Nitrocellulose grades

Ma.nufa.cture. The batch nitration processes for nitrocellulose have included the pot process, the centrifugal process, the Thompson displacement process, and the mechanical dipper process. Semicontinuous nitration processes are also widely used for military and industrial grades. 

Acetophenone can react with formaldehyde to yield light-resistant resins which are used as additives in nitrocellulose paints. It is also used as a photoinitiator, and in the pharmaceuticals, perfumery, and pesticide industries (344). It can be hydrogenated to 1-phenylethanol which is used for the production of aromatic ester fragrances (345). Technical-grade acetophenone is available at 2.29/kg perfume-grade acetophenone was 6.50/kg in October 1994. 

Membrane filtration has been used in the laboratory for over a century. The earliest membranes were homogeneous stmctures of purified coUagen or 2ein. The first synthetic membranes were nitrocellulose (collodion) cast from ether in the 1850s. By the early 1900s, standard graded nitrocellulose membranes were commercially available (1). Their utihty was limited to laboratory research because of low transport rates and susceptibiUty to internal plugging. They did, however, serve a useflil role in the separation and purification of coUoids, proteins, blood sera, enzymes, toxins, bacteria, and vimses (2). 

Use of Sulfur-35 to Characterize the Sulfate Content in Nitrocellulose (NC). Military grades f NC are prepared by nitrating a suitable grade of cellulose, either cotton linters or wood pulp,... 

Alternate Method of Analysis. Grade A 4.4.3.3.1 Determination of RDX + Nitrocellulose. Weigh accurately a sample calculated to contain between 0.35 and 0.40g of TNT into a tared 100-ml beaker. Add 20ml of RDX saturated benzene to the beaker. The prepn of the RDX saturated benzene is described in 4.4.3.5.5. Cover beaker with a watch glass and place on a steam bath for 30 mins, swirl soln frequently. (An oscillating hot... 

Determination of Wax + Lecithin. The percentages of TNT, RDX plus Nitrocellulose, Ca chloride, and aluminum are added and their sum subtracted from 100 percent. The remainder is taken to be the percentage of wax plus lecithin 4.4.3.4 Method of Analysis. Grade B... 

High Grade Nitrocellulose. Same as Guncotton described under Cellulose and Derivatives in Vol 2, p C106-R... 

The first successful static firing of plastisol propellant took place late in 1950 as part of a broad program conducted by Atlantic Research Corp. to investigate and evaluate plastisol propellants and methods for their manufacture (16). Major attention was directed to poly (vinyl chloride), cellulose acetate, and nitrocellulose, although other polymers were tested for their suitability (17). Patent applications were filed for plastisol propellant compositions and manufacturing processes, based on poly(vinyl chloride) (PVC) (19) and on nitrocellulose (18). The commercial availability of dispersion grade PVC enabled work with this resin to advance rapidly. The balance of this paper is devoted to a discussion of PVC plastisol propellants and their manufacture. 

An essential, important test is the measurement of the viscosity of a cupram-monium solution of the cellulose, as by this method it is possible to classify cellulosic material into grades suitable for manufacturing lacquer nitrocellulose of the desired viscosity. 

Nitrocellulose of 11.8-12.3% N intended for celluloid manufacture is obtained in a way resembling the production of lacquer-grade material with the exception that the viscosity of the product is not of such decisive importance. Low viscosity of the nitrocellulose can cause the celluloid gel to be brittle, however. For this reason care should be taken to keep the viscosity above a certain limit. The essential stabilization can be carried out in boilers without recourse to autoclaves, but in order to shorten the stabilization process it is possible to carry out the kiering in autoclaves, the process then requiring only a few minutes. 

Recently interest was evinced in nitrocelluloses of very low nitration grade, e.g. 0.5-2.0% [4], They were obtained by nitrating cellulose with mixtures containing 32% HN03, 31-38% H2S04 and 32-37% H20 at 8-30°C. 

In 1855, the moldable features of collodion were exploited by the British inventor and chemist Alexander Parkes, who marketed the material as Parkesine. Combs, earrings, buttons, bracelets, billiard balls, and even false teeth were manufactured in his factories. Parkes chose to focus more on quantity than on quality, however. Because he used low-grade cotton and cheap but unsuitable solvents, many of his products lacked durability, which led to commercial failure. In 1870, John Hyatt, a young inventor from Albany, New York, discovered that collodions moldable properties were vastly improved by using camphor as a solvent. Hyatts brother Isaiah named this camphor-based nitrocellulose material celluloid. Because of its greater workability, celluloid became the plastic of choice for the manufacture of many household items. In addition, thin transparent films of celluloid made excellent supports for photosensitive emulsions, a boon to the photography industry and a first step in the development of motion pictures. 

For nitrocellulose, PVDF, and neutral nylon (e.g., Pall Biodyne A) 0.2% (w/v) casein (e.g., Hammarsten grade or I-Block Applied Biosystems) in TTBS (see recipe). 

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