Sodium carboxymethyl cellulose (CMC Na) whose CAS ：9004-32-4 is a carboxymethylated derivative of cellulose and the most important ionic cellulose adhesive. Sodium carboxymethylcellulose is a kind of anionic high molecular compound, whose molecular weight is from thousands to millions, which is usually produced by the reaction of natural cellulose with caustic soda and monochloroacetic acid. CMC Na is white fibrous or granular powder, odorless, tasteless, hygroscopic, easy to disperse in water to form transparent colloidal solution.
Carboxymethyl cellulose (CMC) is a kind of water-soluble cellulose ether, which is obtained by chemical modification of natural cellulose. Due to the poor water solubility of carboxymethylcellulose acid type structure, in order to better apply it, its products are generally made into sodium salt, with the molecular formula of [C6H7O2（OH）2OCH2COONa]n .
Classification of CMC:
According to the different uses, there are two kinds of products, alkaline and neutral. For industrial use, low viscosity (2% aqueous solution) is 0.2-0.5pa · s; for industrial use, medium viscosity (2% aqueous solution) is 0.3-0.6pa · s; for industrial use, high viscosity (2% aqueous solution) is 0.8-1.0pa · s.
Application of CMC
- Used in oil and gas drilling, well digging and other projects just like HEC
① The mud containing CMC can make the well wall form thin and hard filter cake with low permeability, and reduce the water loss.
② After adding CMC into the mud, the drilling machine can get low initial shear force, which makes the mud easy to release the gas wrapped in it, and at the same time, the debris can be quickly discarded in the mud pit.
③ Drilling mud, like other suspended dispersions, has a certain period of existence, which can be stabilized and extended by adding CMC.
④ Mud containing CMC is rarely affected by mold, so it is unnecessary to maintain high pH value and use preservatives.
⑤ CMC can be used as the treatment agent of drilling mud washing fluid, which can resist the pollution of various soluble salts.
⑥ The mud with CMC has good stability and can reduce water loss even when the temperature is above 150 ℃.
CMC with high viscosity and substitution degree is suitable for mud with low density, while CMC with low viscosity and high substitution degree is suitable for mud with high density. CMC should be selected according to mud type, area, well depth, and other different conditions.
- CMC is used as a sizing agent in textile, printing and dyeing industry, and it is used for sizing of cotton, silk, chemical fiber, blended and other strong fabrics;
- CMC used in the papermaking industry can be used as a paper smoothing agent and sizing agent in the papermaking industry. Adding 0.1% ～ 0.3% CMC to the pulp can increase the tensile strength of the paper by 40% ～ 50%, the compression rupture degree by 50%, and the kneading ability by 4 ～ 5 times.
- CMC can be used as dirt adsorbent when it is added into synthetic detergent; daily chemicals such as glycerin aqueous solution of CMC in toothpaste industry can be used as gum base of toothpaste; pharmaceutical industry can be used as thickener and emulsifier; CMC aqueous solution can be used as floating mineral processing after viscosity is increased.
- It can be used as an adhesive, plasticizer, suspending agent and fixing agent in the ceramic industry.
- For building, improve water retention and strength
7, for the food industry, the food industry uses a high degree of substitution CMC as ice cream, canned food, instant noodles thickener, foam stabilizer for beer, etc. in processing jam, syrup, fruit syrup, dim sum, ice cream drinks and so on as thickener, binder or agent.
- In the pharmaceutical industry, CMC with proper viscosity is selected as the binder, disintegrator of tablets and suspension aid of suspension.
The high-end substitute product of carboxymethylcellulose (CMC) is polyanionic cellulose (PAC), which is also an anionic cellulose ether, with a higher degree of substitution and uniformity of substitution, shorter molecular chain, and more stable molecular structure. Therefore, it has better salt resistance, acid resistance, calcium resistance, high-temperature resistance, and other properties, and its solubility is also enhanced. It can be applied to all industries of carboxymethylcellulose (CMC) to provide better stability and meet higher process requirements.