How to calculate the shrinkage rate of liquid silicone mold?

The shrinkage rate of a silicone mold depends on many factors, including the hardness of the silicone, the structure of the mold, the size and shape of the mold cavity, the thickness of the silicone, etc. Generally speaking, the shrinkage rate of silicone molds is usually between 0.5% and 2%.
Specifically, if the hardness of the silicone mold is higher, its shrinkage will usually be lower. This is because the molecules of silica gel with high hardness are arranged more tightly and are therefore less prone to deformation. On the contrary, if the hardness of the silicone mold is lower, its shrinkage will usually be higher. This is because the molecules of silica gel with low hardness are loosely arranged and therefore prone to deformation.
 
In addition, the structure of the mold and the size and shape of the mold cavity will also affect the shrinkage rate of the silicone mold. For example, if the structure of the mold is relatively complex, the silicone will experience greater resistance when filling the mold and will therefore be prone to deformation. In addition, if the size and shape of the mold cavity are different, the silicone will also be subject to different pressures and stresses when filling the mold, thus affecting its shrinkage rate.
 
Therefore, to determine the shrinkage rate of a silicone mold, multiple factors need to be considered and need to be determined through experiments or empirical values. Normally, the shrinkage rate of silicone molds can be calculated by the following formula:
 
Shrinkage = (mold size - silicone size) / silicone size
 
Among them, the mold size refers to the size of the mold at room temperature, and the silicone size refers to the size of the silicone at room temperature. By measuring these two dimensions, the shrinkage rate of the silicone mold can be calculated.

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