Abstract
This work reports data showing the evolution of contact angle with time for mixtures of water and 1-propanol at room temperature on poly(methyl methacrylate) (PMMA). The composition range investigated spans the azeotropic composition, thus encompassing systems containing excess water and excess 1-propanol. A discontinuity in the contact angle behavior is observed and it is suggested that this enables the identification of the azeotropic composition as 0.39 mole fraction of 1-propanol. This suggestion is supported by boiling point measurements made at around 20 mmHg. The discontinuity is associated with the presence of an instability, which causes a distortion around the droplet perimeter. It is suggested that the distortion is caused by competing effects of local surface tension maxima and minima.
| Original language | English |
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| Pages (from-to) | 8217-8220 |
| Number of pages | 4 |
| Journal | Journal of Physical Chemistry B |
| Volume | 104 |
| Issue number | 34 |
| DOIs | |
| Publication status | Published - 31 Aug 2000 |