SYNTHESIS, CHARACTERIZATION, THERMAL DEGRADATION AND ELECTRICAL CONDUCTIVITY OF OLIGO[2-(THIEN-2-YL-METHYLENE)AMINOPHENOL] AND OLIGOMER-METAL COMPLEXES

The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O(2), H(2)O(2) and NaOCl oxidants in an aqueous alkaline medium between 20 degrees C and 90 degrees C. The structures of the monomer and oligomer were confirmed by FT-IR, UV-Vis, (1)H-NMR and (13)C-NMR and elemental analysis. TGA-DTA, size exclusion chromatography (SEC) techniques and solubility tests were applied for characterization. The (1)H-NMR and (13)C-NMR data show that the polymerization proceeded with C-C and C-O-C coupling system from ortho and para positions and oxyphenylene. The number-average molecular weight (Mn), weight-average molecular weight (M(w)) and polydispersity index (PDI) values of oligo[2-(thien-2-yl-methylene)aminophenol] (O-2-TMAP) were determined with SEC measurements. Thermal analyses of oligomer-metal complex compounds of O-2-TMAP with Cd(+2), Co(+2), Cu(+2), Zn(+2), Fe(+2), Zr(+4), Ni(+2) and Pb(+2) ions were investigated in N(2) atmosphere in the temperature range of 15-1000 degrees C. The highest occupied molecular orbital and the lowest unoccupied molecular orbital of monomer and oligomer were determined from the onset potentials for n-doping and p-doping, respectively. Optical band gaps (Eg) of 2-TMAP and O-2-TMAP and oligomer-metal complex compounds determined according to UV-Vis measurements. Also, electrical conductivities of O-2-TMAP and its metal complexes measured with four-point probe technique.