ABSTRACT

Membranes are thin sheets of synthetic or natural material that can be made selectively permeable. During the past few decades, membranes have been used for performing increasingly complex material separations. The number of potential uses for membranes has risen due to improved manufacturing, which includes reducing the membrane thickness, producing more defect-free materials, and introducing nano-sized fillers to form nanocomposites. That is, nanocomposites are hybrid composite materials consisting of a polymer matrix with dispersed nanoparticles. Furthermore, nanocomposite membranes

CONTENTS 14.1 Introduction ........................................................................................................................ 413 14.2 Factors Affecting Permeation ........................................................................................... 414

14.2.1 Temperature ............................................................................................................ 414 14.2.2 Permeant ................................................................................................................. 415 14.2.3 Polymer Structure .................................................................................................. 416 14.2.4 Mechanical Deformation ...................................................................................... 417

14.3 Factors Enhancing Gas Barrier Properties ..................................................................... 419 14.3.1 Exfoliation ............................................................................................................... 419 14.3.2 Compatibility ..........................................................................................................420 14.3.3 Orientation ..............................................................................................................420 14.3.4 Reaggregation .........................................................................................................420

14.4 Theoretical Modeling ........................................................................................................420 14.4.1 Limiting Cases ....................................................................................................... 424