When making waterproof coatings, water-reducing agents need to be added. What is the specific role of adding them in the actual production process? Many novices may not understand. An experienced driver will give you a comprehensive analysis.
There is no doubt about the importance of waterproofing in home life. If you want a high-quality waterproofing, choosing a good waterproof coating is the key first step. However, there are all kinds of waterproof coatings on the market. Many consumers are confused by professional terms such as "polymer", "single component", "water-based", "acrylate", etc. What kind of waterproof coatings should be used for interior decoration? How to choose waterproof coatings? The reporter went to the building materials supermarket and asked industry insiders to explain the properties, advantages and disadvantages of waterproof coatings currently on the market, hoping to give consumers who choose waterproof coatings Helps. Waterproof coatings are divided into four major categories. Although there are many waterproof coatings on the market and on the Internet, such as "two-component polymer waterproof coating" and "single-component polyurethane waterproof coating". Due to the different characteristics of waterproof materials, corresponding The construction methods also have their own characteristics. For waterproof coatings, due to the variety of types, the painting methods are also different.
To understand waterproofing, in addition to knowing the types and effects of materials, their corresponding The construction method is the key for everyone to quickly understand waterproofing. For different construction objects and waterproof materials of different properties, we must adopt different construction methods to obtain the best coating quality and achieve the expected waterproofing effect
Water reducing agent can reduce unit water consumption without affecting the workability of concrete; after mixing cement and water, a hydration reaction occurs, and some flocculation-like structures appear, which wrap a lot of mixing water, thus reducing the It improves the workability of fresh concrete (also known as workability, which mainly refers to the performance of fresh concrete that can remain uniform and dense without delamination and segregation during construction, that is, during mixing, transportation, pouring, etc.). Construction In order to maintain the required workability, the amount of mixing water must be increased accordingly. Because the increase in water amount will form excessive pores in the cement stone structure, which will seriously affect the physical and mechanical properties of hardened concrete, if these wrapped moisture can be When released, the water consumption of concrete can be greatly reduced. In the process of preparing concrete, adding an appropriate amount of water-reducing agent can play such a role well.
Adding water-reducing agent to concrete After the water-reducing agent is added, the hydrophobic groups of the water-reducing agent are directionally adsorbed on the surface of the cement particles, while the hydrophilic groups point to the aqueous solution, forming a single-molecule or multi-layer adsorption film. Due to the directional adsorption of the surfactant, the surface of the cement particles is banded There are charges with the same sign, so under the action of same-sex repulsion, not only can the cement-water system be in a relatively stable suspension state, but also the flocculation-like structure formed by the cement in the early stage of adding water can be dispersed and disintegrated, thereby disintegrating the flocculation structure. The water inside is released to achieve the purpose of water reduction. After the water-reducing agent is added, not only can the workability of fresh concrete be improved, but also the water-cement ratio in the concrete will be greatly reduced, so that the internal pore volume of the cement stone will be reduced. The cement stone has a very large sand and gravel content. The cement stone is denser and the compressive strength of concrete is significantly improved. The addition of water reducing agent also affects the hydration speed and setting time of cement. These properties are practical in practical applications. Both are very important.</p
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