Polyurethane blowing agent: It is a special polyurethane product, which is the product of the cross-combination of aerosol technology and polyurethane foam technology. This blowing agent is usually filled in a pressure-resistant aerosol can, and when the material is ejected from the aerosol can, the foam-like polyurethane material expands rapidly and reacts with the moisture in the air or the substrate it comes into contact with, forming a foam. Polyurethane foaming agent has the advantages of pre-foaming, high expansion, small shrinkage, etc., and the strength of the foam is good, the adhesion is high, and the cured foam has a variety of effects such as caulking, bonding, sealing, heat insulation, sound absorption, etc., which is an environmentally friendly and energy-saving, easy-to-use building material.