Polar solvation dynamics in nonionic reverse micelles and model polymer solutions

The effect of confinement on solvation dynamics has been explored in Brij-3 0/cyclohexane and Triton X-100/cyclohexane nonionic reverse micelles. Insid e the reverse micelles, the polar solvation dynamics became slower and show additional slow relaxation modes not observed for bulk water. The solvatio n dynamics inside the Triton X-100 reverse micelles is slower than the dyna mics inside Brij-30 reverse micelles. The results for solvation dynamics in the reverse micelles contrast solvation dynamics in aqueous tri(ethylene g lycol) monoethyl ether solutions comparable to the reverse micellar interio rs, which show significantly faster response. Measurements in the nonionic reverse micelles are also compared to previous work on ionic reverse micell es. Results reported here show that the interactions of water with the poly oxyethylene ether, as well as the micellar confinement inside these reverse micelles, effectively immobilize the water in the micellar interiors.