Preparation and Separation Properties of Cyclodextrin-Segmented PU Membranes
Polyurethane (PU) pervaporation (PV) membranes are promising for the recovery of aromatic compounds in water. The novel cyclodextrin-segmented PU membranes were prepared using polybutadiene (HTPB) as soft segment and 4, 4’-diaminodiphenyl methane (MDA) and β-cyclodextrins (β-CDs) as chain extenders. The membranes had the special structures with β-CDs chemically segmented in PU backbones. The structures of these membranes were characterized by means of FT-IR and the swelling characteristics of those were studied. Furthermore, the PV performances were investigated for separating phenol/water mixtures at different temperatures. The results showed that the β-CDs-segmented PU membrane had better permeability and selectivity than those with β-CDs physically mixed. For 0.50 wt% phenol in feed mixture at 60 °C, these membranes had a flux of 4.05 kg µm m-2 h-1 and separation factor of 25. The permeation fluxes increased with the increased feed temperature, while the separation factors decreased.
H. Ye et al., "Preparation and Separation Properties of Cyclodextrin-Segmented PU Membranes", Advanced Materials Research, Vol. 304, pp. 219-223, 2011