Membranes of crosslinked hyperbranch polymers and their pervaporation properties

To explore the novel pervaporation materials, the membranes of hyperbranched polyglycidol (HPG) and hyperbranched poly (amine-ester) (HPAE) were prepared by crosslinking terminal hydroxyl groups with 4,4’-oxydiphthalic anhydride (ODPA) and glutaraldehyde (GA), respectively. Scanning electron microscope (SEM) revealed that the crosslinked HPG-ODPA and HPAE-GA membranes had the dense and homogenous matrices. The intrinsic hydrophilicity of the membranes makes them having water permeation preference in pervaporation process. On the basis of their swelling behavior, the pervaporation properties of these two crosslinked membranes in separating water from water/isopropanol mixture were discussed and compared.

Using 4,4’-oxydiphthalic anhydride (ODPA) and glutaraldehyde (GA) as crosslinking reagent, the hydroxyl-terminated HPG and HPAE were prepared into crosslinked membranes with homogeneous matrix. With excellent hydrophilicity and higher swelling degree in water, these two crosslinked membranes of HPG-ODPA and HPAE-GA performed the water permeation preference. In pervaporation dehydration of water/isopropanol mixtures with water in 10 wt%, the permeation flux and separation factor for HPG-ODPA membrane was 260 g/m2Áh and 116 while the corresponding ‘‘973’’ Program (Grant No. 2003.CB615705), ‘‘863’’ Program (Granted No. 2006AA03Z233) and China postdoctoral science foundation (No. 20060400338) are gratefully acknowledged for supporting the related researches.