TECHNOLOGY FOCUS - POLYMERS - Preparation (Claimed): Preparation of (I) comprises (a) reacting a compound of formula (-(E1X2-P1-Q1-P2)-.....-(E2-P3-Q2-P4)-) (II) with a compound of formula (X2-A-CF2-CF2-Z1) (III) to form a compound of formula (-(E1(-A-CF2-CF2-Z1)-P1-Q1-P2)-......-(E2-P3-Q2-P4)-) (IV) and (b) adding protogenic groups to moiety E1 and/or E2 to form (I); or (aa) adding a protogenic group to moiety E1 and/or E2 in (II) to form a compound of formula (-(E1(-A-CF2-CF2-Z1)(Z2)d-P1-Q1-P2)i-......-(E2(Z3)f-P3-Q2-P4)j-) (V) and (bb) reacting (V) with the compound (III) to form (I). Preferred Process: The compound (IV) (in step (b)) or the compound (II) (in step (aa)) is treated with a sulfonating agent comprising chlorosulfonic acid, oleum and/or sulfur dioxide. Preferred Definitions:    E1, E2 = phenyl, biphenyl, (1,1',4',1'')terphenyl, naphthyl, phenanthrenyl, phenylsulfonyl-phenyl, dimethyl(diphenyl)silanyl, 1,4-diphenoxyphenyl, 9,9-diphenylfluorenyl, diphenylmethanone, diphenylphosphorylphenyl, (1-methyl-1-phenyl-ethyl)phenyl, ((E)-1-methyl-2-phenyl-vinyl)phenyl, phenoxyphenyl, (1-phenylcyclohexyl)phenyl or phenylsulfanylphenyl group;    Q1, Q2 = 1,1,2,2,3,4-hexafluoro-cyclobutan-3,4-diyl or 1,1,2,3,3,4-hexafluoro-cyclobutan-2,4-diyl;    A-CF2-CF2-Z1 = -(CF2-CF2)p-O-(CF2-CF(CF3))a-(O-CF2)b-(CF2)c-SO3H or -CF2-CF2-O-CF2-CF2-Z1;    a, b, c, p = 1-10; and    d, f = 0-4.    EXAMPLE - A magnetic stir bar and then the perfluorocyclobutyl polymer polymerized from biphenyl perfluorocyclobutane (PFCB) oligomer and a hexafluoroisopropylidene-bis-triflurovinyl ether monomer (5 g) were added to a screw-cap jar with a lid. Methylene chloride (100 ml) was added and the polymer was rapidly dissolved with stirring within 1 hour. After 19 hours, iron powder was added, and the stirring speed was adjusted and maintained to keep the iron powder dispersed throughout the liquid. The mixture appeared gray. Bromine (3.4-5 g) was added, and the reaction mixture was stirred for 19 hours at 23 degrees C. Sodium bisulfate (10 g) in water (90 g) was then added and the mixture turned from a yellow-red-brown color to white. The mixture was transferred to a separatory funnel and the aqueous layer is removed and discarded. The methylene chloride layer was washed with 100 ml portions of water and the methylene chloride layer was then pressure filtered. The methylene chloride layer was added portion-wise to methanol (2 l), and the coagulated polymer was isolated by filtration. The white, flocculated polymer was washed with distilled water. The polymer was then washed with methanol (2 l), and dried under vacuum at 60 degrees C. The polymer can be further purified, vacuum dried at 60 degrees C and worked up to give PFCB-perfluorinated sulfonic (PFSA) ionomer (TRJ3058-3.5Br-PFSA). A film of a long side chain PFCB-PFSA ionomer (TRJ3058-3.5Br-PFSA with an ion exchange capacity of 1.30 milli equivalent, 1.561 g), methylene chloride (31.22 m), and chlorosulfonic acid (6.059 g) were added to a screw-cap jar. The lid was secured and placed on a roll mill for 75 minutes. The liquid was decanted off and the film was boiled in water (1 l) for 1 hour, filtered, and dried to yield 1.53 g of powder. The polymer in N,N-dimethylacetamide at 10 wt.% solids was coated on glass and heated at 80 degrees C until dry.