Thermodynamics of Polymer Compatibility in Ternary Systems

Phase‐separation phenomena in solutions of poly(2,6‐dimethyl‐1,4‐phenylene oxide). I. Thermodynamic parameters of solutions in toluene

“…A final comparison with other data is possible for the ternary system PPO/polystyrene/toluene where no liquid-liquid phase separation 0ccurs.l Hence it can be expected that the interaction between PPO and toluene is not very different from that between polystyrene and toluene. 20 Indeed the x parameters found for polystyrene-toluene6 are of the same magnitude as the values for PPO-toluene found in this work. This supports our conclusion that the phase-separation phenomenon observed for PPO-toluene is a crystallization phenomenon and not a liquid-liquid phase separation.…”

Construction of ternary phase diagrams in nonsolvent/solvent/PMMA systems

“…in his work) indicate that the system with larger Larger binary interaction parameters indicate g 12 (fixed x 13 and g 23 ) has a smaller demixing gap low compatibility between components. Thereand the system with larger x 13 (fixed g 12 and g 23 ) fore, according the results shown in Table I, we has a larger demixing gap. The results obtained can deduce that the miscibility between nonsolfrom the numerical code presented in this work vent and solvent follows this order: n-hexane/ncompletely agree with the above rule.…”

“…for the dependence of g 23 16 and Boom et al 17 expressed g 23 in without using any penalty function. 23 The searchterms of n 3 , the volume fraction of polymer on ing for a minimum value was accomplished by a nonsolvent-free basis. In this section we only using a subroutine DBCLSF in the IMSL library present the equilibrium equations (eqs.…”

“…These procedures were repeated To obtain the equilibrium binodal curve and tie till the criterion (Éf 3b,old 0 f 3b,new É õ 10 06 ) was lines by the procedures described above, three bimet. nary interaction parameters g 12 , g 23 , and x 13 need to be known first. In the present work, nonsolvent/solvent interaction parameters ( g 12 ) were EXPERIMENTAL calculated by using the data of excess Gibbs free energy 18 or activity coefficients 19 available in litMaterials erature.…”

On the one‐phase state of aqueous protein‐uncharged polymer systems: Casein‐guar gum system

“…Let us consider the effect of ionic strength on the phase state from the point of view of the general theoretical concepts relative to the relations between the intensity of polymer-solvent and polymerpolymer interactions, and the phase state of polymer/polymer/solvent systems. 2,50,51 Compatibility between caseinate and guar in water at low ionic strength when the pH is above the isoelectric point of casein can be ascribed to two causes: the formation of weak soluble interpolymer complexes, which dissociate when ionic strength rises; and/or the vanishing of the difference in the thermodynamic interaction parameter between each of the biopolymers and water. The second one seems unlikely, because caseinate is thermodynamically incompatible with PEG in the absence, as well as in the presence, of salt (Fig.…”