Ceramic grade CMC (carboxymethyl cellulose) is an important chemical widely used in the ceramic manufacturing process. As a natural polymer material, CMC is a derivative of cellulose, and its molecular structure contains multiple carboxymethyl (-CH2COOH) groups, which makes it water-soluble and has good adhesion. The role of ceramic grade CMC in the ceramic industry is mainly reflected in adhesives, dispersants, thickeners and stabilizers.

1. Properties and structure of CMC
CMC is obtained by carboxymethylation of natural cellulose. It has the following characteristics:

Water solubility: CMC can dissolve in water to form a solution with a certain viscosity.

Adhesion: The presence of carboxymethyl groups in its molecules enables it to enhance the bonding force between particles, thereby improving the strength and stability of ceramic products.

Adjustability: By adjusting the molecular weight and degree of carboxymethylation of CMC, its solubility, viscosity and other characteristics can be controlled to meet the needs of different ceramic production processes.

2. Application of CMC in ceramic production
Binder function: In the preparation of ceramic mud, CMC is often used as a binder. It can enhance the viscosity of the mud, making it easier to bond during the molding process, avoiding shedding and cracking, especially during the drying process, it can effectively prevent the cracks caused by too fast water loss in ceramic products.

Dispersant function: In the ceramic production process, raw materials such as clay, quartz, feldspar, etc. often need to maintain a certain degree of dispersion in water. CMC can effectively disperse these raw material particles and prevent them from settling in the aqueous solution, thereby ensuring the uniformity of the slurry and improving the quality of ceramic products.

Thickener function: After CMC is dissolved in water, it can significantly increase the viscosity of the solution. By adjusting the amount of CMC added, the rheological properties of the slurry can be accurately controlled, thereby optimizing the ceramic molding process. Increasing the viscosity can also make the slurry have better stability and operability during the molding process.

Stabilizer function: The stability of ceramic slurry is crucial to the molding quality. CMC can help the slurry maintain a stable pH value and viscosity, prevent the occurrence of problems such as stratification and precipitation, and thus ensure the uniformity and consistency of the product.

Function during firing: During the firing of ceramics, the decomposition products of CMC can serve as a source of organic matter to help the formation of ceramics during the firing process. It can also improve the smoothness and glossiness of the ceramic surface and improve the appearance quality of the finished product.

3. Characteristics of Ceramic Grade CMC
High purity: Ceramic grade CMC requires a higher purity to avoid impurities affecting the performance of ceramic products. High purity CMC can effectively reduce the generation of gas during firing and ensure the density and hardness of ceramics.

Uniform particle size: The particle size of ceramic grade CMC is required to be uniform, which helps its dispersibility and stability in ceramic slurry. CMC with finer particle size can provide better thickening and dispersion effects.

Good dispersibility and adhesion: Another key requirement for ceramic grade CMC is excellent dispersibility and adhesion, which directly affects the uniformity and molding quality of ceramic slurry.

Low ash content: The ash content in ceramic grade CMC needs to be controlled at a low level. Too high ash content will have a negative impact on the firing quality of ceramics and the strength and appearance of the final product.

4. Production process of ceramic-grade CMC
The production of ceramic-grade CMC is usually carried out through the following steps:

Raw material processing: Select high-quality natural cellulose as raw material, pre-treat it and remove impurities.

Carboxymethylation reaction: React cellulose with chloroacetic acid and perform carboxymethylation under alkaline conditions to generate CMC.

Neutralization and washing: The CMC solution after the reaction needs to go through neutralization, washing and other steps to remove residual alkaline substances and other impurities.

Drying and crushing: The treated CMC liquid is dried to form a powder. Finally, the required particle size specifications are achieved by crushing.

As a functional material, ceramic-grade CMC has multiple advantages and is widely used in many links in the ceramic manufacturing process. It can not only serve as a binder, dispersant, thickener and stabilizer, but also improve the quality and stability of ceramic products. With the development of the ceramic industry, the performance requirements for CMC are constantly increasing, and the production process and application fields of ceramic-grade CMC are also constantly developing and improving. Therefore, ceramic-grade CMC is undoubtedly one of the important materials in ceramic production, and it plays an important role in improving the quality of ceramic products.