Sodium dodecyl sulfate coated-polystyrene nanobeads for polymer composite membrane

Abstract

In this study, sodium dodecyl sulfate coated-polystyrene nanobeads were used as a carrier for CO2 separation membrane. Polystyrene nanobeads were prepared via emulsion polymerization and the surface potential of the particles remained unchanged, and the average value was −28 mV during the eight repeated measurements, indicating that the electrostatic dispersion stability of the SDS-PS NBs is very high. When sodium dodecyl sulfate coated-polystyrene nanobeads are incorporated into the polymeric composite membrane for CO2/N2 separation, these membranes surprisingly showed a selectivity of 252. In comparison with the neat PVP membrane, the separation performance was largely improved due to the interaction between polar CO2 molecules and polystyrene nanobeads to have −28 mV surface potential. FT-IR spectra shows the polystyrene nanobeads could weaken the carbonyl bond and caused the free volume to be abundant for N2 gas permeation. As a result, highly selective PVP/PS colloid composite membrane is successfully prepared for CO2 molecules, and the thermal stability was confirmed by TGA analysis.