Abstract:

In order to study the relationship between dye chemical structure and its properties, three naphthalimide-based fluorescent dyes were synthesized from 4-bromo-1, 8-naphthalic anhydride and different substituted o-phenylenediamine. The structures were characterized, and the UV-Vis diffuse reflectance spectra, UV-Vis absorption spectra and single-photon fluorescent spectra were investigated. The UV-Vis absorption spectra and single-photon fluorescent emission spectra wavelengths based on the optimized structures were obtained by the time-dependent density function theory. The calculated results well agree with the experimental data, where bathochromic shifts of absorption spectra happened and fluorescent intensity decreased with the electron-donating capability(-H < -CH3 < -OCH3) of the substituents. The fluorescence and fastness properties of dyed polyester fabrics using these three dyes are also determined, and dye b had the best dyeing property.

Key words: naphthalimide dyes, fluorescent dyes, time-dependent density function, dyeing, polyester fabric