Specific Anion Effects on the Growth of a Polyelectrolyte Multilayer in Single and Mixed Electrolyte Solutions Investigated with Quartz Crystal Microbalance

Abstract

The specific anion effects on the deposition of a multilayer formed by poly(sodium 4-styrene sulfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDDA) have been investigated by use of quartz crystal microbalance with dissipation (QCM-D) in single and mixed electrolyte solutions. In the case of single electrolyte solutions, the frequency change (-Deltaf) demonstrates that the multilayer in NaBr, NaClO(3), and NaCl solutions grows in a nonlinear mode, which is dominated by the penetration of PSS. In NaF, CH(3)COONa, NaH(2)PO(4), and Na(2)SO(4) solutions, the multilayer growth mainly determined by the conformation of PDDA chains exhibits a linear mode. The growth shows a mode in between in NaHCO(3) solution. The dissipation change (DeltaD) has slight dependence on anion species except in the cases of Br(-), HCO(3)(-), and SO(4)(2-). DeltaD remarkably increases with layer number in NaHCO(3) solution, indicating the formation of a relatively loose multilayer. In a mixed electrolyte solution containing chaotropic and kosmotropic anions, the multilayer growth is dominated by the chaotropic anions due to the anion competition effects. The effects of anions on the deposition of multilayer are nonadditive.

Divalent–Anion Salt Effects in Polyelectrolyte Multilayer Depositions

“…34−37 For a univalent anion, the properties of PEMLs correlate well with that anion's position in the Hofmeister series, 38 as measured by the ion's polarizability, hydration entropy, or Jones-Dole viscosity B parameter. 23,34−36,39−41 The Hofmeister ordering of anions, for example, correlates with their effects on the thickness, 17,23,28,34,41,42 degree of swelling, 40 and extent of layer interpenetration 36 for PEMLs formed by common polyelectrolytes: sodium polystyrene sulfonate (PSS) and polyallylamine hydrochloride (PAH) or polydiallyldimethylammonium chloride (PDDA). The Hofmeister ordering of cations similarly explains the salt dependence of PSS/PDDA 17,23,41 and PSS/PAH 20,23,35 film properties, though the effect of cations is muted by their smaller polarizability differences.…”

Formation and Degradation of Layer-by-Layer-Assembled Polyelectrolyte Polyrotaxane Capsules

“…This is a similar trend to that observed by Liu et al for the assembly of poly(diallyldimethylammonium)/poly(4-styrene sulfonate) (PDDA/PSS) multilayers. 39 The ƒ (848 Hz) and D (63) for the assembly of eight layers of PE PRXs in the presence of SO4 2both increase, as compared to the Clsystem at the same concentration or ionic strength of 0.3 M NaCl (-612 Hz) ( Figure S4). It is, however, unclear whether the contribution of water is significant in the total mass adsorbed since we were unable to ob- gated; this number includes dimeric capsules as well and is less than the extent of aggregation that was present in the previously prepared batches of capsules.…”

Refining classical force fields for ionic liquids: theory and application to [MMIM][Cl]

“…Many published FFs for charged molecules like polyelectrolytes or ILs are based on reduced net charges and, thus, already include e el in an empirical manner, [41][42][43][44][45] in order to solve the problem of slow dynamics. A reduced net-charge has also been observed for ion pairs 21,46 and clusters 45,[47][48][49] ] were derived also from the crystalline phase using the ESP method and from a small bulk system with CAB. 51 A comparison of the charges shows that for the [BMIM] system, both methods agree quite well, while significant differences arise between the crystalline and the liquid state for the [EMIM] system.…”