Water-reducing agent for polycarboxylate concrete and preparation and application thereof

Abstract

The invention provides a water-reducing agent for polycarboxylate concrete and preparation method thereof. The water-reducing agent is polymerized with two types of monomer, isobutylene polyoxyethylene ether and unsaturated carboxylic acid. The molar ratio of the aforementioned isobutylene polyoxyethylene ether and unsaturated carboxylic acid is 1: (3.5-5.5). The invented polycarboxylate water-reducing agent has relatively high water-reducing ratio, excellent net paste liquidity, and strong adaptability, thus ensuring superior workability and durability for concrete. The present invention selects the oxidation revivification system to produce free radicals, so that the polymerization reaction can be done under normal temperature. The present invention lowers reaction time, can substantially save energy consumption, increases production efficiency and saves labor costs. The present invention reduces environmental pollution and is suitable for industrialized applications.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to a polycarboxylate concrete water reducer and its preparation method and application. Background technique [0002] As an important admixture of cement concrete, the quality of water reducing agent has a crucial impact on the quality of physical engineering. Among them, the polycarboxylate high-performance water reducing agent not only has the advantages of high water reducing rate, can improve the pore structure and compactness of concrete, but also can control the slump loss of concrete, as well as the air-entraining, retarding, and bleeding of concrete. And other issues. In addition, it has good compatibility with different types of cement, which can make the concrete have high fluidity even at low content, and also has low viscosity and slump at low water-cement ratio. The characteristics of small changes over time. Therefore, the development and prom...

AI Technical Summary

Problems solved by technology

For example, the invention patent with the publication number CN101792281A discloses a synthesis method of polycarboxylate water reducer, the reaction starting temperature is 70-90°C, and the reaction time is as long as 6-8h. The reaction temperature is high, the time is long, and the energy consumption High, the preparation method of the raw material is complicated and the use of toluene solvent pollutes the environment. In addition, the invention patent with the publication number CN101575403 discloses a preparation method of polycarboxylate water reducer. The reaction temperature of the system needs to be greater than 80°C for the polymerization reaction to occur

[0004] my country's research on polycarboxylate superplasticizers started late, a large part of the technology is not particularly mature, and the source and quality of materials are not stable. In order to pursue high water-reducing rates while developing rapidly, the superplasticizers on the market Product quality varies, good and bad vary, and its performance and effectiveness cannot be effectively tested in the laboratory of conventional construction projects, resulting in defects such as bleeding, hardening, and poor workability of many polycarboxylate superplasticizers in the actual application process; Moreover, there are many cement factories in my country, and the types, ingredients, and processes of cement are not the same, resulting in poor compatibility between most polycarboxylate water reducers and cement, and weak adaptability to the environment, which brings great difficulties to construction.