The Doi-Shimada-Okano [J. Chem. Phys. 88, 4070 (1988)] theory of the spinodal decomposition in a suspension of rods is reinvestigated analytically. Short enough rods may rotate fairly unhindered so we emphasize translational diffusion. The excluded-volume effect between the rods gives rise to a coupling of the orientational and translational degrees of freedom. This effect may be addressed correctly because the kernel in the equation describing the dynamic evolution of the one-particle distribution turns out to be degenerate. The two principal eigenvalues calculated analytically agree with previous numerical work by Maeda [Macromolecules 22, 1881 (1989); 23, 1464 (1990)]. It is concluded that the associated relaxation modes do not represent pure density and orientation fluctuation modes.
|Journal||Physical Review E - Statistical, Nonlinear, and Soft Matter Physics|
|Publication status||Published - 2001|