Compositions and methods for semicrystalline poly(aryl ether ketone) copolymers incorporating 2-benzimidazolinone and hydroquinone as comonomer units with 4,4′-dihalobenzophenone, and compositions and methods for semicrystalline poly(aryl ether ketone) copolymers incorporating 2-benzimidazolinone and hydroquinone as comonomer units with 1,4-bis(4-dihalobenzoyl)benzene are described herein. The copolymers have advantageous properties, particularly in terms of their glass transition temperatures (Tg), crystallization temperatures from melt (Tc), melting temperatures (Tm), crystallinity and chemical resistance. The copolymers are suitable for manufacturing high temperature and chemical resistance molded systems and other articles of manufacture via injection molding, extrusion, compression molding, thermoforming and additive manufacturing.