Transient Three-Dimensional Flow Field Measurements by Means of 3D µPTV in Drying Poly(Vinyl Acetate)-Methanol Thin Films Subject to Short-Scale Marangoni Instabilities

Polymers

Philip Scharfer¹  Wilhelm Schabel¹  Max Tönsmann¹ 

[1] Karlsruhe Institute of Technology (KIT), Thin Film Technology (TFT), Kaiserstraße 12, 76131 Karlsruhe, Germany;

关键词: polymer film drying;    Marangoni number;    particle tracking velocimetry;    flow field;    convective instability;   

DOI  :  10.3390/polym13081223

来源: DOAJ

【 摘 要 】

Convective Marangoni instabilities in drying polymer films may induce surface deformations, which persist in the dry film, deteriorating product performance. While theoretic stability analyses are abundantly available, experimental data are scarce. We report transient three-dimensional flow field measurements in thin poly(vinyl acetate)-methanol films, drying under ambient conditions with several films exhibiting short-scale Marangoni convection cells. An initial assessment of the upper limit of thermal and solutal Marangoni numbers reveals that the solutal effect is likely to be the dominant cause for the observed instabilities.

【 授权许可】

Unknown