Nitrocellulose, Compressed

The nitrocellulose is first dehydrated, that is the water present is replaced by alcohol. This is done by compressing the wet nitrocellulose in a hydraulic press and passing alcohol through the press until the strength in the block is about 92%. The resulting block of alchohol wet nitrocellulose is broken down to small pieces with toothed rolls. 

Hollings patented, in 1898 in England, the method of preparation of compressed charges of wet nitrocellulose in two stages first by. using a worm screw in a cylinder, provided with numerous small perforations, followed by hydraulic pressing. During the first operation air... 

Earlier observations that nitrocellulose burns very quickly in a confined space-much more quickly than blackpowder— were confirmed. Since it is difficult to reduce the burning rate by physical methods only, e.g. by compressing the nitrocellulose to increase its density, attempts were made to slow down the rate of burning by the addition of phlegmatizing substances, such as glues, waxes, fats etc. 

The nitrocellulose to be loaded into the centrifuge may be in lump form or compressed (taken directly from the transportation cases). To attain uniformity in the... 

After the cylinder has been loaded at position (/), the set of cylinders is turned through 90° so that cylinder (/) moves to position (2). Here the bottom of the cylinder is formed by a lower piston in which there are furrows and conduits to drain away alcohol and water. About 20 1. of 95-96% refined alcohol is now poured onto the layer of compressed nitrocellulose and forced through this layer by the upper piston at pressures of 50-100 kg/cm2. The water, dilute alcohol and finally less dilute alcohol flow out through the conduits in the lower piston. 

Brown also found that wet, compressed nitrocellulose could be... 

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 ... 

Cotton or wood pulp as delivered to nitrocellulose plants contains 6% or more of moisture. This moisture should be removed prior to nitration so that it does not bring about any dilution of the mixed acid and thereby change the course of the reaction. Cotton is usually transported in the form of compressed bales, which are opened and shredded before drying. Wood cellulose, in the form of pressed cellulose pulp or of crepe paper, is dealt with similarly. Dryers for dehydrating cotton or cellulose may be of various types. The simplest is the shelf drier, equipped with mechanical ventilation and heaters situated at the bottom, supplied with water or steam so as to maintain a temperature of 80-100°C inside the drier. 

The essential problem in the operation of kiering whether it takes place in autoclaves or in tubes, lies in the removal of add vapours evolved from the nitrocellulose as a result of the denitration of unstable cellulose esters. Vapours collected in the kiers are removed from time to time by opening a gas-release valve which allows the compressed gases to pass into a special duct. In the continuous boiling process in pipes, the gases are entrained with the suspended nitrocellulose. 

Compressed Nitrocellulose, Guncotton, molded into blocks of regular shape by means of high pressure, was formerly used for military pur-... 

A) Podryvnaya Shashka (Blasting Sword) or Piroksilinovaya Shaska (Guncotton Sword). A cartridge consisting of compressed 13% N Nitrocellulose, called in Rus Piroksilin, contg ca 18% moisture. It was made since 1890 in various sizes. Its use was discontinued after WWI in favor of Trotil (TNT) demolition charges... 

Hexamethylenetriperoxidediamine is almost insoluble in water and in the common organic solvents at room temperature. It detonates when struck a sharp blow, but, when ignited, bums with a flash like nitrocellulose. Taylor and Rinkenbach 63 found its true density (20°/20°) to be 1.57, its apparent density after being placed in a tube and tapped 0.66, and its density after being compressed in a detonator capsule under a pressure of 2500 pounds per square inch only 0.91. They found that it required a 3-cm. drop of a 2-kilogram weight to make it explode, but that fulminate required a drop of only 0.25 cm. In the sand test it pulverized 21/ to 3 times as much sand as mercury fulminate, and slightly more sand than lead azide. It is not dead-pressed by a pressure of 11,000 pounds per square inch. It is considerably... 

In 1864, Abel greatly improved the stability by alternately boiling and pulping the nitrocellulose he also tried to control the speed of combustion of the finished explosive by compressing it. In about 1884, Schultze introduced a partially colloided nitrocellulose in combination with metallic nitrates, and at about the same... 

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