Functional Polymers. XXV. Fluorescence Spectra of Derivatives of Methyl Salicylate and Copolymers of Methyl Vinylsalicylates

Ultraviolet absorption and fluorescence spectra of methyl salicylate, isomers of methyl salicylate derivatives, and polymers with units of isomers of methyl salicylate have been investigated. The λ_max of methyl salicylate and its derivatives is centered around 310 nm. When the phenolic hydroxyl group is acetylated, the maximum is at 285 nm. Fluorescent emission maxima depend on the excitation wavelength. Two groups of maxima centered at 350 and 460 nm indicate that two molecular species (already present in the ground state) of the methyl salicylate moiety, probably tautomers, play essential parts as photoexcited states in the photophysics of methyl salicylate derivatives.