Modeling of swelling by fluorescence technique in poly (methyl methacrylate) gels

✍ Scribed by Ö. Pekcan; Y. Yilmaz

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 210 KB
• Volume: 63
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19970328)63:13<1777::aid-app10>3.0.co;2-w

✦ Synopsis

A novel technique based on in-situ steady-state fluorescence (SSF) measurements is introduced for studying swelling processes in gels formed by free radical cross-linking copolymerization (FCC) of methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDM) in toluene. Gels were prepared at 75ЊC for various toluene contents with pyrene (Py) as a fluorescence probe. After drying these gels, swelling and desorption experiments were performed in toluene at 50ЊC by real-time monitoring of Py fluorescence intensity. A correction method was developed to obtain pure swelling curves, by using desorption curves of Py molecules. Li-Tanaka equation was employed to produce swelling parameters. Cooperative diffusion coefficients (D c ) were measured and found to be around 10 06 cm 2 /s for gels swollen in toluene.