In this study, thermodynamic properties, namely retention volume, infinitely dilute weight fraction activity coefficient, Flory- Huggins interaction parameter, solubility parameters of solute and polymer, partition coefficient and diffusion coefficients of the various solvents in poly (methyl methacrylate co butyl methacrylate) (PMMA co BMA) and poly (lactide co glycolide) (PLGA) 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 solutes used in this study were methanol, ethanol, propanol, butanol, methyl acetate, ethyl acetate, propyl acetate, dichloromethane, trichloromethane, acetone, methyl methacrylate, butyl methacrylate, water for PMMA co BMA and acetone, dichloromethane, trichloromethane, ethyl acetate, ethyl alcohol, tetrahydrofuran, water for PLGA. The glass transition temperature of the polymers were determined as 106 0C and 42 0C for PMMA co BMA and PLGA respectively by differential scanning calorimetry. Experiments were performed in the range of 150-200 0C for PMMA co BMA and 80-120 0C for PLGA which are above the glass transition temperature of the polymer. The thermodynamic results, obtained from the experiments, indicated that trichloromethane and dichloromethane were the most suitable solutes among all the solvents studied for both of the polymers. 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. (1987). The optimum K and Dp values that best fit the data were found and the model predicted experimental data very well. In summary, IGC method is a powerful tool for the determination of thermodynamic and diffusion properties of solvent in polymer at infinite dilution of the solvent. 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.

A proper understanding of diffusion and mass transfer theory is critical for obtaining correct solutions to many transport problems. Diffusion and Mass Transfer presents a comprehensive summary of the theoretical aspects of diffusion and mass transfer and applies that theory to obtain detailed solutions for a large number of important problems. Par

This work introduces the fundamental background necessary to understand polymer devolatilization. It elucidates the actual mechanisms by which the devolatilization of polymer melts progresses, and discusses virtually every type of devolatilization equipment available. The work also addresses devolatilization in various geometries and types of equipment, describing the use of falling strand, slit, single-screw, co-rotating and counter-rotating twin-screw devolatilization.

This NATO ASI involved teachings and perspectives of the state-of-the-art in experimental and theoretical understandings of transport in nanoporous solids. This workshop brought together the top scientists and engineers in each area to discuss the similarities and differences in each technique and theory. The lectures truly bridge the gaps between these related areas and approaches. The applications in future separations, catalysis, the environment and energy needs are obvious. The solids comprised the newly developing molecular sieves, biological systems and polymeric solids. Transport in single particles, in membranes and in commercial applications were reviewed and analyzed, placing each in context. Techniques such as uptake, Chromatographic, Frequency Response, NMR, Neutron Scattering and Infrared spectroscopies are discussed for mixtures as well as for single components. Theoretical approaches such as Density Functional Theory, Statistical Mechanics, Molecular Dynamics and Maxwell-Stefan Theory are employed to analyze the diffusional transport in confined environments, spanning from sub-nanometers to centimetre scales. In all cases the theories are related to the experiments. These lectures present a uniquq opportunity to learn the various theoretical and experimental approaches to analyze and understand transport in nanoporous materials.