Solvent H/D isotope effects on miscibility and Θ-temperature in the polystyrene–cyclohexane system

Influence of the Solvent Quality on Ring Polymer Dimensions

“…Isotopic changes due to solvent alteration from h 12 -cyclohexane to its d 12 -analogue lead to an experimental temperature increment of 3.8 °C, i.e., a θ -temperature of linear PS of 38.3 °C. 24 This increment, which depends slightly on molecular weight, was also estimated by Siporska et al, 21,25 who found a similar value, as 3.5 °C. Hence, entirely on the basis of experimental facts, 24 we estimate the θ -temperature of the R161 PS ring to be 31.5 ± 1 °C (i.e., close to the extracted value of 35 ± 1 °C for R14 which exhibits a broader θ -range due to the lower molecular weight).…”

Miscibility of 1-alkyl-3-methylimidazolium bis(trifluoromethyl)sulfonyl imides with benzene and deuterated benzene

“…This behaviour is well understood taking into account the large asymmetry in the molecular weights of both components. The same behaviour was observed for hydrocarbon/acetone [13] and polymer/organic solvents systems [14]. However further shortening the chain, i.e.…”

“…There is no theory that could satisfactorily explain the origin of such a high isotope effect on miscibility (in this case ΔT c reaches 50 K). The theory of the condensed phase isotope effects originally formulated by Bigeleisen [21] and then developed by Van Hook [22] and Rebelo [14,23] for liquid-liquid phase equilibria was successfully applied to the several systems, e.g. polystyrene/cyclohexane [14] or 1-butyl-3-methylimidazolium tetrafluoroborate/water [24], to explain the sign and magnitude of observed isotope effects.…”

Solubility of polystyrene in selectively deuterated methyl acetate

“…As was shown previously2–4 miscibility isotope effect on the critical point is related with the frequency shifts of the isotope dependent vibrational modes on transfer from pure liquid to solution at infinite dilution. In most cases the contribution coming from the stretching vibrations dominates.…”