Carboxymethyl cellulose

Other Name: CMC, carboxymethocel, cellulose glycolate

CAS number: 9000-11-7

EINECS number: 618-326-2

Appearance: White solid

Physical property: 

Carboxymethyl cellulose (CMC) is an anionic cellulose, the appearance is white or slightly yellow flocculent fiber powder or white powder, odorless, tasteless, non-toxic; Soluble in cold water or hot water, forming a transparent solution with a certain viscosity. The solution is neutral or slightly alkaline, insoluble in ethanol, isopropyl alcohol and other organic solvents, but soluble in ethanol solution with 60% water content. It is hygroscopic, stable to light and heat, viscosity decreases with the increase of temperature, the solution is stable at pH 2 ~ 10, the pH is lower than 2, there is solid precipitation, the pH value is higher than 10 and the viscosity decreases.

Chemical property: 

It is prepared from cellulose derivatives of carboxymethyl substituents, which are treated with sodium hydroxide to form alkali cellulose, and then reacted with monochloroacetic acid. The glucose unit that makes up cellulose has three replaceable hydroxyl groups, so products with different degrees of replacement can be obtained. When 1mmol carboxymethyl is introduced per 1g dry weight on average, it is insoluble in water and dilute acid, but can swell and be used for ion exchange chromatography. Carboxymethyl pKa, approximately 4 in pure water and 3.5 in 0.5mol/L NaCl, is a weakly acidic cation exchanger, usually used for the separation of neutral and basic proteins at pH > 4. When more than 40% hydroxyl group is carboxymethyl, it can dissolve in water to form a stable colloidal solution with high viscosity.

Main usage:

1, used in oil, natural gas drilling, digging and other projects

2, used in textile, printing and dyeing industry, the textile industry will CMC as a sizing agent, used for cotton, silk, chemical fiber, blended fabrics such as yarn sizing;

3, for the paper industry CMC in the paper industry can be used as paper smoothing agent, sizing agent.

4, CMC added to synthetic detergent can be used as dirt adsorbent; Daily chemical such as toothpaste industry CMC glycerol solution is used as the glue base of toothpaste; Used as thickener and emulsifier in pharmaceutical industry; CMC aqueous solution is used for flotation beneficiation after viscosification.

5, used in the ceramic industry. It can be used as blank adhesive, plasticizer, glaze suspension agent, fixing agent.

6, used in construction, improve water retention and strength

7, used in the food industry, the food industry uses high replacement degree CMC as ice cream, canned, quick cooking noodles thickener, beer foam stabilizer, in the processing of jam, sugar juice, sherbet, dessert, ice cream drinks, etc., as a thickener, binder or shape agent.

8, the pharmaceutical industry chooses appropriate viscosity CMC as the adhesive, disintegrator of tablets, suspension aid.