So what separates a good elastomeric ter-polymer sealants from a bad one? Industry testing records many characteristics of coatings so that a standard of comparison can be used across products. For sealants, a couple of characteristics are essential for producing a good product
Elongation
As the name elastomeric suggests, these types of sealants are expected to stretch or elongate. As a building heats and cools over the course of the day, its exterior expands and contracts. If the sealant fails to expand and contract along with the building, it ruptures, and its protective qualities are ruined.
In industry testing, elongation is the percentage of the original length of the sample sealant at a given temperature to which the material can be stretched without breaking. In other words, the higher the elongation percentage, the stretchier the material will be.
Adhesion
Adhesion is another critical factor for a good elastomeric sealant. If the product cannot create a strong bond with the surface, it will not be able to maintain seal integrity over time. Adhesion tests are performed by using the sealant to glue together two regular surfaces. Tests are usually performed between two slick surfaces, such as glass or metal, as well as between two rough surfaces, such as concrete. Adhesion is measured by the amount of pressure required to pull the two surfaces apart.
Industry testing also measures characteristics such as viscosity, solids by volume or weight and hardness. Although these characteristics are important, without a reasonable degree of elasticity and adhesion, an elastomeric sealant will not be able to perform up to expectations.
