TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The bisphenol compound is 4,4'-dihydroxy biphenyl. The alkali metal salt is potassium carbonate or sodium carbonate. The organic polar solvent is N-methyl-2-pyrrolidone, N,N-dimethyl acetamide, dimethyl sulfoxide or sulfolane.    TECHNOLOGY FOCUS - POLYMERS - Preparation: Aromatic dihalogen compound having halogen group activated by electron-attractive group, and a bisphenol compound and/or a bis thiophenol compound are reacted, such that the molar ratio of phenol compound to halogen compound is 0.8-0.99, and an oligomer of halogen group terminal is obtained. A polyphenol compound having 3 or more phenolic hydroxyl groups in a molecule, and/or a poly thiophenol compound having 3 or more thiophenol property mercapto groups, is reacted with the obtained oligomer, such that the number of moles of halogen group in oligomer is more than an equivalent mole than the number of moles of phenolic hydroxyl groups and/or thiophenol property mercapto groups, to obtain aryl ether polymer and/or aromatic thio ether polymer having a branch in a molecule.Preferred Polymer: The ratio of number of moles of structure (1) and number of moles of group (Ar5) is greater than or equal to0.2 and less than 0.7. The aromatic group (Ar5) is chosen from group of formulae (9,10).Preferred Process: The manufacturing process of the oligomer, and the reaction of oligomer with polyphenol compound are carried out in the presence of an alkali metal salt. The heating and reaction are carried out in an organic polar solvent under the atmosphere of inert gas or airflow. The ratio of number of moles of phenolic hydroxyl group and/or thio phenol property mercapto group with respect to number of moles of halogen group in oligomer is 0.2-0.6. The heating temperature is 150-250degreesC. Preferred Compound: The aromatic dihalogen compound is chosen from group of formula (16,17). The polyphenol compound or poly thiophenol compound is chosen from group of formulae (22,23).X=halogen atom of fluorine, chlorine, iodine or bromine;andY=alkali metal ion of lithium, sodium or potassium. Preferred Definitions:    Ar1,Ar2=adamantyl group of formula (8);and    m+n=integer greater than or equal to10.    EXAMPLE - 3,3'-disulfonic acid sodium-4,4'-dichlorodiphenyl sulfone (in g) (9.971), 2,6-dichloro benzonitrile (8.147), 4,4'-dihydroxy biphenyl (12.347) and potassium carbonate (10.539) were mixed in a flask. N-methyl-2-pyrrolidone (80 ml) was added and stirred at 150degreesC for 30 minutes. The temperature was raised to 195-200degreesC, to obtain an oligomer. The obtained oligomer was cooled and mixed with trithio cyanuric acid (0.152), and baked to obtain sulfonic acid group-containing polymer having logarithmic viscosity of 0.97 dl/g. The obtained polymer was dissolved in N-methyl pyrrolidone (30 ml), and the solution was coated on glass plate. The coating was dried and immersed into pure water and sulfuric acid aqueous solution. The film was dried to form ion exchange membrane having proton conductivity of 0.06 S/cm, methanol permeability of 0.2 micronsol.m-1.second-1 and output voltage of 0.42 V.