The determination of the properties of aqueous salt solutions of poly(ethylene oxide) has been extended to the cloud point, and 8 temperature measurements have been made at several concentrations for various salts (flourides, iodides, acetates, formates, phosphates, bromides, thiosulfates and perchlorates). The resulting dependency of the critical temperatures 0 (mostly between 290 -350 K) on the molar concentration can be expressed as sequences showing the decreasing effect of anion species or cation species in salting out the polymer. The decreasing order of effectiveness of the anions in reducing the 0 temperature is PO4 > HPO4 > $203 > H2PO4 > F-> HCOO-> CH3COO-> Br-> I-. The order for cations is K § ~ Rb § ~ Na + ~ Cs + > Sr ++ > Ba § ~-Ca + § > NH~ > Li § The changes brought about in 0 temperatures by the salts were found to be the results of the changes taking place in the hydrophilic and hydrophobic interactions among polymer, solvent and additive salts and of the change of water structure by structure making or structure breaking ions, and of the influence of salts on the hydration sheath of the polymer.

The determination of the properties of aqueous salt solutions of poly(ethylene oxide) has been extended to cloud‐point and θ‐temperature measurements in sodium acetate, potassium fluoride, sodium thiosulfate, and potassium phosphate. The Hofmeister series for the decreasing effect of anion species in salting out the polymer is accordingly extended. However, the order of the effect depends on whether it is made on the basis of molar anion concentration the molar concentration of unit anion charge, or the ionic strength. Viscosity measurements on θ and non‐θ solutions containing zinc sulfate, potassium fluoride, and potassium phosphate gave polymer dimensions (in addition to limiting viscosity numbers etc.), and characteristic ratios in good agreement with theoretical predictions (Abe and Mark), and enthalpy and entropy parameters χH and χs; the latter values, nominally −0.14 and 0.63, are identical at 298 K for the three salt species.

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