Nitrocellulose soluble

In Russia, Mendeleyev (Ref 12) worked out a method for the manufacture of smokeless powder from pyrocellulose, i.e. relatively high-nitrated (12.5% N) nitrocellulose soluble in a mixture of ether and alcohol. In 1892 the manu-... 

Nitrocellulose will dissolve in many solvents, e.g. acetone, acetic esters, ether-alcohol. There also exist types of nitrocellulose soluble in ethyl alcohol alone. 

Nitrogen content of original nitrocellulose Solubility, % Nitrogen content of fractions, % ... 

Like the lower alcohols, amyl alcohols are completely miscible with numerous organic solvents and are excellent solvents for nitrocellulose, resia lacquers, higher esters, and various natural and synthetic gums and resius. However, iu contrast to the lower alcohols, they are only slightly soluble iu water. Only 2-methyl-2-butanol exhibits significant water solubiUty. As associated Hquids, amyl alcohols form a2eotropes with water and//or a variety of organic compounds (Table 3). 

The problem of solvent selection is most difficult for high molecular-weight polymers such as thermoplastic acryHcs and nitrocellulose in lacquers. As molecular weight decreases, the range of solvents in which resins are soluble broadens. Even though solubihty parameters are inadequate for predicting ah. solubhities, they can be useful in performing computer calculations to determine possible solvent mixtures as replacements for a solvent mixture that is known to be satisfactory for a formulation. 

Dicyclohexylammonium nitrite s (DCHN) has a solubility of 3-9g in 100 g of aqueous solution at 25°C, giving a solution pH of about 6-8. Its vapour pressure at 25°C appears to be about 1-3 x 10 N/m but the value for commercial materials depends markedly on purity. It may attack lead, magnesium, copper and their alloys and may discolour some dyes and plastics. Cyclohexylammonium cyclohexyl carbamate (the reaction product of cyclohexylamine and carbon dioxide, usually described as cyclo-hexylamine carbonate or CHC)" is much more volatile than DCHN (vapour pressure 53 N/m at 25°C), and much more soluble in water (55 g in 100cm of solution at 25°C, giving a pH of 10-2). It may attack magnesium, copper, and their alloys, discolour plastics, and attack nitrocellulose and cork. It is said to protect cast iron better than DCHN, and to protect rather better in the presence of moderate concentrations of aggressive salts. 

Most of over six million dentures produced annually in the USA are made of acrylics (PMMAs) that includes full dentures, partial dentures, teeth, denture reliners, fillings and miscellaneous uses. Plastics have been edging into the dental market for over a half century. Even before the introduction of acrylics to the dental profession in 1937, nitrocellulose, phenol-formaldehyde and vinyl plastics were used as denture base materials. Results, however, were not wholly satisfactory because these plastics did not have the proper requisites of dental plastics. Since then, PMMAs have kept their lead as the most useful dental plastics, although many new plastics have appeared and are still being tested. Predominance of PMMAs is not surprising, for they are reasonably strong, have exceptional optical properties, low water absorption and solubility, and excellent dimensional stability. Most denture base materials, therefore, contain PMMA as the main ingredient. 

Shortly afterwards (1885) Vieille s powder was introduced in France under the name of B powder (Poudre B). Vieille utilized two types of nitrocellulose for its manufacture collodion cotton CP2, soluble in a mixture of ether and alcohol and forming the powder dough cotton CPi, insoluble in a mixture of ether and alcohol, incorporated into the powder mass in the form of unchanged fibres... 

These opposing tendencies may defeat the purpose of the fractional precipitation process. The fractional precipitation of crystalline polymers such as nitrocellulose, cellulose acetate, high-melting polyamides, and polyvinylidene chloride consequently is notoriously inefficient, unless conditions are so chosen as to avoid the separation of the polymer in semicrystalline form. Intermediate fractions removed in the course of fractional precipitation may even exceed in molecular weight those removed earlier. Separation by fractional extraction should be more appropriate for crystalline polymers inasmuch as both equilibrium solubility and rate of solution favor dissolution of the components of lowest molecular weight remaining in the sample. 

A breakthrough for tissue printing, at least for the botanical sciences, came when Cassab and Varner (3) combined the use of nitrocellulose and antibody technology. They placed sections of a freshly cut soybean seed on nitrocellulose membranes and probed the resulting imprints using specific antibodies. They were able to show that soluble extensin protein is primarily localized in the seed coat and vascular tissues. 

Pentaerythritol tetranitrate (PETN) is a colorless crystalline solid that is very sensitive to initiation by a primary explosive. It is a powerful secondary explosive that has a great shattering effect. It is used in commercial blasting caps, detonation cords, and boosters. PETN is not used in its pure form because it is too sensitive to friction and impact. It is usually mixed with plasticized nitrocellulose or with synthetic rubbers to form PBXs. The most common form of explosive composition containing PETN is Pentolite, a mixture of 20 to 50% PETN and TNT. PETN can be incorporated into gelatinous industrial explosives. The military has in most cases replaced PETN with RDX because RDX is more thermally stable and has a longer shelf life. PETN is insoluble in water, sparingly soluble in alcohol, ether, and benzene, and soluble in acetone and methyl acetate. 

Antibodies may also be used to determine the presence or identity of soluble antigens by a process known generally as immunoblotting. In a technique known as dot blotting , soluble antigens are applied to a nitrocellulose membrane in the form of dots , antibody is then applied to the membrane, the membrane is washed to remove unbound antibody, and the presence or absence of the antigen is determined by similar means to that employed during immunohistochemistry. 

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