| Abstract
| - We examined the dynamics of amphiphilic polymer micelles of the diblock copolymer HOVE-NBVE(hydroxyethylvinyl ether as a hydrophilic segment and n-butylvinyl ether as a hydrophobic segment) inaqueous solution using the neutron spin−echo (NSE) technique. The time-correlation function obtainedfor the polymer micelles was well fitted by double exponential function, and the fast and slow modes couldbe estimated separately. The slow mode was dominant at smaller scattering angles, and showed an excellentlinearity in Γ(decay rate) vs q2 (scattering vector) plot. The diffusion coefficient evaluated from its slopeand the hydrodynamic radius, Rh, by the Einstein−Stoke equation were consistent with the size of thepolymer micelle that was estimated by small-angle neutron scattering (SANS), small-angle X-ray scattering(SAXS), and dynamic light scattering (DLS). Hence, this slow mode reflects the translational diffusion ofthe polymer micelle in aqueous solution. The fast mode, which was 1 order of magnitude faster than theslow mode, was a major factor for larger scattering angle regions in which the SANS curve showed blobscattering. Thus, the fast mode appears to be an internal motion of the polymer micelle, like the breathingmode of the hydrophilic shell (corona) around the polymer micelle.
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