The CO₂ stimulus-responsive spherical-worm-like micelles transition based on anionic surfactant sodium oleate and N, N, N′, N′, N″-pentamethyldipropylenetriamine

ABSTRACT

Here, we report a CO₂ stimulus-responsive system with anionic surfactant sodium oleate (NaOA) and N, N, N′, N′, N″-Pentamethyldipropylenetriamine (PMDPTA). The microstructure transition from spherical micelles to worm-like micelles was confirmed by rheology measurements, dynamic light scattering (DLS), and cryogenic transmission electron microscopy (Cyro-TEM). There were three types of CO₂₋responsive groups in PMDPTA. However, because of PMDPTA ionization degrees, just one responsive group of PMDPTA could be ionized by CO₂ to work with OA⁻, resulting in structure transformation from spherical micelles to worm-like micelles. Besides, this system could be switchable between low-viscosity fluid and high viscoelastic by CO₂/N₂.

GRAPHICAL ABSTRACT

KEYWORDS:

• Anion surfactant
• CO₂ stimulus responsive
• spherical-worm-like micelles

Acknowledgments

This work was supported by the Engineering Research Centre of Oilfield Chemistry, Ministry of Education Key.