Nitroglycerine viscosity

Nobel invented gelatinous dynamite in 1875 by accident. He investigated the effect of nitroglycerine on the collodion (nitrocellulose in a mixture of ether and alcohol) that he used to treat a cut finger and found that it produced a tough plastic material with adjustable viscosity and high water resistance. 

The nature of the nitrocellulose used is of particular importance in explosives if freedom from exudation of free nitroglycerine during storage is to be avoided. Nitroglycerine is only a poor solvent for nitrocellulose and stability of the gel depends on continuous formation and breakdown of gelled structures. The distribution of nitrogen content and viscosity, even in the individual fibres of the nitrocellulose, is therefore of paramount importance. 

The water content is varied to control the detonation velocity. For example a solution containing N2H5N03 70%, N2H4 7% and NH3 14% has a density of 1.31, detonation rate 8100 m/sec, fp -8°F and a viscosity of 12 cp. Variable amounts of perchlorates give impact sensitivities of 45-85 Kg/cm (nitroglycerin =... 

More in line with the predictive use of hazards analysis, however, is the experimental and theoretical assessment that the viscosity of the liquid significantly affects this mode of initiation. Such information allows redesign of the process to eliminate handling of low viscosity liquid explosives, and quantitative measurement of the sensitivity of the system to mild shocks as a function of viscosity may allow the optimum level to be selected. This is not necessarily a new concept, only quantified in a different manner. Thirty years ago transporters of neat nitroglycerine in the oil fields were paid 25 a day. The stipend for transporting jellied nitroglycerine was seven dollars, a practical comment on the understood difference in hazard. 

Plastic explosives, such as dynamites, are explosives rich in a liquid constituent, e.g. nitroglycerine, usually with dissolved high viscosity polymers. Guhr dynamite (no more in use) composed of 75% nitroglycerine and 25% kieselguhr, the first explosive to have a plastic consistency, owed this property to the high proportion of liquid it contained. 

On the basis of the dipole moment values and viscosity measurements of the two forms of nitroglycerine, de Kreuk [20] considered that the difference between the two forms is produced by rotational isomerism. According to this hypothesis the labile and stable forms would correspond to cis- and trans-isomers respectively. In a non-polar solvent the traits form predominates. In a polar solvent the content of the cis form increases and reaches a maximum in liquid nitroglycerine. 

The viscosity of nitroglycerine is higher than that of water but many times less than that of glycerine. The following results have been published by Naoum ... 

Collodion cotton is very readily dissolved in diethylene glycol dinitrate, more so than in nitroglycerine. The viscosity of diethylene glycol dinitrate at 20°C is 8.1 cP,... 

There exist instances where an increase in the viscosity of nitrocellulose solutions is recommended as in the product intended for manufacture of blasting gelatine, i.e. for the solution of nitrocellulose nitroglycerine. The solution must have the consistency of firm gelatine. 

DILUENT. (I) An ingredient used to reduce the concentration of an active material to achieve a desirable and beneficial effect. Examples are combination of diatomaceous earth with nitroglycerin to term the much less shock-sensitive dynamite addition of sand to cement mixes to improve workability with no serious loss of strength addition of an organic liquid having no solvent power to a paint or lacquer to reduce viscosity and achieve suitable application properties. 

The increase of viscosity of nitroglycerine by dissolving nitrocellulose reduce the ability of nitroglycerine to burn under turbulent conditions and reduces th critical diameter. The same author gave critical diameters of ... 

If the nitroglycerine it suspected to contain compounds such as dinitrochlorhydrin, it may be examined by specific gravity, nit en content, chlorine content, refractive index, Nitrosugan increase the viscosity and lower the nitrogen content. Hoffman and Hawse give a polarimetric method for nitrosugars. 

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