Two component epoxy for potting, encapsulation, coating and sealing applications

Key Features

  • Low viscosity, long open time
  • Electrically insulative
  • Impressive optical clarity
  • Excellent temperature resistance and physical strength
  • Meets NASA low outgassing specifications
  • Withstands 1,000 hours 85°C/85% RH

Product Description

Master Bond EP121CL-LO is a two component, high performance epoxy resin system that features very low viscosity and an extraordinary long open time at room temperature of at least 2-3 days. It does, however, require oven curing. The mix ratio is a relatively easy to use 100:80, by weight. A typical cure schedule is 2-3 hours at 250°F followed by 5-8 hours at 300°F with a 2 hour or longer post cure at 350°F, although, a number of variations are possible. It has excellent adhesion to a wide variety of substrates including metals, composites, glass, ceramics and many rubbers and plastics. EP121CL-LO is particularly prominent for applications involving rigorous electrical insulation properties. Another attractive feature is its excellent physical strength profile. It offers superior chemical resistance to water, oils, acids, bases, fuels and many solvents. The service temperature range is -80°F to +500°F. EP121CL-LO is a specialty type system that is used in a variety of aerospace, electronic and OEM type applications.

Product Advantages

  • Low viscosity, long open time
  • Splendid thermal stability
  • Marvelous electrical insulation properties
  • Great optical clarity
  • Meets NASA low outgassing

Industrial Certifications

ASTM E595 Compliant

1,000 Hours at 85°C/85% RH

Meets EU Directive 2015/863





EP121CL-LO is available is various sizes and units to accommodate customer's needs.

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