A comparison of miscible binary blend interaction parameters measured by different methods

Miscible blends of the polyhydroxy ether of bisphenol‐ A , Phenoxy, with a series of aliphatic polyesters were studied using melting point depression analysis and sorption to obtain the Flory‐Huggins polymer‐polymer interaction parameter, B . The B values obtained from these measurements were found to agree well in sign, magnitude, and variation with ester repeat structure and to also agree well with B values measured calorimetrically for mixtures of low molecular weight compounds with structures which are analogous to those of the polymers. These comparisons suggest that the same mechanisms are responsible for the exothermic heats of mixing measured directly for the analog compounds and indirectly for the miscible polymer blends. For this general system, evidence is provided which suggests that hydrogen bond formation between the hydroxyl group on Phenoxy and the ester moiety is probably responsible for the exothermic interactions and polymer blend miscibility observed.