STRUCTURAL INFLUENCES ON THE LIGHT-STABILITY OF 2-SUBSTITUTED AMINOANTHRAQUINONES AND HYDROXYANTHRAQUINONES IN MAN-MADE POLYMERS

The fluorescence and phosphorescence spectra and quantum yields of 2-amino-, 2-hydroxy- and 2-amino-3-hydroxyanthraquinones have been recorded in a variety of solvents and these data have been linked to studies on the light stabilities of the compounds in man-made polymers. Strong fluorescence is observed only from the 2-amino derivative and strong phosphorescence only from the 2-hydroxy derivative while the 2-amino-3-hydroxy derivative is non-luminescent. On flash photolysis in 2-propanol, the 2-amino and 2-hydroxy derivatives gave strong transient absorption due to the radical anion A-{radical dot} whereas the 2-amino-3-hydroxy derivative gave strong transient absorption due to the semiquinone radical AH·. These results are discussed in relation to the photostabilities of the compounds in polyester and nylon 6,6 film and fabric. © 1979.