GB573752A - Improvements in or relating to the production of condensation products of acetylene - Google Patents

Abstract

Polymerizable N - vinyl compounds are obtained by condensing acetylene with a body of the formula R-NH-X where R is an alkyl, aryl, acyl, aracyl or an ester radicle and X is a chlorine, bromine, iodine, nitrile, nitro, nitroaryl, or sulphonic radicle having in aqueous solution a pH less than 7. Suitable compounds are N-chloracrylamides, N-cyanacrylamides, N-nitroacrylamides, N-chlorurethanes, N-cyanurethanes, N-nitrourethanes, N-acylsulphonamides, N-alkyl- or N-aryl-nitramines and N-(nitroaryl)amines. Suitable condensing agents are preferably used such as mercuric salts, cadmium and zinc compounds and heteropolyacids; the agent may be produced in situ for instance by adding sulphuric acid to a reaction mixture containing a dissolved or suspended mercury salt. The reaction may be effected in the presence or absence of solvents, such as ketones, ethylidene diacetate and other inert oxygen-containing solvents, or the liquid reaction products remaining in the residue after the lower-boiling unsaturated reaction products have been removed by distillation. A polymerization inhibitor such as copper or a phenol may be present. Instead of employing distillation, unchanged starting material may be removed from the reaction products by aqueous alkali. In an example acetylene is introduced into a mixture of monochlorurethane, mercuric acetate, and sulphuric acid at room temperature. Vinyl chlorurethane is distilled from the product. It polymerizes to a glass-clear product.