Preparation method of solid polycarboxylate superplasticizer

Abstract

The invention discloses a preparation method of a solid polycarboxylate superplasticizer. The method comprises the following steps of: (1) adding unsaturated polyoxyethylene ether to a reaction device, and heating the unsaturated polyoxyethylene ether until the unsaturated polyoxyethylene ether is completely melted; (2) under the heat preservation condition of 50-70 DEG C, adding 1 / 3 of a first mixture to the material obtained in the step (1) for performing stirring evenly, adding a first initiator and 1 / 4 of a second initiator at a time, performing stirring for 2-3 minutes, and then dropwiseadding a second mixture into a reactor separately, wherein the dropwise adding time is 2-4 hours; after 1 / 4 of dropwise adding time, feeding 1 / 4 of the second initiator at a time; after 2 / 4 of dropwise adding time, feeding 1 / 4 of the second initiator at a time; after 3 / 4 of dropwise adding time, feeding 1 / 4 of remaining second initiator at a time; further reacting for 1-2 hours after dropwise adding is completed; and adding a neutralizer to adjust pH to be 6-7 after reacting is completed, pouring out a reaction product while the reaction product is hot, and cooling the reaction product to roomtemperature to obtain a solid polycarboxylate superplasticizer.

Description

technical field [0001] The invention belongs to the technical field of building admixtures, and in particular relates to a preparation method of a solid polycarboxylate water reducer. Background technique [0002] With the continuous development and progress of my country's construction industry, the demand for concrete admixtures continues to increase. Water reducer is the most commonly used and the largest amount of admixture in concrete, which can greatly improve the working performance of concrete. Polycarboxylate superplasticizer, as the third generation of high-performance superplasticizer after naphthalene series, overcomes some disadvantages of traditional superplasticizers. With its high water reducing rate, small slump loss and large degree of freedom in molecular design, The synthesis process is simple, green and environmentally friendly, and has been widely used in the field of concrete engineering technology. [0003] In the prior art, the polycarboxylate supe...

AI Technical Summary

Problems solved by technology

However, this technical solution requires high-pressure dehydration after the polymerization reaction is completed, and the slices are broken at low temperature. Although the glass transition temperature regulator is introduced to increase the slice temperature, the energy consumption is still high and the preparation process is complicated.

Images