Polyarylethersulfone copolymer having improved hydrophilicity

A process for making a polyarylethersulfone (“PAES”) copolymer, comprising

• reacting in a reaction mixture comprising a polar aprotic solvent and in the presence of an alkali metal carbonate, a monomer mixture which contains:
• at least one dihaloalkylene oxide compound [dihalo (AO) monomer, hereinafter] being selected from the group consisting of compounds of formula (I):
• said dihalo (AO) monomer having from 5 to 9 carbon atoms in total and/or from 1 to 4 oxygen atoms in total:
• at least one dihaloaryl sulfone compound [dihalo (AS) monomer, hereinafter] of formula (V):
• at least one dihydroxy compound [dihydroxy (B) monomer, hereinafter] being selected from the group consisting of:
• tetramethyl bisphenol F,
• at least one 1,4:3,6-dianhydrohexitol selected from the group consisting of isosorbide isomannide and isodide,
• at least one alicyclic diol selected from the group consisting of 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,2-cyclohexane dimethanol, tricyclodecane dimethanol, adamantanediol, pentacyclopentadecane dimethanol, 1,3-cyclobutanediol, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol (“CBDO”),
• aromatic diols of formula (VI):
• HO—Ar3-T-Ar4—OH (VI), and
• any combination thereof,
• wherein:
• X1 and X2 in formula (I), equal to or different from each other, are independently a halogen atom;
• each of R1, R2, R3, R4, R5 and R6 in formula (I) is independently H or CH3;
• each of m and q in formula (I) is independently an integer of at least 2 and optionally at most 5, with the proviso that at least one R1 is H and at least one R6 is H;
• each of n and p in formula (I) is independently an integer of at least 1 and optionally at most 5, with the proviso that when n=2, at least one of R2 and R3 is H;
• and when p=2, at least one of R4 and R5 is H;
• r in formula (I) is 0, 1, 2 or 3;
• Ar1 and Ar2, equal to or different from each other in formula (V), and Ar3 and Ar4, equal to or different from each other in formula (VI), are independently aromatic moieties complying with any one of the following formulae (J), (J′) and (J″):
• in which each R, equal to or different from each other, is selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali metal sulfonate, alkaline earth metal sulfonate, alkyl sulfonate, alkali metal phosphonate, alkaline earth metal phosphonate, alkyl phosphonate, amine and quaternary ammonium;
• and
• in which each j, equal to or different from each other, are independently 0, 1, 2, 3 or 4,
• X and X′, equal to or different from each other in formula (V), are independently a halogen atom;
• T in formula (VI) is selected from the group consisting of a bond, —SO2—, —C(CH3)2—, —C(CF3)2—, —C(CCl3)2—, —C(═CCl2)—, —CH2—, —O—, —C(O)—, —C(CH3)(CH2CH2COOH)—, —S—, and —SO—;
• and
• wherein
• the monomer mixture contains at least 4 mol. % and up to 50 mol. % of the dihalo (AO) monomer, said mol. % being based on the combined numbers of moles of dihalo (AO) and (AS) monomers;
• the overall amount of halo-groups and hydroxyl-groups of the monomers in the monomer mixture is substantially equimolecular;
• and
• the amount of the alkali metal carbonate used in the reaction mixture, when expressed by the ratio of the equivalents of alkali metal (M) per equivalent of hydroxyl group (OH) in the dihydroxy (B) monomer [eq. (M)/eq. (OH)] is greater than 1.