Synthesis, characterization, thermal degradation and electrical conductivity of oligo[2-(2-hydroxyphenyliminomethylbenzylidene)aminophenol] and oligomer-metal complexes

The oxidative polycondensation reaction conditions of 2-[( 2- hydroxyphenyliminomethylbenzylidene) aminophenol] ( 2- HPIMBAP) has been accomplished by using air O-2 and NaOCl oxidants in an aqueous alkaline medium between 50-90 degrees 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 O-2 and NaOCl oxidants respectively. The structures of the monomer and oligomer were confirmed by FT-IR, UV-Vis, H-1-NMR and C-13-NMR and elemental analysis. Also, TGA-DTA, SEC techniques and solubility tests were applied for characterization. H-1-NMR and C-13-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- hydroxyphenyliminomethylbenzylidene) aminophenol] ( oligo( 2- HPIMBAP)) were determined. Thermal analyses of oligomer-metal complexes were investigated in N-2 atmosphere between 15-1000 degrees 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.