Continuous Fabrication of Slippery Liquid-Infused Coatings on Rolls of Flexible Materials

We report continuous, spray-based
methods for the fabrication of
antifouling “slippery” liquid-infused porous surfaces
(SLIPS) on rolls or sheets of thin, flexible materials relevant in
a broad range of consumer and industrial applications. Our approach
is based on the simultaneous spraying of two reactive polymers and
leads to uniform and conformal coatings with (i) useful levels of
nano- and microscale porosity and (ii) levels of residual azlactone
reactivity that enable the facile introduction of hydrophobic character
needed to infuse and retain lubricating oils. This approach can be
used to fabricate transparent and mechanically robust SLIPS-based
materials that resist fouling by a broad range of fluids and gels,
including food-based substances, on rolls of polymer films and foils
commonly used to design consumer packaging. These spray-on methods
are compatible with continuous (e.g., roll-to-roll) processing approaches
used in many commercial and industrial settings. We demonstrate proof
of concept of this continuous approach to SLIPS fabrication using
a benchtop roll-to-roll setup to coat meter-scale lengths of flexible
plastic film. SLIPS-coated film produced using this roll-to-roll approach
was then used to design models of flexible food packaging (e.g., transparent
bags or sachets), containers, and adhesive “SLIPS-strips”
that can be affixed manually to secondary surfaces to impart temporary
nonadhesive properties. The approaches reported here enable fabrication
of antifouling materials on scales and in forms that would be difficult
to achieve using many existing methods for the design of SLIPS and
open the door to additional potential practical applications of liquid-infused
materials.