Membranes, phosphonic acid groups

Schmidt-Naake, G., Bohme, M. and Cabrera, A. 2005. Synthesis of proton exchange membranes with pendent phosphonic acid groups by irradiation grafting of VBC. Chemical Engineering and Technology 28 720-724. 

To prepare new and inexpensive membranes, various trials have been made 196 sulfonated aromatic polyether membrane such as polyether ketones (PEEK),197 sulfonated polysulfone198 and membranes from sulfonated polyphenylene sulfide,199 phosphoric acid-doped polybenzimidazole, (PBI),200 polybenzimidazole having sulfonic acid groups,201 polybenzimidazole with phosphonic acid groups,202 a blend membrane of polybenzimidazole and sulfonated polysulfone,203 sulfonated phosphazene polymer.204... 

Several methods have been shown to induce charge-based selectivity in a polysaccharide membrane. Methods explored by Saxena et al. were to functionalize chitosan with either phosphonic acid groups or quaternary ammonium groups and crosslink with poly(vinyl alcohol) as shown in Figure 3.5 [10a]. 

Proton-Conducting Polymers and Membranes Carrying Phosphonic Acid Groups... 

S. Banerjee, K.K. Kar, M.K. Ghorai, S. Das, Synthesis of polyether ether ketone membrane with pendent phosphonic acid group and determination of proton conductivity and thermal stability, High Perform. Polym. 27 (2015) 402-411. 

A. L. Rusanov, P. V. Kostoglodov, M. J. M. Abadie, V. Y. Voytekunas and D. Y. Likhachev, Proton-Conducting Pol5mers and Membranes Carrying Phosphonic Acid Groups, in Fuel Cells II, Advances in Polymer Science,... 

Tayouo R, David G, Ameduri B, Roziere J, Roualdes S (2010) New fluorinated polymers bearing pendant phosphonic acid groups. Proton conducting membranes for fuel cell . Macromolecules 43 5269. 

Proton-Conducting Polymers and Membranes Carrying Phosphonic Acid Groups 129 Table 1 Properties of the polyethers of general formula... 

In order to obtain the membrane in which both conductivity and solubility coexist, copolymers containing sulfonic and phosphonic acid groups at the same time were prepared (Schemes 9,10) [55]. As dicarboxyUc adds containing sulfonic acid groups 5-sulfoisophthalic acid monosodium salt (SIA) and 2-sulfoterephthalic acid monosodium salt (STA) were used. 

Conversion of these pendent dialkyl phosphonate groups to phosphonic acid groups is a potential route to proton-conductive fuel cell membranes. 

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