Surface reaction of organic materials by laser ablation of matrix-isolated photoreactive aromatic azido compound

Abstract

The ablation of pentafluorophenylazide (FPA), which was isolated in a chemically inert C 6F 14 solid matrix at 85 K, was carried out by irradiation with a KrF excimer laser in vacuum. A large amount of pentafluorophenylnitrene (FPN) was ejected explosively as fragments from the matrix during irradiation. The photolysis of FPA was followed by mass spectrometry, UV–visible absorption spectroscopy and optical emission spectroscopy. It was found that the fragment beam of photolysed FPA was useful for the surface chemical modification of organic materials, such as a poly(ethylene terephthalate) film and alkylthiol monolayer. Surface analyses of these materials by X-ray photoelectron spectroscopy and Fourier transform IR reflection absorption spectroscopy indicated that FPN was immobilized on the surface through chemical bonding. The modified surface showed hydrophobic properties due to a decrease in surface polarity by the deposition of the fluorinated group of FPN. © 1997 Elsevier Science S.A.