Product Overview
BISCO® MS-1640 — Firm Closed-Cell Silicone Foam — Technical Overview & FAQs
Product Overview
BISCO® MS-1640 is a firm, closed-cell silicone foam engineered for demanding sealing, cushioning, and vibration-isolation applications where high mechanical strength and environmental durability are essential.
Its firm density provides excellent resistance to compression set, ensuring reliable long-term sealing performance under higher loads or repeated mechanical stress.
MS-1640 combines thermal stability, weather resistance, and flame performance, making it ideal for aerospace, transportation, and industrial enclosures that require durable sealing and vibration damping over extended service life.
Applications
Heavy-duty gasketing and vibration isolation pads
Aerospace, defense, and transportation sealing systems
High-load flanged joints or bolted covers
HVAC, lighting, and industrial equipment requiring heat and weather resistance
Flame-resistant sealing in electronic or power enclosures
Key Properties
Density: 28 lb/ft³ (450 kg/m³)
Compression Force Deflection (25%): ≈ 13 psi
Compression Set (22 h @ 212 °F): ≤ 5 %
Tensile Strength: 100 psi
Elongation at Break: 90 %
Thermal Conductivity: 0.050 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-1640 used for?
MS-1640 is a firm, closed-cell silicone foam used in applications requiring long-term sealing, vibration damping, and flame resistance under high mechanical pressure or load.
What makes MS-1640 different from other silicone foams?
It has a higher firmness and density (≈ 28 lb/ft³) than softer grades like MS-1600 or MS-1630, offering greater load-bearing capacity and structural stability.
Can MS-1640 withstand high temperatures?
Yes — it maintains elasticity and sealing performance from –67 °F to 392 °F (–55 °C to 200 °C), even after prolonged heat aging or thermal cycling.
Is MS-1640 flame rated?
Yes. It meets UL 94 V-0, UL 94 HF-1, and FAR 25.853 flame resistance standards for aerospace and industrial safety compliance.
Can MS-1640 be supplied in custom-cut or adhesive-backed formats?
Absolutely. It is available as sheets, rolls, or precision die-cut gaskets with optional silicone or acrylic PSA for peel-and-stick assembly.
Request BISCO® MS-1640 samples, technical data, or custom gasket fabrication support from H-O Products — your partner in precision silicone materials and EMI/RFI sealing solutions - contact us.