Adhesives and Sealants

Flowable Adhesives

Although many of the silicone adhesives are designed to be non-flowable, in some applications it may be desirable to have a material with some flow. Dow Corning does provide a range of flowable adhesives, with some being self-leveling for filling channels. 

Check the Product Finder for a material with the combination of properties to meet the needs of your application.

Lower Temperature Cure Adhesives

Most of the adhesives require cure temperatures >100 C, but some products have been formulated to allow them to be cured at <100 C, i.e. 90 C for about 1 hour. These are especially useful for electronic devices that cannot withstand high temperatures and may also allow for faster process operation.

UV Dyed Adhesives

In some applications it is desirable for quality control inspection to determine that the adhesive has been properly applied. For these applications Dow Corning provides a number of adhesives that contain UV fluorescing dyes to allow the use of sensors or visual inspection under black light to ensure that the needed adhesive coverage has been obtained before the parts are assembled and the adhesive is cured.

Thermally Conductive Adhesives

By the addition of higher levels of fillers, the thermal conductivity of the silicone adhesives can be increased significantly. Thermally conductive adhesives are designed to remove heat from sensitive circuits to the ambient environment, generally through an attached heat sink, heat spreader or chassis. They also serve as durable dielectric insulating materials, barriers against environmental contaminants and act as stress-relieving shock and vibration absorbers over wide temperature and humidity ranges.

Without the addition of extra fillers, a typical value for the coefficient of thermal conductivity is roughly 0.18 watts/meter-K, with some of the adhesives reaching 0.35 watts/meter-K. Adding other conductive filler increases the thermal performance from 0.18 to greater than 3.0 watts/meter-K. Check the Product Finder for a material with the combination of properties to meet the needs of your application. You may also want to look at the product section on Wet Dispensed or Precured Pads and Film Thermal Interface Materials.

Low or Controlled Volatility Adhesives

In some applications, low molecular weight volatiles from the adhesives can result in problems. This can range from volatiles re-condensing onto surfaces that negatively impact adhesion or fog optical sensors or can lead to decomposition of volatiles under high voltage or high temperature conditions.  For these cases, special low volatility intermediates are used to formulate Dow Corning’s low volatility products. Some of the adhesives have volatile content low enough to be designated as space grade.

Flame Resistance

The materials used in certain applications are required to meet special criteria such as those from Underwriters Laboratories for flammability. There are adhesives, which possess a UL 94V flammability classification.

Extra Low Modulus

In some cases, extremely low modulus is needed. Dow Corning has some special formulations for these applications, where it is important for retention of the adhesive at the surface even with very high elongation.