Why does water-reducing agent produce directional adsorption on the surface of cement particles?
Views : 86
Author : Lzh
Update time : 2023-02-06 12:30:11
What is water-reducing agent? Water-reducing agentis a concrete admixture that can reduce water consumption for mixing while keeping the concrete slump unchanged. Most are anionic surfactants, such as lignosulfonate, naphthalenesulfonate formaldehyde polymer, etc. Role: adding concrete mixture can disperse cement particles, reduce unit water consumption, improve the fluidity of concrete mixture, or reduce unit cement consumption to save cement.
Action mechanism of water reducer (1) After mixing the dispersed cement with water, due to the hydration of the cement particles, the surface of the cement particles forms a double electric layer structure, making it form a solvated water film. Moreover, the surface of the cement particles has opposite charges, making the cement slurry form a flocculation structure so that 10%~30% of the mixed water is wrapped in the cement particles, which cannot participate in free flow and lubrication, thus affecting the fluidity of the concrete mixture (2) The hydrophilic group in the lubricating water-reducing agent has a strong polarity. Therefore, the adsorption film of the water-reducing agent on the surface of the cement particles can form a stable solvated water film with water molecules. This water film has a good lubrication effect and can effectively reduce the sliding resistance between the cement particles, thus further improving the fluidity of the concrete.
Steric effect of water-reducing agent In cement slurry mixed with a water-reducing agent, the long chain of organic molecules of the water-reducing agent presents various adsorption states on the surface of cement particles. The different adsorption states are caused by the different molecular chain structures of high-efficiency water-reducing agents, which directly affects the time change of the slump of concrete mixed with this type of water-reducing agent. Some studies show that the adsorption state of the Cai series and melamine series water-reducing agent is the rod-like chain, so it is straight adsorption; the electrostatic repulsion is weak. The result is that the Zeta potential decreases rapidly, and the electrostatic balance is easily destroyed with the development of the cement hydration process, which makes van der Waals gravity dominant, and the slump changes greatly over time.
Price of water-reducing agent Water-reducing agent particle size and purity will affect the product's price, and the purchase volume can also affect the cost of the water-reducing agent. A large amount of large amount will be lower. The price of the water-reducing agent can be found on our company's official website.
Water-reducing agent supplier Luoyang Tongrun Nano Technology Co. Ltd. (TRUNNANO) Luoyang City, Henan Province, China, is a reliable and high-quality global chemical material supplier and manufacturer. It has more than 12 years of experience providing ultra-high quality chemicals and nanotechnology materials, including water-reducing agents, nitride powder, graphite powder, sulfide powder, and 3D printing powder. If you are looking for a high-quality and cost-effective water-reducing agent, you are welcome to contact usor inquire at any time.
