Multi-Responsive Wormlike Micelles Based on N-alkyl-N-Methylpiperidinium Bromide Cationic Surfactant

A noncovalent bonding method was utilized for forming multiresponsive surface-active ionic liquids in mixed N-alkyl-N-methylpiperidinium bromide (C16MDB) and potassium phthalic acid (PPA). Rheology, cryogenic-transmission electron microscopy, dynamic light scattering and nuclear magnetic resonance were used to investigate the aggregation property of surface-active ionic liquids in aqueous solution. The efficiency of the shielding effect in the form of hydrophobic effects and electrostatic attraction between PPA and the C16MDB headgroup under diverse pH conditions is found to be the root cause of a shift in the aggregate's morphological transformation. In addition, the molecular motion of surfactant molecules becomes more active as the temperature increase provides the property of thermoresponsive to the surface-active ionic liquid system.