Carboxymethyl cellulose, applications

See also Carboxymethyl celluloses applications, 5 452t in paper manufacture, 18 115 physical properties, 5 450t production from chloroacetic acid,... 

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]. 

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). 

Cellulose disintegrants have been studied as insoluble matrices for sustained release tablets. Anionically charged carboxymethyl cellulose (sodium salt) was found to be inferior to methyl cellulose and poly(vinyl pyrollidone) as a binding agent for oxyphenbutazone tablets [291], However sodium carboxymethyl cellulose has found application as a dispersing agent for ibuprofen microspheres... 

Application and Principle This assay is based on the enzymatic hydrolysis of the interior (3-1,4-glucosidic bonds of a defined carboxymethyl cellulose substrate at pH 4.5 and at 40°. The corresponding reduction in substrate viscosity is determined with a calibrated viscometer. 

This equation suggests that the above discussion is reasonable. That is, application of Eisenberg s theory is valid for carboxymethylated wood containing metal ions. Accordingly, the mobility of carboxymethylate cellulose in carboxymethylated wood appears to depend on three factors electric charge, amount, and radius. The relationship is represented by Eq. (8). This result shows that Eisenberg s theory is valid for chemically modified wood containing metal ions. 

Cellulose can be esterifled with almost any organic acid [81,82,84], Whereas this is possible in principle with both alkyl chlorides and carboxylic anhydrides, commercial practice has focused on the anhydride option. Although many esters have been described in the literature, industrially manufactured organic esters are prepared only with aliphatic fatty acids with between 2 and 4 carbon atoms in length (i. e., acetates to butyrates, CA to CB). Exceptions are some mixed esters with phthalic acid, which are used for enteric coatings in pharmaceutical applications and a novel carboxymethyl cellulose acetate butyrate (CMCAB), which is used in water-borne coatings applications [81,84],... 

Industrial applications include anion-exchangers diethylaminoethyl cellulose (DEAE-cellulose) and the cation-exchanger carboxymethyl cellulose (CM-cellulose)... 

By use of a modification of the well-known Williamson synthesis it is possible to prepare a number of cellulose ethers. Of these materials ethyl cellulose has found a small limited application as a moulding material and somewhat greater use for surface coatings. The now obsolete benzyl cellulose was used prior to World War II as a moulding material whilst methyl cellulose, hyroxyethyl cellulose and sodium carboxymethyl cellulose are useful water-soluble polymers. 

Sodium carboxymethyl cellulose (CMC, cellulose gum) is an anionic, water-soluble polymer (Figure 5.13). It is stable in a pH range of 4 to 10 and is compatible with most monovalent and divalent salts, as well as most anionic and nonionic materials. However, it is generally incompatible with cationic species due to its anionic nature. The structural stability of dispersions induced by CMC is highly dependent upon the concentration of the polymer. CMC is used as a thickener in toothpastes, skin creams, lotions, and food applications. The degree of... 

Sodium carboxymethyl cellulose is an anionic water-soluble polymer and is widely used in oral and topical pharmaceutical formulations because of its viscosity-increasing properties. Viscous aqueous solutions are used to suspend powders intended for topical, oral, or parenteral applications [13]. It is also used as a tablet binder and to stabilize emulsions [14]. 

Of cellulose ethers only ethyl cellulose has found application as a molding material. Methyl cellulose, hydroxyethyl cellulose, and sodium carboxymethyl cellulose are usefiil water-soluble polymers. The first step in the manufacture of each of these materials is the preparation of alkali cellulose (soda cellulose) by treating cellulose with concentrated sodium hydroxide. Ethyl cellulose is made by reacting alkali cellulose... 

Mlshra, S., Rani, G. U., and Sen, G. (2012). Microwave initiated synthesis and application of pol3 crylic acid grafted carboxymethyl cellulose, Carbohydr. Polym.. 87,2255-2262. 

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