Homopolymers and copolymers of ethyl and butyl methacrylates with N-phenylmaleimide, N-(4-chlorophenyl)maleimide, and N-(4-bromophenyl)maleimide were synthesized by free-radical bulk polymerization with benzoyl peroxide as the initiator. The content of imide in the copolymers was about 5-10 or 7.5 wt %. The homopolymers and copolymers were irradiated with ultraviolet (UV) light in a climatic test chamber for various periods to study their aging behavior. After 100, 250, and 500 h, the structure, thermal stability, chemical resistance, and some physicomechanical properties were examined. The influence of UV radiation time on structure and the investigated properties of the homopolymers and copolymers were studied. The experimental results indicate that all investigated copolymers were resistant to UV radiation after 500 h.