Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Article Citation - WoS: 8Citation - Scopus: 8Phase Equilibrium and Diffusion of Solvents in Polybutadiene: a Capillary-Column Inverse Gas Chromatography Study(John Wiley and Sons Inc., 2002) Cai, W. D.; Tıhmınlıoğlu, Funda; Tıhmınlıoğlu, Funda; Danner, Ronald P.; Duda, John Larry; De Haan, A.; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyThe capillary-column inverse gas chromatography method was used to measure the diffusion and partition coefficients of ethylbenzene, styrene, and acrylonitrile in polybutadiene (PBD) at infinite dilution of the solvents. Experiments were performed over a temperature range of 50-125°C. At temperatures well above the glass-transition temperature of PBD, the diffusivities were correlated using an Arrhenius expression. The Arrhenius parameters in turn were intercorrelated and shown to be a function of the occupied volume, thus providing a method for predicting the diffusion of other solvents in the same polymer. Further, the activation energy was predicted using the Duda-Vrentas free-volume approach. The activation energy thus obtained was compared with the activation energy of the Arrhenius approach. The weight-fraction activity coefficient data were compared to the predictions of the group contribution, lattice-fluid equation-of-state, and the UNIquac Functional-group Activity Coefficient (UNIFAC) free-volume models.Article Citation - WoS: 13Citation - Scopus: 15Determination of Thermodynamic and Transport Properties of Solvents and Non Solvents in Poly(l-Lactide(John Wiley and Sons Inc., 2006) Eser, Hülya; Tıhmınlıoğlu, Funda; Tıhmınlıoğlu, Funda; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyThermodynamic properties, partition coefficient, and diffusion coefficients of the various solvents (acetone, dichloromethane, trichloromethane, ethyl acetate, ethyl alcohol, tetrahydrofuran, and water) in poly(lactide-co- glycolide) (PLGA) at infinite dilution of the solvent have been determined by inverse gas chromatography (IGC). In IGC method, which is based on the characteristic equilibrium partitioning of a solute between a mobile phase and a stationary phase, a small pulse of solvent is introduced into the column and by the aid of retention volume of the solvent, several polymer solvent interaction properties, namely retention volume (Vg), infinitely dilute weight fraction activity coefficient (Ω1∞), Flory-Huggins interaction parameter (χ), and solubility parameters of the polymer (δ2∞) can be determined. The thermodynamic results indi cated that trichloromethane and dichloromethane were the most suitable solvents among all the solvents studied for PLGA. The partition (K) and diffusion coefficients (Dp) of various solvents at infinite dilution of the solvent were calculated by using the model developed by Pawlisch et al. (Macromolecules 1987, 20, 1564). The optimum K and D p values that best fit the data were found and the model predicted experimental data very well. So IGC method is a powerful tool for the determination of thermodynamic and diffusion properties of solvent in polymer at infinite dilution of the solvent.Article Citation - WoS: 21Citation - Scopus: 26Solubility and Diffusivity of Solvents and Nonsolvents in Poly(methyl Methacrylate Co Butyl Methacrylate)(Elsevier Ltd., 2005) Eser, Hülya; Tıhmınlıoğlu, Funda; Tıhmınlıoğlu, Funda; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyLocate full-text(opens in a new window)|Full Text(opens in a new window)|View at Publisher| Export | Download | Add to List | More... Fluid Phase Equilibria Volume 237, Issue 1-2, 25 October 2005, Pages 68-76 Solubility and diffusivity of solvents and nonsolvents in poly(methyl methacrylate co butyl methacrylate) (Article) Eser, H., Tihminlioglu, F. Department of Chemical Engineering, Izmir Institute of Technology, Gulbahce Urla- Izmir 35430, Turkey View references (25) Abstract In this study, thermodynamic properties, namely retention volume, infinitely dilute weight fraction activity coefficient, Flory-Huggins interaction parameter, solubility parameter of the polymer, partition coefficient and diffusion coefficients of the various solvents in poly(methyl methacrylate co butyl methacrylate) (PMMA co BMA) at infinite dilution of the solvent have been determined by inverse gas chromatography (IGC). In this technique, a small amount of the solvent was injected into the capillary column and its retention time was measured and used to calculate several polymer-solvent interaction parameters which are mentioned above. The solvents used in this study were methanol, ethanol, propanol, butanol, methyl acetate, ethyl acetate, propyl acetate, dichloromethane, trichloromethane, acetone, methyl methacrylate, butyl methacrylate for PMMA co BMA. The thermodynamic results, obtained from the experiments, indicated that trichloromethane and dichloromethane were the most suitable solvents among all the solvents studied for PMMA co BMA. The partition (K) and diffusion coefficients (Dp) of various solvents at infinite dilution of the solvent were calculated by using the model developed by Pawlisch et al. [C.A. Pawlisch, A. Macris, R.L. Laurence, Solute diffusion in polymers.1. The use of capillary column inverse gas chromatography, Macromolecules 20 (1987) 1564-1578]. The optimum K and D p values that best fit the data were found and the model predicted experimental data very well. Vrentas-Duda free volume theory was used to correlate the diffusion data and to investigate the effect of solvent size on diffusion process. The theory has shown to correlate diffusion data above the glass transition temperature very well for the PMMA-co-BMA-solvent system.Article Citation - WoS: 18Citation - Scopus: 22Application of Inverse Gas Chromatography To the Measurement of Diffusion and Phase Equilibria in Polyacrylate-Solvent Systems(Elsevier Ltd., 1999) Tıhmınlıoğlu, Funda; Tıhmınlıoğlu, Funda; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyThe inverse gas chromatography technique (IGC) was used to determine the partition and diffusion coefficients of ethyl acetate and 2-ethylhexyl acrylate in polyacrylate for both infinite dilution and finite concentrations of solvent. Experiments were performed over a temperature range of 60 to 100°C, more than 100°C above the glass transition temperature of the polymer. The capillary column IGC model previously developed for determining partition and diffusion coefficients of infinitely dilute solvent has been modified to account for the concentration of the solvent in the polymer phase. Thermodynamic data obtained from retention theory and the modified capillary column IGC model are compared