Polycarboxylic acid high-performance water reducing agent and preparation method thereof

Abstract

The invention discloses a polycarboxylic acid high-performance water reducing agent and a preparation method thereof. Raw materials of the water reducing agent comprise the following materials in parts by weight: 42-52 parts of sodium gluconate, 65-78 parts of a polycarboxylate master batch, 3-15 parts of an air entraining agent, 95-105 parts of unsaturated polyoxyethylene ether, 0.1-4 parts of a chain transfer agent, 0.1-4 parts of an oxidizing agent, 0.1-2 parts of a reducing agent, 140-160 parts of deionized water, 0.06-0.4 part of a micro crosslinking agent, 0.1-0.8 part of ascorbic acid, 0.01-0.4 part of ferrous sulfate heptahydrate, and 10-25 parts of a sodium hydroxide solution. The preparation method comprises the following steps: the polycarboxylate master batch, the air entraining agent, the oxidizing agent and the deionized water are mixed, and the chain transfer agent is added to obtain a first solution; the reducing agent, the ascorbic acid and the deionized water are mixed to obtain a second solution; and the micro crosslinking agent, the unsaturated polyoxyethylene ether, the deionized water, the sodium gluconate and the ferrous sulfate heptahydrate are mixed, the first solution and the second solution are added dropwise, and the sodium hydroxide solution is added to obtain the water reducing agent. The polycarboxylic acid high-performance water reducing agent has the characteristics of high applicability, a high water-reducing rate, good slump-retaining performance, good frost resistance and good carbonization resistance.

Description

technical field [0001] The invention relates to the technical field of concrete water reducers, in particular to a polycarboxylate high-performance water reducer and a preparation method thereof. Background technique [0002] Due to the characteristics of high workability, high strength, high durability and volume stability, high-performance concrete is widely used in the construction of major bridges, highways, tunnels and large buildings. Among them, water reducing agent is an indispensable component of high-performance concrete one of the components. Polycarboxylate superplasticizer has the advantages of low dosage, high water reducing rate, good slump retention, large degree of freedom in molecular structure design, and environmental friendliness. Research hotspots and development priorities in the pharmaceutical field. Compared with high-efficiency water-reducing agents such as naphthalene-based, melamine-based, and sulfamate, polycarboxylate-based water-reducing agen...

AI Technical Summary

Problems solved by technology

In the prior art, a variety of ether polycarboxylate superplasticizers with different molecular structures and performance characteristics have appeared, but the existing ether polycarboxylate superplasticizers have some shortcomings, such as the applicability to some cement Not strong, for concrete with high mud content and high stone powder, it is prone to the defect of insufficient slump retention performance, and it is prone to bleeding due to high water reducing rate, especially in the proportion of medium and low grade concrete, the workability not good