Bismaleimides bearing electron-donating chromophore moieties, A (=)-D (*)-A (=) type monomers, i.e. N,N-bis(4-maleimidophenyl)methylamine (BMIPMA), N,N-bis(4-maleimidophenyl)aniline(BMIPA) and 2,5-bis(4-maleimido phenyl)-1,3,4-oxadiazole(BMIPODA) as well as their corresponding saturated model compounds, i.e. N,N-bis(4-succinimidophenyl)methylamine( BSIPMA), N,N-bis(4-succinimidophenyl)aniline(BSIPA) and 2,5-bis(4-succimidophenyl)-1,3,4-oxadiazole (BSIPODA) were synthesized. It was found that the fluorescence quantum yields of A (=)-D (*)-A (=) monomers were always dramatically lower than those of their corresponding saturated model compounds. These A (=)-D (*)-A (=) bismaleimides possess a strong SSQE, which is attributed to an intramolecular charge transfer interaction.
Bismaleimides bearing electron\|donating chromophore moieties, i.e.N,N \|bis(4\|maleimidophenyl)\|methylamine (BMIPMA),and its saturated model compound N,N\| bis(4\|succinimidophenyl)\|methylamine(BSIPMA) were synthesized and their absorption and fluorescence behaviors were investigated. It was found that BMIPMA possess a strong fluorescence structural self\|quenching effect (SSQE).There is almost no fluorescence emission observed for BMIPMA,whereas its saturated model compound BSIPMA displays a strong fluorescence emission at the same chromophore concentration.On the basis of the SSQE,a new fluorescence approach was developed to monitor the process of the copolymerization of bismaleimides with diamines,which can directly reflect the consumption of the CC bond of maleimide unit.The results agreed well with that obtained by 1H\|NMR measurement pused.
