Numerical self-consistent field study of tethered chains in Θ solvent

We present a numerical, self-consistent field (SCF) study of tethered polymers in Theta solvent, over the range of anchoring densities found in most experiments. We examine the properties of the dangling block, including the thickness of the brush, the density profile, the depletion layer, the maximum polymer concentration and its location, and the dependence of these properties on surface density and molecular weight. In the calculations, the polymer and solvent are characterized by realistic values of the pure component densities, the statistical segment length, and the Flory interaction parameter, and we make quantitative comparison with recent experiments [M. S. Kent, G. S. Smith, J. Majewski, L. T. Lee, and S. Satija, J. Chem. Phys. 108, 5635 (1998)] and with the asymptotic analytic SCF theory. In agreement with these experiments, our results add to the growing body of evidence that many of these systems are not well described by the asymptotic theories. (C) 1998 American Institute of Physics.