Silicone fireproof sealant for construction and preparation method thereof

The invention discloses a silicone fireproof sealant for construction and a preparation method thereof. The preparation comprises the steps of adding alpha, omega-dihydroxy polysiloxane, a filler, an inorganic flame retardant and a nitrogen system flame retardant into a kneading machine, carrying out dehydration at the temperature of 100-180 DEG C and the vacuum degree of 0.06-0.1MPa for 0.5-4 hours, cooling, and then preparing a base material. The base material, polydimethylsiloxane, an inorganic pigment, a crosslinking agent, a silane coupling agent and a catalyst are added into a planetary mixer at the room temperature, keeping the vacuum degree at 0.06-0.1MPa, stirring at the speed of 20-80 r/min, carrying out reaction under stirring for 0.5-6 hours, and preparing the silicone fireproof sealant for construction with no pollution to the base material, flame retardance and excellent adhesion and storage stability. The inorganic flame retardant and the nitrogen system flame retardant are in synergistic flame retardance, and the silicone fireproof sealant can effectively reduce the adding amount of the inorganic flame retardant and greatly improve the mechanical processing performance of a product under the situation of achieving the equivalent flame retardant grade FV-0.