Synthesis, characterization and photophysical properties of organosoluble and thermally stable polyamides containing pendent N-carbazole group

A series of novel polyamides that carry carbazole-containing pendent was prepared by direct polycondensation of a diamine, N-(4-(carbazol-9-yl)phenyl)-3,5-diaminobenzamidamide (DAC), and various aliphatic and aromatic dicarboxylic acids. All the resulting polyamides were amorphous with inherent viscosities ranged from 0.51 to 0.65 dL/g and were readily soluble in many organic solvents which could be solution-cast into transparent and tough films. The glass transition temperatures (Tg) of these polymers were affected considerably by their chemical structure and ranged from 195 to 300 °C. They had useful levels of thermal stability associated with relatively high temperatures of 10% weight loss (T10) in the range of 385-480 °C in nitrogen atmosphere. These polymers exhibited strong UV-vis absorption maxima in solution and in solid state, and their photo- and chemi-luminescence properties were studied. photoluminescence (PL) efficiency of the polyamides were affected by their chemical structure (PL quantum yield up to 32%). The aliphatic polyamides emitted blue light (λe.max = 435-450 nm), while the aromatic polyamides emitted green light (λe.max = 485-492 nm) both in solution and solid state.