Product Overview
BISCO® MS-1670 — Ultra-Firm Closed-Cell Silicone Foam — Technical Overview & FAQs
Product Overview
BISCO® MS-1670 is an ultra-firm, closed-cell silicone foam designed for applications requiring maximum structural integrity, load-bearing strength, and long-term sealing reliability.
As the firmest grade in the BISCO MS series, MS-1670 provides exceptional resistance to compression set, deformation, and environmental aging. It maintains consistent sealing performance even under high-pressure compression and continuous thermal exposure.
This material delivers outstanding mechanical stability, flame resistance, and UV/ozone durability, making it a top choice for aerospace, defense, industrial, and transportation systems exposed to harsh environments.
Applications
Heavy-duty sealing for high-load enclosures and access panels
Aerospace and transportation gasketing under continuous compression
Vibration isolation and structural cushioning pads
Flame-resistant sealing in electrical and energy systems
High-pressure gasketing in mechanical and industrial assemblies
Key Properties
Density: 40 lb/ft³ (640 kg/m³)
Compression Force Deflection (25%): ≈ 23 psi
Compression Set (22 h @ 212 °F): ≤ 5 %
Tensile Strength: 120 psi
Elongation at Break: 70 %
Thermal Conductivity: 0.058 W/m·K
Operating Temperature Range: –67 °F to 392 °F (–55 °C to 200 °C)
Flame Resistance: UL 94 V-0 and HF-1
Weather, Ozone, and UV Resistance: Excellent
Compliances: FAR 25.853, ASTM D1056, UL 94, FMVSS 302
FAQs
What is BISCO MS-1670 used for?
MS-1670 is an ultra-firm closed-cell silicone foam used in high-load sealing, vibration damping, and structural gasketing applications that demand maximum compression resistance and mechanical strength.
What makes MS-1670 different from other silicone foams?
It’s the firmest and most dimensionally stable material in the BISCO MS series, engineered for superior compression control and durability under long-term mechanical stress.
Can MS-1670 withstand extreme heat and cold?
Yes — it performs from –67 °F to 392 °F (–55 °C to 200 °C), maintaining elasticity and sealing integrity through repeated thermal cycling and environmental exposure.
Is MS-1670 flame rated?
Absolutely. MS-1670 meets UL 94 V-0, UL 94 HF-1, and FAR 25.853 flame-resistance standards, making it ideal for aerospace and safety-critical systems.
Can MS-1670 be customized or adhesive-backed?
Yes — it is available as sheets, rolls, or precision die-cut gaskets, with optional silicone or acrylic PSA for peel-and-stick installation.
Request BISCO® MS-1670 samples, technical data sheets, or a quote from H-O Products to source high-performance silicone foam for your demanding sealing and vibration isolation applications - contact us.