تهيه و بررسي خواص نانو كامپوزيت هاي نوين با كارايي بالا حاوي آمينو اسيدهاي مختلف بر پايه استفاده از نانو ذرات اكسيد روي و تيتانيوم دي اكسيد

چكيده انگليسي :

Synthesis and characterization of novel high performance nanocomposites containing different amino acids based on nano zinc oxide and nano titanium dioxide Mehdi Hatami M Hatami@ch iut ac ir Feb 2012 Department of Chemistry Isfahan University of Technology Isfahan 84156 83111 Iran Degree PhD Language FarsiSupervisor Prof Shadpour MallakpourE mail mallak@cc iut ac ir mallak777@yahoo com mallakpour84@alumni ufl edu Abstract Polymer based nanocomposites are classified as an important materials which were developed in recentyears The main goals of this project are the preparation of high performance nanocomposites based on metaloxide nanoparticles ZnO and TiO2 and optically active polymers Among the different polymers polyamides PA polyimides PI and poly amide imide s PAI show great interest due to the unexpectedchemical and physical properties These materials can be excellent candidates for using in nanocomposites asmatrixes The PAIs structures in this project were designed based on the diamines and diacid chlorides Thereaction of the mono amine containing compounds with 3 5 dinitrobenzoyl chloride caused to preparation ofdinitro benzamide compounds The catalytic reductions of nitro groups produced compounds 3 5 diamino N 4 hydroxyphenyl benzamide 1 and 3 5 diamino N 3 4 dihydroxyphenethyl benzamide 2 as diamines The formations of diamines were confirmed by NMR in dimethy sulfoxide The symmetric diacid chloridecompounds were synthesized in two steps In the first step condensation reaction of dianhydride and twomoles of different L amino acids including alanine phenylalanine leucine isoleucine and valine wereachieved and in the second step reaction of prepared imide acids with thionyl chlorides caused topreparation of diacid chloride compounds New aromatic aliphatic PAIs with benzamide pendant substitutedgroups have been synthesized in one step from the condensation reaction of equimolar amounts of thediamines and diacid chlorides in DMAc as a solvent in the presence of propylene oxide as an acid scavengerat low temperature All PAIs were obtained in high yields 78 and were characterized by commonspectroscopic methods such as FT IR 1H NMR and elemental analysis In other parts of the projectpolymer metal oxide nanocomposites have been prepared by introduction of nanoparticles NP s in polymermatrixed For this propose in order to increase the compatibility of nanomaterials with polymer matrixes thesurfaces of NPs were treated with silane coupling agents The ZnO NPs were modified with methacryloxypropyltrimethoxy silane KH570 and aminopropyltriethoxysilane KH550 Also TiO2 NPswere treated with KH550 Two polymeric structures based on phenyalanine BP and isoleucine BI aminoacid containing linkages were selected as matrixes Then PAI BP ZnO KH550 PAI BI ZnO KH550 PAI BP ZnO KH570 PAI BI ZnO KH570 for ZnO and PAI BP TiO2 KH550 nanocomposites NCs for TiO2were synthesized under ultrasonic process The resulting NCs were characterized by various techniquesincluding FT IR X ray diffraction XRD and their morphology were inspected by field emission scanningelectron microscopy FE SEM and transmission electron microscopy TEM The FE SEM and TEM resultsshowed that these particles have a mean diameter below than 85 nm and generally have fine edges FE SEMand TEM micrographs demonstrated uniform nanostructure inorganic moieties in polymeric matrix andconfirmed that the metal oxide NPs were presented in nanoscale in NCs structures The discovery of theatomic force microscope AFM has offered new chances for obtaining three dimensional high resolutionimages under ambient conditions to investigation of surfaces of materials like NCs structures It appeared thatwith introducing the metal oxide NPs in polymer matrix the hills of surface due to the residual of the NPs inthe surface were increased Keyword Optically active polymers Zinc oxide nanoparticles Titanium dioxide nanoparticles Surfacemodification High performance nanocomposites

حاتمي، مهدي

تهيه و بررسي خواص نانو كامپوزيت هاي نوين با كارايي بالا حاوي آمينو اسيدهاي مختلف بر پايه استفاده از نانو ذرات اكسيد روي و تيتانيوم دي اكسيد

پلي ﴿آميد-ايميد﴾ هاي فعال نوري و با كارايي بالا , نانو ذرات دي اكسيد تيتانيوم , معرف هاي اصلاح كننده سطح , خواص حرارتي