Synergic Effects of Molten Ionic Liquid and Microwave Irradiation in Preparation of Optically Active Nanostructured Poly(Amide-Imide)s Containing Amino Acid and Dopamine Moiety

A facile approach has been successfully developed for the preparation of a series of thermally stable and nanostructured chiral poly(amide-imide)s (PAI)s via the polycondensation reaction between 3,5-diamino-N-(3,4-dihydroxy-phenethyl)benzamide with four N-trimellitylimido-L-α-amino acids. An inexpensive and readily available molten salt, tetrabutylammonium bromide was used for the synthesis of polymers. The step-growth polymerization reactions produce a series of PAIs in high yields and inherent viscosity. The resulting PAIs were characterized by elemental analysis, viscosity measurements, thermal gravimetric analysis, solubility test, X-ray diffraction, Fourier transform infrared, and 1H NMR spectroscopy. The morphology evolution of polymer nanostructures is analyzed by field emission scanning electron microscopy.