than about 2000 MW for polystyrene).
|Original language||English (US)|
|Title of host publication||American Institute of Chemical Engineers, National Meeting|
|State||Published - Jan 1 1985|
ASJC Scopus subject areas