Photosensitised interaction of acetylene and hydrogen sulphide

Abstract

Varying pressures of hydrogen sulphide and acetylene have been irradiated separately and together with the light from a low-pressure mercury vapour lamp. The HS radicals produced in the direct photolysis have been shown to add to acetylene to form HSCHCH˙, the process being reversible with a negative energy of activation. Ethenethiol is produced by the abstraction of hydrogen from hydrogen sulphide by this radical. A rapid polymerisation of ethenethiol occurs and the resulting polymer has been shown to have the general formula (C₂H₄S)_n by elemental analysis and mass spectrometry. The effects of variation of experimental parameters on the progress of these reactions are discussed.