Master Bond MasterSil 323S-LO is an addition cured silicone that is not only electrically conductive, but also thermally conductive. This ASTM E-595 low outgassing rated product is designed for bonding applications where low stress is critical and is appropriate for use in vacuum environments. It can be utilized in the aerospace, electronic, opto-electronic, and specialty OEM industries.

MasterSil 323S-LO offers flexibility and toughness, with a Shore A hardness of 35 to 55, a low tensile modulus of less than 800 psi and an elongation of 50-100%, measured at 75°F. This enables it to withstand aggressive thermal cycling and mechanical shock, while offering a wide service temperature range from -80°F to +400°F [-62°C to +204°C]. MasterSil 323S-LO is a silver filled compound that has a volume resistivity of less than 0.003 ohm-cm and a thermal conductivity of 9-11 BTU•in/(ft²•hr•°F) [1.30-1.59 W/(m•K)] at room temperature. It bonds well to a wide variety of substrates, including metals, composites, glass, ceramics, rubbers as well as many types of plastics.

MasterSil 323S-LO has an easy to use 1:1 mix ratio by weight. The system features a paste consistency with minimal flow and does not rely on humidity access for curing. This formulation offers a variety of cure schedules at elevated temperatures, including 4 to 6 hours at 160-180°F, and 2 to 3 hours at 190-210°F. MasterSil 323S-LO is available for purchase in jars ranging from 20 gram kits to one pound kits.