MASTER BOND: Thermally Conductive, Electrically Nonconductive, Low-Outgassing Epoxy

The Master Bond EP40TC two-part epoxy system for bonding, sealing, and encapsulating meets NASA low outgassing requirements and is able to transfer heat without conducting electricity. (Image courtesy of Master Bond.)
Master Bond EP40TC is a two-part epoxy system designed for bonding, sealing, and encapsulating applications where thermal conductivity and electrical insulation are required. With a high thermal conductivity value of 8-11 BTU•in/(ft2 •hr•°F) [1.16-1.60 W/(m•K)], it is formulated with a small particle size filler, making it ideal for filling small cavities and applying the product in thin sections. Its volume resistivity is greater than 1015 ohm-cm.
“EP40TC’s key distinguishing factor is that there is no compromise on the bond strength while providing excellent elongation and toughness,” said Rohit Ramnath, senior product engineer. “It has a high strength profile with a tensile lap shear strength of 2,300-2,500 psi, an elongation of 60-70%, and a tensile modulus of 5,000-15,000 psi. Also, it meets NASA low outgassing specifications which is a prerequisite for many aerospace, electronic, and optical applications.”
Reportedly serviceable from -100°F to +300°F, this toughened system resists thermal cycling, vibration, and shock. EP40TC exhibits a high peel strength of 40-60 pli and Shore D hardness of 70-80 at 75°F. It features a 1:1 mix ratio and cures in 2-3 days at room temperature (faster with the addition of heat). This compound adheres well to a variety of substrates, such as metals, composites, glass, and many plastics. EP40TC is available in standard packaging, as well as premixed and frozen syringes.
Additional details are available at www.masterbond.com.
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