Optical measurements of frequency-dependent linear viscoelastic moduli of complex fluids

TG Mason, DA Weitz - Physical review letters, 1995 - APS
Physical review letters, 1995APS
We present a novel experimental method to measure linear viscoelastic moduli of complex
fluids using dynamic light scattering. A generalized Langevin equation is used to relate the
mean square displacement of a probe particle to the storage and loss moduli of the bulk
complex fluid. We confirm the experimental validity of this technique by comparing the light
scattering results with mechanical measurements for several complex fluids. This method
probes the moduli over a greatly extended frequency range and provides significant new …
Abstract
We present a novel experimental method to measure linear viscoelastic moduli of complex fluids using dynamic light scattering. A generalized Langevin equation is used to relate the mean square displacement of a probe particle to the storage and loss moduli of the bulk complex fluid. We confirm the experimental validity of this technique by comparing the light scattering results with mechanical measurements for several complex fluids. This method probes the moduli over a greatly extended frequency range and provides significant new insight into the elastic susceptibility of complex fluids.
American Physical Society