Abstract
Three maleimide monomers which were characterized by the presence of a OH in Nsubstituted group, , i.e. N-methylol-(MMI), N-2-hydroxyethyl-(HEMI) and N-4-hydroxyphenyl maleimide (HPMI) were copolymerized with styrene (St), vinyl acetate (VAc), methyl methacrylate (MMA) and N-vinylpyrrolidone (VPD), respectively, by radical initiator. St and VPD gave alternating copolymers with each maleimide derivative independently of monomer feed ratio. In the case of VAc the copolymers obtained were always rich in the imides. The reactions of MMA with imide derivatives were found to be a typical random copolymerization.
There were remarkable differences in the reduced viscosities between the copolymer St HPMI and St-MMI or between MMA-HPMI and MMA-MMI according to the monomer feed ratios, but between VAc-HPMI and VAc-HEMI only some difference was observed which was explained by the high reactivity of VAc radical.
In the copolymerization of every monomer pair, the reduced viscosities of resulting polymers turned to decrease in the region of excess maleimide derivatives. This phenomenon was attributed to a large quantity of OH-groups in the reaction medium.
The Q, e values of maleimide derivative were as follow,
MMI: Q=0.49, e=1.32 HEMI: Q=0.43, e=1.42 HPMI: Q=0.80, e=1.39
