redispersible latex powder RDP for tile adhesivesDecember 7th 2023
hpmc manufacturer-Cellulose Ether Classification Hydroxyethyl Cellulose and Hydroxypropyl Methyl Cellulose
Cellulose ethers are classified according to the different etherification agents used. Hydroxypropyl methyl cellulose, methyl cellulose, carboxymethyl cellulose, ethyl cellulose, hydroxyethyl cellulose, benzyl cyanoethyl cellulose cellulose, carboxymethyl hydroxyethyl cellulose, etc.
Hydroxypropyl methylcellulose and hydroxyethyl cellulose are more practical.
The solubility of cellulose after etherification has changed significantly, and it can be dissolved in water, dilute acid, and dilute alkali. The solubility depends on three factors: (1) the characteristics of the groups introduced in the etherification process, the introduced groups The larger the value, the lower the solubility, the stronger the polarity of the introduced group, and the easier the cellulose ether is to dissolve in water; (2) The degree of substitution and the distribution of etherified groups in macromolecules. Most cellulose ethers can only be dissolved in water under the condition of substitution degree, and the substitution degree is between 0 and 3; (3) the degree of polymerization of cellulose ether, the higher the degree of polymerization, the less soluble; the lower the degree of polymerization, The wider the range of degrees of substitution that can be dissolved in water. There are many kinds of cellulose ethers, which are widely used in construction, cement, petroleum, food, textile, detergent, paint, medicine, papermaking and electronic components and other industries.
Cellulose hydroxyalkyl ethers are typically hydroxyethyl cellulose and hydroxypropyl cellulose. Etherifying agents are epoxides such as ethylene oxide and propylene oxide. Use acid or base as catalyst. Industrial production is to react alkali cellulose with etherification agent:
High substitution value hydroxyethylcellulose is soluble in both cold and hot water. Hydroxypropyl cellulose with high substitution value is only soluble in cold water but not in hot water. Hydroxyethyl cellulose can be used as a thickener for latex coatings, textile printing and dyeing pastes, paper sizing materials,
Architectural grade latex paint, architectural grade real stone paint, adhesives and maintenance colloids, etc. The use of hydroxypropyl cellulose is similar to that of hydroxyethyl cellulose. Hydroxypropyl cellulose with low substitution value can be used as a construction-grade thickener, which can have both functions of adhesion and water retention.