Synergistic interaction of α-olefin sodium sulfonate/cocamidopropyl betaine surfactant mixtures and preparation of wormlike micelles

Abstract

The unique structure and macro-rheological properties make worm-like micelles an important basic system for surfactant applications, which are widely used in many fields and have received extensive attention from researchers. In this paper, α-olefin sodium sulfonate (AOS) and cocamidopropyl betaine (CAPB) were mixed in aqueous solution to prepare viscoelastic worm-like micelles, which can be observed by cryogenic-transmission electron microscopy (cryo-TEM). It was found that the concentration of AOS and temperature have a greater impact on the formation and rheological behavior of worm-like micelles. The typical characteristics of wormlike micelles were shown in the range of AOS concentration from 0.7 wt% to 1.7 wt%; when the temperature was too high, the worm-like micelles were destroyed. In addition, the surface tension, foaming property and wettability of AOS/CAPB mixed solutions with different ratios were studied. The two show excellent synergistic effect, in which electrostatic interaction is the decisive factor, which can provide basic data for practical applications. This work further enriches the basic theoretical research on the preparation of worm-like micelles from anionic-zwitterionic surfactant systems.