Measurements of t of water, oil and dodecane droplets are
included in Fig. 3. The variation of t for water droplets (Fig. 3a)
is in agreement with previously published reports which described the effect of nanoparticles on the surface of polymer-nanoparticle
composite films [8,12–16,52]. According to the results of Fig. 3a, as
the nanoparticle concentration increases wefirst record an increase
in t, which reaches amaximumvalue (10.4◦ for 0.5% w/w) and then
decreases. At the particle concentration of 1% w/w, t is minimized
(