Novel, thermally stable and chiral poly(amide-imide)s derived from a new diamine containing pyridine ring and various amino acid-based diacids

Abstract

In this investigation, several novel optically active and potentially biodegradable poly(amide-imide)s were synthesized through direct polycondensation reaction. First, a new aromatic diamine compound including pyridine ring was synthesized, which was reacted with diimide dicarboxylic acids containing different natural amino acids such as l-alanine, l-leucine, l-isoleucine and l-methionine under green condition, using molten tetrabutylammonium bromide. These new chiral macromolecules were characterized using Fourier transform infrared spectroscopy, proton and carbon nuclear magnetic resonance, field emission scanning electron microscopy (FE-SEM), x-ray diffraction (XRD) and elemental and thermogravimetric analysis techniques. They show high solubility in polar organic solvents, such as N, N′-dimethylacetamide, N-methyl-2-pyrrolidone and dimethyl sulfoxide at room temperature. XRD and FE-SEM studies show that all the obtained polymers exhibit noncrystalline and nanostructure morphology. Due to the existence of amino acids in their structures, these polymers can show a potential biodegradability and biocompatibility behavior.