TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: 1-50 Mol% of aromatic sulfone repeating unit and aromatic ketone repeating unit has sulfonic acid or sulfonate substituent. The aromatic sulfone repeating unit is of formula (1), aromatic ketone repeating unit is of formula (2), the aromatic compound repeating unit which connects repeating units with ether linkage is of formula (3), aromatic sulfone repeating unit having sulfonic acid or sulfonate substituent is of formula (4) and aromatic ketone repeating unit having sulfonic acid or sulfonate substituent is of formula (5). The content of branching unit is 0.1-1 mol% based on aromatic compound repeating unit which connects repeating units with an ether linkage. The monomer mixture is monomer mixture comprising aromatic sulfone monomer, sulfonated aromatic ketone monomer and aromatic dihydroxy monomer, monomer mixture comprising aromatic ketone monomer, sulfonated aromatic sulfone monomer and aromatic dihydroxy monomer, monomer mixture comprising sulfonated aromatic ketone monomer, sulfonated aromatic sulfone monomer and aromatic dihydroxy monomer, monomer mixture comprising aromatic sulfone monomer, aromatic ketone monomer, sulfonated aromatic ketone monomer and aromatic dihydroxy monomer, monomer mixture comprising aromatic sulfone monomer, aromatic ketone monomer, sulfonated aromatic sulfone monomer and aromatic dihydroxy monomer or monomer mixture comprising aromatic sulfone monomer, aromatic ketone monomer, sulfonated aromatic ketone monomer, sulfonated aromatic sulfone monomer and aromatic dihydroxy monomer. The aromatic sulfone monomer is of formula (10), aromatic ketone monomer is of formula (11), aromatic dihydroxy monomer is of formula (12), sulfonated aromatic sulfone monomer is of formula (13), and the sulfonated aromatic ketone monomer is of formula (14).M1-M4=H, sodium, lithium and potassium;K'=ketone chosen from group consisting of -CO-, -CO-CO- and group of formula (A);X=-O-, -S-, -NH-, -SO2-, -CO-, -(CH3)2- or -C(CF3)2-;R1-R5=5-30C aromatic ring and 1-30C alkyl substituent containing heteroatom selected from oxygen, nitrogen or sulfur;a-c=0-4;x,x'=0-3;y,y',(x+y),(x'+y')=1-4;andY'=fluoro, chloro, bromo or iodo.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The content of polymer is 0.01-50 weight% with respect to sulfonated polysulfoneketone copolymer. The polysulfoneketone copolymer has molecular structure of formula (6) or (7). The polysulfoneketone copolymer further comprises branching unit derived from polyfunctional monomer(s) chosen from 4-((4-hydroxyphenyl)carbonyl)benzene-1,2-diol, 4-(1-(4-hydroxyphenyl)-1-(4-methylphenyl)propan-2-yl)phenol, 3,3-bis(4-hydroxyphenyl)-2,3-dihydro-1H-indol-2-one, 2-(2,4-dihydroxyphenyl)-2-methyl-3,4-dihydro-2H-1-benzopyran-4,4,7-triol, benzene-1,3,5-triol, benzene-1,2,3-triol, 4-benzoylbenzene-1,2,3-triol and 4-(1,1-bis(4-hydroxyphenyl)ethyl)phenol. The sulfonated polysulfoneketone copolymer comprises monomer mixture comprising sulfonated or unsulfonated aromatic sulfone monomer, sulfonated or unsulfonated aromatic ketone monomer and dihydroxy monomer. The branched polysulfoneketone copolymer has molecular structure of formula (8) or (9).