The oxidative polycondensation of 4-[( pyridin-3-ylimino) methyl] phenol (4-PIMP) with O(2), H(2)O(2), and NaOCl was studied in an aqueous alkaline medium between 50 degrees C and 90 degrees C. Oligo-4-[(pyridin-3- ylimino) methyl] phenol (O-4-PIMP) prepared was characterized by (1)H-NMR, (13)C-NMR, FT-IR, UV-VIS, size-exclusion chromatography, and elemental and thermal analyses techniques. At the optimum reaction conditions, the yield of O-4-PIMP was 18.9%, 39.4%, and 46.8% using H(2)O(2), O(2), and NaOCl oxidant, respectively. According to the TG analysis, the initial degradation temperature of O-4-PIMP was 218 degrees C, which was by 50 degrees C higher than that of 4- PIMP. Thermal analyses of 4-PIMP and O-4-PIMP were carried out in N(2) atmosphere at 15 - 1000 degrees C. The highest occupied molecular orbital, the lowest unoccupied molecular orbital, and electrochemical energy gaps of 4-PIMP and O-4-PIMP were determined from the onset potentials for n-doping and p-doping, respectively. Also, optical band gaps of 4-PIMP and O-4-PIMP were determined according to UV-VIS measurements.