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Tris-(8-hydroxyquinoline)aluminum (Alq3), which is the most widely used material in organic electroluminescent devices, has been synthesized. Alq3 thin films have been deposited on glass and silicon substrates. The influence of light exposure on the optical properties of Alq3 thin films has been studied. It is confirmed that the photoluminescence (PL) of Alq3 thin film originates from its two geometrical isomers, namely, facial and meridional, which result from PL decay analysis (biexponential fit). It is also confirmed that the PL from both the isomers decreases for increasing light exposure time leading to the creation of luminescent quencher in Alq3 thin film.

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Four different samples of ferrocene-grafted hydroxyl-terminated polybutadiene (Fc-HTPB), containing 0.20, 0.52, 0.90, and 1.50 wt % iron, were synthesized by the Friedel-Crafts alkylation of ferrocene with hydroxyl-terminated polybutadiene (HTPB) in the presence of AlCl 3 as a (Lewis acid) catalyst. The effects of the reaction conditions on the extent of ferrocene substitution were investigated. The Fc-HTPBs were characterized by IR, ultraviolet-visible, 1 H-NMR, and 13 C-NMR spectra. The iron content and number of hydroxyl groups were estimated, and the properties, including thermal degradation, viscosity, and propellant burning rates (BRs), were also studied. The thermogravimetric data indicated two major weight loss stages around 395 and 500 C. These two weight losses were due to the depolymerization and decomposition of the cyclized product, respectively, with increasing temperature. The Fc-HTPB was cured with toluene diisocyanate and isophorone diisocyanate separately with butanediol-trimethylolpropane crosslinker to study their mechanical properties. Better mechanical properties were obtained for the gumstock of Fc-HTPB polyurethanes with higher NCO/OH ratios. The BRs of the ammonium perchlorate (AP)-based propellant compositions having these Fc-HTPBs (without dilution) as a binder were much higher (8.66 mm/s) than those achieved with the HTPB/ AP propellant (5.4 mm/s).