Abstract
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.
Original language | English |
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Article number | 084901 |
Journal | Journal of Chemical Physics |
Volume | 129 |
Issue number | 8 |
DOIs | |
State | Published - 2008 |
Externally published | Yes |
Funding
The authors would like to thank the Canadian Neutron Beam Centre, NRC Chalk River Laboratories for beam time. Funding was provided by the McGill FQRNT Centre for Self-Assembled Chemical Structures and NSERC Canada.