Abstract
The volume fractions of each component in the dilute phase (υ′1, υ′2, υ′3) and concentrated phase (υ1″, υ2″, υ3″) were calculated according to Flory's and Scott's theoretical equations, in the ternary system, solvent, nonsolvent, and polymers, for the polymerization degree of 1000, 5320, and ∞.
In these treatments it was assumed that P1=P2=1, P3>>1 for the polymerization degree Pi; and A=X13/P1=X31/P3=O, B=X12/P1=X21/P2=O, C=X32/P3=X23/P2≠O for the interaction parameters.
For further calculation, two cases were considered; in one, volume of the solution is kept constant by overflow of the excess solution such as in turbidimetric titration, and in the other, the whole solution is kept in a large vessel, such as in the case of the fractionation of a polymer. For these two cases, the volume fraction of the condensed phase Φ, the quantity of the precipitated polymer Φv3″, the ratio of the quantity of the precipitated polymer to the total quantity of the polymers in the system Φυ3″/υ3 were calculated as functions of the relative volume of the nonsolvents added to the system (V/V0). These treatments were made under the conditions where the interaction parameter C was 2.27 and the initial concentration υ30 was 0.0125, 0.0100, 0.0075, 0.0050, and 0.0025.
For each polymerization degree and each initial concentration, the volume of the nonsolvent, to be added to the system (V/V0)p before the precipitation starts, was also calculated.
