Difluoro side chain type monomers and synthetic method

The present invention discloses a side chain type and synthetic methods difluoro monomer, the monomer is of the formula wherein X represents CH3 or OCH3, n is an integer of 1 to 3. The monomer 3,5-benzene bromide as starting material, after the Grignard reaction, nucleophilic addition reaction, bromination, prepared by the coupling reaction. The side chain of the invention comprises a polymerizable monomer difluoromethyl difluoromethyl group and functionalized methyl or methoxy group, after which the polycondensation reaction and conversion of functional groups can be quaternized or sulfonated polymers, the function polymers can be used as a fuel cell polymer electrolyte membrane material.