MULTITYPE-ADSORPTIVE-GROUP POLYCARBOXYLIC ACID WATER-REDUCING AGENT, METHOD FOR PREPARING THE SAME AND USE THEREOF

摘要

The present invention discloses a multitype-adsorptive-group polycarboxylic acid water-reducing agent, consisting of 30-60 wt % of a macromolecule with multitype-adsorptive groups and water, the macromolecule with multitype-adsorptive groups has a polyethylene glycol side chain, and adsorption groups of the polymer backbone include a carboxylic acid group, a sulfonic acid group and a phosphoric acid group, the phosphoric acid group being linked to the backbone of the macromolecule with multitype-adsorptive groups by nucleophilic addition. The water-reducing agent of the present invention has significantly improved adaptability to different cements and aggregates while maintaining a high water reduction efficiency, compared with the conventional polycarboxylic acid water-reducing agent. It has a good water reducing efficiency in many different grades of cement, as well as a better resistance to aggregates containing more impurities such as machine-made sand.