Low-viscosity, electrically-conductive epoxy meets ISO 10993-5 cytotoxicity standards

1 min read

Master Bond EP4G-80Med is a one-part epoxy designed for use in the assembly of medical devices.

This system is formulated with a non-metallic graphite filler, which leads to good thermal and electrical conductivity. It possesses a thermal conductivity of 1.44-1.73 W/(m•K) and a volume resistivity of 50-100 ohm-cm. Furthermore, it complies with the ISO 10993-5 guidelines and is considered to be non-cytotoxic. 

According to the supplier, EP4G-80Med bonds well to a variety of substrates including metals, glass, ceramics, rubbers and many plastics, and is very effective as an EMI/RFI shielding compound and can also be used for static dissipation purposes. This system cures readily in 60-90 minutes at 80°C.  

Post-curing for 1-2 hours at 80°C is commonly recommended as it will optimize the overall properties of the epoxy. Its curing profile makes it suitable for many applications involving heat-sensitive substrates.  

“The product’s unique feature is that despite incorporating a graphite-based filler material, it actually exhibits an excellent flow profile, especially for an electrically conductive system, with a viscosity of 4,000-10,000 cps. It also provides a low coefficient of thermal expansion of around 15-20 ppm/C at room temperature,” says Rohit Ramnath, senior product engineer. 

EP4G-80Med is a dimensionally-stable epoxy that offers a tensile strength of 2,000-3,000 psi, a tensile modulus exceeding 750,000 psi and a Shore D hardness of 75-85 at 75°F. This system has a high glass transition temperature of 130-140°C and is serviceable over the temperature range of -50°C to +175°C.  

EP4G-80Med has a relatively long working life of 8-12 hours and must be refrigerated or frozen for storage. This black in color product is packaged in 10cc and 30 cc syringes, which are shipped in dry ice. After thawing it is easy to apply. EP4G-80Med does not contain any solvents and is RoHS compliant.