Abstract
The photo-polymerizations of N-substituted maleimide derivatives using ultraviolet irradiation in solid state and in solution have been investigated. It was confirmed that the light of near 300mμ was effective for the reaction, and the reaction is considered to proceed by free radical mechanism from the fact that the polymerization is retarded by radical scavenger. The effect of N-substituents could be observed on the rate of polymerization, but no clearelati onship between the nature of substituents and the rate could be found. The initial rate of polymerization, (Rp) 0, of N-2-acetoxyethylmaleimide in methanol was expressed as follows; (Rp)0=K·I1.0·[M]01.4
where I and [M]0, are light intensity and initial monomer concentration, respectively.
The overall activation energies of the reaction of N-methylolmaleimide in methanol and in dioxane were found to be 0.6 and 1.2 kcal/mole, respectively, indicating that the reaction rate depends only slightly on the temperature.
