GB812063A - Cyanoethylation of cellulosic materials - Google Patents

Abstract

Cellulose is cyanoethylated by treating it with acrylonitrile in the presence of an aqueous solution containing the hydroxide of an alkali metal and an inorganic water-soluble salt of an alkali metal. The salts which may be used include sodium iodide, potassium iodide, sodium phosphate, sodium thiocyanate, sodium chloride, sodium sulphate and sodium bromide. Of these the first four are most active in increasing the efficiency of the cyanoethylation. The proportion of salt used may be varied over wide ranges. Thus in the case of sodium iodide the percentage used (based on the weight of dilute sodium hydroxide solution used) may range from 20 per cent or less up to 230 per cent; the optimum proportion for a reaction effected at 55 DEG C. for 45 minutes being 100 grams of sodium iodide per 100 cc. of sodium hydroxide solution. In four examples, 5 parts of cotton yarn are treated with 270 parts of an aqueous solution of 2 parts of sodium hydroxide and 10, 50, 105 and 170 parts respectively of sodium iodide for thirty minutes, and excess solution is removed. The 18.6 parts of wet cotton remaining are reacted in each case for 45 minutes at 55 DEG C. with 80 parts of acrylonitrile, the mixture is neutralized with glacial acetic acid and the cyanoethylated cotton is washed with water and dried. In a further series of examples cotton is similarly treated but potassium iodide, sodium sulphate, sodium bromide, sodium phosphate and sodium thiocyanate respectively are used in place of sodium iodide. In each case the sodium hydroxide solution used is saturated with the salt at room temperature.