Virial coefficients and osmotic pressure in polymer solutions in good-solvent conditions.
We determine the second, third, and fourth virial coefficients appearing in the density expansion of the osmotic pressure Pi of a monodisperse polymer solution in good-solvent conditions. Using the expected large-concentration behavior, we extrapolate the low-density expansion outside the dilute regime, obtaining the osmotic pressure for any concentration in the semidilute region. Comparison with field-theoretical predictions and experimental data shows that the obtained expression is quite accurate. The error is approximately 1%-2% below the overlap concentration and rises at most to 5%-10% in the limit of very large polymer concentrations.
Caracciolo
Sergio
S
Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy. sergio.caracciolo@mi.infn.it
Mognetti
Bortolo Matteo
BM
Pelissetto
Andrea
A