| Abstract
| - Atomic force microscopy (AFM) was combined with surface analytical techniques to investigate the rarely addressedissue of the effect of seawater on the surface properties of a selected fouling-release coating, silicon elastomer RTV11(trademark of General Electric). The exposure of the RTV11 surface to seawater resulted in a modification of itsmorphology and mechanical properties, as confirmed by AFM and scanning electron microscopy (SEM). Surfacemodification was dependent on sample preparation and curing process, namely, curing agent concentration and relativehumidity during curing. The RTV11 surface remained largely unaltered for samples cured under 100% relativehumidity. SEM and X-ray photoelectron spectroscopy studies confirmed that the modified surface of RTV11 had thesame elemental composition as the unexposed surface of the elastomer and showed excess Ca. However, the modifiedsurface deformed plastically under load and was stiffer than the original surface. No major change was found onsurfaces exposed to nanopure water during similar times of exposure as in seawater, regardless of curing conditions.The rate of increase in the aggregate formation in seawater can be described by an exponential function, with a decayconstant of ∼4.99 × 10-3 min-1 and a pre-exponential factor of ∼1.77 × 10-2 μm/min.
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