A Non-destructive Method for Characterizing Surface Mechanical Property of Polymeric Coatings under Accelerated Weathering
Li Piin Sung, Hsiang C. Hsueh
The surface of coatings and plastics is the first target in any degradation process initiated by ultraviolet (UV) radiation or mechanical stress (via scratch and abrasion). Surface damage can lead to changes in optical, morphological, and mechanical properties, pathways for ingress of moisture and corrosive agents. Current test methods for monitoring performance of protective coatings focus on chemical properties and optical properties, such as color and gloss measurements, or invasive tests such as abrasion and cross cut adhesion. In this study, a non- destructive performance protocol using nanoindentation methodology for characterization and quantification of surface performance properties will be presented. Polyurethane (PU) coatings with different polyol compositions were chosen for this study. Coating specimens were exposed to UV radiation in a well-controlled, high-intensity UV chamber. Exposed specimens were removed at specified UV dose intervals for surface modulus/hardness and scratch resistance characterization via nanoindentation and scratch test. The effect of polyol type and UV radiation on the scratch damage (scratch morphology) will be investigated and correlated to the surface hardness and modulus of the materials.
and Hsueh, H.
A Non-destructive Method for Characterizing Surface Mechanical Property of Polymeric Coatings under Accelerated Weathering, CoatingsTech Conference, Cleveland, OH
(Accessed June 3, 2023)