| 摘要 |
Acrylonitrile which has been purified by distilling the "acrylonitrile oil" obtained by the method described in Specification 719,635, [Group IV (b)], in the presence of water (see Group III) is polymerized to give a product from which fibres having good tensile properties is obtained. In an example, 42 parts of the purified acrylonitrile was stirred with 247 parts of air-free distilled water, 0.233 parts of ammonium sulphate and 0.466 parts of sodium metabisulphite under reflux with continuous stirring in a stream of nitrogen for 2 hours at 60 DEG C. Specification 709,337, [Group IV (b)] is referred to and Specification 744,011 is referred to in the Provisional Specification.ALSO:Acrylonitrile suitable for conversion to polymer with satisfactory fibre-forming properties is obtained by distilling the "acrylonitrile oil" obtained by the method described in Specification 719,635 [Group IV(b)] in the presence of water, and recovering the acrylonitrile from the distillate. The oil may contain 96.5 per cent of acrylonitrile, 0.1 per cent of hydrogen cyanide, 0.04 per cent of acrolein, 2 per cent of acetonitrile and less than 1 per cent of propionitrile. The oil may be charged with water to the bottom of a still and then distilled at atmospheric, or at super-, or subatmospheric pressure, or the oil added into the column of a still with water circulating to give an acrylonitrile-water azeotrope boiling at 71 DEG C., which on standing divides into two layers the upper one of which contains 95 per cent of acrylonitrile. This may be polymerized according to the method of Group IV(a) and spun to produce filaments. Specification 709,337 also is referred to and Specification 744,011 is referred to in the Provisional Specification. |
