Developing and Evaluating Early Rain Resistance in Exterior Architectural Coatings

摘要

High humidity and precipitation challenges the ability of exterior architectural coatings to properly cure and provide the necessary protection of exterior surfaces. To increase early rain resistance and decrease water sensitivity, different formulation techniques were investigated. Raw materials were evaluated in a standard starting point formula to generate an optimal formulation that reduces water sensitivity and surfactant leaching, while simultaneously increasing early rain resistance. Results for early rain resistance were determined by developing new testing methodology that varied environmental factors during the film curing process. We determined that using functional additives as well as increasing the hydrophobicity of the coating film can substantially increase early rain resistance.