Synthesis, characterization and thermal degradation of oligo-2-[(4-hydroxyphenyl) imino methyl]-1-naphtol and oligomer-metal complexes

The oxidative polycondensation of 2-[(4-hydroxyphenyl) imino methyl]-1-naphtol (4-HPIMN) has been accomplished by using NaOCl, H2O2 and air O-2 oxidants in aqueous alkaline medium. Optimum reaction conditions of the oxidative polycondensation and the main parameters of the process were established. At optimum reaction conditions, yield of the products were found to be 77.0%, 91.6% and 99.0% for H2O2, air O-2 and NaOCl oxidants, respectively. The structures of the obtained monomer and oligomer were confirmed by FT-IR, UV-Vis, H-1- and C-13-NMR and elemental analysis. The characterization was made by TG-DTA, SEC and solubility tests. The H-1- and C-13-NMR data shows that the polymerization proceeded by the C - C coupling of ortho positions according to - OH group of 4-HPIMN. The molecular weight distribution values of the product were determined by using size exclusion chromatography ( SEC). The number-average molecular weight (M-n), weight-average molecular weight (M-w) and polydispersity index (PDI) values of O-4-HPIMN were found to be 1777, 2225 and 1.252; 1790, 2250 and 1.257; 4540, 5139 g mol 21, and 1.132 for NaOCl, H2O2 and air O-2 oxidants, respectively. According to TG analyses, the carbonaceous residue of 4-HPIMN and O-4-HPIMN was found to be 28.02% and 44.22% at 1000 degrees C, respectively. Thermal analyses of O-4-HPIMN-Cd, O-4-HPIMN-Co, O-4-HPIMN-Cu, O-4-HPIMN-Fe, O-4-HPIMN- Mg, O-4-HPIMN-Mn, O-4-HPIMN- Ni, O-4-HPIMN- Pb and O-4-HPIMN-Zn oligomer-metal complex compounds were investigated in N-2 atmosphere between 15 - 1000 degrees C.