What is the main component of concrete retarder? Generally speaking, it is not disclosed to the public. The editor of Anhui Yulong New Materials Co., Ltd. will take you today to learn about the main components of retarder. Retarder is not unique, there are concrete super retarder, alkali slag concrete retarder, oil well cement retarder, cement concrete composite super retarder, etc. Now we provide you with several retarder formulas:
Concrete super retarder formula:
Maltodextrin 73%
Citric acid 13%
p>Sodium pyrophosphate 14%
Oil well cement retarder formula:
20% polycopolymer solution 88%
50% Hydroxyethylene diphosphonic acid solution 12%
The multi-component copolymer solution is composed of 2.5% itaconic acid, 4% acrylic acid, 4% potassium persulfate initiator solution, 13.5% 2 -A solution of acrylamido-2-methylpropanesulfonic acid and 76% deionized water.
Cement retarder formula:
Phosphogypsum: 55%
Fly ash: 40%
Calcium material: 4 %
Activator: 1%
Inorganic retarder
1) Phosphate and metaphosphate retarder
Phosphate and metaphosphate retarder are the most studied inorganic retarder. The retarding effect of orthophosphoric acid (H3PO4) is not great, but the retarding effect of various phosphates is strong. At the same dosage, sodium pyrophosphate (Na2P2O7) has the strongest retarding effect among phosphate retarders.
2) Borax (Na2B4O7·10H2O)
It is highly hygroscopic and easily soluble in water and glycerol. The aqueous solution is weakly alkaline and easily weathers slowly in dry air.
3) Sodium fluorosilicate (Na2SiF6)
White crystalline substance, density 2.68g·cm, slightly soluble in water, insoluble in ethanol, corrosive, general dosage: 0.1-0.2% of cement dosage.
Organic retarder
Organic phosphonic acid (salt)
There are many types of organic phosphonic acid (salt), many of which are suitable for use as oil well cement Retarder.
What kind of concrete admixtures are used in summer and winter?
Depending on the needs, water-reducing admixtures are generally added. In summer, retarder is added. Because of the high temperature, retarder is needed to delay the admixture. The setting time of concrete can also prevent concrete from losing too quickly
In winter, water-reducing agents are also used, and early-strength agents and antifreeze can be added as needed; early-strength agents can increase the early strength of concrete and speed up the The time of removing the formwork can also slightly advance the setting time of the concrete. If the temperature is below 0 degrees, antifreeze can be added to prevent the concrete from freezing
Water-reducing agent must be added because the water-reducing agent can reduce the amount of concrete. Reduce water consumption, reduce cement consumption, save costs, and improve concrete strength
The concrete mixing station uses a compounding machine, which is generally compounded of water reducing agent, retarder, air entrainment, etc.
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