Etherification synthesis principle of hydroxypropyl methyl cellulose (HPMC)

Hydroxypropyl methyl cellulose ((HPMC), the raw material cellulose, can be refined cotton or wood pulp. It is necessary to crush it before or during the alkalization process. The crushing is done by mechanical energy. Destroy the aggregated structure of cellulose raw materials to reduce crystallinity and degree of polymerization, increase its surface area, thereby improving the accessibility and chemical reaction ability of the reagents to the three hydroxyl groups on the cellulose macromolecular glucose ring base.

Hydroxypropyl methyl cellulose (HPMC) is used as the raw material substrate to produce oil, which can realize the utilization of whole sugar, improve the utilization rate of raw materials, reduce the residual amount of substrate in the fermentation broth, and reduce the cost of wastewater treatment. The characteristics of methyl cellulose facilitate the optimization of batch, fed-batch and continuous fermentation processes, avoiding a series of problems such as controlling the medium composition and dilution rate; at the same time, it is also conducive to the regulation of the fermentation process. Because the properties of hydroxypropyl methyl cellulose (HPMC) are similar to other water-soluble ethers, it can be used as a film-forming agent, thickener, emulsifier and stabilizer in latex coatings and water-soluble resin coating components, so that The film has good abrasion resistance, leveling and adhesion, and has improved surface tension, stability to acid and alkali, and compatibility with metallic pigments.

Hydroxypropyl methylcellulose (HPMC) has a good effect as a thickener for white water-based polyvinyl acetate paint. The degree of substitution of cellulose ether is increased, and the resistance to bacteria and erosion is also enhanced.

Although the principle of the etherification synthesis of hydroxypropyl methylcellulose (HPMC) is not complicated, it is alkalization, raw material crushing, and alkalization. The various environments of etherification, solvent recovery, centrifugal separation, washing and drying involve a large number of key technologies and rich knowledge.

For different types of products, each environment has the latest control conditions, such as temperature, time, pressure and material flow control. Auxiliary equipment and control instruments are a reliable and beneficial guarantee for stable product quality and reliable production system.

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