| abstract |
Embodiments of the present invention relate to the technical field of concrete admixtures, and provide a phosphonato block polymer, a preparation method therefor and an application thereof. The method comprises: the phosphonato block polymer is prepared by copolycondensating an ether-type segment A, a phosphonato segment B, and a third part of aldehyde C. The molar ratio of the ether-type segment A to the phosphonato segment B is 1:(0.8-5.0). The ether-type segment A is obtained by polycondensating a polyether monomer a having a particular structure and a first part of aldehyde C. The molecular weight of the polyether monomer a is 1,200-4,800, and is preferably 1,500-2,500. The phosphonato segment B is obtained by polycondensating a monomer b containing phosphonato and having a particular structure, a monomer c, and a second part of aldehyde C in an aprotic weak polar solvent E. By preparing a block polymer using arylalkane as a main chain and using a phosphonic acid or phosphinic acid functional group as an adsorption group, the present invention improves the resistance of the block polymer to sulfate and clay interference, and can achieve the purpose of the initial high dispersion of concrete with a low water-cement ratio and decreasing of the system viscosity. |