Preparation and morphology distinguishing of novel ZnO ultrafine particle filled nanocomposites contain new poly(amide-imide) via ultrasonic process

In this paper, for the first time, a new nanostructure poly(amide-imide) (PAI) was synthesized from the polymerization reaction of 4,4΄-methylenebis(3-chloro-2,6-diethyl trimellitimidobenzene) as a novel diacid with 4,4΄-methylenebis(3-chloro-2,6-diethylaniline) using tetra-n-butylammonium bromide and triphenyl phosphite as a condensing agent and green media. This methodology offers enhancements for the synthesis of polymer with regard to yield of products, simplicity in operation, and green aspects by avoiding volatile solvents. The obtained polymer was used to prepare PAI/ZnO nanocomposites using nano-ZnO surface-coupled by 3-aminopropyltriethoxylsilane as a coupling agent through ultrasonic cavitations process. The formation of PAI was confirmed by ¹H-NMR, fourier transform IR spectroscopy (FT-IR), and elemental analysis. The obtained polymer was synthesized with good yield (90 %) and moderate inherent viscosity (0.48 dL/g). The resulting nanoparticle filled composites were also characterized by FT-IR, powder X-ray diffraction, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The TEM and FE-SEM results indicated a high dispersion level of the nanoscale inorganic particles in the polymer matrix. Results from the TGA thermographs indicate that the incorporation of KH550-functionalized ZnO nanoparticles into PAI matrix can impart significant improvements on the heat stability of the prepared nanoparticle-reinforced composites.