1. What is the alias of hydroxypropyl methylcellulose?
——Answer: Hydroxypropyl Methyl Cellulose, English: Hydroxypropyl Methyl Cellulose Abbreviation: HPMC or MHPC Alias: Hypromellose; Cellulose Hydroxypropyl Methyl Ether; Hypromellose, Cellulose, 2-hydroxypropylmethyl Cellulose ether. Cellulose hydroxypropyl methyl ether Hyprolose.
2. What is the main application of hydroxypropyl methylcellulose (HPMC)?
——Answer: HPMC is widely used in construction materials, coatings, synthetic resins, ceramics, medicine, food, textiles, agriculture, cosmetics, tobacco and other industries. HPMC can be divided into construction grade, food grade and pharmaceutical grade according to the purpose. At present, most of the domestic products are construction grade. In construction grade, putty powder is used in a large amount, about 90% is used for putty powder, and the rest is used for cement mortar and glue.
3. There are several types of hydroxypropyl methylcellulose (HPMC), and what are the differences in their uses?
——Answer: HPMC can be divided into instant type and hot-dissolution type. Instant type products disperse quickly in cold water and disappear into the water. At this time, the liquid has no viscosity because HPMC is only dispersed in water without real dissolution. About 2 minutes, the viscosity of the liquid gradually increases, forming a transparent viscous colloid. Hot-melt products, when met with cold water, can disperse quickly in hot water and disappear in hot water. When the temperature drops to a certain temperature, the viscosity will slowly appear until it forms a transparent viscous colloid. The hot-melt type can only be used in putty powder and mortar. In liquid glue and paint, there will be grouping phenomenon and cannot be used. The instant type has a wider range of applications. It can be used in putty powder and mortar, as well as liquid glue and paint, without any contraindications.
4. How to choose a suitable hydroxypropyl methylcellulose (HPMC) for different purposes?
——Answer::Application of putty powder: The requirements are relatively low, and the viscosity is 100,000, which is enough. The important thing is to keep water well. Application of mortar: higher requirements, high viscosity, 150,000 is better. Application of glue: instant products with high viscosity are required.
5. What should be paid attention to in the actual application of the relationship between the viscosity and temperature of HPMC?
——Answer: The viscosity of HPMC is inversely proportional to the temperature, that is to say, the viscosity increases as the temperature decreases. The viscosity of a product we usually refer to refers to the test result of its 2% aqueous solution at a temperature of 20 degrees Celsius.
In practical applications, it should be noted that in areas with large temperature differences between summer and winter, it is recommended to use a relatively low viscosity in winter, which is more conducive to construction. Otherwise, when the temperature is low, the viscosity of the cellulose will increase, and the hand feel will be heavy when scraping.
Medium viscosity: 75000-100000 mainly used for putty
Reason: good water retention
High viscosity: 150000-200000 Mainly used for polystyrene particle thermal insulation mortar rubber powder and vitrified microbead thermal insulation mortar.
Reason: The viscosity is high, the mortar is not easy to fall off, sag, and the construction is improved.
6. HPMC is a non-ionic cellulose ether, so what is non-ionic?
——Answer: In layman’s terms, non-ions are substances that do not ionize in water. Ionization refers to the process in which an electrolyte is dissociated into charged ions that can move freely in a specific solvent (such as water, alcohol). For example, sodium chloride (NaCl), the salt we eat every day, dissolves in water and ionizes to produce freely movable sodium ions (Na+) that are positively charged and chloride ions (Cl) that are negatively charged. That is to say, when HPMC is placed in water, it will not dissociate into charged ions, but exist in the form of molecules.
Post time: Apr-26-2023