CELLULOSES, HYDRO- AND OXYCELLULOSES, AND CELLULOSE ESTERS.
L. Vignon (Bull. Soc. Chim., 1901 [3], 25, 130).
(a) Oxycelluloses from cotton, hemp, flax, and ramie.—The comparative oxidation of these celluloses, by treatment with HClO3 at 100°, gave remarkably uniform results, as shown by the following numbers, showing extreme variations: yields, 68-70 p.ct.; hydrazine reaction, N fixed 1.58-1.69; fixation of basic colouring matters (relative numbers), saffranine, 100-200, methylene blue, 100-106. The only points of difference noted were (1) hemp is somewhat more resistant to the acid oxidation; (2) the cotton oxycellulose shows a somewhat higher (25 p.ct.) cupric reduction.
(b) 'Saccharification' of cellulose, cellulose hydrates, and hydrocellulose.—The products were digested with dilute hydrochloric acid six hours at 100°, and the cupric reduction of the soluble products determined and calculated to dextrose.
| 100 grms. of | gave reducing products equal to Dextrose |
| Purified cotton | 3.29 |
| " Hydrocellulose | 9.70 |
| Cotton mercerised (NaOH 30° B.) | 4.39 |
| Cotton mercerised (NaOH 40° B.) | 3.51 |
| Cellulose reprecipitated from cuprammonium | 4.39 |
| Oxycellulose | 14.70 |
| Starch | 98.6 |
These numbers show that cellulose may be hydrated both by mercerisation and solution, without affecting the constitutional relationships of the CO groups. The results also differentiate the cellulose series from starch in regard to hydrolysis.
(c) Cellulose and oxycellulose nitrates.—The nitric esters of cellulose have a strong reducting action on alkaline copper solutions. The author has studied this reaction quantitatively for the esters both of cellulose and oxycellulose, at two stages of 'nitration,' represented by 8.2-8.6 p.ct. and 13.5-13.9 p.ct. total nitrogen in the ester-products, respectively. The results are expressed in terms (c.c.) of the cupric reagent (Pasteur) reduced per 100 grs. compared with dextrose (=17767).
| Cellulose maximum nitration (13.5 p.ct. N) | 3640 |
| Oxycellulose maximum nitration (13.9 p.ct. N) | 3600 |
| Cellulose minimum nitration (8.19 p.ct. N) | 3700 |
| Oxycellulose minimum nitration (8.56 p.ct. N) | 3620 |
The author concludes that, since the reducing action is independent of the degree of nitration, and is the same for cellulose and the oxycelluloses, the ester reaction in the case of the normal cellulose is accompanied by oxidation, the product being an oxycellulose ester.
Products of 'denitration'.—The esters were treated with ferrous chloride in boiling aqueous solution. The products were oxycelluloses, with a cupric reduction equal to that of an oxycellulose directly prepared by the action of HClO3. On the other hand, by treatment with ammonium sulphide at 35°-40° 'denitrated' products were obtained without action on alkaline copper solutions.