Ecofriendly Viscoelastic Solutions Formed from a Recyclable Rosin-Based Amine Oxide Surfactant.

Innovations in molecular structures formed using bioresources are efficient means to prepare surfactant aggregates with unique properties. Here, a rosin-based amine oxide surfactant () containing large hydrophobic groups was synthesized from rosin derivatives, namely, dehydroabietic acid and long-chain amino acids. Cryo-transmission electron microscopy showed that molecules formed extremely long wormlike micelles with a cross-sectional diameter of 4-5 nm at a concentration of approximately 7 mmol·L. A gel-like system was obtained at approximately 30 mmol·L due to the dense entanglement of the wormlike micelles. The solutions also exhibited unique shear thickening behavior at a shear rate of approximately 10 s even at high concentrations. The large hydrophobic group contained in is the origin of the strong van der Waals interactions between the surfactant molecules, resulting in the rapid growth of wormlike micelles. This rosin-based surfactant is the first recoverable amine oxide surfactant from solutions through the salting-out effect with high recovery rates. This work demonstrates the unique capabilities of rosin-based surfactants for forming wormlike micelles and provides opportunities for the development of surfactant recovery technologies.