Thermochemical and explosive properties of nitrostarch

Smolehski and Strzondala [41] determined the heat of combustion of nitro-starch of various nitrogen percentage and hence estimated the heat of formation of nitrostarch, for nitrostarch obtained both by nitration in mked acid (Table 106) or in nitric acid alone (Table 107). 

The dilferences in values between the two kinds of nitrostarch are regarded by the authors as related to the presence of sulphuric esters in the nitrostarches prepared by means of mixed acids. 

Nitrostarch when ignited burns readily in a way similar to nitrocellulose. 

Data characterizing the explosive properties of nitrostarch have been published by Hackel and T. Urbahski [42] for nitrogen contents from 7.7% to 13.4% N. 

Le Roux [42a] examined explosive properties of nitrostarch of 13.52% N. At a density of 0.90, a charge of 30 mm dia. in a cardboard tube detonated at the rate of 4970 m/sec. The relative lead block expansion was 117 (picric acid = 100), much the same as for nitrocellulose of 13.40% N. 

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