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QSIL553 (44 KG KIT)
CHT-QSIL553 (44 KG KIT)
QSil553 – Flame-Retardant, Thermally Conductive Two-Part Addition-Cure Silicone for High-Reliability Electronics Potting
QSil553 is a two-component, 100% solids, addition-cure silicone elastomer engineered for high-reliability potting and encapsulation of sensitive electronic assemblies. With a 1:1 weight ratio and a 100-minute pot life at 25°C, it offers extended working time for complex assemblies while delivering excellent thermal conductivity (~0.68 W/m·K) and UL 94 V-0 flame resistance (File No. E205830).
Cured rapidly at elevated temperatures (e.g., 15 minutes at 150°C) or fully at room temperature in 24 hours, QSil 553 forms a repairable, low-modulus elastomer (Shore A 45) that cushions components against thermal shock, vibration, and mechanical stress. Its grey-cured appearance, high Comparative Tracking Index (CTI: 600 V), and excellent electrical insulation make it ideal for automotive, industrial, and power electronics, including ABS control units, battery systems, and high-voltage modules.
Key Features
- UL 94 V-0 recognised (File No. E205830)
- High thermal conductivity: ~0.68 W/m·K
- 1:1 mix ratio by weight – simplifies dispensing and ensures batch consistency
- Long pot life: 100 minutes at 25°C – ideal for intricate or large-volume potting
- Addition-cure chemistry – no corrosive by-products; fully repairable
- Wide service temperature range: –55°C to 240°C (–67°F to 464°F)
- High CTI (600 V) – suitable for high-voltage tracking resistance
- Low mixed viscosity (6,000 cP) – enables easy mixing and degassing
Typical Applications
- Potting of ABS control units, power converters, and battery management systems
- Encapsulation of high-voltage connectors and automotive electronics
- Protection of industrial control boards in thermally demanding environments
- Applications requiring repairability, flame resistance, and thermal management
Technical Notes
- Tensile strength: 1.72 MPa (249 psi)
- Elongation: 240% – provides stress relief without rigidity
- Tear resistance: 7.8 N/mm (45 ppi)
- Dielectric strength: 500 V/mil
- Volume resistivity: 4.0 × 10¹⁴ Ω·cm
- Self-bonding: No adhesion to substrates may require surface treatment or priming
Cure options:
- Fast cure: 15 min at 150°C
- Room-temperature cure: 24 hours at 23°C
Processing Recommendations
- Mix Components A (grey) and B 1:1 by weight in a clean container
- Degassing under 30–50 mbar vacuum is recommended for hand-mixed batches
- For automated dispensing, use purged static mixers and ensure equipment is free of contaminants (e.g., sulfur-, tin-, or PVC-based materials that can inhibit cure)
- Store components below 38°C (100°F) in sealed containers
Storage & Shelf Life
- Shelf life: 24 months in original, unopened containers
- Max storage temperature: 38°C (100°F)
Packaging Options
- Available in matched A/B kits and bulk containers for manual or automated meter-mix-dispense systems.
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QSil553 – Flame-Retardant, Thermally Conductive Two-Part Addition-Cure Silicone for High-Reliability Electronics Potting
QSil553 is a two-component, 100% solids, addition-cure silicone elastomer engineered for high-reliability potting and encapsulation of sensitive electronic assemblies. With a 1:1 weight ratio and a 100-minute pot life at 25°C, it offers extended working time for complex assemblies while delivering excellent thermal conductivity (~0.68 W/m·K) and UL 94 V-0 flame resistance (File No. E205830).
Cured rapidly at elevated temperatures (e.g., 15 minutes at 150°C) or fully at room temperature in 24 hours, QSil 553 forms a repairable, low-modulus elastomer (Shore A 45) that cushions components against thermal shock, vibration, and mechanical stress. Its grey-cured appearance, high Comparative Tracking Index (CTI: 600 V), and excellent electrical insulation make it ideal for automotive, industrial, and power electronics, including ABS control units, battery systems, and high-voltage modules.