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Title: Phosphonium‐based polyelectrolyte networks with high thermal stability, high alkaline stability, and high surface areas

Phosphonium‐containing polyelectrolyte networks (PENs) (P1P4) were prepared by cyclotrimerization of bis(4‐acetylphenyl)diphenylphosphonium bromide (M1) and 1,4‐diacetylbenzene (M2) withp‐toluene sulfonic acid in variousM1:M2ratios (1,0, 1:1, 1:2, and 1:4). The relative abundance of the PAr4+units in each PEN was demonstrated to influence thermal stability, alkaline stability, water uptake, surface area, and CO2uptake in predictable ways. Impressively, PENs with NTf2counterions (Tf = CF3SO3) did not exhibit 5% mass loss until heating above 400 °C. Alkaline stability, tested by challenging a PEN with 6MNaOH(aq) at 65 °C for 120 h, increased with increasing PAr4+content, which reflected the enhanced reactivity of the HOanion in more hydrophobic materials (i.e., PENs with lowerM1:M2ratios). The specific surface areas estimated by Brunauer‐Emmett‐Teller (BET) analysis for these PENs were above 60 m2/g under N2and nearly 90 m2/g under CO2. Notably,P3(in which 33% of monomers comprise a phosphonium moiety) exhibited a CO2uptake affinity of one CO2molecule adsorbed for every phosphonium site. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2019,57, 598–604

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Author(s) / Creator(s):
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Polymer Science Part A: Polymer Chemistry
Page Range / eLocation ID:
p. 598-604
Medium: X
Sponsoring Org:
National Science Foundation
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