Polymer Bulletin, Vol.60, No.1, 37-48, 2008
The oxidative polycondensation of 2-[(4-pyridilmethylene)-imino]phenol by molecular O-2 in alkaline medium: Synthesis and characterization
The polymer of 2-[(4-pyridilmethylene)-imino] phenol (2-PIP) has been formed from the oxidative polycondensation (OP) reaction by using molecular O-2 as the oxidant in an aqueous alkaline medium between 60-90 degrees C. The optimum reaction conditions and the main parameters of the process were determined. The yield of polymer was found as 50.1%. The structures of synthesized monomer and polymer were confirmed by FT-IR, UV-vis, H-1-C-13-NMR and elemental analysis. The characterization was made by TGA-DTA, size exclusion chromatography (SEC) and solubility tests. The H-1-C-13-NMR data shows that the polymerization proceeded with C-C and C-O-C coupling system of ortho and para positions and oxyphenylene according to -OH group of 2-PIP. The molecular weight distribution values of the product were determined from SEC measurement. The number-average molecular weight (M-n), weight-average molecular weight (M-w) and polydispersity index (PDI) values of poly-2-[(4-pyridilmethylene)-imino]phenol (poly-2-PIP) were found to be 11350, 12600 g.mol(-1) and 1.110, respectively. According to thermo gravimetric analysis (TGA), the carbon residues of 2-PIP and poly-2-PIP were found to be 18.17% and 45.10%, respectively, at 1000 degrees C.
Keywords:molecular oxygen;oxidative polycondensation;2-[(4-pyridilmethylene)-imino] phenol;polymer-Schiff base