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　　Prepolymer foaming process is (white) and (black) first made into a prepolymer, and then in the prepolymer add water, catalyst, surfactant, other additives mixed in high-speed mixing foam, curing at a certain temperature can be cooked.

　　The foaming process of semi-prepolymer method is to make some polyether polyols (white materials) and diisocyanate (black materials) into a prepolymer, and then add another part of polyether or polyester polyols and diisocyanate, water, catalyst, surfactant, other additives and so on, and mix to foam under high-speed agitation.

　　In one-step foaming process, raw materials such as polyether or polyester polyol (white material) and polyisocyanate (black material), water, catalyst, surfactant, foaming agent and other additives are added in one step, which are mixed at high speed for foaming.

　　One - step foaming process is commonly used. There is also the manual foaming method, which is the easiest method. After all the raw materials are accurately weighed, they are placed in a container, and then they are immediately mixed and injected into the mold or the space needed to fill the foam. Note: be sure to weigh the polyisocyanate (black) at the end.

　　Polyurethane foaming agentGenerally for room temperature foam, molding process is relatively simple. According to the degree of construction mechanization can be divided into manual foaming and mechanical foaming; According to the foaming pressure can be divided into high pressure foaming and low pressure foaming; According to the molding mode can be divided into pouring foam and spraying foam.