Estimation of χ Parameters from Phase Diagrams

We estimated the χ parameter using the Flory-Huggins theory and cloud point data [1] from PS/PB miscible systems, as shown in the UCST phase diagrams. In this case, the χ parameter concentration dependency is a weak system, so the χ parameter was simplified with the following expression.

Figure 1 shows the estimation results. The axis represents the PS volume fraction, and the Y-axis represents temperature. By entering the experimental values in this manner, we were able to obtain a coexistence curve and a spinodal curve.

Figure 1. Coexistence Curve and Spinodal Curve of Experimental Data