The formula of neutral room temperature vulcanized silicone rubber mainly includes the following ingredients and their functions:
Terminated hydroxyl polymerized dimethylsiloxane SF-BQ200: As the main ingredient, it provides the basic properties of silicone rubber.
Methyl trisbutyl ketoxime silane SF-SMOS: As a crosslinking agent, it promotes the curing reaction of silicone rubber.
Fumed silica: As a reinforcing filler, it improves the mechanical strength and wear resistance of silicone rubber.
Calcium carbonate: Increases the hardness and stability of silicone rubber.
Silane coupling agent: Such as SF-S550, it enhances the bonding strength between the filler and the silicone rubber matrix.
Dibutyltin dilaurate SF-DBTDL: As a catalyst, it accelerates the curing reaction.
Dye: Used to adjust the color of silicone rubber.
Specific formula example:
One-component deoxime type room temperature RTV silicone rubber formula:
Terminated hydroxyl polymerized dimethylsiloxane: 100 parts
201 silicone oil: 32 parts
Methyl tributyl ketone oxime silane SF-SMOS: 7~9 parts
Fumed silica: 8 parts
Calcium carbonate: 45~55 parts
Silane coupling agent SF-S550: 2 parts
Dibutyltin dilaurate SF-DBTDL: trace amount
Dye: appropriate amount
Two-component room temperature RTV silicone rubber formula:
Component A ... Dimethylsiloxane: 100 parts
Ultrafine calcium carbonate: 40~50 parts
Fumed silica: 9~10 parts
Titanium dioxide: 5 parts
Component B:
Ethyl orthosilicate: 7~8 parts
Butyl borate: 3~4 parts
Butyl titanate: 3~4 parts
Dibutyltin dilaurate: trace amount
Preparation method: Mix the components evenly according to the formula ratio, prepare the mixed rubber by mixing or mixing process, and then vulcanize at room temperature to form elastic vulcanized rubber.
Application field: Neutral room temperature vulcanized silicone rubber is widely used in electronics, light industry, machinery, construction, chemical industry and other industries as bonding, sealing, insulation, moisture-proof and shock-proof materials, especially suitable for electronic components, semiconductor materials, electric heaters, waterproofing, sealing of electronic instruments and potting of electronic components, etc.