Microcrystalline cellulose is an important natural high molecular weight compound, mainly composed of linear polysaccharides linked by β-1,4-glucosidic bonds. Using natural cellulose as a raw material, it is processed through methods such as dilute acid hydrolysis to form extremely fine short rod-shaped or powdery porous particles. This white, odorless, tasteless crystalline powder has a wide range of applications in the pharmaceutical, food, and cosmetic industries.

　　I. Properties and Structure

　　The particle size of microcrystalline cellulose is generally between 20 and 80 μm, and the limit degree of polymerization (LODP) is between 15 and 375. It is not fibrous, but it has excellent flowability, and it is insoluble in water, dilute acids, organic solvents, and oils, but it can partially dissolve and swell in dilute alkaline solutions. In addition, microcrystalline cellulose has high reactivity during carboxymethylation, acetylation, and esterification, which makes it possible for its application in multiple fields.

　　II. Application Fields

　　Pharmaceutical Industry: In the pharmaceutical industry, microcrystalline cellulose is used as an important excipient and is widely used in oral tablets and capsules. It can be used as a diluent, binder, disintegrant, and lubricant, improving the hardness and stability of tablets. At the same time, microcrystalline cellulose can also be used as a sustained-release agent for drugs, achieving slow release of active substances through its porous structure.

　　Food Industry: In the food industry, microcrystalline cellulose is used as an important functional food base material and health food additive. It can maintain the stability of emulsions and foams, improve stability during high-temperature processing, and can also be used as a non-nutritive filler and thickener to improve food structure. In addition, microcrystalline cellulose can also be used to control ice crystal growth, improving the taste and texture of frozen foods.

　　Cosmetics Industry: In cosmetics, microcrystalline cellulose is used as a filler, thickener, and emulsifier. It has good emulsification ability for oily substances and can improve the stability and dispersibility of cosmetics.

　　III. Market Prospects

　　With the expansion of the scale of production and the improvement of product grades in the leather, daily chemical, pharmaceutical, food, and chlor-alkali industries, the demand for microcrystalline cellulose has been increasing year by year. In China, the microcrystalline cellulose market has broad development prospects. At the same time, the foreign market also has a continuous demand for microcrystalline cellulose, especially in the United States and Europe, where microcrystalline cellulose has been widely used in food additives and pharmaceutical excipients.

　　IV. Preparation and Storage

　　The preparation of microcrystalline cellulose mainly uses the acid hydrolysis method. Natural cellulose is used as a raw material, and it is prepared through processes such as cellulose purification, acid hydrolysis, washing, drying, and pulverization. During storage, attention should be paid to maintaining a cool and dry environment and avoiding the influence of light, open flames, and high temperatures.

　　In summary, microcrystalline cellulose, as an important natural high molecular weight compound, plays an important role in many industries such as pharmaceuticals, food, and cosmetics. With the continuous growth of market demand and the continuous improvement of preparation technology, the application prospects of microcrystalline cellulose will be even broader.