Patent GB-664795-A (GB)
Title: Process for the chemical modification of cellulosic materials
IPC: D06M13/278
Filed: 1949-05-20
Abstract: Cellulose derivatives are obtained by causing cellulose or a cellulose derivative containing free cellulose hydroxyl groups to react with vinyl sulphone, (CH2=CH)2SO2, in presence of a catalyst consisting of an unreactive basic compound.  The cellulose or cellulose derivative may be in the form of fibres, yarns, or fabrics. It may be cotton, linen, wood, viscose rayon, cuprammonium rayon, saponified cellulose acetate, or a salt of cellulose xanthate. Fabric or yarn may be moistened with an aqueous solution of vinyl sulphone with or without a wetting agent and then treated with an aqueous solution of the alkaline catalyst.  The treatment may be carried out at 0-100 DEG  C., the reaction time being 2 hours to a few seconds.  The fabric or yarn may then be washed until free from catalyst and unreacted sulphone, and may then be dried.  The treated cellulose or regenerated cellulose is insoluble in cuprammonium or quaternary ammonium hydroxide solutions, e.g. tetraethyl or benzyl trimethyl ammonium hydroxide.  The treated fibres swell less than untreated fibres when immersed in water or alkali solutions.  If desired, the reaction can be carried out under anhydrous conditions or in the presence of organic solvents such as dioxane, benzene, or chloroform.  The fabric may be treated first with the alkali and then with the vinyl sulphone, or the alkali and sulphone may be applied together.  The catalyst may be sodium or potassium hydroxide, carbonate, or phosphate; an alkaline-earth metal hydroxide; or a quaternary ammonium hydroxide.  The vinyl sulphone may be used in solution in a concentrated solution of sodium chloride, sulphate, acetate, or phosphate.  With cotton fabrics caustic soda solutions of 0.1-30 per cent strength may be used, but for regenerated cellulose fabrics the caustic soda is preferably not greater than 8 per cent. The caustic soda solutions may contain sodium sulphate.  The vinyl sulphone applied may be from 0.1 per cent to 100 per cent by weight of the cellulose.ALSO:Fibres, yarns, or fabrics of cellulose or cellulose derivatives containing free hydroxyl groups are subjected to the action of vinyl sulphone (CH2=CH)2SO2, in presence of a basic compound which acts as a catalyst.  Cotton, linen, viscose rayon, cuprammonium rayon, or saponified cellulose acetate rayon, may be treated.  Yarns and fabrics are rendered resistant to shrinking, creasing, and loss of mechanically-imparted shape or form.  The treatment sets the twist in yarns and the pleats in pleated fabrics. Fabric or yarn may be moistened with an aqueous solution of vinyl sulphone, with or without a wetting agent, and then treated with an aqueous solution of the alkaline catalyst.  The treatment may be carried out at 0-100 DEG  C., the reaction time being 2 hours to a few seconds.  The material is subsequently washed until free from catalyst and unreacted sulphone, and is then dried.  The treated material is insoluble in cuprammonium or quaternary ammonium hydroxide solutions.  Treated fibres swell less than untreated fibres when immersed in water or alkali solutions.  The reaction may be carried out under anhydrous conditions or in the presence of organic solvents such as dioxane, benzene, or chloroform.  The catalyst may be sodium or potassium hydroxide, carbonate, or phosphate, or an alkaline-earth metal hydroxide, or a quaternary ammonium hydroxide. The vinyl sulphone may be used in solution in sodium chloride, sulphate, acetate, or phosphate solution.  With cotton fabrics, caustic soda solutions of 0.1-30 per cent may be used, but for regenerated cellulose fabrics the caustic soda is preferably not greater than 8 per cent.  The caustic soda solutions may contain sodium sulphate.  The vinyl sulphone applied may be 0.1-100 per cent by weight of the cellulose.  Sizing material may be incorporated with the vinyl sulphone solution or the alkaline solution, or the fabrics may be sized before treating with the vinyl sulphone.  The sizing material may be starch, dextrin, methyl cellulose, carboxy methyl cellulose, polyvinyl alcohol, gum arabic, or other vegetable gum. Part of the sulphone reacts with the cellulose and part with the sizing material so that a water-insoluble, cross-linked compound is formed.