A new
family of polymeric, lubricant-infused, nanostructured wrinkled
surfaces was designed that effectively retains inert nontoxic silicone
oil, after draining by spin-coating and vigorous shear for 2 weeks.
The wrinkled surfaces were fabricated using three different polymers
(Teflon AF, polystyrene, and poly(4-vinylpyridine)) and two shrinkable
substrates (Polyshrink and shrinkwrap), and Teflon on Polyshrink was
found to be the most effective system. The volume of trapped lubricant
was quantified by adding Nile red to the silicone oil before infusion
and then extracting the oil and Nile red from the surfaces in heptane
and measuring by fluorimetry. Higher volumes of lubricant induced
lower roll-off angles for water droplets, and in turn induced better
antifouling performance. The infused surfaces displayed stability
in seawater and inhibited growth of <i>Pseudoalteromonas spp</i>. bacteria
up to 99%, with as little as 0.9 μL cm<sup>–2</sup> of
the silicone oil infused. Field tests in the waters of Sydney Harbor
over 7 weeks showed that silicone oil infusion inhibited the attachment
of algae, but the algal attachment increased as the silicone oil was
slowly depleted over time. The infused wrinkled surfaces have high
transparency and are moldable, making them suited to protect the windows
of underwater sensors and cameras