Synthesis and Characterization of New Organosoluble and Thermally Stable Aromatic Polyamides Containing Flexible Ether, Ketone, and Methylene Linkages

Abstract

A new aromatic diacid monomer, namely, 1,4‐phenylene‐bis‐[[4′‐(4″‐carboxy methylene) phenoxy phenyl] methanone] (PBCPPM) is successfully synthesized and characterized by physical constant, FT‐IR, NMR (1H and 13C) spectroscopy, and mass spectrometry. Synthesis of new series of polyamides with high thermal stability and improved solubility are performed by Yamazaki's direct phosphorylative polycondensation method from new PBCPPM with different aromatic diamines. The inherent viscosity of these polyamides is in the range 0.47–0.81 dL g−1. All these polyamides are amorphous or partly crystalline and reveal good solubility in polar aprotic solvents and exhibit glass transition temperatures between 201 and 232 °C. Initial decomposition temperatures are in the range 300–367 °C and T10 is in the range of 376–414 °C indicating good thermal stability of these polyamides. The present observations suggest that these polyamides can find potential applications as high performance polymers.

Synthesis and Characterization of Flexible Meta‐Aramid Modified with 4,4′‐Methylenedianiline

“…It showed that the solubility and main chain flexibility of the polymer were improved due to the introduction of MDA, but did not affect its thermal stability. Diwate et al [35] prepared new aromatic diacid monomers containing methylene, ether, and ketone bonds and obtained new aromatic polyamides by condensation with different diamines. The obtained polyamides showed excellent solubility in some polar non-protonic solvents and did not undergo thermal degradation below 300 °C, indicating that their thermal stability was not greatly affected.…”