Self-healing and dewetting dynamics of a polymer nanofilm on a smooth substrate: strategies for dewetting suppression.

The self-healing and dewetting dynamics of a polymer nanofilm on a smooth, partial wetting surface are explored by many-body dissipative particle dynamics. Three types of dewetting phenomena are identified, (i) spinodal decomposition, (ii) nucleation and growth, and (iii) metastable self-healing. The outcome depends on the surface wettability (θY), the polymer film thickness (h0), and the radius of the dry hole (R0).

Spreading dynamics of a precursor film of nanodrops on total wetting surfaces.

The spreading dynamics of a nanodrop on a total wetting surface is explored by many-body dissipative particle dynamics. Both smooth and rough surfaces with various spreading coefficients (S) are considered. The evolution of the spreading film is mainly characterized by the radius of the wetting area (R) and the apparent base radius (R) and the contact angle (θ) of the spherical cap.

Water-repellent hydrophilic nanogrooves.

The wetting behavior of a nanodrop atop a nanogroove on a smooth or a rough surface is explored by many-body dissipative particle dynamics and Surface Evolver. The nanogroove possesses the same contact angle (θ) as that of the surface. Depending on whether the groove is initially wetted or not, two critical contact angles beyond which the groove cannot be wetted are determined.

Meniscus Shape and Wetting Competition of a Drop between a Cone and a Plane.

The formation of a liquid bridge between a cone and a plane is related to dip-pen nanolithography. The meniscus shape and rupture process of a liquid meniscus between a cone and a plane are investigated by Surface Evolver, many-body dissipative particle dynamics, and macroscopic experiments. Dependent on the cone geometry, cone-plane separation, and wetting properties of cone and plane, three types of menisci can be observed before rupture and two types of wetting competition outcomes are seen after breakup.