Ion distribution in multilayers of weak polyelectrolytes: A neutron reflectometry study.

Neutron reflectometry was used to determine the distribution of salt ions and water in thin poly(acrylic acid) and poly(allylamine hydrochloride) polyelectrolyte multilayers assembled with and without salt. Increasing salt concentration reverses the exclusion of water from the substrate region, eventually leading to an asymmetric segregation of water near the substrate at high salt concentration. The counterions were found to localize near the substrate in films that were either assembled with salt or were exposed to salt solutions. In addition, the capping layer of the film was found to greatly influence the counterion distribution in the multilayer.

[1]  K. Yager,et al.  Water distribution in multilayers of weak polyelectrolytes. , 2006, Langmuir : the ACS journal of surfaces and colloids.

[2]  Hiroshi Ito,et al.  Direct measurement of the counterion distribution within swollen polyelectrolyte films. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[3]  K. Yager,et al.  Variable temperature, relative humidity (0%–100%), and liquid neutron reflectometry sample cell suitable for polymeric and biomimetic materials , 2005 .

[4]  Matthew D. Miller,et al.  Controlling the nanofiltration properties of multilayer polyelectrolyte membranes through variation of film composition. , 2004, Langmuir : the ACS journal of surfaces and colloids.

[5]  M. Serpe,et al.  Thermally modulated insulin release from microgel thin films. , 2004, Biomacromolecules.

[6]  Lei Zhai,et al.  pH-Gated Porosity Transitions of Polyelectrolyte Multilayers in Confined Geometries and Their Application as Tunable Bragg Reflectors , 2004 .

[7]  C. Barrett,et al.  Swelling Dynamics of Multilayer Films of Weak Polyelectrolytes , 2004 .

[8]  M. Rubner,et al.  Creating effective refractive index gradients within polyelectrolyte multilayer films: molecularly assembled rugate filters. , 2004, Langmuir : the ACS journal of surfaces and colloids.

[9]  Wanqin Jin,et al.  Use of Polyelectrolyte Layer-by-Layer Assemblies as Nanofiltration and Reverse Osmosis Membranes , 2003 .

[10]  C. Barrett,et al.  Acid-base equilibria of weak polyelectrolytes in multilayer thin films , 2003 .

[11]  A. Riegler,et al.  Polyelectrolytes. 2. Intrinsic or extrinsic charge compensation? Quantitative charge analysis of PAH/PSS multilayers , 2002 .

[12]  Michael F. Rubner,et al.  Methods of Loading and Releasing Low Molecular Weight Cationic Molecules in Weak Polyelectrolyte Multilayer Films , 2002 .

[13]  J. Schlenoff,et al.  Swelling and Smoothing of Polyelectrolyte Multilayers by Salt , 2001 .

[14]  F. Caruso,et al.  Nanoporous thin films formed by salt-induced structural changes in multilayers of poly(acrylic acid) and poly(allylamine). , 2001 .

[15]  M. Bruening,et al.  Controlling the Permeability of Multilayered Polyelectrolyte Films through Derivatization, Cross-Linking, and Hydrolysis , 2001 .

[16]  Andreas Voigt,et al.  pH-controlled macromolecule encapsulation in and release from polyelectrolyte multilayer nanocapsules. , 2001 .

[17]  Soo‐Hyoung Lee,et al.  Thin Film Optical Sensors Employing Polyelectrolyte Assembly , 2000 .

[18]  Michael F. Rubner,et al.  pH-Dependent Thickness Behavior of Sequentially Adsorbed Layers of Weak Polyelectrolytes , 2000 .

[19]  Michael F. Rubner,et al.  Controlling Bilayer Composition and Surface Wettability of Sequentially Adsorbed Multilayers of Weak Polyelectrolytes , 1998 .

[20]  Gero Decher,et al.  Fuzzy Nanoassemblies: Toward Layered Polymeric Multicomposites , 1997 .

[21]  J. Schlenoff,et al.  Multilayer Assemblies of Redox Polyelectrolytes , 1997 .

[22]  Johannes Schmitt,et al.  Internal structure of layer-by-layer adsorbed polyelectrolyte films : a neutron and X-ray reflectivity study , 1993 .

[23]  L. G. Parratt.  Surface Studies of Solids by Total Reflection of X-Rays , 1954 .