Flexible two component epoxy polysulfide system for high performance bonding, sealing, coating and potting

Key Features

  • Room temperature curing
  • Excellent thermal conductivity
  • Superior electrical insulation
  • Low viscosity and good flow properties
  • Withstands rigorous thermal cycling
  • Reliable resistance to fuels and oils

Product Description

Master Bond EP21TPFL-1AO is a two component, low viscosity epoxy polysulfide for high performance bonding, sealing, coating and encapsulation. The main focus of this material is genuinely good thermal conductivity and electrical insulation properties, as well as a high degree of flexibility. This enables EP21TPFL-1AO to be used in situations with intense thermal cycling along with thermal and mechanical shock. Its lower viscosity and easy flow make it well suited for many potting and encapsulation applications. Additionally, being a polysulfide based system, it has very good chemical resistance, particularly to fuels, oils, hydraulics and related compounds.

The handling is relatively straightforward. The mix ratio is a forgiving two to three by weight or volume. Upon mixing, the open time is conveniently long. It has very good adhesion to metals, ceramics, composites, glass, and many rubbers and plastics. The system should not be heated and will crosslink fully 3-5 days. The service temperature range is -60°F to +250°F. The system is color coded for easy mixing, Part A is black while Part B is off-white. This unusual blend of properties; specifically, flexibility, thermal conductivity chemical resistance, allows EP21TPFL-1AO to be a prime candidate for specialty applications in the electronic, aerospace, specialty OEM and related industries.

Product Advantages

  • Easy to handle; forgiving mix ratio
  • Superb thermal conductivity and electrical insulation values
  • Exceptional flexibility, withstands aggressive thermal cycling
  • Stellar chemical resistance profile
  • Fully cures at ambient temperatures
  • Lower viscosity, well suited for potting and encapsulation




EP21TPFL-1AO is available is various sizes and units to accommodate customer's needs.

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