Patent GB-800478-A (GB)
Title: Improvements in and relating to the formation of alkali-soluble cellulose ethers
Inventor: WEISBERG HARRY
IPC: D06M11/48
Filed: 1955-10-27
Abstract: Cellulose material is treated with a strong alkali solution and with acrylonitrile to form a cyanoethylated product which is then treated with either periodic acid or chromic acid.  The material, which may be in fibrous, non-fibrous, woven or felted form, may be cotton, linen, ramie, jute, regenerated cellulose, or mixtures thereof, or wood fibre or pulp, and the treatment of fibrous material is such that a substantial proportion of the tensile strength of the untreated material is retained.  The treatments with the alkali, which may be sodium, potassium or lithium hydroxide, benzyl trimethyl ammonium hydroxide or dibenzyl dimethylammonium hydroxide, and with acrylonitrile, which may be in aqueous solution of strong hydroxide or solution in benzene, toluene, xylene, carbon tetrachloride, solvent naphtha, cyclohexane or mixtures thereof, may be in either order, the first treatment being followed by washing and, in the case of initial alkali treatment, by neutralization with sulphuric, hydrochloric or acetic acid.  The alkali solution may be at a concentration of 3 to 50 per cent by weight and a temperature of -25 DEG  C. to boiling, and the treatment therewith may be for a period of at least one minute.  The acrylonitrile treatment, which may be at a temperature from 0 DEG  C. to boiling, is such that the treated material contains from 0.5 to 12.5 per cent by weight of nitrogen, and the periodic or chromic acid treatment is for a period of a few seconds to 24 hours at a concentration of 0.5 to 50 per cent by weight and from room temperature to boiling.  The product may be further treated at temperatures up to boiling with a solution of sodium formate, sodium oxalate, potassium citrate, lead acetate or uranium acetate in the presence of acetic, oxalic, boric or citric acid to reduce its flammability.  Treated fabrics may be used as a backing fabric on lace of cotton, silk or wool or metal tinsel and subsequently dissolved away completely in an alkali hydroxide solution, which may contain hydrogen peroxide. To improve the hand of treated fabrics, the acrylonitrile bath may also contain succinonitrile, beta-chloropropionitrile, or adiponitrile.  Examples relate to the treatment of cotton cheesecloths and fabrics.ALSO:Cellulose material is treated with a strong alkali solution and with acrylonitrile to form a cyanoethylated product which is then treated with either periodic acid or chromic acid.  The material, which may be in fibrous, non-fibrous, woven or felted form, may be cotton, linen, ramie, jute, regenerated cellulose or mixtures thereof, or wood fibre or pulp, and the treatment of fibrous material is such that a substantial proportion of the tensile strength of the untreated material is retained.  The treatments with the alkali, which may be sodium, potassium or lithium hydroxide, benzyl trimethyl ammonium hydroxide or dibenzyl dimethylammonium hydroxide, and with acrylonitrile, which may be in aqueous solution of strong hydroxide or solution in benzene, toluene, xylene, carbon tetrachloride solvent naphtha, cyclohexane or mixtures thereof, may be in either order, the first treatment being followed by washing and, in the case of initial alkali treatment, by neutralization with sulphuric, hydrochloric or acetic acid.  The alkali solution may be at a concentration of 3 to 5 per cent by weight and a temperature of - 25 DEG  C. to boiling, and the treatment therewith may be for a period of at least one minute. The acrylonitrile treatment, which may be at a temperature from 0 DEG C. to boiling, is such that the treated material contains from 0.5 to 12.5 per cent by weight of nitrogen, and the periodic or chromic acid treatment is for a period of a few seconds to 24 hours at a concentration of 0.5 to 50 per cent by weight and from room temperature to boiling.  The product may be further treated at temperatures up to boiling with a solution of sodium formate, sodium oxalate, potassium citrate, lead acetate or uranium acetate in the presence of acetic, oxalic, boric or citric acid to reduce its flammability.  Treated fabrics may be used as a backing fabric on lace of cotton, silk or wool or metal tinsel and subsequently dissolved away completely in an alkali hydroxide solution, which may contain hydrogen peroxide. To improve the hand of treated fabrics, the acrylonitrile bath may also contain succinonitrile, beta-chloropropionitrile or adiponitrile.  Examples relate to the treatment of cotton cheesecloths and fabrics.