STUDIES ON THE PHOTOREACTION OF POLYSILANES BY FLUORESCENCE SPECTROSCOPY

The fluorescence spectra of poly(methylcyclohexylsilane)(PCHMS) or -(m ethylphenethylsilane-co-methylcyclohexylsilane) (Copolymer) in solutio ns before and after u.v. irradiation in air were studied. The experime ntal results showed that the positions of the fluorescence peaks shift ed to a shorter wavelength and the fluorescence intensities decreased gradually with an increase of u.v. exposure time. The dependences of u .v. spectra, GPC, ESCA spectra and i.r. spectra of PCHMS or Copolymer solutions upon u.v. exposure in air indicated that these phenomena are in accordance with the processes of photodegradation and photo-oxidat ion, which led to decreasing molecular weights and the formation of si loxane structure in silicon-silicon main chains.