Reactive polyurethane modified polyolefin hot melt adhesive and preparation method thereof

The invention discloses a reactive polyurethane modified polyolefin hot melt adhesive and a preparation method thereof, the reactive polyurethane modified polyolefin hot melt adhesive comprises a polyolefin hot melt adhesive component A and a polyolefin hot melt adhesive component B, and the mass ratio of the polyolefin hot melt adhesive component A to the polyolefin hot melt adhesive component B is (20-30): (70-80); the polyolefin hot melt adhesive component A is prepared from the following components in parts by mass: 10 to 25 parts of polyester polyol, 5 to 15 parts of first isocyanate and 5 to 15 parts of second diisocyanate; the activity of the first isocyanate is greater than that of the second isocyanate; the polyolefin hot melt adhesive component B is prepared from the following components in parts by mass: 40 to 65 parts of tackifying resin, 10 to 25 parts of thermoplastic elastomer and 0.1 to 0.2 part of catalyst. The isocyanate with different activities is compounded for use, and the thermoplastic