화학공학소재연구정보센터
Journal of Colloid and Interface Science, Vol.340, No.1, 35-41, 2009
Fabrication of free-standing polyelectrolyte multilayer films: A method using polysulfobetaine-containing films as sacrificial layers
A new pH-dependent sacrificial system based on zwitterionic polysulfobetaine was proposed for the fabrication of free-standing polyelectrolyte multilayer films. The zwitterionic polysulfobetaine, poly(4-vinylpyridine propylsulfobetaine) (P4VPPS), was synthesized and its layer-by-layer (LbL) self-assembly behavior with poly(diallyldimethylammonium) (PDDA) as Counterpart was investigated by using UV-vis absorption spectroscopy, quartz crystal microbalance (QCM) and atomic force microscopy (AFM). The LbL multilayer films of PDDA/P4VPPS were successfully constructed in acid aqueous solution at pH 2 with 0.5 M NaCl. The resultant PDDA/P4VPPS multilayer films were pH-dependent and Could be disintegrated in alkali aqueous solutions, especially with pH >= 12. This disintegration property rendered such multilayer film as a sacrificial layer for further preparing free-standing polyelectrolyte multilayer films. The PDDA/poly(sodium 4-styrenesulfonate) (PSS) multilayer films deposited on the PDDA/P4VPPS sacrificial layer were confirmed to be successfully released after treated successively by alkali aqueous solution at pH 12 and ethanol. The obtained PDDA/PSS free-standing multilayer films had thicknesses of ca. 847 nm. (C) 2009 Elsevier Inc. All rights reserved.