With so many products to choose from, selecting the right
building sealant may seem like a daunting task. Selecting the wrong building
sealant, or applying the correct sealant in the wrong manner, can have serious
consequences. Mike Blaszkowksi, Dow Corning Marketing manager, recommends that
you keep the eventual application of your sealant in mind, and also make sure
it has the following characteristics.
1. Stability Over a Wide Temperature Range
Once fully cured, high-quality sealants perform across a range of temperatures.
The best sealants can withstand temperatures between -85° and 599°F
(-65–315°C). Select a sealant that functions reliably at temperatures outside
the performance range to accommodate unexpected temperature changes.
2. Weather Resistance and Chemical Stability
UV rays, radiation and weather can cause low-quality sealants to crack, crumble
and become brittle, compromising the seal over time. Look for sealants with
good resistance to these and other erosive factors. Also, some organic sealants
react to atmospheric pollutants or chemicals much like iron reacts with water
to produce rust. Use a sealant that does not readily degrade after prolonged
contact with common elements and industrial chemicals.
3. Good Bond Strength
Good industrial-assembly sealants provide durable adhesion to a variety of
building materials, including glass, ceramics, wood masonry, and many metals
and plastics. A variety of factors contribute to the bond strength of
individual sealants, including chemical composition, cure type and substrate
penetration.
4. Low Flammability
In fire conditions, some sealants are more burn resistant than others. Silicone
sealants, in particular, are especially reluctant to burn, and many comply with
UL-flammability standards.
Most importantly, be sure to select a sealant that can perform at the highest
temperature you require but also offers a secure and flexible hold at lower
temperatures. When in doubt, consult with
a qualified expert.
For more information, visit www.dowcorning.com.
