Carboxylic acids graft copolymer concrete strengthening agent

Abstract

This invention is a carboxylic acids graft copolymer concrete bao tan agent. The procedures are that 1) single alkyl polyether or double hydroxy group polyether and their compound said by general formula (1) is grafting reacted to generate big monomer a with C=C with dyadic unsaturated carboxylic acid or anhydride in condition of acid catalyst. 2) Compound an and monomer b is compounded copolymerized with weight ratio is 70-90% and 3-30%. This invention can greatly improve the slump constant loss of traditional naphthalene system water reducing agent, and improve its dispersibility at the same time. Coagulation time of concrete doesní»t prolong, it has good plastic keeping effect to medium and low slump constant concrete or big degree of fluidity concrete. It has good adaptability to other high efficiency water reducing agent. Good degree of fluidity keeping ability is on it whether coordinated with traditional naphthalene system water reducing agent or melamine system water reducing agent or new style polyocarboxy acid system dispersibility. There is no three wastes during its procedure.

Description

technical field [0001] The invention belongs to the technical field of concrete admixtures in building materials, and in particular relates to a carboxylic acid graft copolymer that can be used as a high-efficiency slump-retaining agent for concrete. Background technique [0002] With the development of transportation, hydropower, municipal and other construction projects, the gradual rise of high-span bridges, hundreds of stories of high-rise buildings, and oil drilling platforms, offshore airports, offshore cities, and submarine tunnels, the construction performance and strength of concrete The requirements for indicators and durability are getting higher and higher, and almost all of them require the use of pumped concrete, and high-efficiency water reducers are the fifth component that is indispensable for the preparation of pumped concrete. Pumping concrete requires long-distance transportation and construction under high temperature conditions, which will inevitably le...

AI Technical Summary

Problems solved by technology

Although reactive polymers are very effective in solving the problem of concrete slump, they also have fatal shortcomings. Its storage stability is poor, and its plastic retention effect decreases with the prolongation of storage time. Synthesized in a solvent, which is very polluting to the environment and is not conducive to sustainable development

[0009] At present, the new type of carboxylic acid graft copolymer superplasticizer has become a worldwide research hotspot due to its good dispersibility, strong slump retention ability, and many variable factors in molecular structure. However, from the perspective of China's national conditions, Carboxylic acid water reducers are basically foreign products, the price is too high, it is difficult to promote and apply quickly and in a large area. For a long period of time in the future, large-scale construction projects in China will basically be based on naphthalene-based water reducers. Therefore, how to effectively control its slump loss will be a major issue that must be solved in the further promotion and application of high-efficiency water reducers and the development of new technologies for concrete.

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