The invention discloses a single-component
polyurethane grouting material foamed when meeting water, and a preparation method and an application thereof. The invention provides the preparation method for the single-component
polyurethane grouting material foamed when meeting water, wherein the preparation method comprises the following steps: step 1, carrying out a
polymerization reaction of hydrophilic polyether
polyol and an organic polyisocyanate compound, to obtain a
polyurethane prepolymer, wherein the hydrophilic polyether
polyol has the functionality degree of 3-4 and the number-average molecular weight of 5000-7000; and step 2, stirring and mixing the polyurethane
prepolymer obtained in the step 1 with an organic cosolvent, a surfactant, a catalyst and a
plasticizer, to obtain the single-component polyurethane grouting material foamed when meeting water. The polyurethane grouting material forms elastic foams after being reacted when meeting water, after water is volatilized, the polyurethane grouting material is naturally shrunk to a certain extent, the foam bodies are still intact, the polyurethane grouting material can absorb water to swell when meeting water again, and a secondary water plugging effect is achieved; therefore, the polyurethane grouting material can rapidly plug water, is foamed when meeting water, and has good cohesiveness and good marketization prospects.