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A generalized Flory-Huggins theory for use in fitting and predicting liquid-liquid phase diagrams is presented. The parameter is defined through the chemical potential of the diluent and is represented as a product of composition-dependent and temperature-dependent terms. The former is quadratic, and the latter contains a logarithmic term in addition to the usual linear dependence on 1/T. The Koningsveld g factor is obtained by integration of the composition-dependent . Comparisons are made with experimental data, and it is shown that the functional form that is chosen for is sufficient to fit phase diagrams having a upper and lower critical solution temperatures, combination of the two with the LCST lying above the UCST, closed loop, and hourglass shapes. Such comparisons may be used to extract the temperature and concentration dependence of for the system. Both binodals and spinodals are calculated. The treatment is applicable to polymer blends as well as solutions with low molecular weight diluents.

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Molecular orientation in Langmuir-Blodgett (L-B) monolayers of poly(octadecyl methacrylate) (PODMA) and poly(octadecyl acrylate) (PODA) has been studied by infrared spectroscopy. Substantial anisotropy between the spectra measured in transmission, and by reflection at grazing incidence, was observed for both these polymers. The carbonyl group was found to be oriented approximately perpendicular to the substrate surface, independent of polymer type and of deposition surface pressure within the range investigated. The long aliphatic ester side groups were also found to be approximately perpendicular to the plane of the monolayer. However, the orientation of these groups was strongly dependent upon the chemical structure of the polymer used and on the surface pressure at transfer. More condensed L-B monolayers of PODA could be formed than was the case for PODMA, in part due to the lower steric hindrance to rotations about backbone bonds in PODA because of the absence of the methyl side group.

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