Preparation method of high-solid-content early-strength polycarboxylate superplasticizer

Abstract

The invention relates to a preparation method of a high-solid-content early-strength polycarboxylate superplasticizer, which comprises the following steps: (1) adding unsaturated polyoxyethylene ether monomer and sulfonic functional monomer into water to prepare a base material with the concentration of 40-50%, and stirring and dissolving at the temperature of 5-10 DEG C; (2) after the unsaturated polyoxyethylene ether monomer and the sulfonic functional monomer in the step (1) are completely dissolved, adding an oxidizing agent at one time or gradually dropwise adding in a stirring state; (3) after the reaction in the step (2) is carried out for 5-15 minutes, preparing a 4-8% mixed solution B from a chain transfer agent and a reducing agent, and preparing a 15-20% solution A from an alkylene functional monomer; adding the solution A and the solution B into a flask at one time to react for 1.5-2.5 hours or gradually dropwise adding the solution A and the solution B into the flask for 3-3.5 hours by using a peristaltic pump to react; and (4) after the reaction in the step (3) is finished, carrying out heat preservation and aging for 0.5-1 hour, and adding an alkaline neutralizer accounting for 5-6% of the total mass at one time for neutralization. Compared with the traditional 40% solid content polycarboxylate superplasticizer, the polycarboxylate superplasticizer provided by the invention has the advantages of high production efficiency, high effective storage rate, good dispersibility and green and environment-friendly production process, and can obviously improve the early strength of concrete.

Description

technical field [0001] The invention relates to the technical field of concrete admixtures, and more particularly, to a preparation method of a high-solid and early-strength polycarboxylate water-reducing agent. Background technique [0002] Concrete is one of the largest consumables in the building materials industry and is widely used in residential, highway, railway, bridge and other construction projects. The early strength requirements are getting higher and higher. Its demand has also increased year by year, which has driven the application and development of concrete water reducers. As one of the important components to improve the performance of ready-mixed concrete, water reducer is mainly reflected in (1) reducing the amount of concrete mixing water, thereby improving the strength of concrete; (2) improving the working performance of concrete without affecting the (3) Reducing the amount of cement and saving costs under the condition that the durability and worki...

AI Technical Summary

Problems solved by technology

[0005] At present, the synthesis technology of polycarboxylate superplasticizer is relatively mature and stable, but there is still a situation of high synthesis temperature, which leads to large energy consumption, long reaction time and high production cost.

At present, there are few low-temperature synthesis processes in the market, and the low solid content of traditional polycarboxylate superplasticizers leads to increased production costs, labor costs, and transportation costs, as well as reduced production efficiency and storage efficiency. Therefore, low-temperature technology is used to produce polycarboxylates with high solid content Water reducing agent is of great significance

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