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Title: Tetraarylphosphonium perfluorocyclobutyl polyelectrolyte with low critical surface energy, high thermal stability, and high alkaline resistance
ABSTRACT

Two tetraarylphosphonium polyelectrolytes having perfluorocyclobutyl units in their backbones have been prepared in which the counteranion is either bromide (PFP·Br) or bis(trifluoromethyl)sulfonimide (PFP·NTf2). These polymers exhibit high thermal stability as assessed by thermogravimetric analysis, with a decomposition temperature of 460 °C forPFP·NTf2. Even after heating at 300 °C for 72 h,PFP·NTf2shows no signs of degradation detectable by nuclear magnetic resonance spectrometry. As is typical for many tetraarylphosphonium species, films of these polymers can be quite resistant to degradation by alkaline solution. Upon alkaline challenge by exposure to 6MNaOH at 65 °C for 24 h, for example, only 16% of the phosphonium centers inPFP·NTf2are degraded, makingPFP·NTf2one of the most alkaline‐stable phosphonium polymers to date. Despite having ionic backbones,PFP·Br andPFP·NTf2exhibit very low critical surface energies of 26.1 and 22.9 mJ m−1, respectively. These values are on par with the values for poly(vinylene fluoride) and dimethylsiloxane. Such low surface energy polycations capable of high alkaline stability may find application as components of alkaline fuel cell membranes. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2019, 57, 2267–2272

 
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PAR ID:
10459429
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Polymer Science Part A: Polymer Chemistry
Volume:
57
Issue:
22
ISSN:
0887-624X
Page Range / eLocation ID:
p. 2267-2272
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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