Preparation of Sodium Carboxymethylcellulose

Safety precautions More this experiment is carried out. Sect. 2.2.5. must be read as well as the material safety data sheets (MSDS) for all chemicals and products used. 

---

Ion exchangers can also be made from cellulose, especially for scientific applications. They are prepared from alkali cellulose by reaction, for example, with chloroacetic acid (for preparation of sodium carboxymethylcellulose, see Example 5-6). By conversion with 2-chloroethyldiethylamine one obtains so-called DEAE-cellulose, an anion exchanger carrying 2-diethylaminoethyl groups, -C2H4N(C2H5)2. 

Aluminum salts have been prepared for use as adhesives31 or in sizing,32 by adding aluminum sulfate or alum to a solution of sodium carboxymethylcellulose while controlling the pH. Other metallic salts have received attention in relation to analytical procedures, and are discussed in this connection in Section IV. 

Various salts reportedly form adhesives suitable for paper-hanging,102103 and these may also be employed in the manufacture of sandpaper.104 Alkaline salts of inorganic, polybasic acids apparently enhance the adhesive qualities106 of sodium carboxymethylcellulose. A large number of different, adhesive preparations containing carboxymethylcellulose were manufactured by the Germans during World War II.106... 

Ma JH, Xu YJ, Fan B, Liang BR (2007) Preparation and characterization of sodium carboxymethylcellulose/poly(A-isopropylacrylamide)/clay semi-IPN nanocomposite hydrogels. Eur Polym J 43 2221-2228... 

Avicel RC and CL are water-dispersible, colloidal, microcrystalline cellulose products made for use in liquid preparations. Avicel RC and CL are coprocessed mixtures of microcrystalline cellulose and sodium carboxymethylcellulose. The amount of NaCMC can be determined using the IC method. About 10 g of Nasonex and about 25 mg of NaCMC NF are separately refluxed with 30 mL of glacial acetic acid for 2 h. The refluxed mixture is transferred to a 100-mL volumetric flask and diluted to volume with purified water, and mixed. The ion chromatograph (IC) was equipped with a suppressed conductivity detector, a 4-mm CSRS suppressor, current at 50 mA, a 250 mm x 4-mm Ion CS 12A column and a 50 mm x 4 mm Ion CG 12A guard column. The mobile phase is 0.13% methanesulfonic acid in water with a flow rate of 1 mL/min. Equal... 

Carboxym ethylcelluloses (CMC). Carboxymethylcellulose [9004-42-6] (CMC) is the carboxymethyl ether of cellulose. To prepare CMC, cellulose is steeped in sodium hydroxide solution, and the so-called alkali cellulose is treated under controlled conditions with sodium monochloroacetate to form the sodium salt of carboxymethylcellulose and sodium chloride. Therefore, the CMC of commerce is actually sodium carboxymethylcellulose... 

While for the complexation with poly(sodium styrene sulfonate) or sodium cellulosesulfate 1 1 stoichiometry has been reported [150] a non-stoichiometric complex results with sodium carboxymethylcellulose [150]. Optimized conditions make it possible to create membranes with various properties using the PDADMAC/sodium cellulosesulfate system [166-168]. However, the symplex formation with PDADMAC or copolymers mostly results in flocculated precipitates [27,150,169]. Highly ordered mulilayer assemblies were prepared by alternate reaction of PDADMAC and various polyanions [170,171]. Recently, the efficiency and selectictivity of protein separation via PEL coacervation were examined using PDADMAC [172]. 

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-... 

Sodium carboxymethylcellulose (CMC) is the most widely used water-soluble derivative of cellulose. It is prepared from alkali cellulose with sodium chloroacetate as reagent ... 

Spherical pellets containing 5% triamcinolone acet-onide were prepared by Villar-Lopez and coworkers byextrusion/spheronization after formulation with microcrystalline cellulose and/or a hydrophilic excipient such as lactose, sodium carboxymethylcellulose, or p-cyclodextrin. Their suitability for coating, with a view toward colonic drug delivery, was assessed in terms of their size, sphericity, and dissolution test... 

Sodium carboxymethylcellulose was analyzed by HPAEC-PAD for the purpose of quality control (Kragten, Kamerling, and Vliegenthart, 1992). This analyte is important in the food and coating industry. The samples were prepared by hot acid hydrolysis. Because the HPAEC-PAD method is direct, it has advantages over existing methods which require derivatization. 

Glass microslides (7.5 x 2.5 cm, thickness 0.2-0.4 mm) were prepared using a slurry obtained by mixing 2 g jS-CD-bonded silica gel with 6 ml aqueous solution of 0.3% sodium carboxymethylcellulose as binder. 

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. 

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. 

Carboxymethylcellulose sodium may be sterilized in the dry state by maintaining it at a temperature of 160°C for 1 hour. However, this process results in a significant decrease in viscosity and some deterioration in the properties of solutions prepared from the sterilized material. 

Alkali cellulose is prepared by steeping cellulose obtained from wood pulp or cotton fibers in sodium hydroxide solution. The alkaline cellulose is then reacted with sodium monochloro-acetate to produce carboxymethylcellulose sodium. Sodium chloride and sodium glycolate are obtained as by-products of this etherification. 

---