Analysis of Neutral Room Temperature Vulcanizing Silicone Rubber Formulation
The formulation of neutral room temperature vulcanizing silicone rubber mainly includes the following components and their functions:
1. Hydroxyl-terminated polydimethylsiloxane: As the main component, it provides the basic properties of the silicone rubber.
2. Methyl tributanone oxime silane: As a crosslinking agent, it promotes the curing reaction of the silicone rubber.
3. Fumed silica: As a reinforcing filler, it improves the mechanical strength and wear resistance of the silicone rubber.
4. Calcium carbonate: Increases the hardness and stability of the silicone rubber.
5. Silane coupling agent: Such as SF-S550, it enhances the bonding force between the filler and the silicone rubber matrix.
6. Dibutyltin dilaurate: As a catalyst, it accelerates the curing reaction.
7. Dyes: Used to adjust the color of the silicone rubber. Specific Formula Examples:
• Single-component oxime-type room temperature RTV silicone rubber formula:
o Hydroxyl-terminated polydimethylsiloxane: 100 parts
o 201 silicone oil: 32 parts
o Methyl tributanone oxime silane: 7-9 parts
o Fumed silica: 8 parts
o Calcium carbonate: 45-55 parts
o Silane coupling agent SF-S550: 2 parts
o Dibutyltin dilaurate: trace amount
o Dye: appropriate amount
• Two-component room temperature RTV silicone rubber formula:
o Component A:
Hydroxyl-terminated polydimethylsiloxane: 100 parts
Ultrafine calcium carbonate: 40-50 parts
Fumed silica: 9-10 parts
Titanium dioxide: 5 parts
o Component B:
Ethyl orthosilicate: 7-8 parts
n-Butyl borate: 3-4 parts
n-Butyl titanate: 3-4 parts
Dibutyltin dilaurate: trace amount
Preparation Method: Mix each component according to the formula ratio to prepare a mixed compound through mixing or compounding processes, and then carry out a vulcanization reaction at room temperature to form an elastic vulcanized rubber.
Application Fields: Neutral room temperature vulcanizing silicone rubber is widely used in electronics, light industry, machinery, construction, chemical industry and other industries as adhesive, sealant, insulation, moisture-proof, and shock-absorbing materials, and is particularly suitable for waterproofing, sealing, and potting of electronic components, semiconductor materials, electric heaters, and electronic instruments.
