TECHNOLOGY FOCUS - POLYMERS - Preparation (Claimed): Preparation of (I) comprises: preparing methyl(bromotetrafluoroethoxy)benzoate (V) by reacting hydroxybenzoate (IV) and dibromotetrafluoroethanol in the presence of alkali earth metal or a precursor compound; preparing imidazole benzoate compounds of formula (VII) by reacting (V) and amine compounds of formula (VI); and preparing (I) by oxidizing (VII). Preferred Process: The preparation of (V) is performed in a polar aprotic solvent such as dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidone, dimethylformamide and dimethylacetamide. Preferred Composition: The membrane has a shape such as a film, a thin film, a flat sheet membrane, a hollow fiber membrane, a composite membrane and a tubular membrane. Preferred Components: The alkali earth metal or its precursor compound is sodium, sodium hydride, sodium hydroxide and potassium hydroxide. The poly(phosphoric acid) is used in performing the step of preparation of (VII). The zinc is used in performing the step of preparation of (I). EXAMPLE - Sodium hydride (4.8 g) was added in dimethylsulfoxide (400 ml) under nitrogen condition, and then methyl 3-(hydroxy)benzoate (30.4 g) was slowly added, followed by stirring. After hydrogen gas was generated, dibromotetrafluoroethane (52 g) was slowly added for reaction. The reaction was performed in an ice-water bath and to maintain to below 30degreesC. After 16 hours, products were placed in a separatory funnel and ethyl acetate was added, and washed with water. Water was removed with magnesium sulfate and solvent was dried under vacuum and worked up to give methyl 3-(2-bromotetrafluoroethoxy)benzoate (43 g). The methyl 3-(2-bromotetrafluoroethoxy)benzoate (33.1 g) and 3,3'-diaminobenzidine (9.6 g) were added in poly(phosphoric acid) (300 g), and reaction was stirred at 150degreesC for 16 hours. The products were dropped in distilled water and stirred overnight and the precipitates were filtered and placed in sodium carbonate solution for a day and worked up to give 5,5'-bibenzimidazole-2,2'-di(methylbrotnotetrafluoroethoxy) benzoate (26.3 g). 5,5'-bibenzimidazole-2,2'-di(methyl 3-(2-bromotetrafluoroethoxy)benzoate) (7.76 g) and zinc powder (1.44 g) were added in anhydrous di-glycol methyl ether (diglyme) (30 ml) under nitrogen condition and heated up to 100degreesC with stirring. After 16 hours, the products were filtered and dried under vacuum to obtain 5,5'bibenzimidazole-2,2'-di(methyl(trifluorovinyloxy)benzoate) (yield 68%).