Synthesis of smart switchable coatings

6Schematic of morphology variation of mixed polymer brush situated in non-selective (left) and selective (right) conditions. 

7 SPM topographical images of mixed PS-PVP brushes (grafted via PGMA anchoring layer) rinsed with ethanol (top row) and toluene (bottom row). Dimensions are 1 x Ipm with a 5nm vertical scale (a) 31% PS, (b) 65% PS and (c) 94% PS. 

8 AFM topographical images of PS-PVP mixed brushes of different thicknesses in their hydrophobic (toluene treatment), hydrophilic (ethanol treatment), and neutral (tetrahydrofuran (THF) treatment) states (1 x Ipm, vertical scale 5nm). Thickness of the grafted layer 9nm (top row) and 5nm (bottom row). 

9 AFM topography images (1 x l am ) of mixed PS-polyacrylic acid brushes treated with different solvent (a) benzene (water contact angle 80°) (b) THF (c) EtOH (water contact angle 40°). Thickness of PS/PAA 15/15 nm. 

The mobile epoxy groups located in the loops/tails of the adsorbed PGMA macromolecule are shown to be accessible to the functional groups of an end-functionalized polymer and thus available for grafting. The mobility of the loops/tails of PGMA could be also effectively used to develop a novel system, which is robust, and possesses wettability on demand. In fact, the responsive unary polymer brush (UPB) system described below benefited from the mobility of the PGMA loops effectively to switch surface properties.  

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