Master Bond MasterSil 153AO is an addition-cured two-part silicone with a self priming property.
It has a high tensile lap shear strength, especially for a silicone. The system is thermally conductive and electrically insulating.
This silicone product has an elongation between 100-120%, and a tensile lap shear strength of 700-800 psi. It provides a thermal conductivity of 0.93-1.08 W/(m•K), a volume resistivity of more than 1014 ohm-cm, a coefficient of thermal expansion of 150-180 x 10-6 in/in/°C, and hardness of 65-75 Shore A. It is serviceable over the temperature range of -65°F to +400°F.
With an easy to use mix ratio of 1 to 1 by weight, MasterSil 153AO cures with the addition of moderate amounts of heat. For example, optimal cure schedule is overnight at room temperature followed by 2-4 hours at 135°F-185°F. Upon mixing, it retains its smooth paste consistency and minimal flow. It has a long working life of 4 to 6 hours for a 100 gram mass at 75°F.
This compound bonds well to a variety of substrates including metals, glass, ceramics, many plastics and silicone rubbers. MasterSil 153AO is generically low outgassing, contains no solvents, has a low linear shrinkage upon curing and is RoHS compliant.