Alternatives to Silicone – GreenBuildingAdvisor – GWC Mag

Silicon (not to be confused with silicone), is number 14 on the periodic table of elements and happens to be second most abundant element in the earth’s crust. It was first isolated as an element in the 1820s and has since been used to create products we use in everyday life. It is used in semiconductors and photovoltaic panels. Silicon dioxide, or silica, is used in concrete and in the production of ceramics. Silicon is also used to create silicone, a manmade compound with many applications. It is used in the medical profession (think: implants) and as a lubricant in industrial applications. This article, however, will focus on its use in the construction industry, as a sealant.

Sealant terminology

A sealant is a material used to keep something—liquid, air, dust, sound, and/or heat—in or out of a joint or opening; it’s a type of mechanical seal. Sealant is often referred to as “caulking,” I’ve also heard “silicone” used as a blanket term when describing sealants. Silicone is a synthetic or man-made polymer that is one type in a family of many different formulations of sealants. It was first introduced in the construction industry in the mid 1950s and is a popular sealant today, even with many other choices available.

Adhesion is the “stick to others” part of a sealant. Adhesion is an attraction between two different materials. A related term, adhesion failure, is the loss of connection between the sealant and substrate.

Cohesion is the “stick to itself,” meaning it’s the force of attraction between the same molecules. Cohesion failure is when the sealant loses bond with itself but the bond to the substrate remains.

Elasticity/elongation is the stretch and return to normal of a material. (My favorite analogy is yoga pants; they stretch…