Frequency-domain electric birefringence study on the deformation dynamics of microemulsion droplets

COLL 153

Takeshi Shimomura and Kohzo Ito. Graduate School of Frotier Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
Electric birefringence has been applied widely to solutions of polymers, micelles and colloids in order to investigate the microscopic electro-optical properties closely related to the conformation and polarization of molecules. Further, a time-dependent electric field yields electric birefringence relaxation, which provides information on the dynamic behavior of molecules, such as molecular rotation, deformation and polarization. So we applied the frequency-domain electric birefringence (FEB) method to deformable droplets in order to investigate their deformation dynamics. At first, we derived theoretically the second-order nonlinear response function from the diffusion equation of the deformable droplet with induced dipole moment. Further, we applied this formula to the experimental results obtained by the FEB method for water/AOT/isooctane (w/o) microemulsion system (L2 phase) and obtained the bending modulus of the amphiphilic layer, which plays an important role in the stability of the microemulsion structure.
 

Colloidal and Molecular Electro-Optics

Division of Colloid and Surface Chemistry
The 225th ACS National Meeting, New Orleans, LA, March 23-27, 2003