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Dewetting of thin polymer films near the glass transition

F. Saulnier·E. Raphael·P. -G. de Gennes
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Abstract

Dewetting of ultra-thin polymer films near the glass transition exhibits unexpected front morphologies [G. Reiter, Phys. Rev. Lett., 87, 186101 (2001)]. We present here the first theoretical attempt to understand these features, focusing on the shear-thinning behaviour of these films. We analyse the profile of the dewetting film, and characterize the time evolution of the dry region radius, $R_{d}(t)$, and of the rim height, $h_{m}(t)$. After a transient time depending on the initial thickness, $h_{m}(t)$ grows like $\sqrt{t}$ while $R_{d}(t)$ increases like $\exp{(\sqrt{t})}$. Different regimes of growth are expected, depending on the initial film thickness and experimental time range.

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F. Saulnier, E. Raphael, P. -G. de Gennes. 2002-12-09. Dewetting of thin polymer films near the glass transition. https://doi.org/10.1103/physrevlett.88.196101

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