Dewetting phenomena

This review has discussed the phase behavior of polymer blends and symmetric block copolymer melts in thin film geometry, considering mostly films confined between two symmetrical hard walls. Occasionally, also an antisymmetric boundary condition (i.e. one wall prefers component A while the other wall prefers component B) is studied. These boundary conditions sometimes approximate the physically most relevant case, namely a polymeric film on a solid substrate exposed to air or vacuum with a free, fiat surface (Fig. 1). The case where the film as a whole breaks up into droplets (Fig. 2) due to dewetting phenomena is not considered, however, nor did we deal with the formation of islands or holes or terraces in the case of ordered block copolymer films (Fig. 4b-d). 

Leizerson, I., Lipson, S.G., Lyushnin, A.V. Einger Instability in wetting-dewetting phenomena. Langmuir 20, 291-294 (2003)... 

Figure 9. Schematic representation of the disordering/dewetting phenomena as a function of the film thickness a) thick films demonstrate macroscopic dewetting of the ordered sublayers b) the sublayers collapse via stepwise coagulation of the bilayers c) a thin film of one and a half bilayer thickness remains stable. Reprinted with permission from Sheiko et al. Copyright 1996 American Chemical Society.

Two dimensionless numbers play a key role in inertial dewetting phenomena ... 

The application of aqueous formulations onto hydrophobic substrates such as polyolefins, other plastics, or waxy leaves is often problematic the low surface energy of these substrates leads to poor wetting behavior or even dewetting phenomena such as crater formation and crawling [82]. 

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