Preparation method of polycarboxylate superplasticizer with high viscosity reduction performance

Abstract

The invention discloses a preparation method of a polycarboxylate superplasticizer with high viscosity reduction performance. The preparation method comprises the following steps: reacting trifluoroethanol with a double bond-containing enoic acid acyl chloride compound to generate a viscosity-reducing functional monomer I, reacting maleic anhydride with a straight-chain diol compound to generate aviscosity-reducing functional monomer II, finally preparing a special solution A, a special solution B and a special solution C, and dropwise adding the solutions A, B and C into a water phase systemto react to obtain the finished product. Compared with common PCE, the polycarboxylate superplasticizer has a good viscosity reduction effect, and the flowing time and T500 are obviously shortened; an emulsion polymerization method is adopted, the reaction polymerization efficiency is high, the molecular weight distribution of the prepared product is more uniform, and the molecular structure andperformance of the product are more stable; and the phenomena of high viscosity, bottom scrabbling and the like caused by low water-binder ratio in the mixing process of the high-strength concrete canbe effectively solved.

Description

technical field [0001] The invention belongs to the field of concrete water reducers, in particular to a preparation method of a polycarboxylate water reducer with high viscosity-reducing performance. Background technique [0002] With the rapid development of the construction industry, modern buildings tend to be high-rise, lightweight and long-span. High-strength concrete is being widely used in infrastructure construction due to its high strength, good integrity, and low self-weight. . At present, the strength of high-strength concrete is mainly increased by reducing the water-cement ratio and increasing the amount of cementitious materials, but this will increase the viscosity of the concrete and reduce the fluidity, thereby reducing the pumping performance of the concrete and affecting the construction efficiency. , which largely limits the promotion and application of high-strength concrete. [0003] At present, it is generally used to solve this problem by increasin...

AI Technical Summary

Problems solved by technology

For example, in the authorized patent CN108192010A, a viscosity-reducing polycarboxylate superplasticizer was synthesized from ether macromonomers, ester-modified monomers, and unsaturated acid monomers. effect, but the overall synthesis process is more complicated, the raw materials involved are more expensive, and ethanol is selected as the solvent, which is not convenient for large-scale industrial production

In the authorized patent CN105601826A, unsaturated carboxylic acid monomers, unsaturated phosphonic acid monomers and UV-active monomers are synthesized into macromolecules, and then synthesized with acrylamide and monomers to obtain a viscosity-reducing polycarboxylate water reducer. The whole is complicated, and the process of vacuum distillation and toxic solvents such as toluene are used, which does not conform to the concept of green environmental protection

Patent application CN104262550A provides a method for synthesizing a viscosity-reducing polycarboxylate superplasticizer, but the overall synthesis route is relatively long, and the problems of low yield and low product purity are prone to occur

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