Carboxymethylcellulose solubility

An interesting feature of current commercial products is that the polymer vehicles available for formulation have been limited to nonionic and anionic materials. The delivery vehicles available included off-the-shelf polymers such as carboxymethylcellulose, soluble starch, hydroxyethyl-cellulose, polyvinyl alcohol, poly(acrylic acid), and polyvinylpyrrolidone, or mixtures thereof. The choice of available polymeric delivery system primarily depends on component compatibility, aesthetics, and efficacy. However, by reliance upon available (off-the-shelf) systems, limitations on bioadhesion, drug bioavailability, contraceptive efficacy, and end-use characteristics has been limited. 

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. 

Methylcellulose and carboxymethylcellulose are forms of the familiar polysaccharide cellulose that have been treated to make them more soluble in water. Cellulose is a long chain made of the sugar glucose. The long chains mix with water to create a thick syrup or gel. 

Sodium carboxymethylcellulose (commonly known as CMC) was introduced in 1945 by Josephson and Dahle 10) for use in ice cream. It is cold water-soluble, will not react with acid, and has excellent water-binding properties. When properly processed, it is easily dispersible and quickly soluble in the mix. These properties make it well suited for high temperature-short time (HTST) mix. When used alone, it has a tendency to cause separation or wheying off in the mix. Irish moss extract is used with CMC to eliminate this condition. From 0.15 to 0.25% CMC is most often used in ice cream mix. 

Compared with wool and cotton, the scouring procedures for synthetic fibres are relatively simple since these fibres contain fewer impurities. Most of these have at least some degree of water solubility the most important are sizes and lubricants. The major sizes used are poly (vinyl alcohol), carboxymethylcellulose and poly (acrylic acid), all of which are completely or partially water-soluble. Sometimes aliphatic polyesters are used. 

The desizing of water-soluble size polymers can be summarised as follows. Batchwise or continuous methods can be used in both cases an adequate supply of hot water is needed during the washing-off. Hot water and detergent are needed to remove polyfvinyl alcohol) or carboxymethylcellulose. The addition of alkali may be beneficial with carboxymethylcellulose. Alkali is essential with modified starches and acrylic acid copolymers. Polyfvinyl alcohol) can be degraded effectively by alkaline oxidation. 

Clearly, one option to reduce the add-on is to use high-efficiency size formulations. However, there is a limit to what can be achieved by this approach. Even if the add-on is reduced to only 5%, the pollution load is still substantial. The two main options to facilitate disposal are (a) recovery of size polymers and (b) biological effluent treatment. Recovery of size polymers, particularly from water-soluble synthetic sizes, is based on extraction washing using the minimum quantity of water. Recovery rates in the region of 50% have been quoted for polyfvinyl alcohol) and carboxymethylcellulose size formulations. It is necessary to apply one of three concentration techniques precipitation, condensation or ultrafiltration [205]. 

Early soil-release agents, applied particularly to resin-finished cellulosic goods, were water-soluble polymers, many being related to thickeners (section 10.8) such as starch, hydroxypropyl starch, sodium carboxymethylcellulose, methylcellulose, hydroxyethyl-cellulose, alginates, poly(vinyl alcohol) and poly(vinylpyrrolidone). These functioned essentially as temporary barriers and preferential reservoirs for soil, which was thus easily removed along with the finish in subsequent washing, when they then helped to minimise... 

Water-soluble Carboxymethylcellulose (Cellulose Glycolic Acid). 293... 

CMC carboxymethylcellulose DADMAC polydiallyldimethylammoinum chloride C concentration of polymer (wt%) SOL soluble complex ... 

Unmodified and anionically modified starches, soluble cellulose derivatives such as carboxymethylcellulose, polyvinyl alcohol, latex and other polymers are also used in some specialised applications. Starch, however, because of its cost, is by far the most common dry strength additive, about twenty times more being used than, for example, polyacrylamide. 

Use carboxymethylcellulose only in small amount in unstructured liquid products, since it has low aqueous solubility. 

Sodium carboxymethylcellulose is formed by the reaction of sodium chloroacetate with basic cellulose solutions. The sodium form of carboxymethylcellulose is known as CMC or as a food grade product as cellulose gum. It is soluble in both hot and cold water. 

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. 

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. 

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... 

A homolog of carboxymethylcellulose, the carboxyethyl derivative, can be prepared by the condensation of such acrylic derivatives as acrylamide with alkali-cellulose.30 The homolog is water-soluble, and gives a clear, viscous solution. Proposed uses are similar to those mentioned for the carboxymethyl ether. 

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-... 

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... 

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