Synthesis of fluorinated block copolymer electrolyte containing quaternary ammonium base

Fluorinated block copolymers poly(2,3,4,5,6-pentafluorostyrene)- b -poly(styrene) (PFS- b -PS) synthesized by atom transfer radical polymerization was functionalized with quaternary ammonium base groups via chloromethylation of PFS- b -PS, followed by reactions with trimethylamine and ion exchange with KOH to prepare anion exchange block polymer electrolytes (AEBPEs). The challenges and limitations during the synthesis are discussed. A comparative study on the chloromethylation of PFS- b -PS with two kinds of chloromethylation agents is carried out. The thermal stability, morphology, and conductivity of the obtained AEBPEs (PFS- b -QAPS(OH)) were investigated by thermogravimetry analysis, differential scanning calorimeter, small-angle X-ray scattering, and AC impedance, respectively.