The University of Basrah discusses a doctoral thesis on )Synthesis and Characterization of Some New Polyamides, and Applications Study).

The College of Science in the Department of Chemistry discussed a doctoral thesis entitled: “Synthesis and Characterization of Some New Polyamides, and Applications Study”. Hold at the College of Science, Chemistry Department. A graduate student (Diyar Mohammad Ali Murad).     This research presents the design, synthesis, and comprehensive characterization of a new class of multifunctional polyamides that integrate ester, amide, and chalcone moieties within their molecular backbones. The study aims to develop advanced polymeric materials exhibiting high thermal stability, intrinsic fluorescence, and corrosion inhibition efficiency for potential applications in optoelectronic devices and protective coatings.

    The work commenced with the systematic synthesis of twelve novel monomeric intermediates (DA1–DA4, DB1–DB4, DC1–DC4) via esterification of multi-hydroxylated core structures (pentaerythritol, dipentaerythritol, and tripentaerythritol) with both aromatic and aliphatic diacids or diacid chlorides. These monomers were structurally confirmed through FTIR, ¹H- and ¹³C-NMR, and mass spectrometry. Subsequently, they were polymerized with a synthesized Bis-chalcone derivative via a condensation process in basic medium, yielding a series of twelve polyamides (PA1–PC4).

    The structural integrity and purity of the polymers were verified through FTIR and TLC techniques. Thermal behavior was investigated via thermogravimetric analysis (TGA), which revealed excellent stability with decomposition temperatures (Td) approaching 300 °C in many cases, particularly for polyamides derived from aromatic linkers. Morphological analysis using FESEM indicated that the polymers formed uniform, compact surfaces suitable for coating applications.

    The optical properties were examined by UV–Vis absorption and fluorescence spectroscopy in DMF. All polymers exhibited strong absorption in the UV region (200–450 nm), and notable emission bands ranging from 417 to 520 nm, with the emission intensity influenced by the nature of the backbone (aliphatic vs. aromatic). The results confirm the suitability of these polymers as fluorescent materials for sensing, labeling, or light-emitting applications.

    In addition to photophysical studies, a corrosion inhibition evaluation was carried out for selected polyamides (notably PB1 and PC1) using the weight loss method in 0.5 M HCl. The results showed inhibition efficiencies equal to 90%, attributed to the strong adsorption of the polyamide molecules on the mild steel surface via π-electron systems, lone pairs from nitrogen and oxygen atoms, and hydrophobic interactions from the aromatic units. These polymers functioned as mixed-type inhibitors, reducing both anodic and cathodic corrosion reactions.