Patent GB-344488-A (GB)
Title: Improvements in the manufacture of organic substitution derivatives of cellulose
IPC: C08B11/155
Filed: 1929-12-02
Abstract: Cellulose esters and ethers containing the nitrile group are obtained by known esterifying or etherifying processes, in particular by treating cellulose or a cellulose derivative containing a free hydroxyl group with esterifying or etherifying agents containing the nitrile group, -CN.  Suitable agents are chloracetonitrile, cyanacetylchloride and a -or b -chlorpropionitrile.  The cellulose derivatives obtained may be subjected to reduction or hydration to give nitrogen-containing derivatives which have an affinity for acid wool dyestuffs.  In carrying out the process, the cellulose &c. may be, either simultaneously with or previously to the esterification or etherification, treated with alkali, for example, caustic soda or potash, preferably employed under concentrated conditions particularly if highly esterified or etherified products are required.  When forming ethers, the caustic soda may be used in quantities at least three times the water present which may itself be less than four times the weight of the cellulose and even 1 1/2 to 1/2 times such weight or less; and the water may be wholly or in part replaced by organic liquids, and such liquids may be used in relatively large proportions so that the reaction is carried out in suspension.  When cyanacidyl halides are employed, the treatment may be effected in the presence of organic bases such as pyridine, N-methyl piperidine, dimethyl-n-hexylamine and dimethylaniline.  As initial materials there may be used-cotton, regenerated cellulose, and wood pulps, preferably purified chemical wood pulps; cellulose derivatives containing free hydroxyl groups and also alkyl, aralkyl, oxalkyl and carboxyalkyl groups or acetyl and other acidyl groups. By the use of these derivatives as initial materials, mixed cellulose derivatives are obtained which in addition to their usual properties, exhibit an affinity for acid dyes.  Such derivatives may also be produced by subsequent etherification or esterification of products prepared according to the present process.  Similarly mixed ether-esters may be obtained by treating cellulose simultaneously or separately with a nitrile-containing etherifying agent and a nitrilecontaining esterifying agent.  The nitrile-containing cellulose derivatives may be converted into other nitrogen-containing derivatives by reduction, for example, with sodium amalgam in boiling alcohols or aqueous alcohols to give the corresponding amino-containing derivatives of cellulose; or the nitrile-containing derivatives may be hydrated or hydrolysed by boiling with water under pressure or in the presence of hydrolysing catalysts such as hydrochloric acid, hydrogen peroxide either alone or in conjunction with sodium peroxide, to give products in which amino groups are substituted for hydroxy groups in cellulose derivatives containing the same in the form of carboxy groups, which derivatives may be treated with hypochlorites or hypobromites to give simple amino derivatives; or the hydration may be carried still further to give products such as cellulose glycollic acid or cellulose malonate.  Any cellulose derivative so produced which contains primary or secondary amino groups may be alkylated, aralkylated or acylated as by treatment with alkyl or aralkyl halide or acidyl chloride or anhydride.  In examples, to a mixture of cotton linters or purified wood pulp suspended in dimethyl-n-hexylamine and nitrobenzene, is slowly added a solution of cyanacetylchloride in nitrobenzene, after which the mixture is heated to 80-90 DEG  C.; cotton linters or purified wood pulp is treated with a mixture of cyanacetylchloride, dimethyl-n-hexylamine and glacial acetic acid, and when the reaction has terminated, acetic anhydride, acetic acid and sulphuric acid are added, the final product being a mixed cellulose derivative; cotton linters or purified wood pulp is impregnated with 50 per cent caustic soda solution, then chloracetonitrile is added while heating to 60 DEG  C., and later powdered caustic soda and a further quantity of chloracetonitrile while heating to 50-100 DEG  C., with or without further such additions; the products obtained according to the first and third of the above examples are treated with hydrogen peroxide and to the mixture sodium peroxide is added slowly to prevent rise of the temperature above 35-40 DEG  C., after which the mixture is gently heated, the isolated product, which may be alkylated, aralkylated or acylated, having a pronounced affinity for acid dyestuffs; the product of the third example is hydrolysed or hydrated at 40-50 DEG  C. with 20-25 per cent hydrochloric acid or 30-40 per cent sulphuric acid to give products more soluble in aqueous acetone or aqueous alcohol than the products obtained by treatment with hydrogen peroxide; and the hydrolysis may be continued until the nitrogen content diminishes when the product contains carboxylic acid groups; to the product of the third example suspended in nearly boiling amyl alcohol, sodium amalgam is added, the isolated product finally obtained having a very pronounced affinity for acid dyestuffs.  Specification 344,480 is referred to.