Estimation of the Polar Surface Tension Parameters of Glycerol and Formamide, for Use in Contact Angle Measurements on Polar Solids

By measuring contact angles with water, glycerol and formamide on a number of polar surfaces, an estimate could be made of the electron-acceptor (γ+ ) and the electron-donor (γ− ) parameters of glycerol (G) and formamide (F), relative to the parameters of. water (W), for which a reference value of γ+ W = γ− W = 25.5 mJ/m2 has been assumed. The values thus found are: γ+ G ≈ 3.92 mJ/m2 (which yields γ− G ≈ 57.4 mJ/m2) and γ+ F ≈2.28 mJ/m2 (which yields γ− F ≈ 39.6 mJ/m2).