Solvation dynamics of TNS in polymer (PEG)–surfactant (SDS) aggregate

Solvation dynamics of 2,6-p-toluidinonaphthalene sulfonate (TNS) is studied using picosecond time resolved emission spectroscopy in a polymer–surfactant aggregate consisting of polyethylene glycol (PEG) and sodium dodecyl sulfate (SDS). The critical association concentration (CAC) of SDS for PEG, is found to be 4.5±0.5 mM. Solvation dynamics of TNS in PEG–SDS aggregate is described by two components, 90±10 ps (31%) and 570±50 ps (69%). Solvation dynamics in PEG–SDS aggregate is slow compared to that in bulk water or in PEG alone or in SDS alone indicating restricted movement of the water molecules squeezed in between the polymer chains and the micellar (SDS) surface.