Abstract
New heterocyclic azo-dyes derived from aniline derivatives using indolyl aldehyde as a coupler have been prepared and investigated by elemental analysis, IR, H-1-NMR and Uv-vis spectra furthermore, the spectral properties of the dyes, solvent effect and buffer solution pH effect have been studied for determination of pK(a) values (9.62-12.25) for all compounds. Kinetics of differential scanning calorimetry (DSC) of these compounds were measured. The activation energy and also critical temperature (T-c), glassy transition temperature (T-g) and melting point (T-m) temperatures were calculated.