959857-27-3Relevant articles and documents
Synthesis and properties of new fluorinated polymers bearing pendant imidazole groups for fuel cell membranes operating over a broad relative humidity range
Frutsaert, Guillaume,Delon, Louis,David, Ghislain,Ameduri, Bruno,Jones, Deborah J.,Glipa, Xavier,Roziere, Jacques
, p. 223 - 231 (2010)
New alternating copolymers comprising a chlorotrifluorinated backbone and midazole-terminated pendant ethylene oxide groups have been prepared with a view to their use as a component of proton-conducting membranes in polymer electrolyte fuel cells. A vinyl ether containing an imidazole (Imi) function protected by a benzyl group (BVI) was first synthesized in a three-step reaction. It was then copolymerlzed in solution with chlorotrifluoroethylene (CTFE) by conventional radical copolymerization leading to alternating poly(BVI-altCTFE) copolymers in good yields. Deprotection of the benzyl group under hydrogen produced a chlorotrifluorinated poly (Imi-alt-CTFE) copolymer. The polymer was subsequently used to form blend membranes with sulfonated poly(ether ether ke-tone) (sPEEK). The conductivity of blend membranes of poly (Imi-alt-CTFE) with sPEEK lies in the range of 4-10 mS cm-1 at 40-70 °C and, for blend membranes rich in poly(Imi-alt-CTFE), is little dependent on relative humidity between 30 and 100%. It Is surmised that the polymer and membrane composition favor microstructural phase separation into chlorotrifluorlnated polymer backbone domains and regions in which imidazole groups are clustered.
