Abstract
Charge-transfer complex formed from the reaction of 2-(4-isobutoxyphenyl)-6-hydrazino-1,8-naphthalimide dye with chloranilic acid (CLA) has been studied in methanol at room temperature. The final reaction product has been isolated and characterized using UV-Vis. and infrared spectra. The thermal stability measurements (TG/DTG) as well as elemental analysis of carbon, hydrogen and nitrogen elements were also performed for this sample. The photometric titration curves for the reaction indicated that the data obtained refer to 1:2 (CLA:dye) charge transfer complex [(nap) 2(CLA)] was formed. The activation parameters. Delta E, Delta H, Delta S and. Delta G were obtained from the DTG diagrams by using Coats-Redfern method. The infrared spectra interpreted the mode of charge-transfer interaction associated with the hydrogen bonding exist between a two protons (-OH) of phenolic groups of CLA acidic central positions of acceptors and the terminal amino group for two dye moieties. Gamma irradiation was tested as a method for stabilization of fluorescent dyes doped in polymer sheets. The effect of gamma irradiation of 70 kGy dose on the properties of the charge transfer was studied using different techniques such as photolumencies (PL) and positron annihilation spectroscopy. The positron annihilation lifetime parameters and the doppler broadening line-shape S parameter were found to be dependent on the structure, electronic configuration the charge transfer complex. The positron annihilation spectroscopy can be used as a probe to study the stability of the fluorescent dyes.