Wacker ELASTOSIL® RT 602 A/B – Light Gray Addition-Curing Silicone Rubber for Electronics & Sensor Encapsulation

Premium Heat-Resistant Potting Silicone for Professional Electronics and Sensor Applications

Wacker ELASTOSIL® RT 602 A/B is a pourable, addition-curing two-component silicone rubber (RTV-2) that cures at room temperature or accelerated at elevated temperature. The material has a low mixed viscosity of 3,500 mPa·s, a final hardness of Shore A 30 and a light gray final color. The mixing ratio is 9:1 (A:B) by weight, with the platinum catalyst in component A and the crosslinker in component B — use only components with the same lot number. With a pot life of approximately 80 minutes, a cure time of 24 hours at 23°C (accelerated to 5 minutes at 150°C) and excellent heat stability, this is a reliable all-round potting compound for the encapsulation of electronics and sensors.

Key Benefits

• Low mixed viscosity 3,500 mPa·s: flows well around components and fills fine details – ideal for fully encapsulating circuit boards and sensors.
• Hardness Shore A 30: flexible yet firm cure – provides mechanical protection without becoming brittle.
• Pot life approximately 80 minutes at 23°C: generous working time – sufficient time for pouring and vacuum degassing of larger or complex parts.
• Volume resistivity 10¹⁵ Ohm·cm: high electrical insulation – exceptionally suitable for insulating and encapsulating electrical circuits.
• Rapid heat cure down to 5 minutes at 150°C: strongly temperature-dependent curing – enables efficient series production.
• Excellent heat stability: retains its properties under prolonged thermal load – suitable for demanding electronics applications.

Typical Applications

• Encapsulation and potting of electronic circuit boards
• Protection of sensors in automotive electronics
• Measurement and control technology and sensor technology
• All-round potting compound for electrical components
• Manufacture of cast technical articles
• Applications with combined thermal and mechanical load

Processing Instructions:

1. Stir component A (light gray, 5,000 mPa·s) and component B (transparent, 200 mPa·s) thoroughly and separately before use to evenly disperse any settled filler.
2. Accurately weigh the components in a ratio of 9 parts A to 1 part B (by weight). Use only components A and B with the same lot number.
3. Mix both components thoroughly into a homogeneous mass. Tools that have been in contact with the platinum-containing component A must not come into contact with the crosslinker component B, as even traces of platinum can cause component B to gel.
4. Optionally degas the mixture under vacuum to remove trapped air. This is recommended when encapsulating components.
5. Pour the mixture within the pot life of approximately 80 minutes (at 23°C).
6. Allow to cure: approximately 24 hours at 23°C, or accelerated 20 minutes at 70°C, 10 minutes at 100°C or 5 minutes at 150°C (layer thickness 1 cm). Cure time depends strongly on the temperature, size and heat-sink properties of the potted part; run preliminary tests to optimize conditions.

Manufactured by Wacker Chemie AG, the world market leader in the development and production of silicones for industrial and technical applications.

Important Warning: Inhibition of Addition-Curing Silicones

Note: This is an addition-curing silicone (platinum cure). All surfaces must be clean and free of contaminants that inhibit curing. Inhibiting substances include sulfur-containing materials, plasticizers, urethanes, amine-containing materials and organometallic compounds — particularly organotin compounds. If a substrate's ability to inhibit cure is unknown, run a small-scale test first to determine compatibility.

Packaging and Storage

The 'best use before end' date of each batch is shown on the product label. Storage beyond this date does not automatically mean the product is no longer usable; in that case, check the required properties for quality assurance reasons. Store in a dry and cool place.

Professional Support

ELASTOSIL® RT 602 A/B is a proven all-round potting compound for professionals who require reliable, heat-resistant encapsulation of electronics and sensors. Unsure about the right curing conditions or dosage for your application? Contact us for technical data sheets, processing guides or product advice.