Carboxymethylcellulose CMC

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... 

Some of the exchanged resins were coated with cellulose acetate butyrate or cellulose acetate phthalate. The results showed relaxation rate enhancement in 25% water suspensions containing 2% carboxymethylcellulose (CMC) as a surfactant. The relaxivities, however, were rather low. It should be noted, however, that the measurements were made at high field, 300 MHz, where the relaxivity enhancements are always smaller. 

Cellulose may be converted from a water-insoluble polymer to a water-soluble polymer by the partial etherification of some of the hydroxyl groups by dimethyl sulfate. When the degree of substitution (DS) is 1.5 to 2.0, the hydrogen bonds are sufficiently weakened, and the methylcellulose is soluble in water. Carboxymethyl ethers, such as carboxymethylcellulose (CMC), are also water-soluble. The degree of solubility is related to the DS of the polymer and the pH of the solvent. 

Little has been known about ICD of dyes bound to polysaccharides. Nishida and Iwasaki 237 first found that AO molecules bound to carboxymethylcellulose (CMC) in aqueous solution exhibits ICD bands in its absorption region. The CD signs, positive at 425 nm and negative at 450 nm, were assigned to a left-handed configuration of the bound AO molecules. Hyaluronic acid also was analyzed in terms of the ICD of AO bound to it 238). In these cases, the helical handness of the polysaccharides had not been well defined. 

Composi ti on % wt Britesil H20 20 0 STPP 26.0 Sodium Carbonate 28.0 Nonylphenoxy Polyethoxyethanol, 9-10 Moles EO 10.0 Sodium Sulfate 10.0 Carboxymethylcellulose (CMC) 2 0 Sodium Alkylaryl Sulfonate Powder (90%) 4.0... 

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. 

The only sources of NSP in soft drinks are fruit materials, gums and stabilisers such as sodium carboxymethylcellulose (CMC) and pectins. Of these items, only fruit juices are used in significant quantities. The NSP content of most fruits falls within the range 0.9-3.6% w/w but, as Table 13.4 shows, very little remains in processed juices. Citrus comminutes are conventionally considered to have the same NSP content as the corresponding fruit but if they are known to contain substantial amounts of peel extracts this should be accounted for in calculations. 

Different water-soluble cellulose derivatives have been used for the determination of endocellulase activities. Carboxymethylcellulose (CMC) has been proposed as substrate and recently Almin et al. (3) have improved their method for the calculation of endocellulase activities, using a medium-molecular-weight CMC (Mv = 299,000 and Mw = 142,000) with well-defined physicochemical properties. No corrections... 

Figure 11. Antiinflammatory effect of (R)a-methylhistamine (MHA, 10 mg/Kg) and of ibuprofen (IBU, 30 mg/Kg), administered intragastrically in carboxymethylcellulose (CMC, 1%) 5 min before 1% carrageenin. The effect was measured 4 h later. On the ordinate % increase swelling. Mean values SEM from 10 rats. = P<0.05 vs control (Co, CMC alone).

Fig. 7. 55.2. Dimension change as a function of temperature for 30% sucrose solution during freezing at 5 °C/min down to -80 °C. 1, Fructose alone 2, fructose plus 0.25% sodium carboxymethylcellulose (CMC) (from [1.124])...

It is endocellulase-like in that it can hydrolyze and reduce the viscosity of carboxymethylcellulose (CMC), and it is exocellulase-like in that it produces mostly soluble oligosaccharides (87%) from insoluble cellulose... 

The power characteristic for viscoelastic fluids (Reher, 1969 Schiimmer, 1970) can also be described accurately by a relationship of the type Ne (Re ). Additional parameters to account for viscoelastic properties are needed only when the ratio of tangential to normal stresses is less than two (Reher, 1969). Power characteristics for the turbine stirrer in aerated non-Newtonian fluids (carboxymethylcellulose [CMC] and polyacrylamide [PAA] solutions) have been presented by Hocker and Langer (1962). 

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