HIGH-MOLECULAR PERCHLOROSILOXANES

The reaction of SiCl4 and O-2 in the gas phase does not lead spontaneo usly to the thermodynamically favored products SiO2 and Cl-2. At tempe ratures of about 1300 K a lot of intermediates SinOmCl4n-2m can be iso lated. Mass-spectrometric investigations show the formation of chloros iloxanes with n = 2...65 and m/n = 0,5...1,7 and molar masses up to 70 00D. These compounds - even the high molecular ones - show typical mol ecular behaviour: they are solulable in unpolar solvents like hexane a nd can be sublimed congruently. No indications could be found between the structures of Si-O-frameworks in the siloxanes and solid SiO2-modi fications.