GB387924A - Improvements in or relating to the manufacture of dithiocarbamates - Google Patents

Abstract

Dithiocarbamates are manufactured by reacting two or more molecular proportions of a primary or secondary amine with one of carbon disulphide, the starting materials being in a gaseous or vaporous state or in a state of very fine subdivision and diluted with a carrier gas which does not react with the starting materials or the reaction product. The process is advantageously carried out by separately vaporizing the carbon disulphide and amine by passing gases through them and then bringing the vapour-laden gases together. According to the vapour pressure of the amine and the dilution desired, larger or smaller quantities of carrier gas are employed. The vaporization may be effected at ordinary, reduced or elevated temperatures according to the vapour pressure of the starting materials. In order to secure a constant output the vaporization is effected in baths of accurately adjusted temperature. Amines which are gaseous at ordinary temperatures are simply mixed with the carrier gas. The process may also be carried out by bringing the starting materials into vapour form by distillation or in the case of difficultly vaporizable amines effecting very fine subdivision by means of atomizing jets, and then diluting with the gases. Suitable carrier gases are nitrogen, hydrogen, carbon monoxide and water gas, also air if care is taken to prevent ignition. The gases after leaving the reaction can be conducted again through the vaporizer. The process may be carried out at ordinary, increased or reduced pressure. If the reaction is too vigorous it can be moderated by cooling. The products, which are precipitated in a very pure, finely pulverulent form and which are of a white colour, are advantageously suited for the rubber industry particularly where colourless or specially coloured kinds of rubber are required. In examples: (1) commercial piperidine and carbon disulphide are vaporized by passing water gas through them and reacted to form piperidine pentamethylenedithiocarbamate; (2) cyclohexylamine and carbon disulphide are vaporized by means of nitrogen and reacted to produce cyclohexylamine cyclohexyldithiocarbamate; (3) dibutylamine (at 80 DEG C.) and carbon disulphide are vaporized by means of hydrogen and reacted to form dibutylamine dibutyldithiocarbamate; (4) dicyclohexylamine is atomized by means of water gas through a nozzle into a reaction chamber where it reacts with a mixture of carbon disulphide and water gas to yield dicyclohexylamine dicyclohexyldithiocarbamate.ALSO:Dithiocarbamates, obtained by reacting two or more molecular proportions of a primary or secondary amine with one of carbon disulphide, the starting materials being in a gaseous or vaporous state or in a state of very fine subdivision and diluted with a carrier gas which does not react with the starting materials or the reaction product, are, on account of their white colour, advantageously suited for the rubber industry, particularly where colourless or specially coloured kinds of rubber are required.