A PEEK copolymer gel comprising a blocky PEEK copolymer and a gel solvent that is a non-solvent for the blocky PEEK copolymer and a solvent for trifluoroacetyl sulfate, wherein the blocky PEEK copolymer comprises: (i) recurring unit (R PEEK) represented by the following formula: wherein - R 1 and R 2 are independently selected at each instance from the group consisting of a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or an alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine and a quaternary ammonium; - and R 3, R 4, R 5, and R 6 are independently selected at each instance from the group consisting of a hydrogen, halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or an alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine and a quaternary ammonium; - i and j are independently selected integers from 0 to 4; and (ii) recurring unit (R ∗ PEEK) represented by the following formula: wherein - i, j, R 5, R 6 and each R 1 and R 2 are identical to those selected for recurring unit (R PEEK); - L 1 is the same as R 3, -SO 3 M or -Br, - L 2 is the same as R 4, -SO 3 M' or -Br, - M and M' are independently selected from the group consisting of hydrogen, Group IA elements and alkali earth metal elements; and - at least one of L 1 and L 2 is -SO 3 M or Br. wherein the PEEK copolymer - has a degree of functionalization of at least 20%, as measured by 1 HNMR spectroscopy and - a degree of crystallinity of at least 10%, as measured by Differential Scanning Calorimetry ("DSC") using a ramp rate of 10° C/min and heating from a first temperature of 0° C to 390° C. (i) recurring unit (R PEEK) represented by the following formula: wherein - R 1 and R 2 are independently selected at each instance from the group consisting of a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or an alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine and a quaternary ammonium; - and R 3, R 4, R 5, and R 6 are independently selected at each instance from the group consisting of a hydrogen, halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or an alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine and a quaternary ammonium; - i and j are independently selected integers from 0 to 4; and - R 1 and R 2 are independently selected at each instance from the group consisting of a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or an alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine and a quaternary ammonium; - and R 3, R 4, R 5, and R 6 are independently selected at each instance from the group consisting of a hydrogen, halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or an alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine and a quaternary ammonium; - i and j are independently selected integers from 0 to 4; and (ii) recurring unit (R ∗ PEEK) represented by the following formula: wherein - i, j, R 5, R 6 and each R 1 and R 2 are identical to those selected for recurring unit (R PEEK); - L 1 is the same as R 3, -SO 3 M or -Br, - L 2 is the same as R 4, -SO 3 M' or -Br, - M and M' are independently selected from the group consisting of hydrogen, Group IA elements and alkali earth metal elements; and - at least one of L 1 and L 2 is -SO 3 M or Br. - i, j, R 5, R 6 and each R 1 and R 2 are identical to those selected for recurring unit (R PEEK); - L 1 is the same as R 3, -SO 3 M or -Br, - L 2 is the same as R 4, -SO 3 M' or -Br, - M and M' are independently selected from the group consisting of hydrogen, Group IA elements and alkali earth metal elements; and - at least one of L 1 and L 2 is -SO 3 M or Br. - has a degree of functionalization of at least 20%, as measured by 1 HNMR spectroscopy and - a degree of crystallinity of at least 10%, as measured by Differential Scanning Calorimetry ("DSC") using a ramp rate of 10° C/min and heating from a first temperature of 0° C to 390° C.