Application methods of carboxymethyl cellulose (CMC): professional discussion

Carboxymethyl cellulose (CMC) is an important water-soluble polymer compound. Due to its excellent physical and chemical properties, it has been widely used in various industrial fields. This article aims to systematically explain the application methods of CMC, analyze its specific applications in different industries in combination with its characteristics, and explore the profound impact of its application on process flow, product performance and environmental impact.

### 1. Basic characteristics of CMC and its application principles

CMC is an anionic polysaccharide polymer obtained by chemically modifying natural cellulose. Its main characteristics include good water solubility, thickening, film-forming, adhesion, suspension and stability, which determine the various applications of CMC in different industries. The application principle of CMC is based on its functional characteristics, which is usually achieved in the following ways: aqueous solution configuration, blending with other ingredients, physical or chemical cross-linking, etc.

### 2. Application of CMC in the food industry

#### 2.1 Thickener and stabilizer

In the food industry, CMC is widely used as a thickener and stabilizer. Its application method is usually to dissolve CMC directly in water to form an aqueous solution with a certain viscosity, and then add it to the food formula to control the rheology of the food. For example, in products such as ice cream, yogurt, and juice, CMC increases the viscosity of the system to prevent the sedimentation of solid particles and maintain the uniformity and stability of the product. In this process, the amount of CMC needs to be precisely controlled to avoid excessive thickening and poor taste.

#### 2.2 Water retaining agent

Another important application of CMC in foods such as meat products, bread and pastries is as a water retaining agent. Its application method is to dissolve CMC in water or other liquids during food processing and then evenly mix it into the food matrix. CMC effectively locks in moisture and prevents moisture loss by forming a three-dimensional network structure, thereby extending the shelf life of the product and improving the texture of the food.

### 3. Application of CMC in the pharmaceutical industry

#### 3.1 Binders in tablets and capsules

In the pharmaceutical industry, CMC is often used as a binder for tablets and capsules. Its application method is to mix CMC with drug powder and make tablets through wet granulation or dry tableting. The adhesive properties of CMC can enhance the mechanical strength of tablets and ensure that tablets are not easily broken during packaging, transportation and administration. In addition, the biocompatibility and non-toxicity of CMC make it an ideal excipient in drug preparation.

#### 3.2 Sustained-release materials in controlled-release preparations

CMC is also widely used in controlled-release preparations. As a sustained-release material, it can control the release rate of drugs. Usually, CMC is formed into sustained-release tablets or capsules by co-molding with drugs. In the body, CMC absorbs water and swells to form a gel layer, and the drug is slowly released by diffusion or dissolution. By adjusting the molecular weight and degree of substitution of CMC, the release curve of the drug can be precisely controlled to meet different therapeutic needs.

### 4. Application of CMC in daily chemical products

#### 4.1 Thickening and stabilization in detergents

In the field of daily chemical products, CMC is mainly used as a thickener and stabilizer in liquid detergents, shampoos and conditioners. Its application method is to dissolve CMC in the formula system under appropriate temperature and stirring conditions to form a uniform solution or emulsion. The thickening effect of CMC gives the detergent product a suitable fluidity and feel. At the same time, the stability of CMC can prevent the product from stratification or precipitation during storage, thereby increasing the shelf life of the product.

#### 4.2 Moisturizing and film-forming in skin care products

The application of CMC in skin care products is mainly reflected in its moisturizing and film-forming functions. Its application method is to dissolve CMC in the aqueous phase to prepare a viscous aqueous solution, and then mix it with other active ingredients, oils, etc. to form an emulsion, cream or gel product. CMC can form a breathable protective film on the skin surface to lock in moisture and prevent moisture evaporation, thereby improving the skin's moisture and smoothness. In addition, CMC's mildness and hypoallergenicity make it suitable for sensitive skin care products.

### 5. Application of CMC in the construction and ceramic industry

#### 5.1 As a thickener and water retainer for cement-based materials

In the construction industry, CMC is mainly used in cement-based materials such as mortar and concrete as a thickener and water retainer. Its application method is usually to mix CMC with cement, sand, water, etc. to form a uniform slurry. CMC improves the workability by increasing the viscosity of the slurry and prevents the material from flowing or stratifying during construction. At the same time, the water retention effect of CMC can delay the volatilization of water, ensure the full hydration of cement, and improve the strength and durability of the finished product.

#### 5.2 Additives for ceramic bodies and glazes

In the ceramic industry, CMC is widely used in the preparation of ceramic bodies and glazes. Its application method is to dissolve CMC in water and then mix it with ceramic raw materials or glaze components. CMC can improve the plasticity of the body and reduce cracking during the drying process. At the same time, in the glaze, CMC acts as a suspending agent and thickener to ensure the uniformity of the glaze and the glazing effect. During the firing process, CMC decomposes and volatilizes without leaving any residue, ensuring the purity and beauty of the ceramic products.

### 6. Application of CMC in the papermaking industry

#### 6.1 Paper strengthener and surface sizing agent

The application of CMC in the papermaking industry is mainly as a paper strengthener and surface sizing agent. The application method is to dissolve CMC in water and evenly distribute it in the pulp or apply it on the surface of the paper. CMC can improve the wet and dry strength of the paper, and enhance the folding resistance and tensile strength of the paper. In addition, the sizing effect of CMC can improve the surface smoothness and water resistance of the paper and improve the printing effect.

#### 6.2 Dispersants and rheology control agents in coated paper

In the production of high-grade coated paper, CMC is used as a dispersant and rheology control agent in the preparation of coating liquid. Its application method is to dissolve CMC in water, prepare a coating liquid, and then evenly apply it on the surface of paper. The dispersing effect of CMC ensures the uniform distribution of pigment particles in the coating liquid, preventing precipitation and flocculation. At the same time, the rheological control effect of CMC makes the coating liquid have good fluidity and coating properties, ensuring that the surface of the paper is smooth and flat.

### 7. Application of CMC in environmental protection and water treatment

#### 7.1 Flocculant in sewage treatment

One of the important applications of CMC in environmental protection is as a flocculant for sewage treatment. Its application method is to dissolve CMC in water and then add it to sewage. CMC combines with suspended particles to form floccules, promotes solid-liquid separation, and improves the efficiency of sewage treatment. CMC's good water solubility and biodegradability make it have a high environmental value in sewage treatment.

#### 7.2 Soil conditioner and soil and water conservation agent

In agriculture and environmental protection, CMC is also used as a soil conditioner and soil and water conservation agent. The application method is to mix CMC with soil, or dissolve it in water and spray it on the soil surface. CMC prevents soil erosion and water loss by increasing the water retention and aggregate structure of the soil, and promotes the growth and development of plants. This application is of great significance in desertification prevention and control and sustainable agricultural development.

### 8. Application prospects of CMC in emerging fields

With the advancement of technology and changes in market demand, CMC has broad application prospects in emerging fields. For example, in the field of biomedicine, the potential of CMC as a drug carrier and controlled release material is being deeply explored; in green and environmentally friendly materials, the degradability and low toxicity of CMC make it an important choice for sustainable materials. In addition, with the development of 3D printing technology, the application of CMC in printing materials will gradually expand, promoting the intelligent and personalized process of manufacturing.

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