13 research outputs found
Determination of polar and dispersive contributions of surface tensions of some macromolecular solutions
The determination of the surface tension of some liquids or solutions has been carried out using a tensiometer. The determination of the contact angle between the liquids and a planar surface has also been carried out using photography. Polar and dispersive contributions of the surface tension were obtained by calculation while the polarities of the liquids and solutions were determined applying Wu equations. This method gave the different results for solutions prepared from macromolecular compounds (acroleineethanolamine macromolecular solution 1 g/l, acroleine-diethanolamine macromolecular solution 1 g/l, acroleine-urea macromolecular solution 0.7 g/l and polyglutaraldehyde-ethanolamine macromolecular solution 1 g/) synthesized by Malonda from glutaraldehyde and acroleine. The dispersive and polar contributions of the surface tension were computed and used to calculate the surface tensions of solutions by the simple measurement of the contact angle. The results have revealed that the polarities were weak: 2% for all solutions except for the acroleine-diethanolamine macromolecular whose polarity was 6%. The surface tensions for all solutions varied from 67 to 59 dynes/cm.Keywords: Surface tension, interfacial tension, contact angle, polarity, dispersive and polar contribution