Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 38 for “"polymer membranes"”.
-
Transport and Anisotropy inside Ionic Polymer Membranes
… and molecular interactions inside ionic polymers. I first discuss a main deficiency of a standard protocol for calibrating high pulsed-field-gradient NMR. I show that high gradient calibration using low γ nuclei is not amenable to measurements on slow diffusing high γ nuclei. Then I …
-
Novel conducive alkaline polymer membranes for fuel cells
A series of anion exchange membranes synthesised from poly (2, 6-dimethyl-1, 4-phenylene oxide) (PPO) have been investigated for water electrolysis applications. The prepared membranes were characterised using electrochemical impedance spectroscopy, infrared spectroscopy and thermal gravimetric …
-
Transition metal ion coordination in hydrophilic polymer membranes
… metal ion complexation within hydrophilic copolymer membranes. The membranes are copolymers of 4-methyl-4'-vinyl-2,2'-bipyridine, the 2-hydroxyethyl ester of 4,4'- dicarboxy-2,2'-bipyridine & bis-(5-vinylsalicylidene)ethylenediamine with 2-hydroxyethyl methacrylate. The effect of the polymer …
-
Surface modification of polymer membranes by self-organization
Water filtration processes employing polymer membranes have become increasingly important over the past forty years. Due to their high efficiency and modularity relative to conventional processes, membrane separations are among a suite of emerging water treatment technologies which will make …
-
Temperature effects on sorption and permeability of different polymer membranes
Includes bibliographical references (pages 83-88).
-
The separation of hydrogen and carbon monoxide using polymer membranes
This work studies the development of polymer membranes for the separation of hydrogen and carbon monoxide from a syngas produced by the partial oxidation of natural gas. The CO product is then used for the large scale manufacture of acetic acid by reaction with methanol. A method of economic …
-
Free Volume Manipulation Techniques of Polymer Membranes for Gas Separations
… Using non-thermally-driven processes, such as polymer membranes, for gas separations could reduce energy costs by up to 90% and save the United States over 4 billion USD per year. Recently, polymers of intrinsic microporosity (PIMs) have shown promise as a platform for energy-efficient gas …
-
Elucidating the Role of Fluorine on Gas Transport Through Fluorinated Polymer Membranes
Fully fluorinated polymers (i.e., perfluoropolymers) are a unique class of materials that have shown exceptional separation performance due to their anomalous thermodynamic partitioning compared to typical hydrocarbon polymers. The goal of this work is to elucidate the role of fluorine on gas …
-
Leveraging Competitive Sorption in Microporous Polymer Membranes to Enhance Gas Separation Performance
… phase changes to operate. Specifically, polymer membranes with a more permanent porosity (termed “microporous”) have gained attention due to their impressive combination of permeability (throughput) and permselectivity (separation efficiency) relative to the empirically defined “upper …
-
Post-Synthetic Chemical and Morphological Modifications of Polymer Membranes for Gas Separations
Microporous porous polymers have rigid backbone structures or bulky monomer units that inhibit efficient packing of polymer segments, resulting in high free volume materials with good diffusion selectivity when processed into films. As a result of these characteristics, microporous polymers became …
-
Vibrational spectroscopy studies of interdiffusion in polymer laminates and diffusion of water into polymer membranes.
… has been used to study the interdiffusion in polymer laminates at the interfacial region between the constituent polymer layers. The effects of the polymer molecular weight, annealing temperature, and annealing time have been studied. Three different laminates with various PMMA molecular …
-
Evaluation of polymer membranes for the gaseous separation of NOₓ and SO₂ from flue gas, An
Includes bibliographical references (pages 66-70).
-
Development of biomimetic, hybrid protein-synthetic membranes: determining protein insertion efficiency, membrane material suitability and relevance of aquaporin Z
Biomimetic membranes are designed to mimic the selective permeability of cell membranes, and can be engineered for a multitude of environmental applications including water purification, remediation, and sensing. Biomimetic membranes consist of membrane proteins, such as the bacterial water channel …
-
Polymer molecular sieve membranes
… thesis is focused on design and fabrication of membranes from novel molecularly defined polymers and understanding their physical properties, particularly the transport properties of gas molecules in polymer membranes. First, we demonstrate a simple approach of fabricating novel polymer …
-
Manufacture and Characterization of Ionic Polymer Transducers Employing Non-Precious Metal Electrodes
Ionic polymer membranes are commonly used in fuel cell power generation, water electrolysis and desalinization, chlorine generation, and other niche applications. Since the early 1990s ionic polymer membranes have also shown promise as distributed electromechanical actuators and sensors. The cost …
-
Synthesis and Chacterization of Novel Polybenzimidazoles and High-Solids Meta-Polybenzimidazoles
<p>Polymer electrolyte membrane (PEM) fuel cells are one of the most promising alternative power devices available due to their multiple applications as well as their clean and efficient operation. PEM fuel cells that operate at high temperatures (> 120oC) have advantages over low temperature PEM …
-
Nanoscale Liquid Dynamics in Membrane Matrices: Insights into Confinement, Molecular Interactions, and Hydration
… understanding of liquid dynamics confined in polymer membranes. Such knowledge guides the development of better polymer membranes for practical applications and contributes to the general understanding of confined liquid dynamics in various nanoporous materials. First, we investigate the …
-
Advanced characterization of transport and microstructural properties in membrane materials
Membranes are employed in a variety of sustainable water treatment and energy conversion technologies. Advancing membrane materials for new separations includes unraveling the complex structure-property relationships that govern water and salt transport in conjunction with scaling processing …
Page 1 of 2