We measured the line tension of the air/hexadecane/aqueous solution of the dodecyltrimethylammonium bromide (DTAB) system as a function of the molality of DTAB aqueous solution at 298.15 K. The experimental values of the line tension were 10-10 to 10-12N, and they coincided with the theoretical estimates. Furthermore, it was found that the line tension changes in sign from positive to negative at around 0.750 mmol kg-1. This concentration is close to the point of transition from partial to frustrated-complete wetting. Taking into account the profiles of the free energy of the air/water surface, previously developed by Indekeu to understand the interrelationship between the wetting transition and line tension, it is suggested that the sign reversal of the line tension can be attributed to the transition from partial to frustrated-complete wetting.
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Polymers and Plastics
- Colloid and Surface Chemistry
- Materials Chemistry