Two component toughened epoxy system complying with FAR standard 14 CFR 25.853(a) for flame retardancy

Key Features

  • Tested as per Amendment 25-116 and Part 25 Appendix F
  • Passes horizontal burn test
  • One to one mix ratio
  • Withstands 1,000 hours 85°C/85% RH

Product Description

Master Bond EP90FR-HFL is a two component flame retardant epoxy system for bonding, sealing, coating and potting. It has been tested to the standards mentioned above and passes the demanding horizontal burn test specification. Thus, it can be considered for use in many specialized aviation applications. It should be noted that this epoxy is toughened and excels in withstanding rigorous thermal cycling as well as mechanical shock and vibration. Some of the uses include aircraft windows, lighting assemblies and baggage equipment areas, among others. Also, it should be noted that EP90FR-HFL is a non-halogenated type system, which is a big positive regarding handling and environmental issues.

EP90FR-HFL has an easy to use, forgiving, one to one mix ratio by weight. This low viscosity system has a long open time with the recommended curing for optimizing properties being overnight at room temperature followed by 3-4 hours at 150-200°F. Since it is a top notch electrical insulator, it can be a candidate for electronic potting and sealing applications. It bonds well to a variety of substrates including metals, composites, glass, ceramic and many plastics. Since it has some flexibility, it is particularly useful for bonding dissimilar substrates. It has good chemical resistance to water, fuels and oils. The service temperature range is -60°F to +250°F. The color of Part A is black, Part B is white. When mixed, it will turn gray. EP90FR-HFL is a specialty type product for aviation and avionic applications primarily where a toughened epoxy is desirable and the requirements of the horizontal burn test are specified.

Product Advantages

  • Easy to use, forgiving 1:1 mix ratio by weight
  • Splendid toughness, can withstand rigorous thermal cycling
  • Impressive electrical insulator
  • Low shrinkage upon curing
  • Reliable adhesion to a wide variety of substrates
  • Meets the stringent horizontal burn test portion of the FAR standard 14 CFR 25.853(a) for flame retardancy
  • Non halogen filler

Industrial Certifications

FAR 25.853(a) for Flame Retardancy

1,000 Hours at 85°C/85% RH

Meets EU Directive 2015/863




Premixed & Frozen Syringe

EP90FR-HFL is available is various sizes and units to accommodate customer's needs.

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