How to vacuum liquid silicone? Firstly, we need to understand why liquid silicone needs to be vacuumed? What is the purpose of vacuuming?
Liquid silicone is generally composed of two-component materials, with component A being silicone and component B being a curing agent. The two are stirred evenly in a certain proportion before curing. Liquid silicone itself contains a certain viscosity. Silicone with high viscosity can generally reach around 20000 to 30000 yuan, while silicone with low viscosity can also reach around 2000 to 3000 yuan. However, regardless of whether the viscosity is high or low, as long as the two components of liquid silicone are stirred together, bubbles will be generated.
Many people may think that liquid silicone will self defoaming, but in fact, the so-called self defoaming silicone is achieved by reducing the viscosity of silicone, prolonging the operation time, and allowing enough time for the bubbles inside the liquid silicone to be discharged. However, to achieve 100% of the bubbles to be completely discharged, it is necessary to use a vacuum machine equipment to extract the bubbles through mechanical external force. So how does liquid silicone vacuum?
When using a vacuum machine to exhaust bubbles, the first step is to choose a vacuum machine with an appropriate power size, because the amount of silicone gel used for each customer's single bubble is different, with varying degrees. Under normal circumstances, it is recommended to choose a power range of 2-3 kilowatts for use. The container for storing silicone must be large, and each time the silicone is poured in, only one-third of the container must be filled, leaving enough space for the silicone bubbles to slowly rise and discharge. If the pressure pointer of the empty box turns below -0.1MPA, it indicates that the bubbles inside the silicone have been almost completely drained. When vacuuming, it is important to observe and repeat the process several times. The total vacuuming time should be around 2 minutes.
After vacuuming, the silicone can start pouring directly into the mold frame. After using the vacuum machine to solidify the silicone, there are no pores on the inside or outside of the mold, and the curing is quite tight. The service life of the mold is also quite long.
