The use of silicone oil in polyurethane foaming machine has the following advantages:
1. Reducing the surface tension is conducive to the production of uniform microbubbles and stable cells to reduce gas diffusion.
2. Increasing the viscosity of the material faster helps to slow down the rapid thinning and foaming of the cells.
3. Increase the strength of the cell membrane wall and cell meridian.
4. Reduce the mixing of impurities to avoid foam collapse and voids caused by the decrease of local surface tension of the cells.
5. When the amount of silicone oil is low, the foam with larger pore size is unstable. When the dosage is higher, the pore size becomes smaller and the surface area of the foam increases. If the amount is too much, the bubble will collapse when it reaches a high point. The reason is that the bubble wall is too thin and the support strength is insufficient.
In addition, the production process of silicone oil is very complicated and strict. Different formulas, different processing conditions and production methods make the final products very different. That is to say, different silicone oils may directly affect the quality of polyurethane foaming machine products, including: appearance, feel, hardness, and tensile strength.
Using too much or too little silicone oil will affect the quality of the foam;
High dosage: increase the elasticity of the foam wall in the later stage, not to break, and the cells are fine. Cause closed cells.
Low dosage: Too little amount of silicone oil will result in insufficient foam stability, serious coalescence, large and uneven cells, or even collapse.