| Abstract
| - Contact angles of a series of n-alkanes (i.e., n-heptane to n-hexadecane) are studied on two functionalized maleimidecopolymers (i.e., poly(ethene-alt-N-(4-(perfluoroheptylcarbonyl)aminobutyl)maleimide) (ETMF) and poly(octadecene-alt-N-(4-(perfluoroheptylcarbonyl)aminobutyl)maleimide) (ODMF)). On the homogeneous ETMF films, all liquidsshow a smooth motion of the three-phase line. In contrast, on ODMF surfaces that are found to consist of mainlyfluorocarbons and small patches of hydrocarbons, short-chain n-alkanes show a stick−slip pattern. By increasing thechain length of the probe liquids, stick−slip is reduced significantly. The phenomenon is discussed in the frameworkof the Cassie equation. It is found that the upper limit of contact angles in the stick−slip pattern is given by theadvancing angle that would be obtained on the pure fluorocarbon surface, whereas the lower limit of the stick−slippattern is given by the Cassie angle.
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