Effect of N‐methyl amide linkage on hydrogen bonding behavior and water transport properties of partially N‐methylated random aromatic copolyamides. Issue 24 (3rd October 2014)

• Record Type: Journal Article
• Authors: Aiba, Motohiro; Tokuyama, Takahiro; Matsumoto, Hidetoshi; Tomioka, Hiroki; Higashihara, Tomoya; Ueda, Mitsuru
• Is Part Of: Journal of polymer science. Volume 52:Issue 24(2014:Dec.)
• Page Start: 3453
• Page End: 3462
• Publication Date: 2014-10-03
• Subjects: 547
• DOI: 10.1002/pola.27415
• Languages: English
• ISSNs: 0887-624X

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>The synthesis, conformational preferences, hydrogen bonding behaviors, and membrane properties of new partially <italic>N</italic>‐methylated random aromatic copolyamides were reported. These copolyamides were prepared by the low temperature polycondensations of isophthaloyl chloride with 3, 5‐diaminobenzoic acid, <italic>N</italic>, <italic>N</italic>'‐dimethyl‐4, 4'‐diaminodiphenyl ether (MDAE), and 4, 4'‐diaminodiphenyl ether. The incorporation of the <italic>N</italic>‐methyl amide linkages into the polymer backbone decreased the contents of the <italic>cis</italic> conformation in the <italic>N</italic>‐methyl amide linkages and suppressed the hydrogen bondings among the amide linkages. Furthermore, the surface hydrophilicity of the copolyamides evaluated by water contact angle measurements decreased with increasing the MDAE unit in the polymer backbone. These experimental results indicated that the suppression of the hydrogen bonding and the existence of the tertiary amide linkage in the <italic>cis</italic> conformation induced the loose packing of the polymer chains. As a result, the incorporation of the <italic>N</italic>‐methyl amide linkage increased water flux and decreased salt rejection. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. <bold>2014</bold>, <italic>52</italic>, 3453–3462</p> </abstract>