Two part epoxy adhesive, sealant, coating and encapsulating system featuring superb acid resistance

Key Features

  • Convenient processing
  • Low viscosity, good flow
  • Good physical strength properties
  • Reliable electrical insulator

Product Description

Master Bond EP21AR is a two component epoxy resin system for high performance bonding, sealing, coating and encapsulating. It has a convenient 100 to 50 mix ratio by weight and is formulated to cure at ambient temperatures or more quickly at elevated temperatures. The optimum cure is overnight at room temperature followed by 2 to 4 hours at 150-200°F. EP21AR is 100% reactive and contains no solvents or diluents. It has very low linear shrinkage upon cure.

The primary purpose of utilizing EP21AR is to obtain exceptional acid resistance. The chart below describes its resistance to a wide range of acids. EP21AR bonds well to several substrates including metals, ceramics, composites, as well as many plastics and rubbers. The service temperature range is from -60°F to +250°F. The color of Part A is clear and Part B is amber clear. It is available in various colors upon request. EP21AR can be used as an adhesive, sealant, coating or potting system. It is particularly useful for coating tanks and vessels that contain acids. EP21AR is a candidate for aerospace, electronic, electrical, chemical processing and OEM where acid resistance is needed.

Product Advantages

  • Convenient 2 to 1 mix ratio by weight
  • Versatile cure schedules
  • Dependable electrical insulator
  • Good flow, easy to apply
  • High bond strength to both similar and dissimilar substrates
  • Available in many colors

Industrial Certifications

Meets EU Directive 2015/863



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EP21AR is available is various sizes and units to accommodate customer's needs.

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