REAL-TIME MONITORING OF SWELLING AND DISSOLUTION OF POLY(METHYL METHACRYLATE) DISCS USING FLUORESCENCE PROBES

A new technique, based on steady state fluorescence measurements is in troduced for studying swelling and dissolution of polymer discs. These discs are formed by free radical polymerization of methyl methacrylat e (MMA). Pyrene (Py) was introduced as a fluorescence probe during pol ymerization. Swelling and dissolution of disc shape poly(methyl methac rylate) (PMMA) samples in chloroform-heptane mixtures were monitored i n real-time by the Py fluorescence intensity change. The effects of so lvent quality and agitation (stirring) on film dissolution were studie d. Sorption and desorption coefficients of solvent and Py molecules we re measured respectively during dissolution of films, and found to be between 10(-7) and 10(-6) cm(2) s(-1). (C) 1997 Elsevier Science Ltd.