Novel polycarboxylic acid high-performance nano seed crystal early-strength water reduction complex agent and preparation method thereof

Abstract

The invention discloses a novel polycarboxylic acid high-performance nano seed crystal early-strength water reduction complex agent and a preparation method thereof. The novel polycarboxylic acid high-performance nano seed crystal early-strength water reduction complex agent comprises the following raw materials in percentage by weight: 5.5 to 12.5 percent of a base material, 4.5 to 10 percent ofsoluble calcium salt, 4 to 9 percent of soluble silicate, 2.5 to 5 percent of a stabilizer, 0.07 to 0.12 percent of a surfactant containing a functional monomer, 0.2 to 0.3 percent of a dispersant, 0.02 to 0.04 percent of a de-foaming agent and the balance of water, wherein the calcium-silicon ratio is 1 to 1.6. A polycarboxylic acid water reduction agent and a strong crystal nucleus are used forassisting and promoting the generation of C-S-H gel in cement hydration and a cement hydration progress is accelerated, so that the early strength of concrete is obviously improved and the long-term strength is not decreased; the stabilizer, the surfactant and the dispersant cooperatively act on the surface of the crystal nucleus, so that the state of an obtained complex agent solution is uniformand stable; a preparation technology of the complex agent has a simple process; the obtained solution is uniform and stable, has no sediment and has factors which easily reduce the durability of a concrete structure, such as low alkali, no triethanolamine, no chlorine and no sulfate; and a prefabricated part production process does not need high-temperature autoclave curing and energy saving and emission reduction are facilitated.

Description

technical field [0001] The invention relates to the technical field of special early-strength concrete admixtures for prefabricated components, in particular to a novel polycarboxylic acid high-performance nano-seed crystal early-strength water-reducing composite agent and a preparation method thereof. Background technique [0002] Concrete early-strength additives are in great demand in the production of precast components and concrete applications because they can accelerate the hydration rate of cement and promote the development of concrete early strength. At present, the most commonly used early-strength agents are mainly inorganic and organic types, but these early-strength agents are likely to have adverse effects on the workability and durability of concrete, such as: chloride-based early-strength agents have a corrosive effect on steel bars; Sulfate-based early-strength agents themselves have defects, and it is easy to reduce the impermeability and corrosion resista...

AI Technical Summary

Problems solved by technology

At present, the most widely used accelerators are mainly inorganic and organic, but these accelerators are likely to have adverse effects on the workability and durability of concrete, such as: chloride-based accelerators have a corrosive effect on steel bars; Sulfate-based early-strength agents have their own defects, and they are easy to reduce the impermeability and corrosion resistance of concrete; organic-based early-strength agents such as triethanolamine-based early-strength agents, improper dosage control can easily lead to super-retarded or fast-set; there are also some early-strength The early-strength agent has poor early-strength effect, or affects the later strength, or the source of raw materials is difficult and the cost is high; and the component factory needs high-temperature autoclaved curing at the same time when adding the early-strength agent. This process is not only high in equipment cost and energy consumption, but also not conducive Environmentally friendly, therefore, research and develop a new type of early strength agent to improve the production efficiency of prefabricated components, and is conducive to energy saving and emission reduction, without affecting the working performance and durability of concrete

[0003] At present, there are two types of early strength agents that can improve prefabricated components, one is polycarboxylate early strength superplasticizer, and the other is crystal nucleus type early strength agent. The former requires high-temperature autoclaved curing in the production and application of prefabricated components. It is not conducive to energy saving and emission reduction, and many admixtures not only have high alkali content but also contain chloride ions, sulfate ions, triethanolamine and other factors that are not conducive to the durability of concrete structures; the second crystal nucleus early strength agent is stronger than polycarboxylate early strength Water reducing agent not only does not require high-temperature autoclaved curing, but also does not contain factors that are likely to reduce the durability of concrete and corrode steel bars. It is environmentally friendly and pollution-free. Mixed with water reducing agent to achieve the required slump

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