Synthesis and characterization of novel polyester containing Schiff-base unit

Abstract

A new Schiff base type of polyester containing 2,2-dimethyl-1,3-diaminopropane was prepared by solution polycondensation of 1,4-benzenedicarbonyl dichloride with Bis(4-hydroxybenzilaldehid)-2,2-dimethyl-1,3-propildiimine (H₂HB₂P) which is derived from a 2,2-dimethyl-1,3-diaminopropane Schiff base reacted with a 4-hydroxybenzaldehyde monomer. The monomer and the polyester were characterized by FTIR,¹HNMR, and elemental analysis. The prepared polyester showed inherent viscosity of 0.29 dl/g in NMP at 25 °C, indicating their moderate molecular weight. The Polyester was completely soluble in aprotic polar solvents such asN -methylpyrolidone (NMP), dimethylformamide (DMF), Dimethyl Acetamid (DMAC), dimthylsulfoxide (DMSO). TGA determined the 10% weight loss temperature (T₁₀) at 280 °C and residual weight at 600 °C ca. 41% under nitrogen atmosphere.

Keywords:
polyester; Schiff base; 2; 2-dimethyl-1; 3-diaminopropane; thermal stability