Photolytic and radiolytic polymerization of N-ethylmaleimide in cyclohexene

Irradiation of N-ethylmaleimide (NEMI) in cyclohexene (CH) with ultraviolet light or γ rays gives rise to polymer formation. Separation of the components by liquid chromatography and determination of their structure of pyrolysis--gas chromatography (GC)--mass spectrometry (MS) coupling, infrared spectroscopy, and 13C- and 1H-resonance spectroscopy show that the polymer produced in photolysis as well as in radiolysis consists of an almost alternating copolymer of NEMI and CH and small amounts of a NEMI homopolymer. Based on the experimental results, a radical mechanism for copolymerization and an anionic mechanism for homopolymerization are proposed