title: Responsive polyelectrolyte multilayers assembled at high ionic strength with an unusual collapse at low ionic strength.
abstract: Responsive polyelectrolyte multilayers (PEMs) of poly(diallyl dimethyl ammonium chloride) (PDADMAC) and poly(styrene sodium sulfonate) (PSS) with thicknesses between 350 and 400 nm for 11 deposited polyelectrolyte layers were fabricated assembling the polyelectrolytes at 3 M NaCl. When the 3 M NaCl bulk solution is replaced by water, the PEMs release water, approximately a 46% of the total mass, and experience a thickness reduction of more than 200 nm. Changes in thickness and water content are fully reversible. The film recovers its original thickness and water content when it is exposed again to a 3 M NaCl solution. A responsive polymer film is achieved with the capability of swelling at high ionic strength and collapsing in water with variations in thickness of hundred of nanometers.
authors.affiliation: CIC biomaGUNE, Paseo Miramón 182 C, 20009 San Sebastián, Spain.
authors.forename: Joseba
authors.initials: J
authors.lastname: Irigoyen
authors.forename: Lulu
authors.initials: L
authors.lastname: Han
authors.forename: Irantzu
authors.initials: I
authors.lastname: Llarena
authors.forename: Zhenwei
authors.initials: Z
authors.lastname: Mao
authors.forename: Changyou
authors.initials: C
authors.lastname: Gao
authors.forename: Sergio E
authors.initials: SE
authors.lastname: Moya
mesh_terms: D004573:Electrolytes / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D009994:Osmolar Concentration; D011095:Polyethylenes / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D004573:Electrolytes; D011095:Polyethylenes; D011137:Polystyrenes; D000644:Quaternary Ammonium Compounds; D014867:Water; C041004:poly-N,N-dimethyl-N,N-diallylammonium chloride; D012965:Sodium Chloride; C003321:polystyrene sulfonic acid