Fig. 1.

Osmotic pressure of PEGs. Measured osmotic pressures of PEG200 and PEG3400, and their binary mixture, as described in Materials and Methods, are shown as functions of the total polymer monomer fractions. PEG200 and PEG3400 data are fit to Eq. 1; fits are shown as dashed lines. The fit to binary-mixture data were numerically calculated using the $N_s,N_b,\tilde{\alpha }$ parameters obtained from the previous fits.