TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compound: The nickel compound is nickel (0) bis (cyclooctadiene) or halogenated nickel.Preferred Method: The sulfonyl chloride-containing benzene compound of formula (8) and alkali-metal compound of formula (10): A-M are reacted to obtain the dihalo benzene compound.M=alkali metal atom.    TECHNOLOGY FOCUS - POLYMERS - Preferred Method: A polyarylene containing repeating unit of formula (2), is obtained by polymerizing monomer composition containing the dihalo benzene compound of formula (1) and optionally aromatic compound of formula (5): X2-(((Ar1-Y1)a-Ar2-Z1-((Ar3-Y2)b-Ar4-Z2)c)n-(Ar1-Y1)a-Ar2)-X2, or dihalo compound of formula (6): X3-Ar5-X3, in presence of nickel compound and in copresence of nitrogen-containing bi-dentate ligand and zinc. The polyarylene further contains repeating unit of formula (3): -(((Ar1-Y1)a-Ar2-Z1-((Ar3-Y2)b-Ar4-Z2)c)n-(Ar1-Y1)a-Ar2)- or repeating unit of formula (4): -Ar5-. The polyarylene containing repeating unit of formula (7) is obtained by hydrolyzing the polyarylene having repeating unit of formula (2) in presence of acid or alkali, preferably by reacting the polyarylene and alkali-metal halide or halogenated quaternary ammonium, and subsequently acid treating the product.A,k=same as defined above;R1=same as defined above, preferably H;m=same as defined above, preferably 1;a-c=0 or 1;n=5 or more;Ar1-Ar5=bivalent aromatic group chosen from (1-20C alkyl, 1-20C, 2-20C acyl) (un)substituted by fluorine atom, cyano, 1-20C alkoxy, 6-20C aryl and/or 6-20C aryloxy group, and (6-20C aryl or 6-20C aryloxy group) (un)substituted by fluorine atom, cyano, 1-20C alkoxy and/or 6-20C aryloxy group;Y1,Y2=single bond, carbonyl, sulfonyl, 2,2-isopropylidene, 2,2-hexafluoro isopropylidene or fluorene-9,9-diyl;Z1,Z2=oxygen or sulfur;andX2,X3=chlorine, bromine or iodine. Preferred Definitions:    m=1;and    R1=H.    EXAMPLE - 2,2-Dimethyl propanol (in g) (44.9) was dissolved in pyridine (145) and reacted with 2,5-dichloro benzene sulfonic acid chloride (100) at 0degreesC for 1 hour. Ethyl acetate (740 ml) and 2 mol% hydrochloric acid (740 ml) were added and stirred. An organic layer was separated, washed, distilled, refined and dried to obtain white solid of (2,2-dimethyl propyl)-2,5-dichloro benzene sulfonic acid at a yield rate of 82.1%. Anhydrous nickel salt (1.62) and dimethyl sulfoxide (15 ml) were mixed at 0degreesC. 2,2'-Bipyridine (2.15) was added and stirred for 10 minutes to obtain nickel containing solution. (2,2-dimethyl propyl)-2,5-dichloro benzene sulfonic acid (1.49), zinc powder (1.23) and solution of Sumica excel PES 5200P (RTM: polyether sulfone having weight average molecular weight of 94000 and number average molecular weight of 40000) (0.5) dissolved in dimethyl sulfoxide (5 ml) were added and polymerized at 70degreesC for 4 hours. The solid was made to deposit by adding and stirring methanol (60 ml) and 6 mol/l hydrochloric acid (60 ml). The solid was filtered and dried to obtain polyarylene having repeating units of formulae (A,B), weight average molecular weight of 191000 and number average molecular weight of 69000, at a yield rate of 99%.