Preparation and Characterization of Schiff Base Polythioamides Derived from [4,4'-Methylenebis (cinnamaldehyde)] by Willgerodt-Kindler Reaction

摘要

Five new polythioamides were prepared by polycondensation of a mixture of sulphur and various diamines with a dicarbonyl compound [4,4'-methylenebis(cinnamaldehyde)] (MBC). The used diamino compounds were ethylenediamine, 1,3-propylenediamine, meso-stilbenediamine, semicarbazide, and thiosemicarbazide. The polythioamides formed were characterized by elemental micro-analysis, FTIR, UV, Vis, and ~1H NMR spectroscopies, thermal analysis and viscosity measurement. All the polythioamides indicated a characterized band within 1230-1260 cm~(-1) due to vC=S vibrations. The synthesized polythioamides indicated better thermal stability up to 600℃. The dialdehyde (MBC) and polythioamides were soluble in number of organic solvents including tetrahydrofuran, dimethyl formamide, dimethyl acetamide, and dimethyl sulphoxide. The intrinsic viscosities of these polythioamide ranged within 0.393-0.5201 dL/g as compared to 0.174-0.249 dL/g for dialdehyde (MBC) in THF.