There are many methods for vulcanizing silicone products, each of which has its own unique features and scope of application. The following are several common methods for vulcanizing silicone products and their differences:
1. Hot air vulcanization method
Features: Hot air vulcanization under normal pressure is the most commonly used vulcanization method for preparing pipes and profiles.
Differences: By introducing hot air, not only can volatile combustibles be removed, but also the vulcanization speed can be promoted. This method is suitable for products that require a longer vulcanization time or larger size.
2. Continuous steam vulcanization method
Features: The extruder head is directly connected to the steam vulcanization telescopic sleeve, which is filled with steam pressure, and the extruded silicone products are directly vulcanized in high-pressure steam.
Differences: This method uses high-pressure steam for vulcanization, and the vulcanization speed is faster. It is suitable for occasions where silicone products are continuously produced, such as extruded silicone tubes.
3. Hot solution vulcanization method
Features: The silicone product is placed in a heat carrier composed of alkali metal nitric acid and polyethylene glycol containing an antioxidant for vulcanization, and then the heat carrier adsorbed on the surface of the silicone product is washed away.
Difference: The vulcanization speed is several times faster than the hot air vulcanization method, but it may cause problems such as discoloration of silicone products. This method is suitable for products with high requirements for vulcanization speed.
4. Fluidized bed vulcanization
Features: Silicone products are vulcanized through a fluidized bed.
Difference: The vulcanization speed is more than 2 times faster than the hot air vulcanization method, but it is difficult to remove the glass microspheres from the surface of silicone products, which may make the products appear rough. This method is suitable for products with high requirements for vulcanization speed and low requirements for surface roughness.
5. Ultra-high frequency vulcanization method
Features: The conductive characteristics of silicone rubber itself are used to generate heat to achieve vulcanization.
Difference: The vulcanization process is relatively uniform and is suitable for products that require uniform vulcanization. This method does not require an external heat source and is energy-saving and efficient.
6. Room temperature vulcanization method
Features: Vulcanization is carried out at room temperature and pressure, such as using room temperature vulcanization glue for seams and repairs.
Difference: The vulcanization process is simple and convenient, and does not require complex equipment and high temperature environment. Suitable for small products or repair work.
7. Mixed air vulcanization method
Features: First use air vulcanization, then use steam direct vulcanization.
Differences: Combining the advantages of air vulcanization and steam vulcanization, it can overcome the shortcomings of steam vulcanization affecting the appearance of the product, and overcome the shortcomings of slow heat transfer of hot air, long vulcanization time, and easy aging. It is suitable for products with high requirements for vulcanization effect and appearance.
In summary, the vulcanization methods of silicone products have their own unique features and scope of application. In actual production, the appropriate vulcanization method should be selected according to the specific requirements of the product, production conditions and cost considerations.
