Synthesis and Characterization of Novel Photoactive ‎Poly(ether-amide)s Based on Highly Substituted ‎Phenanthrimidazole

A new aromatic diamine monomer containing ether linkage based on the phenanthrimidazole ring, ‎۱,۱´-(۴,۴´- oxy bis(۱,۴-phenylene))bis(۲-(۴-aminophenyl)-۱H-phenanthro[۹,۱۰-d]imidazole) was synthesized through four-‎components condensation of ۴,۴´-diamino diphenyl ether, ۴-nitrobenzaldehyde, phenanthrene-۹,۱۰-dione and ammonium ‎acetate in presence of acetic acid, followed by palladium-catalyzed hydrazine monohydrate reduction. This new monomer ‎was further confirmed by FT-IR, ۱H NMR, and ۱۳C NMR spectroscopy. A series of new aromatic polyamides containing ‎phenanthrimidazole ring in the main chain was prepared by direct polycondensation of the prepared diamine with four ‎commercially available aromatic and aliphatic diacids. These polymers are essentially amorphous and were soluble in polar ‎aprotic solvents such as DMF, NMP, DMAc, and DMSO. Inherent viscosities of polyamides were in the range ۰.۴۲–۰.۵۳ ‎dL/g indicating the formation of medium molecular weight polymers. Polyamides exhibited glass-transition temperature (Tg) in ‎the range ۲۶۰-۲۸۰ °C. The ۱۰% weight loss temperature in air atmosphere measured by TGA was in the range ۴۵۴-۵۲۶ °C ‎indicating their good thermal stabilities. The photophysical properties of diamine and polyamides were investigated by UV-Vsible and fluorescence spectroscopy.

کلیدواژه ها:

Polyamides ، Polycondensation ، Bis-phenanthrimidazole ، thermal stability