Influence of acetylene bond on surface activity of acetylenic diols in aqueous solutions

Acetylenic diol surfactants, named after the carbon–carbon triple bond known as the acetylene bond, exhibit good dynamic surface tension and foam-free properties. They are widely used as wetting agents and molecular defoamers in industry and research. Although the role of the hydrophilic and hydrophobic moieties of these surfactants are well characterized, the effect of the acetylene bond on their surface activity has not yet been elucidated. To this end, herein, the chemical structure, equilibrium surface tension, dynamic surface tension, and foam properties of an alkyne free diol, SC14 diol, were analyzed and compared with those of an acetylenic diol, Surfynol 104. An increase in the rate of diffusion of the surfactant from water–air surfaces was observed when the acetylene bond existed. The performance of both diols as surfactants was discussed. The unique performance of SC14 diol surfactant enhances its potential applicability value in the field of ink and paint manufacturing.