| Abstract
| - A series of monodisperse poly(styrene-b-isoprene[-g-perfluoroacyl]) block copolymers wassynthesized by sequential anionic polymerization of styrene and isoprene. The perfluorinated ester sidechains were attached to the remaining double bonds of the isoprene block via oxidative hydroborationand esterification of the resulting alcohol by the corresponding perfluorinated acid chloride. Surfaces ofthe pure polymers or blends in polystyrene exhibit a notable fractional surface excess of the perfluorinatedside chains within the uppermost 100 Å depending on the surface preparation and the block copolymercomposition. Thus, these surfaces are highly hydrophobic having advancing water contact angles of upto 122°. When samples are heated to 340 °C, the perfluorinated side chains can be selectively cleaved offby a thermal ester cleavage, leaving the backbone of the polymer completely intact. As a result, thehydrophobicity of the resulting poly(styrene-b-isoprene) polymer surface is reversed to an advancing watercontact angle < 90°. The selective thermal ester cleavage in combination with a subsequent chemicalsurface derivatization may have the potential to selectively change the surface functionality. If the thermalcleavage is done locally, patterning of the surface functionality seems possible.
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