Synthesis and characterization of new aromatic polyamides bearing crown ethers or their dipodal counterparts in the pendant structure. II. Benzo-15-crown-5 and ortho-bis[2-(2-ethoxyethoxy)ethoxy]benzene

• Published in: Journal of polymer science. Part A, Polymer chemistry Polymer chemistry, 2006-07, Vol.44 (13), p.4063-4075
• Main Authors: Calderón, Verónica, García, Félix, De la Peña, José L., Maya, Eva M., Lozano, Ángel E., de la Campa, José G., de Abajo, Javier, García, José Miguel
• Format: Article
• Language: English
• Subjects: Applied sciences; crown ethers; Exact sciences and technology; gelation; monomers; Organic polymers; Physicochemistry of polymers; podands; polyamides; Polycondensation; Preparation, kinetics, thermodynamics, mechanism and catalysts
• ISSN: 0887-624X; 1099-0518
• DOI: 10.1002/pola.21510

This article describes the synthesis and characterization of two diacid monomers, each containing a benzo‐15‐crown‐5 subunit or its dipodal counterpart. Both novel monomers were reacted with technical aromatic diamines with Yamazaki's direct polyamidation method to render modified polyisophthalamides with high molecular weights containing side moieties of cyclic and acyclic ethylene oxide sequences. All the polymers were soluble in aprotic polar solvents and showed high glass‐transition temperatures in the range of 190–345 °C. The polymers with side crown ethers showed much higher glass‐transition temperatures than those with acyclic linear side ethylene oxide arms. The chemical composition, particularly with respect to the diamine and the open or closed character of the pendent ethylene oxide sequence, also affected other general properties such as the mechanical resistance, mechanical modulus, or water absorption. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4063–4075, 2006 This work describes the synthesis and characterization of 10 new aromatic polyisophthalamides containing benzo‐15‐crown‐5 substructures and comparable acyclic oxyethylene dipodal sequences. Differences in the volume and conformational restrictions between the pendant crown ether moieties and the linear oligooxyethylene arms significantly influenced the synthesis and properties of the polymers. The thermal and mechanical properties of the polyamides, as well as their solubility and water uptake, were studied, with particular attention being paid to the backbone polyamide structure and to the pendant crown or podal substructure.