What are the polyurethane rigid foam foaming processes? We are going to take you to understand the polyurethane rigid foam foaming process.

  1.Prepolymer method

  The foaming process of prepolymer is that (a) and (b) prepolymer are made into prepolymer, and then water, catalyst, surfactant and other additives are mixed into prepolymer under high speed stirring.

  2.dimer and semi prepolymer method

      The foaming process of semi polymer method is to prepare polyether polyol (A material) and two cyanate ester (B material) into prepolymer, then add polyether or polyester polyol and two cyanate ester, water, catalyst, surfactant and other additives, and mix it into foam at high speed.

       3. One step foaming process

        step by step, add polyether or polyester polyol (raw material) and isocyanate (raw material b), water, catalyst, surfactant, foaming agent, other additives and other raw materials, and conduct foaming after high-speed mixing.

   one step foaming process is the most widely used polyurethane foaming process at present. There is also manual foaming, which is the simplest method. After all the raw materials are accurately weighed, they are put into the container, and then the raw materials are immediately mixed evenly and put into the mold or the space to be filled. Note: the polyisocyanate (black) must be weighed at last.

  Rigid polyurethane foam is usually foaming at room temperature, and the molding process is relatively simple. According to the degree of construction mechanization, it can be divided into artificial foaming and mechanical foaming; according to the foaming pressure, it can be divided into high pressure foaming and low pressure foaming; according to the molding method, it can be divided into pouring foaming and spraying foaming.