Water-based microporous polyurethane film and preparation method thereof

The invention relates to the technical field of urethane films, and discloses a water-based microporous polyurethane film, which is prepared from the following raw materials in parts by weight: 80 to 100 parts of polyurethane, 6 to 10 parts of cross-linking agent, 7 to 9 parts of flatting agent, 1 to 3 parts of flatting agent, 1 to 2 parts of plasticizer, 2 to 3 parts of weather-resistant agent, 40 to 60 parts of calcium carbonate, 100 to 120 parts of deionized water and 10 to 30 parts of flame-retardant resin. According to the water-based microporous polyurethane film and the preparation method thereof, during production, polyurethane and calcium carbonate are blended, after extrusion film forming, the film is formed by directional stretching at a certain rate, as polyurethane is a thermoplastic material and can be stretched and crystallized under a certain condition, and during stretching, interface stripping occurs between a polymer and calcium carbonate particles, so that the water-based microporous polyu