GB286332A - The manufacture of carbohydrate derivatives - Google Patents

Abstract

286,332. Harrison, W. Oct. 30, 1926. Starch and other carbohydrate derivatives. - Stable and permanent derivatives of starch and other carbohydrates are obtained by oxidizing a carbohydrate compound containing the CSS group, in the presence of an organic derivative of ammonia in which at least one atom of hydrogen is reactive ; one or both of the other hydrogen atoms may be replaced by an alkyl, aryl, or aralkyl group, or by an oxy- or hydroxy-, alkyl-, aryl-, or aralkyl group. The carbohydrate compound and the ammonia derivative may be mixed together before the addition of the oxidizing agent. Suitable ammonia derivatives are :- alkylamines, arylamines such as aniline, aralkylamines, acid amides such as acetamide. benzamide or phthalimide, amino acids such as aminoacetic acid, amidines. urea and its derivatives, cyanamide, dicyanodiamide, dicyanamide, guanidine and its derivatives, urethanes, and thiourea and its derivatives. The reaction may be carried out under alkaline, neutral or faintly acid conditions; and it may be conducted at normal temperature or at raised temperatures up to 100‹ C. ; when carried out at low temperature the products appear to be derivatives of diimido carboxylic disulphide, whereas at 100‹ C. they appear to be derivatives of benzothiazol. The oxidizing-agents used are such as will oxidize sulphuretted hydrogen ; they may be ferricyanides, bichromates, chlorates, hypochlorites, peroxides, nitrous acid, sulphurous acid, ferric salts, and air or oxygen with or without oxygen carriers; when air or oxygen is employed, this must be blown through the mixture, or the oxygen may be used in the nascent state as produced by electrolysis of the solution. In examples, the starting material is starch xanthogenate, and the reaction is carried out either in the alkaline solution, or after neutralizing with acetic, carbonic, sulphurous or phosphoric acid; the ammonia derivative is aniline, toluidine, methylaniline, or urea ; the products either separate out of themselves, or are separated out by acidifying the mixture ; and either during or after the formation of the carbohydrate compound it is treated with acetone, carbon disulphide, sodium sulphite, or other solvent for sulphur. The products obtained may be dissolved in caustic alkalies, or in cellulose solvents such as zinc chloride, sulphuric acid, and ammoniacal copper solution; and they may be worked up into films, filaments, filling materials. &c. Specifications 27732/12, [Class 2 (ii), Cellulose &c.] ; and 286,331 are referred to.