 | In contrast to other cellulose-based products, in the case of nitrocellulose the degree of substitution is indicated indirectly via the nitrogen content (in relation to dry substance). Theoretically, a nitrogen content of 14.14% is possible (all three positions in an anhydroglucose unit are converted, i.e. substituted).
In actual practice, the nitrogen content cannot exceed around 13.6 to 13.8%. The nitrogen content of Walsroder Nitrocellulose and Walsroder NC-Chips for coatings and printing inks is between 10.7 and 12.3%. Nitrocellulose with a nitrogen content above 12.6% is classed as an explosive.
The degree of substitution determines the solubility of Walsroder Nitrocellulose and Walsroder NC-Chips in organic solvents. Walsroder Nitrocellulose and Walsroder NC-Chips are divided up according to their solubility as follows:
| A grades | |
| Nitrogen content: 10.7 - 11.3% | Soluble in alcohol, esters, ketones and glycol ethers. |
| AM grades | |
| Nitrogen content: 11.3 - 11.8% | Soluble in esters, ketones and glycol ether; highly compatible and dilutable with alcohols. |
| E grades | |
| Nitrogen content: 11.8 - 12.3% * | Soluble in esters, ketones and glycol ethers; dilutable with alcohols. |
* The maximum permissible nitrogen content is governed by national legislation and varies from country to country between 12.2 % and 12.6 %.
The degree of substitution is coded differently in various regions:
Europe | US America / Asia | UK / India / Asia |
A | SS | M |
AM | AS | L |
E | RS | H |
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