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The oxidative polycondensation reaction conditions of 4-[(4-hydroxybenzylidene) amino] phenol (4-HBAP) were studied with H₂O₂, air oxygen and NaOCl in an aqueous alkaline medium between 50 and 90°C. The structures of the obtained monomer and polymer were confirmed by FT-IR, UV-Vis, ¹H- and ¹³C-NMR and elemental analysis. The characterization was made by TG-DTA, size exclusion chromatography (SEC) and solubility tests. At the optimum reaction conditions, the yield of poly[4-(4-hydroxybenzylidene amino) phenol] (P-4-HBAP) was found to be 48.3% (for H₂O₂ oxidant), 80.5% (for air O₂ oxidant) and 86.4% (for NaOCl oxidant). According to the SEC analysis, the number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of P-4-HBAP was found to be 8950, 10970 g mol^-1 and 1.225, respectively, using H₂O₂; and 11610, 15190 g mol^-1 and 1.308 respectively, using air O₂ and 7900, 9610 g mol^-1 and 1.216, respectively, using NaOCl. According to TG-DTA analyses, P-4-HBAP was more stable than 4-HBAP against thermal decomposition. The weight loss of P-4-HBAP was found to be 49.27% at 1000°C. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) values calculated from electrochemical measurement. Electrochemical energy gaps (E_g′) of 4-HBAP and P-4-HBAP were found to be -5.46, -5.28; -2.26, -2.67; 3.20 and 2.61 eV, respectively. According to UV-Vis measurements, optical band gap (E_g) of 4-HBAP and P-4-HBAP were found to be 3.34 and 3.01 eV, respectively. Also, antimicrobial activities of 4-HBAP and P-4-HBAP were examined against selected some bacteria. The electrical conductivity of the polymer was measured after doping with iodine.

The oxidative polycondensation reaction conditions of 2-[(2-hydroxyphenyliminomethylbenzylidene)amino-phenol] (2-HPIMBAP) has been accomplished by using air O₂ and NaOCl oxidants in an aqueous alkaline medium between 50–90°C. The optimum reaction conditions of the oxidative polycondensation and the main parameters of the process were established. At the optimum reaction conditions, yield of the products were found to be 67.72% and 61.49% for air O₂ and NaOCl oxidants respectively. The structures of the monomer and oligomer were confirmed by FT-IR, UV-Vis, ¹H-NMR and ¹³C-NMR and elemental analysis. Also, TGA-DTA, SEC techniques and solubility tests were applied for characterization. ¹H-NMR and ¹³C-NMR data show that the polymerization proceeded by the C-C and C-O-C coupling systems of ortho and para positions and oxyphenylene according to -OH group of 2-HPIMBAP. The number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of oligo[2-(2-hydroxyphenylimi-nomethylbenzylidene)aminophenol] (oligo(2-HPIMBAP)) were determined. Thermal analyses of oligomer-metal complexes were investigated in N₂ atmosphere between 15–1000°C. Electrical conductivities of oligo(2-HPIMBAP) and oligomer-metal complexes measured with four point technique. Electrical conductivity of the oligo(2-HPIMBAP) was measured, showing that the oligomer is a typical semiconductor. Optical band gaps (E_g) of 2-HPIMBAP, oligo(2-HPIMBAP) and oligomer-metal complex compounds were determined by UV-Vis measurements. The monomer and oligomer were screened for antibacterial activities.