The hardness of liquid silicone is generally adjusted according to the needs of the application, but some users find that the hardness of the silicone mold made is too high. This situation usually occurs in inexperienced new users, so if you encounter this problem, how to solve it Well, the following Hongye silica gel manufacturers provide two methods to reduce the hardness.
Experienced liquid silicone users will know that there is a certain error range between the actual hardness of the silica gel purchased and the data you provide to the manufacturer. This error is generally around ±2 Shore A. Especially for novices who are uncertain about the hardness they need, this will cause greater hardness errors.
By the former method: we can use silicone oil to reduce the hardness of the silicone. Generally, adding 1% silicone oil will reduce the hardness of the silicone by about 0.9-1.1 degrees; adding 10% silicone oil will reduce the hardness of the silicone by about 5 degrees. However, in actual operation, if the added silicone oil ratio is too high, it will destroy the molecular weight of the silicone rubber, and the tear resistance and tensile strength will be correspondingly deteriorated, which will affect the service life of the silicone mold. In addition, adding too much silicone oil will also cause the silicone rubber mold. easily transformed. Therefore, we suggest: Generally, the ratio of silicone to silicone oil should not exceed 5%, and try to add silicone oil with a higher viscosity. If you add silicone oil with more than 5%, please try a small amount to determine whether the mold made can be used.
The second method: use high-hardness silica gel and low-hardness silica gel. The premise of using this method is that you have purchased two kinds of hardness silica gel, such as 20-hardness silica gel and 10-hardness silica gel. The hardness of the silica gel is 15 Shore A after mixing. about. When using this mixing method, it should be noted that the condensation type cannot be mixed with the addition type, otherwise it will cause non-curing.