Dewetting of glassy polymer films.

نویسندگان

  • Vijay Shenoy
  • Ashutosh Sharma
چکیده

Dynamics and morphology of hole growth in a film of power hardening viscoplastic solid [ yield stress approximately (strain-rate)(n)] is investigated. At short times the growth is exponential and depends on the initial hole size. At long times, for n>1 / 3, the growth is again exponential but with a different exponent. However, for n<1 / 3 the hole growth slows and the hole radius approaches an asymptotic value at long times. The rim shape is highly asymmetric, the height of which has a power law dependence on the hole radius (exponent close to unity for 0.25<n<0.4). The above results explain recent intriguing experiments of Reiter [Phys. Rev. Lett., 87, 186 101 (2001)] on dewetting.

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عنوان ژورنال:
  • Physical review letters

دوره 88 23  شماره 

صفحات  -

تاریخ انتشار 2002