Alkenyl acid chloride alcoholysis to prepare the method of macromonomer synthesis polycarboxylate water reducing agent

Abstract

A method for preparing a macro-monomer synthesized polycarboxylate water reducer through alcoholysis of alkenyl-acyl chloride belongs to the field of water reducers. The method comprises the following steps: firstly polymerizing a cationic chain, and then reacting with the alkenyl-acyl chloride, thus obtaining a macro-monomer; then carrying out copolymerization on the macro-monomer and a carboxylic acid micro-monomer, i.e., polymerizing under an oxidization-reduction initiating system formed by high-valence cerate and alcohols by taking an unsaturated cationic quaternary ammonium salt monomer as a reactant, thus obtaining a terminal hydroxyl cationic long chain; then respectively enabling the terminal hydroxyl cationic long chain and polyethylene glycol monomothyl ether to react with the alkenyl-acyl chloride respectively, thus preparing macro-monomers with different structures; then carrying out free radical polymerization on the macro-monomers and unsaturated carboxylic acid micro-monomers, thus obtaining the macro-monomer composite polycarboxylate water reducer. According to the method disclosed by the invention, the macro-monomers with different structures and functions are successfully synthesized through ways of polymerizing the cationic chain and respectively reacting with the alkenyl-acyl chloride by combining polyether, and a novel comb-structure polycarboxylate water reducer which takes a polycarboxyl acid as a main chain and the cationic long chain and the polyether as polybasic side chains can be finally obtained. A reaction technology is simple and easy, and multiple excellent effects of retaining slump through reducing water, resisting clay, and the like are realized.

Description

technical field [0001] The invention relates to the technical field of a polycarboxylic acid high-performance water reducer for concrete, in particular to a polycarboxylate high-performance water reducer that uses an unsaturated cationic quaternary ammonium salt to first polymerize and then react with alkenyl acid chloride to form a macromonomer and then react with unsaturated carboxylic acid to form a small monomer. The specific preparation method of monomer copolymerization into polycarboxylate water reducer. Background technique [0002] Because it can prevent the loss of concrete slump without causing obvious retardation, it can exert a high plasticizing effect at low dosage, and has good fluidity retention, large room for high performance, high degree of freedom in molecular structure, and good for concrete. Remarkable strengthening and shrinkage reduction effects, extremely low content of harmful substances and other technical performance characteristics, polycarboxyla...

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Problems solved by technology

However, the product of this invention only introduces cationic monomers (instead of introducing polycationic long side chains in the present invention) into the main chain of the molecular structure, which improves a certain water-reducing and dispersing effect, but does not give full play to different side chain structures. characteristics to achieve multiple effects such as water-reducing dispersion and high clay resistance, but also failed to achieve the purpose of molecular structure design method to realize the functional regulation of chemical admixtures

[0008] The polycarboxylate superplasticizers, flocculants or phase change energy storage materials described in the above patents each have certain excellent characteristics. However, the products obtained by the above synthesis methods all have certain deficiencies, and researchers mostly focus on realizing One of the properties of water reduction, flocculation, and energy storage, but failed to achieve water collection and reduction through the method of polymerizing cationic side chains and polyether side chains and grafting copolymerization under the alkenyl chloride alcoholysis hypervalent cerium salt initiation system -Composite functional chemical admixture with application properties such as slump retention, dispersion and mud resistance

The method of only introducing cationic blocks through the main chain greatly limits the popularization and application of polycarboxylate water reducers in the field of concrete admixtures. It has been proved that the synthesis of complex functional group molecular structures with multiple functions can significantly improve the application performance of polymers. effect

Therefore, this requires the subversive innovation of the synthetic water reducer at the molecular structure level, not sticking to the traditional synthesis method, innovatively using high-valent cerium salts to trigger long chain polycations, depolymerization of cations and polyethers of alkenyl acid chloride alcohols The synthesis route and characteristics of the preparation of macromonomers and the copolymerization of large and small monomers to form a comb-shaped composite side chain structure, which not only has the composite performance of water-reducing and slump-resistant mud, but also is conducive to industrialization and application. The domestic work on this aspect is domestic There is no report outside

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