Silica gel is a kind of thermosetting elastomer. It has the advantages of safety and non-toxicity. It is insoluble in water and any solvents. Good stability and stable chemical properties. It was first widely used in adult products and food products.
As far as the surface is concerned, silica gel is a porous solid silica material with a large specific area. Silica gel is an amorphous substance and is a highly active adsorbent. Compared with other similar materials, silica gel has many advantages, such as high adsorption performance and stable chemical properties.
In terms of hardness, silica gel generally has a hardness of 0A to 70A, while TPE generally has a hardness of 0A-100A, the softest can reach 000 degrees or 00000 degrees, so TPE is softer, and the shape of silicone is stronger.
Silicone has advantages over TPE in terms of high temperature resistance. The temperature resistance of silica gel is generally between 200 ° C and 300 ° C, while TPE theoretically generally has a high temperature resistance between 130-150 ° C, and it will age and crack when it is higher.
Silicone has the following characteristics:
1. Both high temperature and cold resistance, can maintain good elasticity in the range of -100 degrees to -500 degrees.
2. Excellent resistance to ozone and weathering.
3. Excellent electrical insulation.
4, with hydrophobic surface characteristics and physiological inertia, harmless to the human body.
5, with high air permeability, more than 10-100 times larger than ordinary rubber.
Divided into two types according to the physical state of silica gel: solid and liquid
Characteristics of liquid silicone
Liquid silicone is generally used in baby products, kitchen supplies, and medical supplies. It can directly contact food and the human body.
Liquid silicone has good transparency, tear resistance, resilience, yellowing resistance, thermal stability, water resistance, good air permeability, heat aging resistance and weather resistance. At the same time, the viscosity is moderate and easy to handle.
Due to the superior properties of liquid silicone, it is now widely used in people's daily life in the clothing and silk printing industry (various fabric printing, professional swimwear, swimming caps, etc.), household items (furniture, baby products, etc.), transportation (car interior decoration, Yachts, etc.)
Features of solid silicone
Generally used in daily necessities, industrial miscellaneous parts, and automotive parts.
Solid silica gel is industrially based on water glass (sodium silicate) as a raw material, hydrolyzed to form a gel in an acidic medium, and then made into silica gel by aging, washing, drying and other processes. Depending on the water content, it is translucent or white solid. Commercially available products include irregular granular, spherical, and microspherical silica gels, which are often used as catalyst carriers in fluidized bed operations.
Reasonable selection of materials needs to be considered from the product's environment and the properties of the materials. The main properties of soft rubber products are: hardness, elasticity, corrosion resistance, weather resistance, friction coefficient, whether it is crackable, coloring properties, high resistance ) Temperature performance, cost, processing technology, etc. If it is used in daily necessities, baby products, etc., you need to pay attention to whether the material is harmful to the human body, whether it has an unpleasant smell, and whether it feels comfortable. Special circumstances also need to consider the conductive properties (such as silicone keypad can be made when conductive carbon black is added), thermal conductivity, radiation resistance, light transmission performance, and so on.