A kind of polycarboxylate superplasticizer and its normal temperature preparation method

Abstract

The invention discloses a polycarboxylate water reducer and a normal temperature preparation method thereof. It is characterized in that it consists of 27.5-31% by weight of unsaturated polyoxyethylene ether, 2.6-3.0% by weight of unsaturated carboxylic acid, 0.26-0.43% by weight of organosilicon monomer, and 4.5-8.0% by weight of lignosulfonic acid Salt, 0.030-0.08% by weight of reducing agent, 0.16-0.30% by weight of oxidant, 0.041-0.063% by weight of transfer agent, 1.0-1.16% by weight of alkaline regulator and 60% by weight of water are prepared at normal temperature. The obtained polycarboxylate superplasticizer has a high water-reducing rate and good slump retention performance, and solves the adaptability problem between the polycarboxylate superplasticizer and concrete raw materials, and has good water retention and cohesion in the application of concrete, especially machine-made sand concrete. . The raw material lignosulfonate is rich in sources, renewable, suitable for large-scale industrial production, and has broad market prospects.

Description

technical field [0001] The invention relates to the technical field of concrete admixtures in building materials, in particular to a polycarboxylate water reducer and a preparation method thereof at normal temperature. Background technique [0002] Polycarboxylate high-performance water reducer is the basic material for preparing high-performance concrete. At present, there are many raw materials and synthesis processes used to prepare polycarboxylate high-performance water reducer. Different reaction raw materials and synthesis processes have great influence on the preparation of polycarboxylate water reducer. Structure and performance have a great influence. The advantages of polycarboxylate high-performance water-reducing agent are that it has a large degree of freedom in molecular structure design, less environmental pollution, adjustable functions, and high water-reducing rate. It has been widely used in concrete engineering in recent years. [0003] However, the tradi...

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Problems solved by technology

[0003] However, the traditional polycarboxylate superplasticizer is prepared by free radical polymerization by heating and heating method. Most of the production requires boiler heating, which consumes a lot of energy. After the polymerization reaction, the system needs to be cooled to a certain temperature before the alkali solution can be neutralized. pH value, the whole production process takes a long time and the production cost is high

Secondly, the raw materials used in the production of polycarboxylate superplasticizers mainly come from the increasingly scarce non-renewable resource petroleum, which is expensive, especially some domestic raw materials still rely on imports, so the cost is relatively high

[0004] In addition, due to the wide variety of raw materials used in the production of concrete and the large regional differences, it is often easy to cause inadaptability of polycarboxylate superplasticizers and ground materials, especially with the decline in the mining of natural river sand, machine-made sand has gradually replaced Natural sand has become an important raw material for concrete production, and due to irregular production, the gradation and particle type of machine-made sand will seriously affect the performance of concrete, resulting in segregation and bleeding of freshly mixed concrete, resulting in quality accidents in concrete engineering

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