Thin polymer films are often used in advanced technological applications either as homogeneous coatings or as structured functional layers. Their stability and therefore potential usage is mostly determined by the wettability properties of the substrate and is rather well understood for single component liquids. However, in various applications the film consists of a binary mixture such as a polymer blend. For such systems the dynamics of the decomposition within the film and of the dewetting of the film itself may couple. This allows for new pathways of structuring like decomposition induced dewetting [1,2]. We derive an extended Model-H [3,4] coupling transport equations for momentum and concentration fields for the non-isothermal case. We complete the description by introducing boundary conditions at the free surface and the solid substrate [5]. After determining homogeneous and vertically stratified base states we analyze their lateral stability and show that depending on the energetic bias at the surface and the mean concentration the convective transport (i) promotes the instability and (ii) induces surface deflections for the stratified base states [5,6]. We acknowledge support by the EU under grant MRTN-CT-2004-005728 [1] M. Oron, T. Kerle, R. Yerushalmi-Rozen, and J. Klein, Phys. Rev. Lett. 82,236104 (2004). [2] R. Yerushalmi-Rozen, T. Kerle, and J. Klein, Science. 285, 1254-1256 (1999). [3] P.C. Hohenberg and B.I. Halperin, Rev. Mod. Phys. 49, 435-479 (1977). [4] D.M. Anderson, G.B. McFadden, and A.A. Wheeler, Ann. Rev. Fluid Mech. 30,139-165 (1998). [5] U. Thiele, S. Madruga and L. Frastia. Submitted to Phys. Fluids. http://arxiv.org/abs/0707.3374 [6] S. Madruga and U. Thiele. In preparation.
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