Starch ether is mainly used in construction mortar, which can affect the consistency of mortar based on gypsum, cement and lime, and change the construction and sag resistance of mortar. Starch ethers are usually used in conjunction with non-modified and modified cellulose ethers. It is suitable for both neutral and alkaline systems, and is compatible with most additives in gypsum and cement products (such as surfactants, MC, starch and polyvinyl acetate and other water-soluble polymers).
The characteristics of starch ether mainly as bellow:
(1) Improve sag resistance;
(2) Improve constructability;
(3) Higher mortar yield.
What is the main function of starch ether in gypsum-based dry mortar?
Answer: Starch ether is one of the main additives of dry powder mortar. It can be compatible with other additives. It is widely used in tile adhesives, repair mortars, plastering gypsum, interior and exterior wall putty, gypsum-based caulking and filling materials, interface agents, masonry In mortars, it is also suitable for hand or spray application with cement-based or gypsum-based mortars. It works as follows:
(1) Starch ether is usually used in combination with methyl cellulose ether, which shows a good synergistic effect between the two. Adding an appropriate amount of starch ether to methyl cellulose ether can significantly improve the sag resistance and slip resistance of the mortar , with a high yield value.
(2) Adding an appropriate amount of starch ether to the mortar containing methyl cellulose ether can significantly increase the consistency of the mortar, improve the fluidity, and make the construction smooth and smooth.
(3) Adding an appropriate amount of starch ether to the mortar containing methyl cellulose ether can increase the water retention of the mortar and prolong the open time.
What are the application advantages and storage methods of starch ether?
Answer: It can be used as an admixture for cement-based products, gypsum-based products and ash-calcium products.
(1) Advantages and applications:
a. It has a thickening effect on the mortar, can thicken quickly, and has good lubricity;
b. The dosage is small, and a very low dosage can achieve a high effect;
c. Improve the anti-slide ability of bonded mortar;
d. extend the open time of the material;
e. Improve the operating performance of the material and make the operation smoother.
(2) Storage:
The product is susceptible to moisture and must be stored in a dry and cool place in the original packaging. It is best to use it within 12 months. (It is recommended to be used in conjunction with high-viscosity cellulose ether, and the general ratio of cellulose ether to starch ether is 7:3~8:2)
What is the role of methyl cellulose ether in dry powder mortar?
A: Methyl hydroxyethyl cellulose ether (MHEC) and methyl hydroxypropyl cellulose ether (HPMC) are collectively referred to as methyl cellulose ether.
In the field of dry powder mortar, methyl cellulose ether is an important modified material for dry powder mortar such as plastering mortar, plastering gypsum, tile adhesive, putty, self-leveling material, spray mortar, wallpaper adhesive and caulking material. In various dry powder mortars, methyl cellulose ether mainly plays the role of water retention and thickening.
What is the production process of cellulose ether ?
Answer: Firstly, the cellulose raw material is crushed, then alkalized and pulped under the action of caustic soda. Add olefin oxide (such as ethylene oxide or propylene oxide) and methyl chloride for etherification. Finally, water washing and purification are carried out to finally obtain a white powder. This powder, especially its aqueous solution, has interesting physical properties. The cellulose ether used in the construction industry is methyl hydroxyethyl cellulose ether or methyl hydroxypropyl cellulose (abbreviated as MHEC or MHPC, or a more simplified name MC). This product plays a very important role in the field of dry powder mortar. important role.