Nitrocellulose specific gravity

The specific gravity of semicoiloidal nitrocellulose powder with a mixture of ether and alcohol as a solvent usually ranges from 1.54-1.63, although the specific gravity of nitrocellulose itself is 1.66. This indicates a certain porosity of the powder. The pores are filled either with air or with traces of residual solvent. According to Brunswig [17] 100 g of nitrocellulose rifle flake powder contains 4-8 cm3 of the air. 

PETN differs from other nitric esters in failing to produce a colloid solution with nitrocellulose. This is the result of the symmetrical structure of PETN, which has a zero dipole moment. PETN is completely non-hygroscopic. Its specific gravity in crystalline form is 1.77. On compression the following density values are obtained ... 

Earlier authors Wehrhahn [23] and Mosenthal [24], assumed that the specific gravity of nitrocellulose determined in water is independent on the nitrogen content, and is 1.66. For cellulose in alcohol, Mosenthal reports the value 1.56-1.58. The specific gravity of nitrocelluloses of different nitration degree has been determined by Brunswig [25]. 

The determination of the specific gravity of nitrocellulose is beset with difficulty, since the result depends to a considerable extent upon the capacity of the liquid used for measurement to penetrate into the interior of the colloidal structure of the fibre. Petitpas and Mathieu [27] have estimated the specific gravity of trinitrocellulose ... 

Type of nitrocellulose Composition of the adds HNOj h2so4 h2o no2 Specific gravity (at 15°C)... 

The quantity of the high explosive of the true AC type tested depends naturally on its specific gravity, with the result that it ranged from 0.4 g for nitrocellulose, which is composed of gun cotton and collodion cotton, to 2.4 g for nitroglycerin in the case of high explosives of the true AC type tested herein. 

A value of for nitrocellulose powder (,13.4 % N) formed into a cylinder, U cm in diameter, 1.3 in specific gravity, and placed in the atmosphere under isothermal conditions... 

In this connection, as commented in a footnote given under Table 24 in Section 9.5, it has been reported by J. Isler that the critical temperature for the thermal explosion of nitrocellulose powder (13.4 % N) formed into a cylinder, 1,1 cm ill diameter, 1,3 in specific gravity, and placed in the atmosphere under isothermal, but open, conditions, is 145 "C [75], This temperature value, 145 C, is far higher than 76" 77 °C, i.e., the value of SADT calculated herein for guncotton or collodion cotton, having an arbitrary shape and an arbitrary size, confined in an arbitrary closed container of the corresponding shape and size, and placed in the atmosphere under isothermal conditions (refer to the superscript, given in Table 24). 

Structure of nitrocellulose Physical properties of nitrocellulose Melting points Specific gravity Solubility... 

The first five components are high speed dispersed or bead milled. The 1/2 Sec Nitrocellulose (80/20 Plasticiser) is predissolved in the solvents (toluene, acetone and ethyl acetate) before it is added to the above. The nitrocellulose could be replaced with a suitable grade of CAB. Mixed viscosity is 40-45 secs B4 at 20°C with a specific gravity (S.G.)of 1.16. 

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