The invention discloses a hyperbranched water
reducing agent for high-tensile wet joint UHPC (
Ultra High Performance Concrete) as well as a preparation method and application of the hyperbranched water
reducing agent, and belongs to the technical field of concrete admixtures. The preparation method comprises the following steps: mixing
pentaerythritol and
maleic anhydride, adding a catalyst p-toluenesulfonic acid, and carrying out an
esterification reaction to prepare an esterification product; carrying out amidation reaction on the esterification product, diethanol amine and a catalyst
sodium ethoxide to obtain a
prepolymer;
acrylic acid,
maleic anhydride and the
prepolymer are dissolved in deionized water, an initiator
ammonium persulfate is added for a free radical copolymerization reaction, and a main chain
polymer is obtained; carrying out
phosphorylation reaction on the main chain
polymer and
phosphorus pentoxide to obtain a phosphorylated main chain
polymer; the phosphorylated main chain polymer,
methoxypolyethylene glycol and a catalyst p-toluenesulfonic acid are subjected to an etherification reaction, a hyperbranched comb-shaped polymer water
reducing agent solution is obtained and then subjected to aftertreatment, and the water reducing agent is prepared. According to the hyperbranched comb-shaped polymer water reducing agent prepared by the preparation method disclosed by the invention, the problems of poor flowability and high
viscosity of ultra-
high performance concrete (UHPC) are solved by combining a linear
side chain of a comb-shaped structure and a three-dimensional
branch of hyperbranched topology.