One and two component ultra soft silicone adhesives, sealants, coatings, potting/encapsulation compounds have proven effective in stress relieving applications. These systems are often employed in bonding and potting applications involving dissimilar substrates with CTE mismatches such as ceramic to plastic and aluminum to glass. Products offer stable performance in hot/cold environments (-80°C to +300°C) resist exposure to vibration, impact, shock and moisture, atmospheric contaminants. They are also noted for their long term durability, superior electrical insulative characteristics even when subjected to humidity, elevated temperature exposure and reworkability. USP Class Vi and ISO 10993-5 approved grades are biocompatible and are used in the assembly of medical devices. Specific formulations meet UL94V-0 and UL94V-1 flame retardant requirements. Heat dissipative silicone products have excelled in thermal management as electronic devices have become smaller and more powerful. This has played a key role in enhancing their reliability.
Unfilled silicone compounds have a softer durometer than filled systems. Flowable low viscosity two component addition curing potting/encapsulation products have low exotherm, can cure in deep sections and have accelerated cure schedules at high temperatures. Medium viscosity/paste materials mitigate thermal-mechanical stress, protect fragile components/parts in IGBT modules, electronic controls, LED devices and in attaching components on PCB's. Fast curing systems have been developed for high volume assembly bonding and form-in-place gasketing. Smaller, thinner, lighter miniaturized microelectronic devices have been succesfully potted/encapsulated with 100% solid, bubble/tack free, high purity, water repellent low modulus Master Bond silicone compositions.
Easy to use, one component MasterSil 709 bonds well to multiple substrates, has good flow properties and a tack-free time of 15-20 minutes at 75°F. This product has a Shore A hardness of 25-35 and an elongation of 300-400%. It is serviceable from -75°:F to +400° F. MasterSil 153 is an addition cured two component system with a convenient 1 to 1 mix ratio by weight. It has a long pot life, low exotherm, outstanding electrical insulation characteristics and a soft durometer. This silicone system offers repairability and is self priming. Neutral curing, non-corrosive NASA low outgassing approved MasterSil 920-LO has high optical clarity and Shore A hardness of 25-35. Thermal cycling and shock resistance is exceptional. Vacuum compatible MasterSil 970-LO is a two component composition with a moderate viscosity and good flow. It has an impressive physical strength profile, complies with ASTM E595 specifications and has a 200-250% elongation.
