(543c) Free Volume And Transport Properties In Polymeric Materials

Poly(dimethylsiloxane) (PDMS), a rubbery polymer, has the potential to be used in the natural gas separation due to its high gas permeability and high vapor/gas selectivity. Cavity size (free volume) distributions of PDMS are calculated at different temperatures using an energetic based cavity-sizing algorithm. Free volume of PDMS decreases with increasing temperatures. We also simulate solubility of CO2 in PDMS at different temperatures. Solubility decreases as the temperature increases. Good agreement is obtained between simulation and experimental results. Key word: Solubility, free volume, CO2.