The biggest difference between polyurethane hot melt adhesive and hot melt adhesive is that polyurethane hot melt adhesive belongs to reactive hot melt adhesive. Hot melt adhesive not only has fast adhesion performance, but also can react with water or substrate in the air. After 3-5 days, the polyurethane resin with high strength, high elasticity, waterproof and temperature resistance is finally formed, and it will not melt after heating.