The hardness of silica gel is the same as that of ordinary rubber, which is distinguished by Shore hardness. Generally, the higher the degree, the harder the hardness. At present, the hardness of silicone raw materials can reach 0-90 degrees. Silicone raw materials are divided into solid silica gel and liquid silica gel. The hardness of solid silica gel (mixed silicone rubber) can reach 20-90 degrees, and the commonly used one is 30-70 degrees. And if you want to need silicone raw materials with lower hardness, you need to use liquid silica gel. The hardness of liquid silica gel is 0-20 degrees, and the commonly used one is 10-20 degrees. So will the hardness of silicone products change after molding? Will the hardness of silicone products change?


Some friends also asked whether the hardness will harden when the silicone is molded? Of course not, the hardness of the molded silicone product is the same as that of the silicone raw material, so don't worry.

The hardness of silica gel is generally adjusted. The hardness has little to do with the temperature. The temperature is only related to the curing time. Hongtu Silicone Tips: Low temperature cures slowly, high temperature cures quickly

What are the effects of different hardness of silicone products:

1. Changes in extrusion strength. Low-hardness products will gradually decrease in strength, while high-hardness products will increase. A difference of 5-10 degrees will have different extrusion changes.

2. Changes in tear resistance, the higher the hardness, the weaker the tear resistance of the product, especially products with right angles are prone to tearing, the lower the hardness, the better the tear resistance, and the different hardness is different.

3. The constant elongation stress leads to deformation. The constant elongation stress is an important control index of the silicone material, which has a certain relationship with the hardness. Different hardness and the temperature and pressure controlled during the vulcanization process are important for the deformation of the product. Relationship.

4. Changes in wear resistance and fatigue. Products with different hardness have different effects on wear resistance and fatigue. Generally, the hardness of silica gel material increases with the increase of crystallinity, and long-term running-in will affect the decrease of fatigue. The wear resistance is not enough Phenomenon.

5. The elasticity is different. Elasticity is one of the important elements in the silicone material, so materials with different hardness have an impact on each product with different applications, and the large difference in hardness may lead to the use effect of the entire product, and even affect the quality of the product. Every link of a whole!

Generally, the process can be changed, and mold silicone manufacturers can change the hardness of the product according to the process. On the material side, various intermediate hardness values can be achieved by mixing different ratios of polymer base, filler and additives. In terms of technology, the time and temperature of heating and curing can also change the hardness without destroying other physical characteristics.


About silicone rubber, please check the details:
https://www.siliconefoam.net/product-soft-cellular-silicone-iota-ht-870-.html