Slow release from gels in various solvents: a fluorescence study

Abstract

Abstract A novel in situ steady state fluorescence experiment was performed for studying slow release processes in gels formed by free radical cross-linking copolymerization of methyl methacrylate and ethylene glycol dimethacrylate. Gels were prepared at 75 °C with pyrene (P y ) as a fluorescence probe. After drying these gels, slow release experiments were performed in various solvent with different molar-volume, V and solubility parameters, δ at room temperature by real-time monitoring of the P y fluorescence intensity. Slow release diffusion coefficients ( D ) were measured and found to be in between 0.23×10 −6 and 2.06×10 −6 cm 2 s −1 depending on the solvent used.