Additives carboxymethyl cellulose

Lead azide is not readily dead-pressed, ie, pressed to a point where it can no longer be initiated. However, this condition is somewhat dependent on the output of the mixture used to ignite the lead azide and the degree of confinement of the system. Because lead azide is a nonconductor, it may be mixed with flaked graphite to form a conductive mix for use in low energy electric detonators. A number of different types of lead azide have been prepared to improve its handling characteristics and performance and to decrease sensitivity. In addition to the dextrinated lead azide commonly used in the United States, service lead azide, which contains a minimum of 97% lead azide and no protective colloid, is used in the United Kingdom. Other varieties include colloidal lead azide (3—4 pm), poly(vinyl alcohol)-coated lead azide, and British RE) 1333 and RE) 1343 lead azide which is precipitated in the presence of carboxymethyl cellulose (88—92). 

Some part of the cellulose fraction is redirected to make cellulose derivatives, such as cellulose acetate, methyl and ethyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose. These derivatives find multiple applications, for instance, as additives in current products (e.g., paints, lacquers) of chemical industry. Typically, the preparation of cellulose derivatives takes place as a two-phase reaction cellulose is pretreated, for example, with alkali, and a reagent is added to get the substitution. Usually no catalyst is needed [5]. 

Y. T. Kalashnikov. Lubricant-sealer for profiled joints of casing pipes— contains soap plastic lubricant, polyacrylamide or carboxymethyl cellulose and additionally gypsum or cement powder, to increase sealing rate. Patent RU 2007438-C, 1994. 

V. S. Kotelnikov, S. N. Demochko, M. P. Melnik, and V. P. Mikitchak. Improving properties of drilling solution—by addition of ferrochrome-lignosulphonate and aqueous solution of cement and carboxymethyl cellulose. Patent SU 1730118-A, 1992. 

V. G. Mosienko, Y. I. Petrakov, A. M. Pedus, and V. N. Nikiforova. Complex additive to plugging solution—contains waste from production of sebacic acid, ammonium sulphate and carboxymethyl cellulose, reducing water separation, etc. Patent RU 2078908-C, 1997. 

Fluid loss additives such as solid particles and water-thickening polymers may be added to the drilling mud to reduce fluid loss from the well bore to the formation. Insoluble and partially soluble fluid loss additives include bentonite and other clays, starch from various sources, crushed walnut hulls, lignite treated with caustic or amines, resins of various types, gilsonite, benzoic acid flakes, and carefully sized particles of calcium borate, sodium borate, and mica. Soluble fluid loss additives include carboxymethyl cellulose (CMC), low molecular weight hydroxyethyl cellulose (HEC), carboxy-methYlhydroxyethyl cellulose (CMHEC), and sodium acrylate. A large number of water-soluble vinyl copolymers and terpolymers have been described as fluid loss additives for drilling and completion fluids in the patent literature. However, relatively few appear to be used in field operations. 

Carboxymethyl cellulose (CMC) is widely used as an additive to prepare drilling fluids and certain specialty fluids but failed to maintain acceptance in fracturing fluids because of its salt sensitivity and narrow temperature application range(131). 

Whey protein concentrates (WPC), which are relatively new forms of milk protein products available for emulsification uses, have also been studied (4,28,29). WPC products prepared by gel filtration, ultrafiltration, metaphosphate precipitation and carboxymethyl cellulose precipitation all exhibited inferior emulsification properties compared to caseinate, both in model systems and in a simulated whipped topping formulation (2. However, additional work is proceeding on this topic and it is expected that WPC will be found to be capable of providing reasonable functionality in the emulsification area, especially if proper processing conditions are followed to minimize protein denaturation during their production. Such adverse effects on the functionality of WPC are undoubtedly due to their Irreversible interaction during heating processes which impair their ability to dissociate and unfold at the emulsion interface in order to function as an emulsifier (22). 

The base readily penetrates the hair and promotes bleaching. The addition of stabilizers such as sodium pyrophosphate or sodium oxalate [16,17] retards the decomposition of hydrogen peroxide in the alkaline preparation and thus enhances the bleaching action. The same holds for complexing agents (seques-trants) such as ethylenediaminetetraacetic acid, which hinder decomposition due to traces of heavy metals. Thickening additives include carboxymethyl celluloses, xanthine derivatives, and synthetic polymers. Certain dyes can also be added. 

A convenient, laboratory preparation of sodium carboxymethyl-cellulose was carried out by McLaughlin and Herbst,11 in which they obtained products with a degree of substitution as high as 2.8 they studied the reaction with respect to such variables as elapsed time, temperature, and manner of addition of the reactants. 

The addition of carboxymethyl cellulose (CMC) and methyl cellulose (MC) to the nutrient solution (0.5-2.0 m/v %) effects a change of the fiber and network architecture [38] (Fig. 7). In the first case, the crystallization of the BC is affected by agglomeration of the CMC onto the fibers during self-assembly. The additive seems to compete with the BC for hydrogen-binding sites during ribbon construction [39] (Fig. 7a). In the second case, the adsorption takes place mainly on the planar ribbons (Fig. 7c). 

A direct relation between the polymer foams density (respectively, the expansion ratio) and the oligomer content in it has been established [114], Addition of water soluble polymers (polyvinyl alcohol, carboxymethyl cellulose, etc.) led to a reduction in resin consumption without deteriorating the quality of the solid foam obtained. Polymer foams of density 5-7 kg m3 were produced when the oligomer consumption was not more than 15-20% with respect to the solution volume. 

This process involves only one polymer (e.g., gelatin, polyvinyl alcohol, carboxymethyl cellulose), and the phase separation can be induced by conditions that result in desolvation (or dehydration) of the polymer phase. These conditions include addition of a water-miscible non-solvent, such as ethanol, acetone, dioxane, isopropanol, or propanol,addition of inorganic salts, such as sodium sulfate,and temperature change. ... 

Concentrated KOH aqueous solution (35-52%) is used for the electrolyte of the alkaline Zn/Mn02 cell. Certain amount of ZnO is usually added into the electrolyte to suppress gassing process.l " The electrolyte can be immobilized or gelled with addition of polymer materials, such as carboxymethyl cellulose. The major advantage of this electrolyte is that it has a high ionic conductivity, which helps improve battery rate... 

Figure 4-10. Schemetic diagram of events causing detergency [7], oriented soap molecules assumes a net negative charge similar to the globular micelle of soap. Cotton fibres also take up a negative charge when immersed in water. The electrostatic repulsions between the particles and the fibre play a major role in preventing redeposition. The addition of carboxymethyl cellulose (CMC) and/or polyvinyl pyrolidone (PVP) (Fig. 4-11) can act as anti-redeposition agents.

Thickeners and other additives In some cases a gel coating for the multiple emulsion drops may be beneficial, for example polymethacryhc acid or carboxymethyl cellulose. Gels in the outside continuous phase for a W/O/W multiple emulsion may be produced using xanthan gum (Keltrol or Rhodopol), Carbopol or alginates. 

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