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Details

Autor(en) / Beteiligte
Titel
Halogen-Free Polyarylphosphonates and Polyelectrolyte Membranes for PEMFC by Nickel-Catalyzed Phosphonylation with Silylated Phosphates
Ist Teil von
  • Macromolecular rapid communications., 2006-12, Vol.27 (24), p.2065-2071
Ort / Verlag
Weinheim: WILEY-VCH Verlag
Erscheinungsjahr
2006
Link zum Volltext
Quelle
Alma/SFX Local Collection
Beschreibungen/Notizen
  • The nickel‐catalyzed arylphosphonylation with tris(trimethylsilyl) phosphite (TMSP) is applied to brominated high‐performance (HP) polymers in weakly coordinating high temperature solvents. At elevated temperatures, this affords halogen‐free, soluble, phosphonic acid‐functionalized polyelectrolytes and an unprecedented control of the degree of phosphonylation (dsP). Brominated polysulfone (PSU) of various degrees of bromination (dsBr) has been phosphonylated with TMSP in diphenyl ether at 200 °C in the presence of 1–10 mol‐% NiCl2. Upon methanolysis, arylphosphonic PSU with dsP up to 223 mol‐% is obtained in near quantitative bromine conversion. Catalyst residues are readily removed during methanolysis. This very versatile two‐step process affords soluble arylphosphonic polymers for casting tough membrane films. In contrast to sulfonated PSU, the arylphosphonic PSU membranes exhibit improved thermal and chemical stabilities, combined with far lower water swelling in accordance with the demands of polyelectrolyte membrane fuel cell (PEMFC) applications. Mass swelling (swM) in water of sulfonated (A–C) and phosphonylated PSU (D).

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