Partially fluorinated and ammonium‐functionalized terpolymers: Effect of aliphatic groups on the properties of anion conductive membranes. Issue 8 (9th February 2017)

• Record Type: Journal Article
• Authors: Ono, Hideaki; Miyake, Junpei; Miyatake, Kenji
• Is Part Of: Journal of polymer science. Volume 55:Issue 8(2017)
• Page Start: 1442
• Page End: 1450
• Publication Date: 2017-02-09
• Subjects: ammonium groups -- ion conductive polymers -- ion exchangers -- membranes -- polyaromatics -- terpolymers; 547
• DOI: 10.1002/pola.28513
• Languages: English
• ISSNs: 0887-624X

Abstract

ABSTRACT: Synthesis and properties of a series of ammonium‐containing terpolymers (QPAF‐3) as anion conductive membranes are reported. The QPAF‐3s composed of perfluoroalkylene, alkylene, and ammonium‐functionalized phenylene groups without heteroatom linkages in the main chain were synthesized via nickel‐mediated polycondensation reaction, followed by chloromethylation, quaternization, and ion exchange reactions. Self‐standing, bendable membranes were obtained by solution casting. The QPAF‐3 membrane with optimized terpolymer composition and ion exchange capacity (1.46 meq g −1 ) showed high hydroxide ion conductivity (123 mS cm −1 in water at 80 °C). The alkaline stability test in 1 M KOH for 1000 h at 80 °C and the post‐test analysis with IR spectra and tensile strength suggested that ammonium groups were likely to be decomposed while the polymer main chain was chemically more robust. The presence of the alkylene groups in the terpolymers lowered solubility, glass transition temperature, and elongation property of the resulting membranes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2017, 55, 1442–1450 Abstract : A series of anion conductive aromatic terpolymer membranes (QPAF‐3) containing perfluoroalkylene, alkylene, and ammonium‐functionalized phenylene groups without heteroatom linkages in the main chain was synthesized. The presence of the alkylene groups did not practically affect the hydroxide ion conductivity and alkaline stability. The QPAF‐3 (3) membrane with optimized terpolymer composition showed high hydroxide conductivity (123 mS cm −1 in water at 80 °C) and chemical robustness of the main chain under accelerated alkaline stability test conditions (1 M KOH for 1000 h at 80 °C).