Gas permeation properties of organosilicon-containing polystyrenes

摘要

para-Substituted polystyrenes that possess one to four Si atoms in each substituent were prepared using our original synthetic methods. The gas permeation properties of these polymer membranes were investigated in detail. With an increasing Si content in the polymer membrane, it was determined that the solubility of oxygen increased. The para-substituted polystyrenes with a branched substituent at the α-position showed higher permeability than those of the non-branched ones. With a higher glass transition temperature (T_g) of the membrane, a higher diffusion constant of oxygen was obtained. Consequently, poly [4-{bis(trimethylsilyl)methyl}styrene] which had the highest T_g among the membranes investigated in this study, showed the highest oxygen permeation coefficient (37-45 Barter). The activation energy of the oxygen permeation in this membrane was 3.0 kcal/mol.