Degree of nitration

Expt. 20. The results are not as accurate as for other expts. because of the small degree of nitration achieved. 

The danger of an explosion of a nitrated product generally increases as the degree of nitration increases, eg, trinitroaromatics are more hazardous as compared to dinitroaromatics or especially mononitroaromatics. Nitroaromatics and some polynitrated paraffins are highly toxic when inhaled or when contacted with the skin. AH nitrated compounds tend to be highly flammable. 

Degree of nitration Nitrogen content %) Typical usage... 

Nitrierungs-grad, m. degree of nitration or nitrification or nitridation. -stufe, /. stage or degree of nitration or nitridation. 

Nitrocellulose, of the resins used in these end uses and in car refinishing, is the nitrate ester of cellulose. The structure is linear and a wide range of (high) molecular weights is available as well as various degrees of nitration ... 

Many studies, primarily via X-ray patterns, have led to the following picture of NC of varying degree of nitration ... 

Included are four samples of NC of different degrees of nitration and one sample each of the high expls TNT (2,4,6-trinitrotoluene) and HMX (1,3,5,7-tetranitro-l, 3,5,7-tetrazacyclooctane). 

In Smoke. We compared the gas chromatograms of nitrosamines in matching aliquots of mainstream smoke derived from Burley type cigarettes that were identical except for the degree of nitrate fertilization during cultivation (Figure 2). This comparison supports the concept that the nitrate concentration in tobacco is a determining factor for the nitrosamine yields in the smoke. The data in Table II confirm this concept. These studies have... 

Cellulose nitrate is very easily ignited and bums very rapidly or explosively, depending on the degree of confinement, degree of nitration and state of subdivision. Unless very pure and stabilised, it deteriorates in storage and may ignite... 

Cellulose regenerated from the addition compound may demonstrate a certain degree of nitration (0.5—2.2% N). The properties of the compound are similar to those of hydrocellulose, eg, glittering fibers, increased hygro-scopicity and higher reactivity ... 

The cyclodextrins can be nitrated using conventional techniques that are used for the preparation of NC where the degree of nitration is controlled by varying the nitration conditions. The energetic organic nitrate esters used for plasticization of cyclodextrin nitrates include 1,1,1-trimethylole thane trinitrate (TMETN),... 

Smokeless propellants may be taken as another example of composite explosives. These may be either mixtures of nitrocellulose of differing degrees of nitration, partly in a colloidal and partly in a fibrous state with an admixture of the remaining solvent and a stabilizer or a solution of nitrocelluloses in carbamite (centralite) and nitroglycerine with an admixture of components such as aromatic nitro compounds, nitroguanidine, graphite etc. 

Aniline, Polynltro Derivatives. As no info is available on the analysis of these compds, we asked the opinion of Mr, F. Pristera and Dr H. Walter, who had wide experience in analysis of polynitro derivs of toluene, phenol, etc. If the sample is a solid, its mp must be detd and if it is a liquid, its bp. Next comes the analysis by lR(if an apparatus is available). Experiments at PicArsn showed that IR spectrograms of various nitrated derivs of toluene permitted distinguishing, not only the degree of nitration but also the position of NOa groups (Refs 13 14). In later work spectrograms of o- and p-nitroanilines [See paper by F. Prist era et al published in Anal Chem 32, 497(1960)] showed distinct differences between these two compds. 

The stronger the acid concentration, the higher the degree of nitration and the larger is the yield. An excess of acids establishes equilibria that favour a more complete reaction. The surplus must not be too large, however, since nitroglycerine is slightly soluble in spent acid and this may considerably decrease the yield of... 

Nitrocellulose of 12.65% N, according to this nomenclature, is called 2i-nitrate, etc. The degree of nitration can also be designated by the degree of substitution (D.S.) which is the average number of nitrated hydroxyl groups in one anhydroglucose unit. 

The dimensions of a nitrocellulose crystal cell depend on the degree of nitration. Values from the papers of Mathieu [14, 34] characterizing native cellulose and various nitrocelluloses are quoted in Table 38. 

Lunge et al. [15] has examined the influence of the H2S04 HN03 ratio on the rate of reaction, confirming the earlier observations of Vieille that increasing the amount of sulphuric acid decreases the rate of the chemical reaction. Thus the maximum degree of nitration is reached ... 

Temperature coeffident of nitration. Experiments have shown that in a moderate range, e.g. from 0 to 45°C, temperature affects the degree of nitration very little. A decrease in temperature usually results in some decrease in degree of nitration on a technical scale, where nitration time is limited, but this is because equilibrium is not reached, and the rate of the reaction is the governing factor. From a knowledge of the heat of nitration it should be possible to predict the course of the reaction from the known equation ... 

In practice the H2S04 to HNOs ratio ranges from 2.5-3, while the water content should be varied according to the required degree of nitration, the solubility of nitrocellulose, etc. 

The properties are very sensitive to composition and the charge carriers are apparently positive. Other studies have shown poly(acenaph-thalene) to be only slightly photo-conductive while the nitrated polymer exhibits a photocurrent dependent upon the degree of nitration (100). Since the number of mobile n electrons is the same as in poly (vinyl naphthalene), the authors conclude that some form of stereoregularity is required for enhanced conductivity. Complexes of poly(vinyl anthracene) with halogen molecules show enhanced conductivity and reduced activation energy which is thought to be typical of an electronic semiconductor (101). 

The extent or degree of nitration of cellulose is expressed by the nitrogen content, except in France some ocher Latin countries, where the degree of nitration is expressed as cc s of NO evolved in a nitrometer and measured under std conditions, per lg of NC. Each O.lcc of NO corresponds to ca 0.0063%, °r each percent of NO times 15.96 equals number of cc of NO(Ref 44,p 258 Ref 50, table 3 Ref 51,p 367)... 

The mixed acid used in the nitration of cellulose has a compn dependent upon the type of cellulose nitrated, the degree of nitration desired, and the season of the year. During warm weather, it is necessary that the HN03 content be si greater than during winter, because of a tendency toward denitration of the mixed acid during warm weather. Variations in mixed... 

A flow sheet of Biazzi s process installed at the Canadian Industries Ltd Calgary plant is given by Pennie (Ref 48). It is reproduced here The Biazzi s process can be used not only for the manuf of NG, NGc DEGDN but also for manuf of aromatic and aliphatic nitrocompds. For mono-nitration, only one nitrator is required for each installation.. This includes MNB, MNT, Methyl nitrate, etc. For higher degrees of nitration of... 

An account of smokeless powder is, in its main outlines, an account of the various means which have been used to regulate the temperature and the rate of the burning of nitrocellulose. After the degree of nitration of the nitrocellulose, other factors which influence the character of the powder are the state of aggregation of the nitrocellulose, whether colloided or in shreds, the size and shape of the powder grains, and the nature of the materials other than nitrocellulose which enter into its composition. 

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