Polystyrene foam, as its name implies, is an adhesive with foaming and adhesive properties. It is mainly used for filling, sealing and bonding side seams of building doors and windows, expansion joints and holes of components. It is a moisture-cured polyurethane elastic sealing foam material. Polystyrene foam is composed of polyurethane prepolymer, foaming agent, catalyst and crosslinking agent. , packed in high-pressure resistant iron cans, and filled with propane and other gases. It is divided into gun type and tube type. The gun type can only be equipped with a special polyurethane foam gun, and the tube type can be equipped with a disposable hose.