Polycarboxylic acid water reducing agent with excellent rust resisting function and preparation method thereof

Abstract

The invention relates to a polycarboxylic acid water reducing agent with an excellent rust resisting function and a preparation method thereof, belonging to the technical field of concrete water reducing agents. The preparation method comprises the following steps of: (1) esterification reaction, i.e. using a 98% concentrated sulfuric acid as a catalyst, sequentially adding polyethylene glycol monomethyl ether, acrylic acid, sodium benzoate and benzotriazole, carrying out the esterification reaction for 4 hours under a sealing condition at 110-120 DEG C so as to obtain a mixture of a polyethylene glycol triazole-group acrylic acid esterified compound and the rest acrylic acid; (2) copolymerization reaction, i.e. using ammonium persulfate as an initiator, and directly copolymerizing the mixture of the polyethylene glycol triazole-base acrylic acid esterified compound and the rest acrylic acid, which is obtained in the step (1), for 3 hours at 90+ / -5 DEG C so as to obtain the polycarboxylic acid water reducing agent with a rust resisting group. The invention has the advantages that a polymerization inhibitor does not need to be added any more during the esterification reaction, the catalyst can be finally converted into a part of the water reducing agent; a polymerization-inhibiting functional group triazole-group is directly led during the esterification reaction, thereby product structures are controller and the requirements of product properties are met; more inexpensive acrylic acid is used as a raw material, thereby being beneficial to reducing the cost of the polycarboxylic acid water reducing agent; and in addition, the invention has relatively simpler process and moderate reaction condition and is easy for mass production.

Description

technical field [0001] The invention belongs to a concrete water reducer for construction engineering materials, in particular to the design and preparation method of a polycarboxylate water reducer with excellent antirust function for high performance concrete. Background technique [0002] At present, concrete water reducers at home and abroad are mainly divided into three series: one is lignosulfonate water reducer, the other is sulfonated aromatic polymer water reducer, and the third is polycarboxylate water reducer. Polycarboxylate superplasticizer belongs to the third generation of superplasticizer, which has high water reducing rate, less dosage, suitable for preparing high-performance concrete such as high fluidity and self-compacting. Because the raw materials used have little impact on the environment, the synthesis process is relatively environmentally friendly , basically non-polluting, is considered to be the best type of concrete water reducing agent. [0003]...

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Problems solved by technology

[0004] For anti-rust products used in concrete, they are mainly composite methods, such as patent application number 200610044239.4 named "a reinforced concrete rust inhibitor", and patent application number 200910008272.5 named "concrete anti-corrosion rust inhibitor" Anti-seepage agent", these products have basically no water-reducing function, and their application is limited. Generally, they cannot be used alone in concrete applications.

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