Sealant types and Their Uses

Sealants refer to a wide variety of materials that are used to close the gaps between substrates, or various building materials.  Sealants are used to prevent air, gas, noise, smoke, liquid, or dust from penetrating small openings that cannot otherwise be closed.  Sealants begin as a viscous liquid, when applied, then dry into a solid.  Sealants of some sort are used in every level of civilization, from tarring the roof of a hut to weatherproofing a modern home with silicone caulk to specialty soundproofing.

In the past few decades, the sealant industry has globalized with the rest of the world market.  In fact, 60% of total global merchant demand of sealants comes from three major players.  Asia and India represent the highest growth market in recent years, due primarily to the rise of textile manufacture, electronics assembly, and woodworking.  Enduring woodwork would be impossible without the right sealants.

Sealant production has also responded to environmental concerns, with technological breakthroughs that have made sealants more effective and environmentally friendly.  Earlier generations of sealants commonly contained VOCs, or “volatile organic compounds.”  Advances in technology have produced Low-VOC and No-VOC sealants.  These new generation sealants are safer for the environment.  What’s more, they are applicable to a wider range of materials and conditions.

There are literally dozens of types of sealants, based on their chemical makeup and their various uses.  From dental sealants, to engine sealants, to household epoxy.  They are even used in the nanotechnology industry.  The most commonly recognized sealants are household sealants.  For example, the caulk used to seal a bathtub, window sill, or kitchen sink.

Sealants have three basic functions

1. A sealant fills a gap between two or more substrates.

2. Sealants form a barrier through the physical properties of the sealant itself and by adhesion to the substrate.

3. It maintains sealing properties for the expected lifetime, service conditions and environments.

Sealants are commonly grouped with adhesives, though they are different substances with distinct uses.  Adhesives are sometimes reformulated into sealants.  An adhesive is used to join to components together, like the panels of a cardboard box. While a sealant, though often sticky, is used to close gaps and openings where unwanted air and particles can pass through.  Adhesives are often stronger than sealants, but less flexible.  Sometimes the functions of sealants and adhesives overlap. Sealants do need to stick to what they are sealing, but that is not as important as the seal itself.

Sealants, though usually weaker than adhesives, have unique properties. Sealants, as opposed to simple adhesives, are particularly effective in keeping moisture in or out of the components they seal.  They provide soundproofing and thermal insulation.  Some sealants are quite effective as fire barriers.  Other sealants can have electrical insulating properties.  They are also used for finish work, like smoothing or filleting.

Sealants are a godsend in the field of home weatherproofing, and renovating kitchens and bathrooms.  The modern home would be impossible without the insulating properties of sealants.  This winter, try tracking down some of the drafts in your home – cracks and gaps around windows, under sinks, tubs and plumbing, or around electrical fixtures.  These are all places where household sealants, like silicone caulk and epoxy can make your home more comfortable and fuel-efficient.

Be sure to weatherize your home this season.  When doing so, don’t underestimate the utility and effectiveness of sealants.  Drafts can be eliminated and bills lowered all for the price of a few tubes of the right caulk.  There are numerous sealants on the market, each specialized for a different use.  Find out which ones are best for your needs.  Contact a local contractor that will answer your questions.

Some of the information in this report was gathered from The Third Edition of the Global Adhesive and Sealant Study: 2003-2006.  If you have questions about sealants and their uses, you may also contact the author of this article, Matt Millsap, a Tennessee based building and construction specialist.