Two component, highly flexibilized epoxy resin compound

Key Features

  • Electrically insulating
  • Thermally conductive
  • High peel strength and elongation
  • Passes NASA low outgassing test
  • Cryogenically serviceable down to 4K
  • Withstands 1,000 hours 85°C/85% RH

Product Description

Master Bond EP21TDC-2LO is a two component, highly flexible epoxy resin compound for high performance bonding, sealing, coating, and encapsulation. It is formulated to cure fully at room temperature or more quickly at elevated temperatures with the optimum being overnight at room temperature followed by 2-3 hours at 200°F. It has an easy to use one to three mixing ratio by weight. EP21TDC-2LO has outstanding toughness and, unlike most flexibilized epoxies, it passes NASA low outgassing test criteria. The cured compound exhibits a high elongation (greater than 25%), truly exceptional for a thermally conductive epoxy. EP21TDC-2LO produces very little heat after mixing, which allows for a long working life. This epoxy resin compound exhibits good tensile shear and peel strength for bonding and sealing many different substrates including metals, glass, ceramics, rubber and many plastics. The cured epoxy is an excellent electrical insulator with superior chemical resistance to water, oils and fuels. Most noteworthy is its ability to withstand thermal shock, thermal cycling and mechanical shock. It has a service temperature range of 4K to +250°F and has been successfully employed in a number of cryogenic applications. Master Bond EP21TDC-2LO is an exceptionally versatile system that offers the structural benefits of an epoxy, yet incorporates flexibility and very good thermal conductivity. It is widely used in the electronic, electro-optical and related industries. The color of Part A is gray; Part B is off-white.

Product Advantages

  • Convenient mixing: non-critical one to three mix ratio by weight
  • Easy application: product spreads evenly and smoothly; long working life
  • Excellent flexibility; exceptional thermal shock and resistance to aggressive thermal cycling
  • High thermal conductivity combined with good electrical insulation properties
  • Passes fungus resistance MIL-STD-810G

Industrial Certifications

ASTM E595 Compliant

1,000 Hours at 85°C/85% RH

MIL-STD-810G for Fungus Resistance

Meets EU Directive 2015/863




Premixed & Frozen Syringe

EP21TDC-2LO is available is various sizes and units to accommodate customer's needs.

Case Studies

In several published research articles, patents, and manufacturers’ specifications, scientists and engineers have identified EP21TDC-2LO for use in their applications due to its unparalleled performance in one or more areas. The table below highlights two research applications that use Master Bond EP21TDC-2LO.

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