Projects per year
There has been an increasing interest in the recent years from industries that deal with polymeric materials (e.g. producing paints, polymeric fibers etc.) for powerful thermodynamic tools. These tools should free them from costly and time-consuming experiments, losses of chemicals due to inaccurate process design, or errors in prediction of phase equilibria whenever a change in the process -either in the temperature or pressure, or in the number and type of the components- is required. The target of this thesis is to evaluate and develop such thermodynamic tools, in terms of activity coefficient models or equations of state, capable of describing qualitatively – and to a high extend quantitatively – vapor-phase and liquid-phase equilibria of multicomponent polymer systems containing non-polar, polar and associating solvents. With this focus, the free-volume term of the Entropic-FV activity coefficient model has been modified based on the performance of the model in athermal systems with high asymmetry (high differences in molecular size). The applied modification corrects the underestimation of the original Entropic-FV model in the prediction of activity coefficients of both solvent and solute and can be theoretically justified by the values of packing densities of polymers and organic solvents, based on their geometrical structure. Furthermore, the simplified PC-SAFT equation of state has been evaluated in more demanding areas of industrial interest, such as polymers with complex structure (nylons), and systems containing components that self- and cross-associate. Special attention has been given in two points: a) the development of an efficient algorithm for the calculation of liquid-liquid equilibria in polymer systems and b) the regression of the pure-polymer parameters that are required as input from simplified PC-SAFT. The overall performance of the simplified PC-SAFT equation of state in the studied cases is quite promising and is our wish that the present thesis will provide the ground for further improvement and development of the model.
|Place of Publication||Kgs. Lyngby|
|Publisher||Technical University of Denmark|
|Number of pages||146|
|Publication status||Published - Apr 2004|
Kouskoumvekaki, E., Kontogeorgis, G., Michelsen, M. L., Mollerup, J., Voutsas, E. C. & Dahl, S.
01/02/2001 → 22/04/2004