It is made by an alkaline catalytic reaction of cellulose with chloroacetic acid. Polar carboxyl groups make cellulose soluble and chemically effective. The functional properties of CMC depend on the degree of substitution of the cellulose structure (ie, the number of hydroxyl groups substituted in the substitution reaction), the length of the cellulose chain and the degree of assembly of the methylcarboxylate component.
CMC is used in foods and has the E number E466, where it is used as a viscosity modifier or thickener, and as a stabilizer for emulsifiers in various products such as ice cream. It is also an ingredient in many non-food products such as toothpastes, laxatives, diet pills, water-based paint, detergents, textile shredders, and the paper industry. It is mainly used because of its high viscosity, non-toxicity and hypoallergenicity. CMC is widely used in gluten-free and low-fat food products.
It is used in detergents as a polymer that helps disperse dirt and prevents it from reapplying to cotton or other cellulosic fabrics by creating a negatively charged barrier that prevents dirt from settling on the fibers. CMC is also used as a lubricant in artificial tears. MC is sometimes used, but the nonpolar methyl groups (-CH3) do not add any solubility or chemical reactivity to the basic cellulose.
This substance is used extensively in oral and topical pharmaceutical forms primarily as a viscosity-raising agent.
It is generally considered a non-toxic and non-irritating substance. But consuming large amounts of it may have a laxative and therapeutic effect.