Abstract:

¹H spin-spin (T₂) relaxation times of sodium 4-decyl naphthalene sulfonate (SDNS) protons at different concentrations of 0.82 and 2.59 mmol/L were meas
ured at 298, 303 and 313 K. These T₂ values give the information about the dynamic characteristic of SDNS molecules in their monomeric and micellar states. The decrease in the T₂ values of a part of SDNS micellar protons, which participate in the formation of the palisade layer, with the increase in temperature suggests that the palisade layer becomes more tightly compact with the increase in temperature in order to prevent water penetration into the hydrophobic micellar core. While the reverse effect of the other protons in the T₂ values with the temperature up to 313 K shows that their motion of those protons is enhanced.

Key words: NMR, dynamics,  ¹H spin-spin relaxation, sodium 4-decyl naphthalene sulfonate, the palisade layer of micelle