Photochromic and fluorescent probe molecules have been used to investigate local environments in glassy polymers. Information related to a distribution of local free volume has been obtained with photochromic probes in polystyrene, polymethylmethacrylate and polycarbonate, revealing that polymethylmethacrylate is a more mobile glassy matrix than polystyrene at room temperature. After physical aging, a narrowing of the size distribution is observed with the larger pockets of local free volume (or mobility) decreasing in number faster than smaller pockets. Effects of physical aging are most dramatic in the first couple of hours after quenching from the rubbery state. Fluorescence studies have shown that at a local scale physical aging can be related approximately to a function of log(time).
|Original language||English (US)|
|Number of pages||1|
|Journal||Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Materials Science and Engineering|
|State||Published - Jan 1 1990|
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Polymers and Plastics