Temperature dependence of fluorescence and phosphorescence from probe molecules in polymer substrates

✍ Scribed by K.J. Smit; R. Sakurovs; K.P. Ghiggino

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 372 KB
• Volume: 19
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(83)90101-5

✦ Synopsis

The effect of temperature on the fluorescence and phosphorescence from a series of indole and coumaric acid derivatives incorporated in poly(methyl methacrylate), poly(styrenel and poly{vinyl alcohol) substrates has been investigated in the range 90 300 K. Activation energies for the temperaturedependent non-radiative decay of the triplet excited states showed abrupt changes at temperatures corresponding to the onset of local relaxation processes in the polymers. The values of activation energies and transition temperatures in any one polymer did not depend greatly on the probe, suggesting that the temperature-dependent triplet state deactivation mechanisms are mainly influenced by extrinsic polymer properties. However, the effect of temperature on the fluorescence intensity was found to depend markedly on the probe and state of ionization of any one probe. Possible explanations for these obserw~tions are presented.