Fabrication of amino acid-based graphene-zinc oxide (ZnO) hybrid and its application for poly(ester–amide)/graphene-ZnO nanocomposite synthesis
Graphene/zinc oxide (ZnO) hybrid was prepared using biosafe l-phenylalanine-functionalized graphene. In this regard, ZnO nanoparticles (NPs) were modified by γ-aminopropyltriethoxyl silane (KH550) and were covalently attached to functionalized graphene sheets by reaction of amino groups on the outer wall of ZnO NPs with the carboxyl groups existing on graphene surface. Microscopic analysis of resulted hybrid revealed good dispersion of ZnO NPs on the graphene sheets. Afterward, the prepared hybrid was used as a filler for fabrication of polymer nanocomposite (NC). To this aim, a novel optically active poly(ester–amide) (PEA) containing different amino acids such as S-tyrosine and l-leucine was synthesized and structurally characterized using Fourier transform infrared and proton nuclear magnetic resonance spectroscopies, and CHN elemental analyses. Different percentages of NCs have been prepared through solution mixing method. Thermal stability of NC has been improved, which is be due to the increased interfacial interaction between the PEA matrix and functional groups on the hybrid.