Effect of modified ZnO capped with N-trimellitylimido-L-alanine diacid as an optically active coupling agent on the morphology and thermal properties of poly (amide-imide)/ZnO nanocomposites

In this study, the poly(amide-imide) (PAI)/ZnO nanocomposites (NC) were prepared by means of ultrasonic irradiation. For this purpose, at first, surface of ZnO NPs was modified with N-trimellitylimido-L-alanine diacid as a new capping agent which has features such as nontoxicity, optical activity, and environmentally friendly. Then, the PAI was synthesized by the utilizing of tetra-n-butylammonium bromide and triphenyl phosphite as a condensing agent and green media. This method suggests simple, high-yield (>90%) polymerization reaction with green aspects using ionic liquid. Then, modified ZnO NPs were incorporated into the PAI matrix for the preparation of NCs. The obtained NCs were characterized by several techniques. Field emission scanning electron microscopy and transmission electron microscopy analyses of the NCs were accomplished to study the dispersion of fillers in the polymer matrix and demonstrated a rather good amount of dispersion. According to the thermogravimetric analysis results, the addition of ZnO NPs enhanced thermal stability of the obtained NCs.