What makes Moisture Cure Coatings semi-vapor permeable?

Moisture Cure Coatings are considered semi-vapor permeable primarily due to the molecular structure of the film that forms when the coating is applied and cures. This molecular structure plays a critical role in determining how moisture interacts with the coating. It allows for a limited exchange of vapor, balancing the need to protect the underlying surface from moisture intrusion while still permitting some degree of moisture vapor to escape. This feature is particularly beneficial in roofing applications, where it's important to allow any trapped moisture beneath the surface to evaporate without compromising the integrity of the roof system.

The molecular composition influences the arrangement and bonding of the material's molecules, which affects permeability. Therefore, the interaction between the coating and moisture is intrinsically linked to its chemical makeup, reaffirming why the molecular structure is the correct aspect to pinpoint in understanding the semi-permeability of Moisture Cure Coatings.