Abstract
The use of phosphorescence spectroscopy was used to reveal the mol. mobility of polyepoxide networks. The polyepoxides were prepd. by a photoinitiated cationic polymn. and crosslinking of (cyclo)aliph. bisepoxides. The emission properties were studied as a function of temp. Both phosphorescence intensity and triplet excited state half-life showed a discontinuity in their Arrhenius plots. For all networks this discontinuity was situated at .apprx.260 K and was due to the onset of quenching of the triplet excited state. The activation energy above the transition point was characteristic of the individual networks and was an indication of the increase in motion as the temp. was raised, ultimately leading to a simultaneous motion of large parts of the network. From these emission data the glass transition temp. and the width of the glass transition region were estd. The mech. properties of the network were established with dynamic mech. thermal anal. (DMTA) measurements. A striking correlation between mol. mobility (from emission data) and mech. properties (from DMTA) was obsd. [on SciFinder (R)]
Original language | English |
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Pages (from-to) | 332-338 |
Journal | Macromolecules |
Volume | 20 |
Issue number | 2 |
DOIs | |
Publication status | Published - 1987 |