A kind of preparation method of ether highly dispersed high slump polycarboxylate water reducer

Abstract

The invention discloses a preparation method of an ether high-dispersion high-slump loss resistance polycarboxylate superplasticizer. The preparation method comprises the following steps: (1) conducting esterification reaction; (2) conducting copolymerization; and (3) conducting neutralization reaction. An esterification product comprising carboxyl and multiple ester groups is obtained through theesterification of unsaturated acid anhydride and polyether glycol, the ester group in the molecular group is gradually hydrolyzed under the alkaline condition of a cement paste, and the carboxyl having a water reducing effect is released, so that the slump loss resistance property is improved; the two ends of the prepared esterification product have C=C, the crosslinking point is provided, propercrosslinking is implemented in the copolymerization process, and slight crosslinking helps to improve the dispersion property, the roles of steric hindrance and intercalation resistance are better played, and the ether high-dispersion high-slump loss resistance polycarboxylate superplasticizer is well adapted to the raw materials of sands and stones.

Description

technical field [0001] The invention belongs to the technical field of building admixtures, and in particular relates to a preparation method of an ether-based highly dispersed and high-slump polycarboxylate water-reducer. Background technique [0002] In today's world, social economy is developing vigorously, urban construction is advancing by leaps and bounds, followed by the rapid rise of construction related to transportation, water and electricity, municipal administration, etc., the continuous emergence of high-rise buildings and the improvement of construction material construction requirements, the reliability of concrete The requirements for pumpability are getting higher and higher, and high-efficiency water reducers are an essential part of pumping, and polycarboxylate water reducers have become an important part of it. However, for a long time, the use of concrete has been troubled by how to effectively control the slump loss. The pumped concrete produced from t...

AI Technical Summary

Problems solved by technology

However, for a long time, the use of concrete has been plagued by the problem of how to effectively control the slump loss

The pumped concrete produced from the concrete mixing plant often needs long-distance transportation, and the construction environment is different, which will inevitably lead to the loss of concrete slump, which will affect the construction of concrete

Although its slump retention ability can be improved by adding retarders such as sodium gluconate, sucrose or organic phosphate, it cannot fundamentally solve the problem of slump loss

However, most slow-release polycarboxylate superplasticizers have a low initial water-reducing rate and too fast a slow-release speed, which often causes bleeding and segregation in long-distance mixer trucks, causing great difficulties in the construction process.

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