Photophysics of Polycyanate Resin and Triazine Compounds.

Abstract : Dicyanate ester resins have a strong fluorescence and phosphorescence emission. In this work, we report fluorescence and UV spectroscopic characterization of triazine compounds, and identify that the strong fluorescence emission comes from substituted triazine rings which are formed during the cure reaction of polycyanate resins. A series of model compounds were investigated. The results show that substituted triazine rings have similar fluorescence emission to triazine vapor. The emission at 350nm corresponds to sharp emission (335nm) in triazine vapor, and that at 420nm to broad emission (395nm). The large aromatic substituent enhances broad emission which corresponds to the singlet-triplet coupling, and solvation decreases it. When samples are photo or thermally excited, the coupling states start to interact with environment and split to the original states. The split depends on excitation time, concentration and polarity of media.