Experimental principle of foam plastics forming

　　The diisocyanate, polyether and water, polyester and catalyst were added to the foam tank of the medical foaming machine according to the ratio. After heating and mixing, the materials in the mixing head were put into the carton. After 0.5-3min foaming, it was put into the oven and was cooked at 1H at 100 degrees. The oven was cooled out to the room temperature and the polyurethane foam was obtained.

　　Polyurethane foam is a new type of polymer composite material. Compared with other foam, it has many characteristics in performance. Besides small density, it has many characteristics, such as odorless, breathable, uniform bubble, humidity resistance, aging resistance, organic solvent corrosion resistance, and so it has broad application prospects.

　　Polyurethane foam molding is more complex than any other polyurethane molding. Besides the physical state change of the Warsaw guest in the polymer reaction, the foam formation is increased. Characteristics of frontal colloidal chemistry. To understand the formation of polyurethane foam, polymer chemistry, nucleation process and colloid chemistry of foam, as well as rheology of polymerization system during maturation, are also involved.

　　The manufacture of flexible polyurethane foam is divided into three processes: prepolymer method, semi prepolymer method and one-step process.