Prediction of Liquid-Liquid Equilibrium for Binary Polymer Solutions with Simple Activity Coefficient Models

Phase Relationships and Thermodynamic Interactions of Isotactic Poly(1‐butene) and Organic Solvent Systems

“…The experimental solvent weight‐fraction activity coefficients at 298.15 K, Ω 2exp ∞ , presented in Table 8 are, for example, 5.83 for iPBu‐1/cyclohexane and 9.55 for iPBu‐1/benzene. These data are comparable to the literature values for polyisobutylene (PIB) at 323.2 K: 4.56 for PIB(53 000)/cyclohexane17b and 5.90 PIB(53 000)/benzene 17c. Recently it was stated17a that the infinite dilution solvent weight‐fraction‐based activity coefficients, Ω 2pred ∞ , of a polyolefin could be assumed to be constant (4.39), independent of the system, the polymer molecular weight and temperature.…”

Prediction of vapor–liquid and liquid–liquid equilibria for polymer systems: Comparison of activity coefficient models

“…Adjustable characteristic energy parameters of the various models were regressed using binary experimental LLE data available in (12) where w exp i and w cal i are experimental and calculated mass fractions, respectively, for all components. The summations are extended to the number of experimental tie lines, nexp, and to the number of components, ncomp.…”

“…The activity of the polymer is a predominant factor in LLE (liquid-liquid equilibrium) calculations for polymer solutions. A large number of equations of state and activity coefficient models capable of describing phase equilibrium in polymer solutions are available today, but only a few of these models have been tested for several different systems [9,12,13]. The studies in the literature normally focus on the residual contribution for a fixed free-volume contribution [14,15].…”

Modeling of the phase behavior of binary and ternary blends involving copolymers of styrene, methyl methacrylate and cyclohexyl methacrylate

“…In spite of this limitation, a database including temperature-dependent segmental interaction energies is expected to be valuable not only for practical reasons but also for testing new copolymer blend theories [37]. At least for mixtures of low molecular weight compounds, such a compilation has been found to be very successful [39]. In this paper, the binary interaction model with temperature-dependent v ij parameters is employed for the modeling of the phase behavior of binary and ternary blends involving copolymers of styrene (S), methyl methacrylate (MMA) and cyclohexyl methacrylate (CHMA).…”