Viscosity-reducing tannic acid-based star-shaped polycarboxylate superplasticizer and preparation method thereof

Abstract

The invention discloses a viscosity-reducing tannic acid-based star-shaped polycarboxylate superplasticizer and a preparation method thereof. The water reducing agent is a copolymer formed by polymerizing raw materials including unsaturated polyether macromonomers, hydroxyethyl methacrylate phosphate, N-methylallylamine modified tannic acid functional monomers and acrylic acid in the presence of an initiator and a chain transfer agent through a free radical copolymerization reaction, wherein the unsaturated polyether macromonomer is any one or two selected from a group consisting of allyl polyoxyethylene ether (APEG), isobutene alcohol polyoxyethylene ether (HPEG) and isopentene polyoxyethylene ether (TPEG); the initiator is at least one selected from a group consisting of hydrogen peroxide, ammonium persulfate and potassium persulfate; and the chain transfer agent is at least one selected from a group consisting of mercaptopropionic acid, mercaptoacetic acid, sodium hypophosphite, sodium methallyl sulfonate and sodium allylsulfonate. The superplasticizer provided by the invention has the advantages of multiple molecular branched chains, low viscosity, small hydrodynamic volume andrich surface functional groups. Meanwhile, the preparation process is simple and easy to operate, low in cost and free of pollution.

Description

technical field [0001] The invention belongs to the technical field of building material admixtures, in particular to a viscosity-reducing tannic acid-based star polycarboxylate water reducer and a preparation method thereof. Background technique [0002] In recent years, the rapid development of building construction technology has put forward higher standards for the performance of concrete as the main building material. High-grade concrete has been widely used in bridge engineering and super high-rise buildings because of its high strength, good integrity and low weight. In order to improve the strength of concrete, high-strength cement is usually used, the amount of cementitious materials is increased, and the water-binder ratio is reduced. These measures will lead to increased concrete viscosity, slower flow speed, increased construction difficulty and lower construction efficiency. To a large extent The popularization and application of high grade concrete are limited...

AI Technical Summary

Problems solved by technology

Polycarboxylate-based high-performance water-reducing agents have only a few decades of development history, and neither the molecular structure nor the product range is rich enough to fully meet the current theoretical and application needs of concrete.

At present, researchers mainly focus on preparing comb-type polycarboxylate superplasticizers to solve the problems of concrete dispersion and dispersion retention through molecular structure design, but there are often problems such as single molecular structure, complicated preparation process, and high production cost.

Images