We report an elastic-light-scattering experiment for a semidilute polymer solution under a uniform laminar shear flow. The concentration fluctuations are greatly enhanced by shear flow and their structure is highly anisotropic in both the weak (Ìd1) and strong (Ìd1) shear regimes, where Ì is the shear rate and d is the longest relaxation time of the system. The anisotropy is qualitatively different from binary liquid mixtures under a shear flow as a result of the strong coupling between the concentration fluctuations and the hydrodynamic flow.
ASJC Scopus subject areas
- Physics and Astronomy(all)