Nitrogen content of nitrocellulose

Composition of the nitrating mixture, % Composition of the spent acid, % Cellulose to acid ratio 1 j Nitrogen content of nitrocellulose. %... 

Cellulose Chemistry , London (1947), 245—47 22) B.T. Fedoroff, Rapid Method for the Determination of Nitrogen Content of Nitrocellulose by the Ferrous Ammonium Sulphate Method , PACLR 122871 (1948) 23) J. Pearson... 

The question whether the absorption of acetone vapours at 30°C was dependent on the nitrogen content of nitrocellulose was investigated by Rubenstein [43] (and Jenkins, Bennett and Rubenstein [122]). Figure 92 outlines the results the acetone to nitrocellulose weight ratio as well as the mole proportion of acetone to anhydroglucose unit ( submole of nitrocellulose ). 

Water content of nitrating acid % Nitrogen content of nitrocellulose /o Solubility % Molecular weight of nitrocellulose (from viscosity measurements)... 

T. Urbanski and Malendowicz [76] have examined the rate of decomposition of nitrocellulose by ultra-violet light. The results showed (T. Urbanski [77]) that nitrocellulose of 13.3% N undergoes decomposition expressed by an exponential equation, whereas lower nitrated nitrocotton, 11.9% of N, decomposes approximately in accordance with a linear function. Somewhat discordant results were published by Oguri, Takei and Fujita [78] who reported the fall in nitrogen content of nitrocellulose to be 1.0% N, after 3 hours irradiation, and 1.95% N after 8 hr. 

The first extensive investigations into the relation between the nitrogen content of nitrocellulose and the composition of the mixed add were carried out by Bruley (14]. They are summarized graphically in Fig. 119. 

Lunge et al. [15] examined the effect of the composition of mixed add, and the influence of the nitration temperature within the range from 0 to 80°C on the nitrogen content of nitrocellulose, the content of non-nitrated cellulose, the yield, the solubility of the products in ether-alcohol mixture and the viscosity of the acetone solution. Cotton linters were used. From these experiments it has been established that nitrocellulose containing more than 13.5% N is unstable and decomposed readily, as mentioned before. 

No. Composition of mixed acid, % Nitrogen content of nitrocellulose % Yield %... 

Schiemann and Kiihne also stated that changes in the water content of the mixed add, maintained within the limits from 3.5 to 13.5%, do not, in fact, cause appre-dable variations in the nitrogen content of nitrocellulose. 

Taking into consideration the results of experiments reported by different authors, Berl, Andress and E. Escales [31] have constructed a chart resembling Sapozhnikov s graph, to depict the relationship between the nitrogen content of nitrocellulose and the ratio of spent acid (Fig. 126). In principle the shape of the curves does not differ from those outlined in Sapozhnikov s work and a resemblance exists between those curves and the curves of nitronium ions (NOf) concentration (Fig. 125). 

The maximum nitrogen content of nitrocellulose was reached in these experiments when a 5% solutions of sodium, potassium or ammonium nitrate in nitric arid were used. The highest nitrogen percentage, i.e. 13.5%, was attained when using anhydrous salts that readily form hydrates, namely magnesium nitrate, Mg(N03)2, and sodium sulphate, NajSO ... 

Concentration of n2o4% Nitrogen content of nitrocellulose % Viscosity of a 2% solution in acetone Stability min... 

Fig. 129. Influence of the content of HNO3 in nitric acid-N204 solution in CC14 on nitrogen content of nitrocellulose. Ratio of reactants 5 60 60 x (cellulose N204 CC14 HN03) (Kenyon et al. [47]).

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