What Is Silicone Injection Molding?
Silicone resin is a thermosetting polysiloxane polymer with a highly cross-linked structure. It has the dual characteristics of organic resins and inorganic materials. It has unique physical and chemical properties, good electrical insulation properties, temperature resistance and Waterproof effect.
- Silicone resin is a thermosetting polyorganosiloxane with a highly cross-linked structure. Due to its special structure, it has excellent heat resistance, cold resistance, weather resistance, electrical insulation, hydrophobicity, and resistance to other organic resins. Adhesive release, etc .; therefore, it is widely used as high and low temperature resistant insulating paint, heat resistant coating, weather resistant coating, ablation resistant coating, high and low temperature resistant, electrically insulating molding compound, etc. [1]
- Silicone resin types mainly include methylphenyl silicone resin, methyl silicone resin, low phenyl methyl silicone resin, silicone resin emulsion, self-drying silicone resin, high temperature silicone resin, epoxy modified silicone resin , Silicone polyester modified resin, self-drying environmentally friendly silicone resin, environmentally friendly silicone resin, non-stick coating silicone resin, high-gloss silicone resin, benzyl transparent silicone resin, methyl transparent
- Usually with
- Features
- Classification of silicone resins Silicone resins use silicon-oxygen-silicon as the main chain.
- The requirements for the mechanical properties of silicone resins mainly depend on the application. Silicone resins used as electrical insulating paints, coatings and adhesives are more concerned about their hardness, elasticity, thermoplasticity and adhesion. The hardness and elasticity of the silicone resin paint film can be changed within a wide range by adjusting the molecular structure of the resin. When the tri- or tetra-functional chain content is higher, that is, the larger the cross-linking density, a paint film with high hardness and low elasticity can be obtained; the introduction of substituents with large steric hindrance can improve flexibility and thermoelasticity. It is the reason why methylphenyl silicone resin is more flexible and thermoplastic than methyl silicone resin. Therefore, silicone resins do not need to use special plasticizers, but rely on the appropriate combination of soft and hard silicone resins to meet the plasticity requirements.
- When used as some coatings, the hardness of the pure silicone resin coating film is insufficient, while the thermoplasticity is more than enough; if an organically modified silicone resin is used, it is easy to resolve this contradiction.
- Pigments and catalysts can also affect the hardness and elasticity of silicone resins. Pigments have the effect of accelerating the oxidation of silicone paint films and transforming them into harder silica glass. With low-activity catalysts, only soft coatings can be obtained due to the incomplete condensation reaction. Conversely, with high-activity catalysts (such as compounds of Pb, Al, etc.), hard and brittle coatings can be obtained, but some catalysts (such as titanium Acid ester) can effectively improve the hardness of the coating without seriously reducing the elasticity.
- Silicone resin has good adhesion to iron, aluminum, silver, tin, glass, and ceramics, but it has poor adhesion to copper, especially after high temperature and long-term thermal aging, which may cause oxide films on other surfaces of copper. Accelerating the thermal cracking reaction of silicone resin. The adhesion of silicone grease to organic materials such as plastics and silicone rubber depends mainly on the surface energy of the latter and its compatibility with silicone resins. The lower the surface energy and the less compatible the material, the more difficult it is to adhere. By treating the surface of the substrate (including sanding and priming), especially by introducing a tackifier into the silicone resin, the adhesion of the silicone resin to difficult-to-stick substrates can be improved to a certain extent.
- Silicone resin is mainly used as
- Compared with silicone rubber and silicone oil, silicone resin is a less used product in silicone products, accounting for about 10% of silicone products. The world's total production of silicone resin is about 90,000 tons. The United States is the largest producer, about 40,000 tons. Except for domestic consumption of about 7,000 tons per year, the rest are exported. The output of Japan and Western Europe is basically the same, both are about 20,000 tons per year, and most of them are for personal use. It is estimated that in 2005, global consumption of silicone resin is expected to reach 100,000 tons.
- At present, there are nearly 20 domestic silicone resin production plants, of which nearly 10 are specialized paint or insulation material plants. The main products are insulation dipping varnishes, heat-resistant coatings, waterproof coatings, mica adhesives based on methyl and phenyl resins. Among them, the production scale of large-scale silicone resin devices is 1,000 tons, and the production scale of small-scale silicone resin devices is 100 tons.
- Compared with other organic silicon materials, silicone resin has been relatively stable in the domestic market for a long time. At present, the annual consumption of silicone resin in China is about 8,000 tons, which is mainly used in the electronics / electrical field. In recent years, China's high-end architectural exterior wall coating market has begun, of which, silicone-modified acrylic coatings (silicone-acrylic coatings) are important varieties. With the rapid development of high-end building exterior wall coatings in China, the consumption of silicone resin in the construction field will increase rapidly, and it will gradually replace electronics / electric appliances and become the main application area of silicone resin. It is expected that the domestic consumption of silicone resin in 2015 will reach 15,000 tons.