Cost effective poly(urethane-imide)-POSS membranes for environmental and energy-related processes

The control of anthropogenic carbon dioxide (CO₂) emissions is one of the most challenging environmental issues facing industrialized countries because of its implications to atmospheric CO₂ levels and climatic change. Burning of fossil fuels is responsible for the majority of these CO₂ emissions and, therefore, there is significant interest in developing technologies that will reduce CO₂ emissions. The membrane-based separation processes are not only cost effective and environmentally friendly, but also with many novel polymeric materials available, offer much more versatility and simplicity in customized system designs. The ability to selectively pass one component in a mixture while rejecting others describes the perfect separation device. We have synthesized a set of poly(urethane-imide)-POSS (PUI) by the simple condensation reaction of isocyanate terminated polyurethane (PU) prepolymer and anhydride terminated polyimide (PI) prepolymer. The PUIs were characterized by TGA, SEM, and AFM analyses. Thermal stability of the PU was found to increase by the introduction of imide component. Gas permeation measurements were studied for O₂, N₂, and CO₂ gases by employing different pressures using constant volume/variable pressure apparatus.