Synthesis, Characterization, Optimization Reaction Conditions, and Molecular Weight Distribution of Poly(4-(4-nitrobenzylideneamino)

In this study, the conditions of oxidative polycondensation reaction of 4-(4-nitrobenzylideneamino)phenol (4-NBAP) were studied using oxidants such as air (O2), H2O2, and NaOCl in an aqueous alkaline medium of 50-90°C. Poly(4-(4-nitrobenzylideneamino)phenol) (P-4-NBAP) was characterized by 1H and 13C NMR, FTIR, UV-vis, size exclusion chromatography (SEC), and elemental analysis techniques. The solubility of oligomer was investigated by using organic solvents such as dimethylformamide, tetrahydrofurane, dimethylsulfoxide, methanol, ethanol, CHCl3, CCl4, toluene, acetonitrile, ethyl acetate. According to air (O2) oxidant (flow rate 8.5 L/h), the conversion of (4-NBAP) was 50.83% in optimum conditions such as [4-NBAP]o = [KOH]o = 0.05 mol/L at 60°C for 10 h. According to the SEC analysis, the number-average molecular weight (Mn), weight-average molecular weight (Mw) and polydispersity index (PDI) values of P-4-NBAP were found to be 11109, 12886 g mol-1 and 1.160 using air (O2); 17517, 23402 g mol-1 and 1.336 using NaOCl; and 8960, 10653 g mol-1 and 1.189 using H2O2, respectively. Also, thermogravimetric analysis showed poly(4-(4-nitrobenzylideneamino)phenol) is stable against thermal decomposition. The weight loss of P-4-NBAP was found to be 49.23% at 1000°C.