High Water Retention Agent Construction Grade HPMC Used in Drymix MortarJune 7th 2023
Each cellulose ether has the basic structure of cellulose-anhydroglucose structure. In the process of producing cellulose ether, the cellulose fiber is first heated in an alkaline solution, and then treated with an etherifying agent. The fibrous reaction product is purified and ground to form a uniform powder with a certain fineness.
In the production of MC, only methyl chloride is used as an etherifying agent; in addition to methyl chloride, propylene oxide is also used to obtain hydroxypropyl substituents in the production of SLEOCHEM HPMC. Various cellulose ethers have different methyl and hydroxypropyl substitution rates, which affect the organic compatibility and thermal gel temperature of the cellulose ether solution.
The Application of cellulose ether in putty
Water-resistant putty is divided into dry powder putty and putty paste. Generally, two types of putty are modified methyl cellulose and hydroxypropyl methyl. The viscosity specification is generally between 30,000 and 60,000 cps. The main function of cellulose in putty is water retention, adhesion, lubrication and so on. Since the putty formulas of various manufacturers are different, some are gray calcium, light calcium, white cement, etc., and some are gypsum powder, gray calcium, light calcium, etc., so the specifications and viscosity of the cellulose and the infiltration of the two formulas are different. The added amount is about 2‰-3‰.
In the construction of the wall putty, since the base surface of the wall has a certain degree of water absorption rate of the brick wall is 13%, and the concrete is 3-5%), plus the external evaporation, if the putty loses water too fast , It will lead to cracks or de-powdering, which will weaken the strength of the putty. For this reason, adding cellulose ether will solve this problem. But the quality of the filler, especially the quality of ash calcium is also extremely important.
Because cellulose has a higher viscosity, it also enhances the buoyancy of the putty, avoids the sagging phenomenon during construction, and is more comfortable and labor-saving after scraping. It is that the cellulose ether should be added appropriately in the powder putty. Its production and use are more convenient. The filler and the auxiliary agent can be evenly mixed with the dry powder. The construction is also more convenient. The on-site water distribution is as much as you need.
The Application of cellulose ether in concrete mortar
In the concrete mortar, to achieve the ultimate strength, the cement must be completely hydrated. Especially in the summer construction, the concrete mortar loses too much water. Take complete hydration measures to maintain and sprinkle water. The first method is to cause water. Resource waste and inconvenient operation. The key is that the water is only the internal hydration is still incomplete. Therefore, the method to solve this problem is to add water-retaining agent cellulose to mortar concrete and generally choose hydroxypropyl methyl or methyl fiber. The viscosity specification is between 20000–60000cps, and the addition amount is 2%–3%. The water retention rate can be increased to more than 85%. The method of use in mortar concrete is to mix the dry powder uniformly and then add water.