On the determination of the surface energetics of porous polymer materials

Influence of surface modification on wettability and surface energy characteristics of pharmaceutical excipient powders

“…For all powders, contact angle values obtained from liquid penetration method (advancing contact angle) were considerably higher than those obtained with sessile drop technique (static contact angle). This difference in contact angle from two methods is also widely reported in literature (Chibowski and Hołysz, 1997;Grundke and Augsburg, 2000). Also, it has been clearly reported in literature that contact angles obtained from Washburn method are usually an overestimation of those obtained from sessile drop method for the same solids (Chibowski and Perea-Carpio, 2002).…”

Sliding variability of droplets on a hydrophobic incline due to surface entrained air bubbles

“…The average sessile drop contact angle on this was 100.9°with a standard deviation of 4.2°, consistent with previous findings [30,31]. The maximum surface peak-to-peak value and root mean squared roughness parameters of the printed sample were measured to be 15.806 lm and 3.008 lm, respectively.…”

“…The average sessile drop contact angle for droplets on this sample was 108.0°with a standard deviation of 4.7°. This is consistent with the range of values previously found [30,31]. This PTFE sample was specifically chosen for its porous surface in order to engender copious bubbles that were large enough to be observed and recorded.…”

Progress in Polypropylene Nanocomposite Development

“…Surface tension was determined by a method described elsewhere. [13] Compounding was performed with a DACA microcompounder. Some samples were prepared on a Berstorff extruder with twin screw configuration.…”

“…[12] The principle of surface tension determination on the clay powder is based on the capillary penetration of liquids into porous materials, which can be related to the wetting tension c lv cosh, where c lv is the liquid surface tension and h the contact angle. The wetting tension is then described by the following modified Washburn equation [13] c lv cosH…”