Aromatic poly(amide-hydrazide)s: Synthesis and Characterization

Abstract

Aromatic poly(amide-hydrazide)s contain a higher percentage of polar group in the polymer backbone and represent a technologically important class of high performance material exhibiting high thermal, mechanical and chemical stability. The present investigation deals with the synthesis of various new poly(amide-hydrazide)s and copolymers from new novel aromatic dicarboxylic acid i.e., 2,5-bis(4-carboxymethylene phenyl) 3,4-diphenyl thiophene (BCMPDT) and/or terephthalic acid with m-amino-and p- aminobenzhydrazide by Yamazaki's phosphorylation method. BCMPDT was characterized by spectroscopic techniques such as IR, NMR, and mass. Polymers were characterized by IR spectroscopy, solubility, inherent viscosity, thermal analysis (DSC, TGA), and X-ray diffraction studies. These poly(amide-hydrazide)s had inherent viscosities in the range of 0.18–0.96 dL/g in DMSO at 30°C and showed good solubility in aprotic polar solvents. The polymers could be cast into transparent films and showed Tmax in the range of 520–640°C. The structure property correlation for the series of poly(amide-hydrazide)s synthesized was studied in detail.