Recent developments in penta-, hexa- and heptadentate Schiff base ligands and their metal complexes

Currently, a lot of research efforts have been directed toward exploiting the special high-performance characteristics of polymers with sulfur in the backbone. Sulfur-containing polymers fall under various classes and cover an extremely broad property range. The impetus to their development resulted from the unique properties and success in their applications, depending upon the type of linkage introduced. This review basically sets out to explain the design, synthesis, properties, and applications of various sulfur-containing polymers especially polyamides, polyimides, poly(amide-imide)s, polybenzimidazoles, polyurethanes, polyesters, etc. Outstanding performance of these polymers came up from their structures having sulfur-based groups such as thiophene, sulfide, sulfone, thiazol, and thiourea. Thus these linkages endow special features to such functional polymers. The sulfur-containing polymers are also described here with reference to their relevance as optically active, liquid crystalline, flame reta...

Recent Developments in Sulfur-Containing Polymers

Thermotropic liquid crystalline polyazomethines containing 1,3,4‐oxadiazole chromophors have been synthesized. These polymers are semiflexible liquid crystalline compounds containing luminescent mesogens. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), polarized optical microscopy (POM), and wide angle X‐ray diffraction (WAXD) have been used to evaluate their thermal and mesomorphic properties. The target polyazomethines present liquid crystalline behavior with classical calamitic textures, large mesophase range, and high thermal stability. The investigation of the optical properties of the synthesized polymers, in solution and solid state, confirmed a blue fluorescence.

Benjamin Joy Vasanthi

Papers

Synthesis and characterization of new poly(azomethine ester)s having phenylthiourea units