The present invention relates to a process for the preparation of a sulfonated polyarylene ether sulfone polymer (sP) by converting a reaction mixture (RG) which comprises, among others, at least one non-sulfonated aromatic dihalogen sulfone, at least one sulfonated aromatic dihalogen sulfone and at least one aromatic dihydroxy component comprising trimethylhydroquinone. The present invention furthermore relates to a sulfonated polyarylene ether sulfone polymer (sP) obtainable by the inventive process and to its use in a membrane (M). Furthermore, the present invention relates to a membrane (M) comprising this sulfonated polyarylene ether sulfone polymer (sP) and to a method for the preparation of the membrane (M).