Synthetic method of side-chain adsorption type concrete super-plasticizer

Abstract

The invention relates to a synthetic method of a side-chain adsorption type concrete super-plasticizer. By using an unsaturated monomer, an unsaturated initiator, a transition metal complex, a carboxylic small monomer and the like as main raw materials and through the method of auto-polymerization, hydrolysis and graft copolymerization, the side-chain adsorption type concrete super-plasticizer issynthesized. The synthetic method specifically comprises the following steps: the unsaturated monomer, which is used as a reactant, is subjected to atom transfer radical polymerization (ATRP) in an initiating system composed of the unsaturated initiator, transition metal halide and a ligand so as to obtain an unsaturated macromonomer; then, the macromonomer is subjected to hydrolysis to obtain ananionic macromonomer; and the anionic macromonomer and the carboxylic small monomer are subjected to radical graft copolymerization under the action of an initiator and a chain transfer agent to prepare the side-chain adsorption type concrete super-plasticizer. The synthetic method of the invention has controllable process and simple step, is convenient and efficient, and is energy-saving and environmentally-friendly. Through innovative design of the molecular structure, the side-chain adsorption type concrete super-plasticizer is synthesized, multiple excellent effects of water reduction andslump retaining and the effect of inhibiting side effect of clay are realized, and the types of the concrete super-plasticizer are enriched.

Description

technical field [0001] The invention relates to the technical field of a superplasticizer for cement concrete, in particular to a superplasticizer that uses unsaturated monomers to self-polymerize and then hydrolyze to form anionic macromonomers, and then graft copolymerizes with carboxylic acid small monomers to form side plasticizers. The specific preparation method of the chain adsorption type concrete superplasticizer. Background technique [0002] The deepening of urbanization and the rapid expansion of infrastructure have led to the rapid development of the construction industry. The amount of concrete and cement is increasing. As one of the important components of concrete, superplasticizers have become a hot spot in concrete research and development. The emergence of polycarboxylate superplasticizers with low dosage, high water-reducing rate and good slump retention has solved the problems of low water-reducing rate and retarded setting of ordinary lignosulfonate-bas...

AI Technical Summary

Problems solved by technology

However, the above-mentioned synthesis methods all have certain deficiencies. Researchers mostly focus on achieving water-reducing dispersion, anti-mud, flocculation and other properties through modification and modification, but seldom use controllable polymerization methods to innovate and synthesize anionic side chains. Macromonomer, and based on this synthetic side chain adsorption type concrete superplasticizer, it is difficult to truly expand structural innovation and performance optimization

Only simple main chain or polyether side chain modification limits its application in the field of concrete superplasticizers

Therefore, this requires concrete superplasticizers to achieve fundamental innovations in molecular structure. They must not only have working properties such as water reduction and slump protection, but also have resistance to external environmental influences such as mud resistance. Simple, low cost, abundant and extensive raw materials are also the guarantee for industrialized production and large-scale promotion and application. There are no reports on this aspect at home and abroad.

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