Manual batch method

This method is a more commonly used method in laboratory and batch production. The commonly used oligomer polyol/TDI/MOCA system operation process is to weigh an appropriate amount of prepolymer in a container of appropriate size, heat it to 80-90°C under stirring, and place it in a vacuum dryer to degas 5～ 20min, then add melted MOCA and other chain extenders, stir and mix evenly (1～2min), if necessary, perform secondary defoaming (2～3min), then pour into the prepared mold, heat to vulcanize or wait for gel When molding and curing. For large products, mixing and degassing in the reactor can be used, and then pouring and forming. The advantage of this method is less investment, but the disadvantage is that the rubber has high viscosity, short pouring time, easy to entrain bubbles, difficult to mix uniformly, low production efficiency, high labor intensity, and it is only suitable for small-scale production of small and medium-sized products.

Mechanical continuous method

This method uses the casting machine as the main equipment. The preheating and defoaming of the prepolymer, the melting of the chain extender (such as MOCA), and the metering, mixing and pouring of the prepolymer and the chain extender are all in the casting machine. Continuous completion. The operation of heating, metering, mixing, pouring, cleaning and stopping driving of materials can also be automatically controlled by the computer, which can continuously produce CPU products. This method is widely used in the polyurethane industry. Its advantages are stable product quality and high production efficiency, suitable for the production of large and medium-sized products and mass products. The production device is shown in the figure.