Slow-release type polycarboxylic water reducing agent, preparation method thereof and application

The invention belongs to the technical field of a concrete admixture in building materials and provides a slow-release type polycarboxylic water reducing agent, a preparation method thereof and application. The slow-release type polycarboxylic water reducing agent is synthesized by adopting a free-radical polymerization method in an aqueous solution. The slow-release type polycarboxylic water reducing agent is prepared by unsaturated polyoxyethylene ether, unsaturated acid or a mixture of unsaturated acid ester and the unsaturated acid, a chain transferring agent, an oxidizing agent, a reducing agent and water. The slow-release type polycarboxylic water reducing agent has the advantages of low doping amount, good plasticity-maintaining effect, good cement adaptability and good energy-saving and environmental-friendly effects and the like; the production process is simple; the equipment investment is less and the cost is low; by the adoption of the water reducing agent, water reducing components can be gradually released, and the content of the effective water reducing components in the concrete is guaranteed, and the plasticity of the concrete is maintained, and the cement hydration can be delayed, further the maintaining capability for the slump and the fluidity is excellent for concrete with large slump and concrete with medium and small slump respectively, and the large-volume concrete cracks generated by over-high hydration temperature can be reduced, and the mixability and the mechanical property of the concrete can be improved.