Thermally Conductive, Flowable Epoxy Meets NASA Low Outgassing Specifications

Master Bond has launched EP53TC, a two-component epoxy designed for bonding, sealing, coating, and small potting applications where efficient heat dissipation is crucial. The epoxy is formulated with a specialty filler with a particle size ranging from 5 to 30 microns. It is a flowable system with a mixed viscosity of 45,000-65,000 cps at room temperature. This filler size and its relatively flowable viscosity enable the EP53TC epoxy to fill small voids making it ideal for heat dissipation.

EP53TC meets ASTM E595 NASA low outgassing specifications and provides reliable electrical insulation with a volume resistivity greater than 10¹⁴ ohm-cm. The material offers a thermal resistance of 10-15 x 10^-6 K•m²/W and a thermal conductivity of 2.3-2.6 W/(m•K). This epoxy exhibits dimensional stability with low shrinkage upon curing and a low coefficient of thermal expansion of 14-16 x 10^-6 in/in/°C. Mechanical properties include a tensile strength of 5,000 to 7,000 psi, a tensile modulus greater than 1,000,000 psi, and a Shore D hardness of 85-95. The service temperature range is from -100ºF to +300ºF (-73ºC to +149ºC).

A moderate heat cure is required to achieve optimal properties with EP53TC. The recommended cure schedule is 2 hours at 80ºC followed by a post-cure of 90-120 minutes at 125ºC. This epoxy is available in various packaging options, including ounce kits, quarter pint kits, half pint kits, pint kits, and quart kits.

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