Fast transient fluorescence technique (FTRT) for studying dissolution of polymer glasses

✍ Scribed by Ö. Pekcan; Ş. Uğur

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 195 KB
• Volume: 74
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19991024)74:4<948::aid-app21>3.0.co;2-d

✦ Synopsis

The fast transient fluorescence technique (FTRT) was used for studying the swelling and dissolution of a glassy polymer formed by free-radical polymerization of methyl methacrylate (MMA). Anthracene (An) was introduced during polymerization as a fluorescence probe to monitor swelling and dissolution. Swelling and dissolution processes of disc-shaped poly(methyl methacrylate) (PMMA) glasses in a chloroformheptane mixture were monitored by measuring the fluorescence lifetimes of An from its decay traces. A method is developed for low quenching efficiencies for measuring lifetimes, , of An, and it was observed that values decreased as the dissolution process proceeded. Desorption, D, and mutual diffusion, D m , coefficients of An molecules were measured during dissolution of PMMA and found to be around 5.4 ϫ 10 Ϫ6 (cm 2 /s) and 2.2 ϫ 10 Ϫ5 (cm 2 /s), respectively.