Silicone Potting Compound for Electronics

Tough-Seal is a superior family of KEY sealants for potting electrical and electronic components that provides a reliable grip and exceptional encapsulating protection for any potting application where premium thermal cycling performance, excellent thermal shock resistance, and outstanding environmental and corrosion protection are a must.

Tough-Seal is available in six formulations that vary in gel time, viscosity, and hardness. From our self-leveling and medium viscosity formulations, to our glob-top formulation for localized potting, to our new UL 94 V-0 Listed formulation, Tough-Seal fits a wide variety of potting and encapsulating applications.
Tough-Seal is bulldog tough and bred to grip and protect, under the most aggressive conditions!

ToughSeal vs. Other Electronics Potting Compounds

Tough-Seal is a RoHS Compliant, easy-to-mix, two component durable hybrid epoxy elastomer that offers a unique combination of KEY properties not commonly found in just one potting compound. It offers the heat resistance of an epoxy, the flexibility of a urethane and the durable encapsulating protection of a silicone. ToughSeal is not a urethane, so it is isocyanate-free and it is not moisture sensitive.

With exceptional flexibility at temperatures as low as -103°F (-75°C) and high temperature resistance up to 302°F (150°C). Tough-Seal grips in the cold, when other potting compounds contract, and maintains a tough seal in the heat, when other potting compounds wilt. Tough-Seal does not crack, so electronic components remain protected from moisture. When exposed to moisure, Tough-Seal also offers Anti-Microbial protection. Tough-Seal does not support fungal growth and meets the requirements of MIL-STD-810G Method 508.6.
With very low exotherm in large volume pours, extremely low shrinkage, and little to no expansion or contraction with temperature changes, ToughSeal is gentler on sensitive circuitry, than hard epoxies, delivering low embedment stress upon cure and during thermal cycling.
Tough-Seal provides durable encapsulating protection that guards electrical components from exposure to the harmful effects of the environment better than typical epoxies, urethanes and silicones.

KEY Tough-Seal Properties:

  • Easy-to-mix, 2:1 ratio
  • Low Exotherm
  • Room or Elevated Temperature Cure
  • Faster and Moderate Gel Times
  • Isocyanate-Free
  • Not Moisture Sensitive
  • Low Embedment Stress
  • High Elongation
  • Low Shrinkage
  • No Cracking
  • Exceptional Moisture Protection
  • Minimal Expansion & Contraction with Temperature Changes
  • Excellent Low Temperature Flexibility from -103°F (-75°C)
  • High Temperature Resistance up to 302°F (150°C)
  • Excellent Thermal Shock Resistance
  • Strong Adhesion to Thermoplastics & Wire Insulation
  • Aggressive Aluminum Adhesion
  • Anti-Microbial – MIL-STD-810G Method 508.6
  • RoHS Compliant

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Which Tough-Seal is Right for You?

Tough-Seal is a superior family of KEY sealants for potting electrical and electronic components, that offers a combination of KEY properties not commonly found in just one potting compound. There are four standard variations to chose from.

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How Tough-Seal Works

Tough-Seal offers the heat resistance of an epoxy and the flexibility of a urethane. Tough-Seal is isocyanate-free, delivers low embedment stress, minimal shrinkage and premium thermal cycling performance.

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Tough-Seal Performs

Tough-Seal is an ideal material for the encapsulation of sensitive electrical and electronic components that are subject to thermal cycling stress, thermal shock, and aggressive environmental conditions. Compare KEY Tough-Seal properties side-by-side.
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Tough-Seal Cures

Tough-Seal cures completely at ambient temperatures; although, Tough-Seal 21 and 31 are designed to have faster initial gelation times than Tough-Seal 22 and 32. Tough-Seal can be cured at room temp, elevated temp, and underwater.

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Tough-Seal Solves Problems

Tough-Seal grips and protects under the most aggessive conditions. Tough-Seal has been a successful solution in the agriculture, refridgeration, oil drilling and mining, snowmaking, and underwater lighting industries.

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Order a Tough-Seal Evaluation Kit

When you order a ToughSeal evaluation kit, you will receive everything you need to perform a high quality product evaluation.

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