Carboxymethylcellulose , sodium salt

Prepare 500 mL of a 2% solution of carboxymethylcellulose, sodium salt, in water in the manner described in the U.S. Pharmacopeia reference above. Since the solution preparation is time-consuming, your instructor may prepare it ahead of time. Using a rotational viscometer with an appropriate spindle and a constant temperature bath, measure the viscosity of this solution at various temperatures. Plot viscosity vs. temperature. 

Part B Determination of the Concentration of Carboxymethylcellulose, Sodium Salt, in an Unknown... 

Carboxymethylcellulose Sodium Salt, poly(ediylene glycol), Poly(vinyl alcohol)... 

Starch derivatives Water-soluble cellulose derivatives Carboxymethylcellulose, sodium salt Hydioxyethylcellulose Hydroxypropylcellulose Hydroxypropylmethylcellulose Methylcellulose... 

Synonyms Carboxymethylcellulose Carboxymethylcellulose, sodium salt Carboxymethyl ether cellulose sodium salt Carmellose sodium Cellulose carboxymethyl ether... 

Figure 4 shows the of lyophilized formulations containing various polymer excipients as a function of relative humidity [26], As relative hymidity increased, for each formulation decreased. Formulations containing a, S-poly (vV-hydroxyethyl)-L-aspartamide (PHEA), methylcellu-lose (MC), and hydroxypropylmethylcellulose (HPMC) exhibited comparable r io values at lower humidities than formulations with dextran and carboxymethylcellulose sodium salt (CMC-Na). This indieates that the formulations containing PHEA, MC, and HPMC contain highly mobile protons at a lower temperature than the formulations containing dextran and CMC-Na at the same humidity. 

General methods for cross-linking of biopolymers such as hydroxyethylcellulose (HEC), carboxymethylcellulose sodium salt (CMC Na) and hyalnronic acid (HA) using water soluble carbodiamide are summarized in a review published in 2005 [24]. The interesting invention described the synthesis of water-insoluble derivative of hyaluronic acid cross-linked with biscarbodiimide [25]. 

Carboxymethylcellulose Sodium. Carboxymethyl ether of cellulose sodium salt (Citmcel) (8) is a white granular substance soluble in water depending on the degree of substitution. It is equally soluble in cold and hot water and may be prepared by treating alkaU cellulose with sodium chloroacetate. 

Carboxymethylcelluloses (CMC). CarboxymethylceUulose [9004 2-6] (CMC) is the carboxymethyl ether of cellulose. To prepare CMC, cellulose is steeped in sodium hydroxide solution, and the so-called alkaU cellulose is treated under controlled conditions with sodium monochloroacetate to form the sodium salt of CarboxymethylceUulose and sodium chloride. Therefore, the CMC of commerce is actuaUy sodium CarboxymethylceUulose... 

Polydimethyl-diallyl ammonium chloride is a strongly basic cation-active polymer. A mixture of polydimethyl-diallyl ammonium chloride and the sodium salt of carboxymethylcellulose, which is an anion-active polymer, is applied in an equimolar ratio [497] in aqueous sodium chloride solution. The proposed plugging composition has high efficiency within a wide pH range. 

Within this group, the linear polymers have been most intensively studied and researched. The main area of interest lies in water-soluble polymers. However, there have also been many studies into organic solutions, although there exist problems with odor and toxicity in the case of analytical studies. Among the water-soluble additives, tests were made especially on polyethyleneoxide (PEO), polyacrylamide and the coacrylates (PAAm, PAAm/AAcNa), polyacrylic add (PAA), guar gum (GG), carboxymethylcellulose (CMC) and sodium salts, as well as hydroxyethylcellulose (HEC). From these tests, PEO proved to be the most effective flow improver, followed closely by PAAm, which is somewhat more stable than PEO in turbulent flow. 

This substance, curiously, was referred to as cellulose glycolic acid in the earlier literature, though it might have been appropriately termed cellulose acetic acid. It is referred to herein as carboxymethylcellulose, although, in many cases, the sodium salt is actually the substance under discussion. This review summarizes the literature on the chemistry and uses of carboxymethylcellulose up to the present. 

Various salts other than the sodium salt have also received attention in this field. For example, lacquer films are prepared by the co-precipita-tion of a resin acid with aluminum carboxymethylcellulose,84 and the barium salt86 is said to possess thixotropic properties useful in paints. One unusual application involves the preparation of the water-soluble ferrous salt86 of carboxymethylcellulose which, when applied (for example to wall-... 

The USP 28 describes carboxymethylcellulose sodium as the sodium salt of a polycarboxymethyl ether of cellulose. Typical molecular weight is 90 000-700 000. 

Carboxymethylcellulose sodium is incompatible with strongly acidic solutions and with the soluble salts of iron and some other metals, such as aluminum, mercury, and zinc. Precipitation may occur at pH <2, and also when it is mixed with ethanol (95%). 

Tin-containing esters have also been synthesized by the reaction of the sodium salt of carboxymethylcellulose with tributyltin chloride. The reaction proceeds as follows ... 

Henningson CT. Karluk D, Ander P. Comparison of sodium ion interactions with sodium salts of carboxymethylcellulose and vinylic polyelectrolytes of varying charge density by diffusion. Macromolecules 1987 20 1286-1291. 

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