Why do commercial roof protective coatings use acrylic?

Applying a protective coating over your commercial roof surface is one of the best ways to reflect the sun’s harmful UV rays. Many of these coatings are acrylic-based, but why is that?
You’re probably already familiar with one acrylic-based product: PlexiGlas. Manufacturers use PlexiGlas to create a wide variety of products, everything from boat hulls to construction ladders, patio tables, and more. It’s a popular material of choice because of its durability and strength. PlexiGlas is composed of only monomers, highly durable chemical-based building blocks. Acrylic polymers are a mixture (hence the name “poly-“) of acrylic with other material bases that has the strength and durability of acrylic with the flexibility of the additional material, such as silicone.
Why not use just acrylic for coating a commercial roof? That’s a great question! Acrylic is incredibly strong but it’s not very flexible. When acrylic is applied, it quickly loses any flexibility and doesn’t conform well to curves and bends in the roof over time. This is why the best types of roof coatings are polymers.
Acrylic polymers have now been developed specifically for roof coating applications. The acrylic’s durability helps deflect the UV transference and the flexibility created by the polymer additive, such as silicone, allows the coating to form over virtually any roofing substrate. By deflecting the UV’s heat transfer, the acrylic coating protects the spray polyurethane foam (SPF) from absorbing and deteriorating with the same UV rays. The acrylic coating is up to the task that a basic silicone coating wouldn’t be able to provide because silicone doesn’t have the same level of durability.
Our R&A Contracting team loves installing Thermo-Flex from Lapolla Industries. A term that’s often associated with acrylic coatings, such as Thermo-Flex, is “elastomeric”. That means that it has strength in thickness (“viscosity”) and flexibility (“elasticity”). You want a roof coating that can bend as your roof settles with your building over time without exposing any cracks in your building envelope.