On cyanogen photopolymerization

Cyanogen photopolymer was prepared by irradiating its solution in polar solvents such as tetrahydrofuran (THF). methanol and ethanol and non petal aliphatic solvent with UV light of a high pressure mercury lamp (main emission: lambda > 270 nm) and by sunlight irradiation (lambda > 300 nm). Thr resulting photopolymers were black tarry projects. When hexane was used as solvent. the photoproduct was a viscous oil. Elemental analysis showed incorporation of solvent molecules in the: photopolymer. Photopolymer produced in THF can be represented by the minimal formula [(C2N2)(CH2CH2O)](X), while that produced in methanol by the formula [(C3N3)(OH)](X). All products were studied by Fourier transform-infrared (FT IR) and electronic spectroscopy and a model paracyanogen compound was prepared from 2,4,6-tricyano-1,3,5-triazine. Based on the data generated it has been shown that cyanogen photopolymer has a polypyrazino pyrazine structure with 1,2,4-triazine and cyano end group. It call be considered a pentamer of cyanogen. Triazine-based paracyanogen is an isomer of cyanogen photopolymers as confirmed by elemental analysis but FT-IR and especially electronic spectroscopy permit its differentiation from cyanogen photopolymers. A short discussion on cyanogen photopolymers in some bodies of the solar system has been included. (C) 1999 Elsevier Science Ltd. All rights reserved.