Molding process is the production process of solid silica gel, with the upper and lower two modules combination, placed in the middle of a mold core, so it is called molded silicone rubber. The main production process of molded silicone rubber products is the silicon rubber processing process which is formed by heating and pressurizing the silicon rubber raw materials in the closed mold cavity. Usually raw materials are evenly stirred by the mixing machine into the mixing glue, and then the mold is transferred into the vulcanization molding machine. Then close the mold pressure, molding and curing or vulcanization, and then demoulding silicone products, this process is suitable for thermosetting materials processing。

The advantages of molded silica gel products

1. Can be made into any shape
2. High precision, beautiful commodity shape rules
3. The colors are bright and can be mixed at will

Disadvantages of molded silica gel products

1. Limited product size
2. There will be a lot of rough edges and waste products in the production process
3. The cost of mold is relatively high and the development cycle is long

Problems that should be paid attention to in molding

1. When silicone products are molded, silicone rubber is pressed under high pressure, and the cohesion of the elastomer cannot be eliminated. When silicone rubber is molded, it often produces extremely unstable shrinkage (the shrinkage rate of silica gel is different due to different types of rubber). Therefore, at the beginning of the design of silica gel products, regardless of formula or mold, need to be carefully calculated with comprehensive consideration, otherwise it is easy to produce silica gel products size instability, resulting in product quality decline.

2. Silica gel is a thermosetting elastomer, plastic is a thermosetting cold solid. Silica gel due to different types of silica gel vulcanization agent, its molding curing temperature range, there is a considerable gap, even silicone rubber vulcanization can be affected by climate change, indoor temperature and humidity. Therefore, the production conditions of silica gel products need to be adjusted moderately at any time, otherwise, the quality of products may be different.

3. Silica gel products are made of silica gel raw materials made of silicone rubber mixing machine after mixing as raw materials. In the mixing process, the formula is designed according to the characteristics of the required silicone rubber products, and the required product hardness and the type of silicone rubber vulcanization agent are determined. Silicone rubber products made by rubber plate vulcanizing machine for molding. After the product is formed, the final edge treatment is carried out to smooth the surface of the product without burr.

4. Problems such as sticking mold, warping edge, air bubbles, incomplete curing white point and so on will occur in the process of silicone rubber mold pressing and vulcanizing. It is necessary to adjust the mold temperature, exhaust time and mold pressure.