Description
BISCO® RS-840 Very Firm Silicone from Rogers Corporation is a premium cellular silicone material designed for critical sealing, gasketing, and insulation applications that require exceptional firmness and durability. Positioned at the firm end of the BISCO® Silicone Cellular series, RS-840 offers the weight advantages of a foam with the sealing capabilities of traditional sponge rubber, making it ideal for high-compression, high-performance environments.
This closed-cell silicone features patented cell structure and chemistry, delivering long-term reliability even in extreme operating conditions, including high heat, cold, moisture, UV exposure, and ozone. It maintains performance in a temperature range from -55°C to +200°C (-67°F to +392°F), with a low water absorption rate and excellent compression set resistance.
RS-840 is commonly used in transportation, electronics, industrial enclosures, and lighting, offering engineers a lightweight yet resilient material for demanding applications.
Key Features and Benefits of BISCO® RS-840:
- Very firm durometer for high compression load applications
- High temperature resistance (up to 392°F / 200°C)
- Low compression set for long-term sealing performance
- UV, ozone, and weather-resistant—ideal for outdoor and exposed environments
- Closed-cell structure—low water absorption (<1%)
- Excellent vibration dampening properties
- Available in multiple standard thicknesses, up to 15.88 mm (0.625”)
- UL 94 V-0 flame rated for enhanced fire safety
Common Applications:
- Seals and gaskets for enclosures and housings
- Automotive and aerospace insulation pads
- LED lighting thermal barriers
- HVAC and appliance gasketing
- Industrial control panels and electronics packaging
- Anti-vibration mounts and shock absorption systems
💡 Standard density: 495 kg/m³ (31 lb/ft³)
💡 Compression force deflection: 22–38 psi
💡 Available in gray and various thicknesses with standard tolerances