REACTIVITY IN RADICAL POLYMERIZATION OF N-SUBSTITUTED MALEIMIDES AND THERMAL-STABILITY OF THE RESULTING POLYMERS

The effect of N-substituents on the radical polymerization of N-substituted maleimides (RMI) was investigated. The polymerization reactivities, i.e. yield and molecular weight of the polymers, were found to change depending on the structure of the N-substituents. The poly(RMI)s bearing a bulky N-substituent were confirmed to be semiflexible poly(substituted methylene)s which were soluble in many organic solvents, but did not melt below their decomposition temperatures. From thermogravimetric analysis determined in a nitrogen stream, no weight-loss of poly(RMI) was observed at temperature below 300°C, and the maximum decomposition temperature was 400-440°C, except for N-tert-alkyl substituted derivatives which decomposed at 240-280°C via a two-step reaction. © 1990 Springer-Verlag.