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. 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,” says Rohit Ramnath, Senior Product Engineer. “Also, it meets NASA low outgassing specifications which is a prerequisite for many aerospace, electronic, and optical applications.” 

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 convenient 1:1 mix ratio, and cures in 2-3 days at room temperature or 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.