Diffusion of Electrolytes in Polymers

Preface CHAPTER 1. GENERAL ASPECTS OF DIFFUSION IN POLYMERS Generalized form of the continuity equation for mass transfer The choice of characteristic velocities and fluxes in different reference systems Different formulations of Fick's law Description of diffusion in terms of the thermodynamics of irreversible processes Application of the theory of absolute velocities to diffusion The free volume theory The mathematics of diffusion CHAPTER 2. CHARACTERISTICS OF ELECTROLYTE DIFFUSION IN POLYMERS Fundamental concepts: a thermodynamic approach The electrodiffusion equation for ion transport Membrane potentials Phenomenological theory of electrolyte diffusion in polymers Effect of external mass transfer on electrolyte diffusion in polymers CHAPTER 3. WATER DIFFUSION Water structure Effect of solute molecules on the water structure Water diffusion in polymers Abnormal water diffusion in polymers CHAPTER 4. ELECTROLYTE DIFFUSION IN HYDROPHILIC POLYMERS Diffusion theories taking into account the volume content of the polymer Structural aspects of diffusion in hydrophilic polymers Electrolyte state in polymers Diffusion mechanisms in hydrophilic polymers The effect of electrolyte concentration on diffusion coefficients CHAPTER 5. DIFFUSION OF ORGANIC AND INORGANIC ACIDS IN MODERATELY HYDROPHILIC POLYMERS Models of acid sorption by polyamides Concentration dependence of the ion diffusion coefficients in polymers The site saturation model The use of the site saturation model for an explanation of the concentration dependence of the diffusivities of individual ion species Sorption of weak organic acids by polyamides Diffusion and sorption of concentrated electrolytes (amide region) CHAPTER 6. ELECTROLYTE DIFFUSION IN HYDROPHOBIC POLYMERS Investigation methods Effect of different factors on unsteady diffusion Steady-state diffusion CHAPTER 7. ELECTROLYTE SOLUBILITY IN POLYMERS Generalized definition of solubility. Thermodynamic aspects Hydrophobic polymers Intermediate (moderately swelling) polymers Hydrophilic polymers CHAPTER 8. DIFFUSION AND CHEMICAL REACTIONS lntroduction Methodology of chemical degradation studies Accessibility of polymer functions to molecule sorption Examples of the use of accessibility parameters in some experimental calculations Kinetics of isotope exchange in solid polymers Kinetics of polycaproamide degradation in hydrochloric acid CHAPTER 9. SOME METHODS OF INVESTIGATION OF ELECTROLYTE DIFFUSION IN POLYMERS Introduction Isotope exchange Sorption technique Electrical conductivity measurements Permeability of polymer membranes CHAPTER 10. SOME PRACTICAL ASPECTS OF ELECTROLYTE DIFFUSION IN POLYMERS Effect of electrolyte diffusion on polymer degradation Preparative introduction of electrolytes into a polymer Electrolyte diffusion in separation processes Dialysis and release of drugs and/or physiologically active agents Protein diffusion and absorption.