In this investigation, a series of novel chiral and biodegradable polymer nanocomposites/zinc oxid (ZnO) based on amino acid were synthesized. For this purpose at first poly(amide-imide) (PAI) was prepared via solution polycondensation of N,N' -(pyromellitoyl)-bis-phenylalanine diacid chloride with 4,4?-diaminodiphenylsulfone.The optically active PAI was obtained with good yield and the structure of polymers was confirmed by different characterization methods such as fourier transform infrared spectroscopy )FT-IR(, 1 H-NMR and elemental analysis. The thermogravimetric analysis )TGA( termograms of the resulting polymer showed good thermal stability. In the second project, for compatibility with polymer matrix the hydrophilic ZnO nanoparticles were treated with coupling agent of ?-methacryloxypropyltrimethoxy silane (KH570) and ?-aminopropyltriethoxysilane (KH550). Then PAI/ZnO nanocomposites were synthesized under ultrasonic irradiation conditions. The resulting nanocomposites were characterized by various techniques including FT-IR, X-ray diffraction )XRD( and their morphology were investigated by scanning electron microscope (SEM), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The FE-SEM and TEM results indicated that the ZnO nanoparticles were dispersed homogenously in polymer matrix. The thermal properties of nanocomposites were studied by TGA. The TGA confirmed that the heat stability of the nanocomposites with increased nanoparticles content was improved. In the other project, Cloisite Na + was modified via cation exchange reaction using natural L-tyrosine amino acid. This novel chiral organomodified Cloisite Na + was characterized using FT-IR, XRD and TGA. Then the poly(vinyl alcohol) (PVA) nanocomposite was prepared by dispersing organomodified Cloisite Na + in PVA via ultrasonic irradiation. The results showed that a mixture of intercalated and exfoliated Cloisite Na + dispersion in PVA matrix. The TGA data was compared with the pure PVA and the results showed that the introduction of a small amount of Cloisite Na + /Tyr led to improvement in thermal stability of the obtained new nanocomposites. For the last project, nanocomposites of PVA/Cloisite Na + /ZnO with different of ZnO content were prepared. The resulting nanocomposites were characterized by various techniques including FT-IR, XRD and their morphology were investigated by SEM, FE-SEM and TEM. The FE-SEM and TEM results indicated that the nanoparticles were dispersed homogenously in polymer matrix. TGA confirmed that the heat stability of the nanocomposites was improved. Due to existence of amino acid in the backbone of obtained PAI, and ZnO in nanocomposites, it is predictable to be biodegradable.
