Polyurethane caulk compound for high-speed railway and preparation method for polyurethane caulk compound

The invention discloses a polyurethane caulk compound for a high-speed railway and a preparation method for the polyurethane caulk compound. The weather resistance and the low-temperature resistance of a product are higher than those of a conventional polyurethane caulk compound, and the normal service life of the product can reach more than 15 years, and the product can be widely applied to a concrete roadbed slab of a roadbed of the high-speed railway and other concrete roads and structures. The polyurethane caulk compound for the high-speed railway comprises a component A and a component B, wherein the component A comprises the following components in parts by mass: 60 to 70 parts of low-unsaturation high-molecular weight polyol and 30 to 40 parts of aromatic isocyanate; the component B comprises the following components in parts by mass: 100 parts of low-unsaturation high-molecular weight polyol, 3 to 5 parts of a polyhydroxy fluorinated polymer, 50 to 150 parts of a filler, 3 to 5 parts of a chain extender and 0.5 to 1.0 part of a catalyst; and when the polyurethane caulk compound is used, the mass ratio of the component A to the component B is (1 to 1.0 ) to (1 to 4.0).