Glycerine trinitrate

Trimethylolnitromethane Trinitrate (Nitroisobutanetriol trinitrate, nitroisobutylglycerin trinitrate, nib-glycerin trinitrate)118... 

As shown by Hackel [144] glycerine trinitrate (nitroglycerine) does not form addition compounds with any of the aromatic nitro derivatives (mono-, di- or tri-nitro compounds). This is probably due to the inadequate number of nitro groups in nitroglycerine. 

Nitroglycerine with code of NG, also called glycerine trinitrate or propanetriol trinitrate, is the most widely used liquid explosive with strong explosion strength. 

Property and Preparation of Nitro Isobutyl Glycerine Trinitrate... 

Nitro isobutyl glycerine trinitrate with code of NB is also called trimethylol nitromethane trinitrate and nitro isobutanetriol trinitrate. 

Nitro isobutyl glycerine trinitrate is a light yellow sticky oily liquid. The industrial products are dark yellow because of the impurities in feedstock. Some products show abnormal brown or light green because of different production process. Molecular formula C4H6N4O11 Chemical stmcture ... 

Fig. 5.19 The volatilization loss of nitro isobutyl glycerine trinitrate with time at different temperature [5]...

Vapor pressure and volatility Less than nitroglycerine. Nitro isobutyl glycerine trinitrate is little volatile at room temperature without odor. It is slightly volatile at 30 °C with odor of tar and acridity. The volatility is increased at elevated temperature. It is obviously volatile at 50 °C. Its volatility at 25 °C is 0.127 x 10 mg/ cm/day. The relationship of the volatility of nitro isobutyl glycerine trinitrate and temperature is shown in Fig. 5.19 and its vapor pressures are listed in Table 5.49. 

The relationship between the surface tension of nitro isobutyl glycerine trinitrate and temperature is shown in Table 5.50. 

The freezing point of nitro isobutyl glycerine trinitrate is -35 °C and its viscosity is very large at 0 °C. At the temperature near the freezing point, it is like molten glass and can be drawn into a wire. Under the freezing point, it becomes hard wax with similar mechanical property of liquid phase. 

The solubility of nitro isobutyl glycerine trinitrate in water is less than that of nitroglycerine. Its solubility at 20 °C is 0.081 % and it is mutually soluble to diethyl ether, acetone, benzene, acetic ether, tetrachlormethane, dichlormethane, nitrobenzene, and nitrotoluene. Nitro isobutyl glycerine trinitrate can dissolve nitro aromatics. The property can be used to produce double-base propellants or multibase propellants. It is, to some extent, soluble to low nitrogenous cellulose nitrate (nitrogen content 11.8-12.2 %) for the production of double-base propellants. 

Nitro isobutyl glycerine trinitrate is soluble to concentrated sulfuric acid and dissociated to produce nitric acid. It is sensitive to react with bases as saponification reaction, especially for hydroxides of alkali metals and alkali-earth metals. Nitro isobutyl glycerine trinitrate can be destroyed by NaOH. In water or dilute acids, it is diflhcult to be hydrolyzed. However, in dilute base solution, it can be hydrolyzed to a yellow solution with a hydrolyzation constant of 1.81 x 10... 

Nitro isobutyl glycerine trinitrate is less thermally stable than nitroglycerine. It would be slowly decomposed during storage. The decomposition will be accelerated by acids, bases, water, and other impurities, or under heat treatment because of the self-catalyzed reaction of nitrogen oxide released in the decomposition process. 

It can be seen that the decomposition amount of nitro isobutyl glycerine trinitrate is four times larger than that of nitroglycerine after 5-6 h in the same decomposition conditions. 

The explosive decomposition of nitro isobutyl glycerine trinitrate to all gaseous products can be expressed as the following reaction equation ... 

Explosive grading Brisance compression height of nitro isobutyl glycerine trinitrate is listed in Table 5.51. 

It is different to prepare nitro isobutyl glycerine trinitrate from other nitrate esters. Two steps must be adopted in sulfuric acid predissolution method before nitration because the viscosity of isobutyl glycerine is high. Nitro isobutyl glycerine sulfate is first prepared and then nitrated to the nitrate ester by a mixed acid, as shown in the following mechanism. 

Those two steps are reversible reactions. Thus, the parameters in the reactions, such as concentrations of acids, amounts of acids, esterification temperature, would significantly influence the yield and purity of nitro isobutyl glycerine trinitrate. 

Fig. 5.22 Preparation process of nitro isobutyl glycerine trinitrate...

The theoretical yield based on the reaction equation is 189 %, but the actual yield is 163.5 %, about 86.5 % of the theoretical yield. The specification of nitro isobutyl glycerine trinitrate is summarized in Table 5.54. 

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