Evaluation of Supercritical Fluid Interactions with Polymeric Materials

Samuel P, Saw an, Yeong-Tarng Shieh, Jan-Hon Su, Gurusamy Manivannan and W, Dale Spall 

Supercritical carbon dioxide has a critical temperature of 31°C and a critical pressure of 1070 psi. Carbon dioxide as a cleaning solvent has a number of advantages these include low human toxicity, no waste solvent, low cost, ready availability, complete recovery of extracted agents and extracted substances, environmental acceptability, complete and ready recycling, etc. 

In this chapter, we present results of the testing of a broad spectrum of polymers in carbon dioxide over a range of temperatures and pressures and evaluation of the effect of the high pressure carbon dioxide on the chemical/physical properties of materials tested. The testing was performed in a static manner with four controlled variables, namely temperature, pressure, treatment time and decompression time. The evaluation of the interaction of high pressure carbon dioxide with polymers included sorption and swelling behavior, solubility issue, plasticization and crystallization, and mechanical properties. The results of these evaluations are discussed in three sections Sorption, Swelling and Dissolution of Carbon Dioxide in Polymers at Elevated Pressure, Thermal Properties, and Mechanical Properties.  

0 SORPTION, SWELLING AND DISSOLUTION OF CARBON DIOXIDE IN POLYMERS AT ELEVATED PRESSURE 

Supercritical carbon dioxide has recently begun to be studied as a substitute for chlorofluorocarbons (CFCs) as a cleaning solvent for industrial processes. Common materials of construction in industry encompasses all of the familiar materials including ceramic, glasses, metals, polymers, adhesives, etc. Of these materials, it is anticipated 

Supercritical fluid technology has been widely employed for extraction and purification processes in foods and pharmaceuticals industry I I and for techniques such as supercritical fluid chromatography. Recently there has be i intwest in applying the use of 

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Evaluation of Supercritical Fluid Interactions with Polymeric Materials... 

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