Preparation method of solid polycarboxylic acid water reducing agent

Abstract

The invention relates to the technical field of polycarboxylic acid water reducing agents, and in particular relates to a preparation method of a solid polycarboxylic acid water reducing agent. The method comprises the following steps: performing heating dissolution on isopentenol polyethenoxy ether under the condition of a preset dissolution temperature; under the conditions of a preset reactiontemperature and protection of a nitrogen gas introduced into the dissolved isopentenol polyethenoxy ether, adding tetrahydrofurfuryl acrylate, Fe2O3 and potassium persulfate, adding a tetrahydrofurfuryl acrylate solution and a mercaptopropionic acid solution stepwise and dropwise at variable speeds, and performing a reaction to obtain the solid polycarboxylic acid water reducing agent; and performing cutting crushing operation on the solid polycarboxylic acid water reducing agent when the product is hot. According to the method provided by the invention, a double redox system is adopted, so that the overall efficiency of the polymerization reaction is improved, and the production effects are improved; phosphate is introduced, the phosphate group can greatly improve the molecular adsorptioncapacity of the solid polycarboxylic acid water reducing agent, and the solid polycarboxylic acid water reducing agent has the advantage of more resistance to a sulfate; and the solid polycarboxylicacid water reducing agent has better adaptability to various concrete and better water reducing effects.

Description

technical field [0001] The invention relates to the technical field of polycarboxylate water reducer, in particular to a preparation method of solid polycarboxylate water reducer. Background technique [0002] Although some progress has been made in the research and development of polycarboxylate superplasticizers in recent years, there are still some defects in production and application that affect the promotion and development of polycarboxylate superplasticizers. [0003] Foreign experts mainly focus on the mechanism of action of polycarboxylate high-efficiency superplasticizers, practical engineering applications, and changes in thermodynamic properties after being mixed with concrete. Domestic research started relatively late, mainly focusing on the selection of raw materials and process conditions. Optimization, production cost reduction and so on. [0004] At present, the solid content of polycarboxylate superplasticizers produced at home and abroad is generally bet...

AI Technical Summary

Problems solved by technology

If the monomer concentration in the reaction system is too high, the concentration of the entire reaction system will also increase, and the automatic acceleration of chain polymerization is difficult to control, which may hinder the rearrangement between chain segments and even terminate the polymerization reaction. Continue, resulting in poor performance of the final synthetic water reducer and the risk of gelation

With the extension of the reaction time, the viscosity of the system will continue to increase, and the frequency of activities between the reaction monomers will decrease significantly, resulting in uneven polymerization reactions and high and low product conversion rates, which have a great impact on the final performance of the product. Impact

[0006] However, the existing polycarboxylate water reducers still have the problems of low production efficiency and poor water reducing effect

Images