Lattice–fluid model for gas–liquid chromatography

Comparison of Lattice-Fluid Binary Parameters For Mixtures and Block Copolymers

“…In spite of the controversy in the meaning of the lattice parameters k ij and l ij , we are interested in relating these parameters with the interaction parameter of Flory-Huggins, χ . [16][17][18] With this objective in mind, we compared the χ N values at the TODT app arising from the phase diagram of block copolymers predicted by Leibler (listed in Table 5) with the k ij N and l ij N values calculated by using the TODT app temperatures in the expressions of the form a + b/T obtained for k ij and l ij (Table 7). The differences between χ N LEIBLER and k ij N ( (χ N) k ), and between χ N LEIBLER and l ij N ( (χ N) l ), are plotted as a function of N in Fig.…”

“…There is some controversy in the literature concerning the relationship between the χ -parameter and the lattice-fluid binary parameters. While some authors relate the SL lattice-fluid binary parameters with the Flory-Huggins χ -parameter, [16][17][18] other authors relate the former parameters with the integral Flory-Huggins interaction parameter or residual energy of mixing, g. [11,19] In both cases, the relationship between the parameters is obtained by equating the mixing Gibbs free energy expressed through the respective theories. Callaghant and Paul [9] calculated interaction energies for each one of the binary pairs of poly(styrene) (PS), poly(methyl styrene) (PMS), and poly(methyl methacrylate) (PMMA) by fitting spinodal curves predicted by the Flory-Huggins theory and the SL equation of state to experimental cloud point data of low molecular weight polymer blends.…”

Solution Properties of C60 and C70 Fullerenes and C21 to C40 n-Alkanes at Infinite Dilution in Carbon Dioxide from Supercritical Fluid Chromatography

“…When applying eqs 4 and 5, we calculated the quantities β s T σ and α s P σ , the phase ratio V s / V m , and the slopes (∂ w 3s /∂ P ) T , σ and (∂ w 3s /∂ T ) P , σ from the Panayiotou−Vera mean-field lattice model as described before . Various kinds of mean-field lattice models have often been used to analyze the systems of interest to SFC, both without − and with ,− cosolvents. Because of the lack of either swelling or sorption data for the PMOS−CO 2 system, we used the poly(dimethylsiloxane) parameters as an estimate of the PMOS parameters in eqs 4 and 5.…”