250 C High Temperature Flexible 1:1 Silicone Potting Compound and Silicone Encapsulant for Electronic Component Protection

HN-8806A/B is a two-component addition-cure silicone potting compound supplied at a 1:1 mix ratio by weight. It flows at 2000-3000 mPa·s and cures at room temperature in 2-3 hours or in 12 minutes at 80 °C into a flexible grey Shore A 45 ± 5 elastomer. The cured material delivers a −50 °C to 250 °C high-temperature service range, extremely low cure shrinkage with CTE 210 µm/(m·°C), deep-section curing without voids, 0.76 W/m·K thermal conductivity, 25-30 kV/mm dielectric strength, 1.0 × 10¹⁶ Ω·cm volume resistivity and UL 94 V-0 halogen-free flame retardancy. Addition cure releases no heat and no by-products, so electronic components, windings and solder joints are protected without corrosion or stress through thermal cycling.

• High temperature 250 °C service range – the flexible elastomer keeps its electrical and mechanical properties from −50 °C cold start-up to 250 °C continuous heat load, covering wide-temperature electronic components and power assemblies.
• Flexible Shore A 45 ± 5 elastomer – the semi-flexible body absorbs vibration, thermal expansion and mechanical shock instead of transferring stress to fragile components, ceramic parts and solder joints.
• Deep-section curing without voids – thick component blocks and large castings cure through the section with no exotherm, so internal voids and incomplete cure are avoided.
• Extremely low cure shrinkage with CTE 210 µm/(m·°C) – stable dimensions and terminal spacing through repeated thermal cycling, with low stress on embedded parts.
• Low viscosity 2000-3000 mPa·s on both components – fast flow around dense component arrays, fine windings and narrow cavities for complete encapsulation.
• 1:1 mix ratio and 18-24 min pot life – equal-part weighing for manual pots or direct 1:1 meter-mix dispensing, with enough working time for multi-cavity molds.
• Dual cure schedule – 12 minutes at 80 °C for volume lines, or 2-3 hours at 25 °C for large cavities and low-volume work.
• UL 94 V-0 halogen-free flame retardancy – V-0 classification with RoHS and REACH compliance for EU and North American OEM documentation.
• 0.76 W/m·K thermal conductivity – conducts heat from components and windings into housings, heat sinks and cold plates.
• 25-30 kV/mm dielectric strength and 1.0 × 10¹⁶ Ω·cm volume resistivity – high electrical insulation for terminals, windings and high-voltage parts.
• Non-corrosive, no by-products, ageing resistant – no attack on copper, aluminium or plated terminals, with stable performance over long service life.
• 50 kg bulk kit – Component A 25 kg plastic barrel plus Component B 25 kg plastic barrel, with TDS, MSDS, RoHS and REACH declarations and batch COA.

All values are measured under standard conditions (25 °C, 50-60% RH) after the recommended cure schedule and are for reference only. Actual performance may vary with application conditions.

• Pre-mix – stir Component A and Component B separately before use, because fillers may settle during storage; reseal containers tightly after use.
• Weigh or meter – weigh A and B at exactly 1:1 by weight on a precision scale, or run the pair through a 1:1 meter-mix dispenser.
• Mix – mix thoroughly in the same direction to limit air entrapment and scrape the container walls and bottom; uneven mixing may cause local incomplete cure.
• Degas (optional) – vacuum degas for void-sensitive components and deep-section castings.
• Pot – pour or dispense the mixed compound into the clean, dry device within the 18-24 minute pot life and ensure complete coverage.
• Cure – 12 minutes at 80 °C on heat-accelerated lines, or 2-3 hours at 25 °C; do not move or stress the part during cure.

Cure inhibition notice: this addition-cure silicone may fail to cure in contact with organotin or tin-containing silicones, sulfur and polysulfide compounds, amine or ammonia-containing items, polyurethane rubber, phosphorus compounds, organic acids and solder flux residues. Clean substrates and tools before potting, and do not mix with condensation-cure (acetoxy) silicone, epoxy or polyurethane.

HN-8806A/B is specified for high-temperature, flexible and low-shrinkage protection of electronic components in the following assemblies:

capacitortransformerinductorreactorchokecoil windingrelaycontactorfuse holderterminal blockconnectorbusbarPCBAcircuit board

power moduleIGBT moduleMOSFET moduleSiC power devicerectifier bridgethyristorDC-DC converterOBC on-board chargerinverterswitching power supplyUPS moduleserver and data center PSU5G base station powertelecom rectifier

motor statormotor coilpump electronicsEV battery packbattery moduleBMS boardcharging pilecharging moduleESS battery rackPCS cabinetPV inverterphotovoltaic junction boxwind power converterrail traction moduletrackside electronicsmarine power unitautomotive ECU board

temperature sensorpressure transducerproximity sensorPLC moduleindustrial controllerinstrument modulesmart meterenergy meterLED driverLED power supplyhousehold appliance control boardpower tool controllere-bike and scooter controllerwelding machine power stageinduction cooker boardelectronic ballastoutdoor lighting drivermedical device electronics

• Standard bulk kit – Component A 25 kg plastic barrel plus Component B 25 kg plastic barrel, 50 kg per A+B set.
• Pallet and export packing – barrels palletised and strapped for sea and air freight; private label and drum marking available.
• Documentation – TDS, MSDS, RoHS and REACH declarations and batch COA issued with every shipment.
• Storage – 25 °C in original tightly sealed containers, protected from direct sunlight, moisture and extreme temperatures.
• Shelf life – 6 months from date of manufacture when stored unopened and properly sealed; inspect and test material past shelf life before use.
• Transport – classified as non-dangerous goods (general chemicals); handle with care to prevent leakage.
• Supply capacity – 50 tons per month with OEM and private label service.

Shenzhen Hanast New Materials Co., Ltd. produces liquid silicone materials at its Guangdong base and supplies addition-cure and condensation-cure silicone for electronic potting, thermal management and mould making. Every lot ships with TDS and MSDS documentation and complies with RoHS, REACH and UL 94 V-0 requirements. TDS reference: HANAST-TDS-004 Rev.1 (2024-08-30).