Nitrated Polysaccharides

Explosives, examination of finisheblack powder, 29 dinitrobenzene, 47 dinit rocdil or hydrin, 41 dinitroglycol, 40 industnal blasting explosives, 54 lead azide, 60 mercury fiilminate, 59 nitrated polysaccharides, 42 nitrocellulose, 32 nitro-compounds (additional), 48 nitroglycerine, 39 nitromannite, 43 nitronaphthaienes, 47 picric acid and picrates, 44 smokeless powders, 49 starch nitrate, 41... 

Nitramine oXygen in tetryl, estimation of, 48 Nitrated inulin and lichenin, 42 Nitrated polysaccharides, 42 Nitre. See Potassium nitrate Nitric acid, for use in explosives, examination of, 14 Nitric esters, 32... 

Denitration can be effected by chemical reducing agents (134)- For monomolecular nitrates, reductive denitration with hydrogen and Raney nickel (135) is preferable. Ammonium hydrogen sulfide effectively denitrates the nitrated polysaccharides. 

Mannans (Tagut Nut, Corajo, Vegetable Ivory, Carobean), (CgHioOg, mw 162.14. Poly-, meric polysaccharides which yield mannose on hydrolysis. They can be acetylated and nitrated... 

Nitrogluoosides. Wrightsman patented the prepn of expls by the nitration of a methanol soln of glucosides, or a polyhydric ale soln of polysaccharides... 

Nitrostarch (NS) is a nitrate ester (more properly a mixt of several nitrate esters) of starch, which is a plant-product polysaccharide of the general formula (CgHujOj) The general molecular formula for NS is [C6H7(OH)x-(0NO2)y]n where x + y - 3, The following empirical relation, similar to that used for NC... 

Networks, polysaccharide, 24, 267-332 Neuberg, Carl, obituary of, 13, 1-7 Neuraminic acids, and related compounds, 13, 237-263 Nickel, Raney. See Raney nickel. Nitrates,... 

Dextrose Polymers and Their Nitrates. Dextrose (d-glucose) polymers can be obtd by heating dextrose or polysaccharides composed of dextrose units, in the presence of catalysts, such as boric anhydride, or boric acid. The resulting solid products are light in color and have a high 8 wide degree of... 

The most important of the carbohydrate esters of nitric acid are the polysaccharide nitrates, particularly cellulose nitrate or nitrocellulose (NC) and starch nitrate ( nitrostarch ) which is much less used. Nitric esters prepared from other sugars such as saccharose and lactose are not of any importance as explosives. 

The nitration of polysaccharides with nitrogen pentoxide in the gaseous phase has the advantage of not degrading the large molecule (Vollmert [73]). 

Studies on the white clover -Rhizobium trifolii interaction are the most advanced. Trifoliin A, a lectin present in clover-seedling roots, binds hapten reversibly to carbohydrate antigens cross-reactive on the capsular polysaccharide of R. trifolii and clover epidermal-cells.244 A specific hapten that inhibits binding of trifoliin A to both surfaces is 2-deoxy-D-arabino-hexose.245 It has also been shown that levels of trifoliin A on root hairs decline with increasing concentrations of nitrate, in parallel to root-nodule development,246 and that lectin receptors are transient on R. trifolii, in a way coinciding with its capacity to be adsorbed to clover roots.247... 

The use of nitrogen dioxide for the selective oxidation of polysaccharides to polyuronic acids was introduced by Kenyon and his coworkers13,63 in 1941. By this means extensive oxidation of the primary alcohol groups in cellulose was obtained, through the mechanism of preferential nitration followed by decomposition of the nitric acid ester with carboxyl forma-tion.68(0< > Apparently some undissociated nitration products also were formed, since infrared absorption studies54 indicated the presence of nitrate radicals in the polyuronic acid. Side reactions produced carboxyl,... 

An advantageous variant of the oxidation of polysaccharides by nitrogen oxides in 85% phosphoric acid consists in the use of sodium nitrate, instead of sodium nitrite, as the stoichiometric oxidant and a catalytic amount of sodium nitrite to decrease the induction time.123 The advantage of this variant may be seen by taking into account the stoichiometry of the overall reactions ... 

Clearly, two morphologically distinct mannans occur in ivory nuts, and, although both polysaccharides contain the same chemical features, there is evidence that they differ in molecular size. Thus, nitration of ivory-nut shavings followed by fractionation of the polysaccharide nitrates affords... 

Although most polysaccharides may be acylated without degradation, acyl derivatives of xylans29 are often unsatisfactory for molecular-weight determinations owing to their poor solubility characteristics. Mixed esters of xylans143 are often superior in this respect, but there are obvious difficulties in the differential analysis of acyl groups. Hemicellulose nitrates have been used for measurements of molecular size,168 but xylan nitrates,29 like xylan acetates, are reported to have poor solubility characteristics. 

Table 4. Effects of feeding of carbon and nitrogen sources on cell growth and the content (C), production (Pn) and productivity (Pv) of ginseng saponin and polysaccharide. The cell culture in a modified MS medium was taken as a control. Cases 1,2 and 3 Sucrose was fed beginning from day 15,18 and 20, while its level was kept below 20,10 and 20 gH, respectively. Cases 4,5 and 6 Feeding of 20 mM nitrate, 10 mM nitrate plus 10 mM ammonium, and 20 mM ammonium on day 15, respectively, where sugar addition was the same as in case 1...

The first probable values for the molecular size of the native pectins from apple and sugar beet were obtained by Schneider and co-workers.71 These workers prepared the nitro- and acetyl-derivatives in order to avoid the anomalous behavior due to charge effects which occurred using the unsubstituted polysaccharides. From osmotic and viscometric measurements on the nitrate, values for the molecular weight of 30,000-100,000 were found, the constant Km in Staudinger s equation being 6(10)-4. Viscometric measurements indicated that there was little difference in size between the two derivatives. 

Fractional precipitation or dissolution of polysaccharides (and polysaccharide acetates or nitrates), either by changing the solvent composition, pH, or temperature, is generally of only limited application, except for the removal of extraneous material, because of the tendency to coprecipitation and occlusion of other polysaccharides. As most polysaccharides show considerable polymolecularity (that is, they have a broad molecular-weight... 

Cellulose is the most abundant naturally oeeurring polysaccharide formed out of glucose-based repeat imits, connected by 1,4-beta-glucosidic linkages. Cellulose and its derivatives are widely used as tough versatile materials. Cellulose nitrate, cellulose acetate (CA) and cellulose xanthate (rayon) can be easily molded or drawn into fibers for textile applications, for designing composite materials (safety glass), as thermoplastics etc [80]. 

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