So what is the hardness of all kinds of silicone products? What is the difference in hardness of different silicone products? What is the hardness standard of silicone products?
Hardness standard of silicone products:
Generally, for the products with large elasticity or soft feel, testers can directly determine the use of Shore HA hardness tester, such as: stationery plastic water bottle, TPUTPR plastic film bag and other products. And feel basic little elasticity or hard can be used to test Shore HD hardness tester, such as: PCABSPP and other products. If the degree is Shore xxHA, the hardness is relatively low. If it is Shore xxHD, the hardness is relatively high.
What are the differences in hardness of various silicone products?
According to the use of various fields to choose different hardness of silicone products, Mix low hardness can do about 10 degrees, special silicone products can reach about 280 degrees! The commonly used silicone products are between 30 degrees and 70 degrees.
There is also ordinary silicone products, can not be done with liquid silicone technology, there will be problems such as: silicone products are not good self-disassembly, the material is different, which leads to a problem is that the raw edge of the product is not smooth, the appearance of burr. So liquid silicone is suitable for low degrees of silicone products.
The other is the ordinary silica gel process, that is, the solid silica gel product process. At present, the whole silica gel industry internal solid silica gel product process can do the low softness is 30 degrees, the max height is 80 degrees, although higher degrees can also be done, but the defect rate is too high, the product is brittle, and it is not good to self-disassembly. So solid state technology is most suitable for soft and hard degrees between 30 degrees and 70 degrees. Can not do more soft products, but self-disassembly better, the product appearance is beautiful, no burr.
The hardness of silica gel and ordinary rubber is the same, Shore hardness is used to distinguish, generally the higher the hardness is harder, the hardness of silica gel raw materials can reach 0 degrees -90 degrees. Silica gel raw materials are divided into solid silicone and liquid silicone, solid silicone (mixed silicone) hardness can reach 20 degrees -90 degrees, commonly used for 30 degrees -70 degrees. And if you want to demand lower hardness of silicone raw materials, it will need to use liquid silicone, liquid silicone hardness is 0 degrees -20 degrees, commonly used for 10-20 degrees.
In general, we use the most contact with the most widely is solid silica gel (mixed silica gel), in processing molding is more commonly used in the hardness of 30 degrees -70 degrees, if there are special needs of solid silica gel hardness can reach 20 degrees, the hardest can reach 90 degrees, but the lower the hardness of the molding process is more difficult.
And silicone hardness if reached 80 degrees -90 degrees, in the mixing process is more difficult, the use of machinery and equipment is not the same. And high hardness silicone raw materials in molding scrap rate is very high, the product is very brittle, not good self-disassembly. Therefore, if you want to produce silicone products, the most appropriate hardness should be between 30 degrees -70 degrees.
Different hardness of silicone products will bring what aspects of the impact:
1, the change of extrusion strength, low hardness products will gradually decrease in strength, high hardness will increase, 5-10 degrees of difference will have different extrusion changes.
2, the change of tear resistance, the higher the hardness of the product tear resistance will be weaker, especially with the right Angle of the product is easy to tear, the lower the hardness of tear, the better the hardness is different.
3. Constant elongation stress causes deformation. Constant elongation stress is an important control index of silicone material, which is precisely related to hardness.
4, the change of wear and fatigue, different hardness of products have different effects on wear and fatigue, generally silica gel material with the increase of crystallinity hardness increases, long-term run-in will affect the phenomenon of fatigue decline wear-resistant enough.
5, the difference of elasticity, elasticity is one of the important elements in the silicone material, so the material of different hardness has an impact on each different application of the product, and the hardness of the ± difference is too large may lead to the use of the whole product, and even affect each link of the whole!
