Authors: Marta Horecha Volodymyr Senkovskyy Konrad Schneider Anton Kiriy Manfred Stamm
Publish Date: 2010/10/28
Volume: 289, Issue: 5-6, Pages: 603-612
Abstract
PolyNisopropylacrylamide PNIPAMbased microgels covered with hydrophobic but waterpermeable shell were used for modification of a hydrophilic substrate with the aim to provide a ‘contraphilic’ wetting behaviour namely to make the surface more hydrophobic in water environment polar medium than in dry state in air nonpolar medium Bottomup approach has been applied for a stepwise preparation of a structured twocomponent surface Loosely packed microgels selforganised into quasiperiodic arrays were chemically grafted to the hydrophilic functionalised substrate Afterwards a surfaceinitiated polymerisation of isoprene was performed selectively from microgels making them hydrophobic The surface was found to be watersensitive as observed by in situ AFM measurements The surface fraction of the hydrophobic component increased from 13 in the dry state up to 25 in water due to swelling of the microgels However small contraphilic effect was recorded by water contact angle measurements because of a moderate lateral swelling of the coreshell microgels and due to a fast swelling of the microgels already upon the measurements
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