Critical polymer-polymer phase separation in ternary solutions
Abstract
We study polymer-polymer phase separation in a common good solvent by means of Monte Carlo simulations of the bond-fluctuation model. Below a critical, chain-length dependent concentration, no phase separation occurs. For higher concentrations, the critical demixing temperature scales nonlinearly with the total monomer concentration, with a power law relatively close to a renormalization-group prediction based on "blob" scaling arguments. We point out that earlier simulations and experiments have tested this power-law dependence at concentrations outside the validity regime of the scaling arguments. The critical amplitudes of the order parameter and the zero-angle scattering intensity also exhibit chain-length dependences that differ from the conventional predictions but are in excellent agreement with the renormalization-group results. In addition, we characterize the variation of the average coil shape upon phase separation.
Cite
@article{arxiv.cond-mat/0507602,
title = {Critical polymer-polymer phase separation in ternary solutions},
author = {Lei Guo and Erik Luijten},
journal= {arXiv preprint arXiv:cond-mat/0507602},
year = {2009}
}
Comments
To appear in J. Chem. Phys