Measuring the Equilibrium Spreading Pressure-A Tale of Three Amphiphiles.

ABSTRACT: A surfactant's equilibrium spreading pressure (ESP) is the maximum decrease in surface tension achievable at equilibrium below the Krafft point. Difficulties in measuring the ESP have been noted previously but no well-established experimental protocols to overcome them exist. We present a case study of three solid amphiphiles with different propensities to spread on the air-water interface. Starting with the partially water soluble n-dodecanol (C₁₂H₂₅OH), which spreads instantaneously. The strong Marangoni flows associated with the spreading result in the dislocating of the Wilhelmy plate or crystals attaching to it. A temporary mechanical barrier in front of the spreading crystals mitigates the flows disturbing the plate. Presaturating the subphase with the amphiphil

SUBMITTER: Peychev B 

PROVIDER: S-EPMC11396376 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature