Aromatic high glass transition temperature sulfone polymer composition comprising: - at least one aromatic sulfone polymer, characterized in that at least 5 % wt of the recurring units of the aromatic sulfone polymer are recurring units, in their imide form (R1-A) and/or amic acid forms [(R1-B) and (R1-C)]: wherein: - the → denotes isomerism so that in any recurring unit the groups to which the arrows point may exist as shown or in an interchanged position; - Ar" is chosen among the following structures: with the linking groups being in ortho, meta or para position and R' being a hydrogen atom or an alkyl radical comprising from 1 with R being an aliphatic divalent group of up to 6 carbon atoms, such as methylene, ethylene, isopropylene, and mixtures thereof; or at least 5 % wt of the recurring units of the aromatic sulfone polymer are recurring units, as shown below: wherein: - Q is a group chose among the following structures: with R being: with n = integer from 1 to 6, or an aliphatic divalent group, linear or branched, of up to 6 carbon atoms; and mixtures thereof; - Ar is a group chosen among the following structures: with R being: with n = integer from 1 to 6, or an aliphatic divalent group, linear or branched, of up to 6 carbon atoms; and mixtures thereof; or at least 5 % wt of the recurring units of the aromatic sulfone polymer are recurring units chosen from: and mixtures thereof; - at least one oxide of an alkaline-earth metal or of a group 12 transition metal - at least one carboxylate of a metal, said carboxylate comprising at least 10 carbon atoms; - less than 5 % by weight, based on the total weight of the composition, of aromatic polycarbonate. - at least one aromatic sulfone polymer, characterized in that at least 5 % wt of the recurring units of the aromatic sulfone polymer are recurring units, in their imide form (R1-A) and/or amic acid forms [(R1-B) and (R1-C)]: wherein: - the → denotes isomerism so that in any recurring unit the groups to which the arrows point may exist as shown or in an interchanged position; - Ar" is chosen among the following structures: with the linking groups being in ortho, meta or para position and R' being a hydrogen atom or an alkyl radical comprising from 1 with R being an aliphatic divalent group of up to 6 carbon atoms, such as methylene, ethylene, isopropylene, and mixtures thereof; or at least 5 % wt of the recurring units of the aromatic sulfone polymer are recurring units, as shown below: wherein: - Q is a group chose among the following structures: with R being: with n = integer from 1 to 6, or an aliphatic divalent group, linear or branched, of up to 6 carbon atoms; and mixtures thereof; - Ar is a group chosen among the following structures: with R being: with n = integer from 1 to 6, or an aliphatic divalent group, linear or branched, of up to 6 carbon atoms; and mixtures thereof; or at least 5 % wt of the recurring units of the aromatic sulfone polymer are recurring units chosen from: and mixtures thereof; - at least one oxide of an alkaline-earth metal or of a group 12 transition metal - at least one carboxylate of a metal, said carboxylate comprising at least 10 carbon atoms; - less than 5 % by weight, based on the total weight of the composition, of aromatic polycarbonate.