Micellar Behaviour of a Nonionic Surfactant, Surfynol 465, from 1H-NMR Chemical Shifts in D2O

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Authors

  • Division of Physics, Nagoya City University, Tanabe-Dori 3-1, Muzuho-Ku, Nagoya, 467 ,JP
  • Division of Physics, Nagoya City University, Tanabe-Dori 3-1, Muzuho-Ku, Nagoya, 467 ,JP

DOI:

https://doi.org/10.18311/jsst/1988/2341

Keywords:

Surfynol 465, 1H-NMR, Chemical Shift, Miscelle Formation, Overlapping Model, Miscellar Interaction.

Abstract

1H-NMR spectra of a nonionic surfactant, Surfynol 465, in D2O were measured and assigned at various Concentrations. Signals from all protons did not seperate into multiple and shifted to downfield with the increase of Concentration. Taking into consideration that the surfactant molecule exchanges rapidly between monomeric and micellar phases and each observed signal takes a weight-average position between those corresponding to both phases, we analyzed the chemical shift as a function of molality of molality of surfactants on the basis of the overlapping model, which was previously proposed to the analysis of thermodynamic properties of Surfynol 465. The fitness of theoretical to experimental values was found up to 3 mol kg-1 for surfactant concentration. At higher concentrations, some sort of phase transition is suggested. Specific behaviours of various protons at different positons in the surfactant molecule were found on the magnitude of their downfield shifts at the micelle formation and the interaction among micelles.