A composite material, comprising: - fibers, and - a polymer matrix comprising at least one PEEK-PEoEK copolymer, the PEEK-PEoEK copolymer comprising at least 50 mol %, collectively, of repeat units (R PEEK) and repeat units (R PEoEK), relative to the total number of repeat units in the PEEK-PEoEK copolymer, wherein: (a) repeat units (R PEEK) are repeat units of formula: and (b) repeat units (R PEoEK) are repeat units of formula: wherein: each R 1 and R 2, equal to or different from each other, is independently at each occurrence selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine and quaternary ammonium, each a and b is independently selected from the group consisting of integers ranging from 0 to 4, and the PEEK-PEoEK copolymer comprises the repeat units R PEEK and R PEoEK in a molar ratio R PEEK /R PEoEK ranging from 95/5 to 5/95, wherein said polymer matrix is in contact with at least part of the surface of said fibers. - fibers, and - a polymer matrix comprising at least one PEEK-PEoEK copolymer, the PEEK-PEoEK copolymer comprising at least 50 mol %, collectively, of repeat units (R PEEK) and repeat units (R PEoEK), relative to the total number of repeat units in the PEEK-PEoEK copolymer, wherein: (a) repeat units (R PEEK) are repeat units of formula: and (b) repeat units (R PEoEK) are repeat units of formula: wherein: each R 1 and R 2, equal to or different from each other, is independently at each occurrence selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine and quaternary ammonium, each a and b is independently selected from the group consisting of integers ranging from 0 to 4, and the PEEK-PEoEK copolymer comprises the repeat units R PEEK and R PEoEK in a molar ratio R PEEK /R PEoEK ranging from 95/5 to 5/95, wherein said polymer matrix is in contact with at least part of the surface of said fibers. (a) repeat units (R PEEK) are repeat units of formula: and (b) repeat units (R PEoEK) are repeat units of formula: wherein: each R 1 and R 2, equal to or different from each other, is independently at each occurrence selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine and quaternary ammonium, each a and b is independently selected from the group consisting of integers ranging from 0 to 4, and the PEEK-PEoEK copolymer comprises the repeat units R PEEK and R PEoEK in a molar ratio R PEEK /R PEoEK ranging from 95/5 to 5/95, each R 1 and R 2, equal to or different from each other, is independently at each occurrence selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine and quaternary ammonium, each a and b is independently selected from the group consisting of integers ranging from 0 to 4, and the PEEK-PEoEK copolymer comprises the repeat units R PEEK and R PEoEK in a molar ratio R PEEK /R PEoEK ranging from 95/5 to 5/95,