C_nTAB/polystyrene sulfonate mixtures at air–water interfaces: effects of alkyl chain length on surface activity and charging state

Abstract

The physical behavior of surfactant/polyelectrolyte mixtures in bulk and at interfaces is studied with respect to the surfactant chain length.

Helping Strands: Polyelectrolyte Assists in Surfactant Assembly below Critical Micelle Concentration

“…All freshly prepared samples (Figure 3a−c, blue) also exhibit a phenyl peak at 3060 ± 6 cm −1 from adsorbed and oriented PSS. 9,24,35 At 0.20 mM C 12 TAB/PSS (Figure 3a), there is little change between fresh (blue) and aged (red) spectra, indicating minimal time dependence at this concentration. However, both 4.0 and 6.5 mM C 12 TAB/PSS (Figure 3b,c) show a very large decrease in the phenyl signal for aged samples (red) compared to fresh samples (blue), consistent with a significant depletion of adsorbed PSS.…”

“…35 It matches the behavior of the C 12 TAB/PSS system at the air/water interface. 21,24,26,32,36,37 The grey box indicates the 2ΦR in which P/S complexes slowly precipitate, leaving behind a clear supernatant partially depleted of both PSS and C 12 TAB. The surface pressure of aged samples (red squares) below the 2ΦR does not significantly deviate from those of fresh samples (blue line), which indicates full equilibration at those concentrations.…”

“…One of the most puzzling features of this system is its decreasing surface synergy with increasing surfactant chain length. 24,25 While the C 14 TAB/PSS and C 16 TAB/PSS systems exhibit low overall adsorption, the shorter-chain C 10 TAB/PSS and C 12 TAB/PSS systems are noteworthy for their enhanced coadsorption, 25,26 and the latter system is the focus of this study due to its noteworthy surface activity. 19,20,23,27−33 Relevant to these studies, Campbell et al identify a decrease in air/water surface pressure of C 12 TAB/ PSS within the 2ΦR when samples are set aside for one month to allow the precipitate to settle.…”

Polymer–Colloid Complexes Based on Cationic Imidazolium Amphiphile, Polyacrylic Acid and DNA Decamer

“…This is mainly due to the possibility of the control of the properties of these systems by the variation of the chemical structure, ratio and concentration of components, molecular weight of the polymer, pH of the medium, temperature and ionic strength [7][8][9]. In addition, the fabrication of complexes can be mediated by different mechanisms, including the hydrophobic effect, van der Waals interactions and hydrogen bonding, with the contribution of dominating electrostatic interactions [10][11][12][13]. For these reasons, mixtures of polyelectrolytes and oppositely charged surfactants are characterized by the complicated behavior of solutions [14][15][16].…”

Surfactant‐mediated formation of alginate layers at the water‐air interface

“…[34][35][36][37][38][39][40][41][42][43][44] Nevertheless, the use of biopolymers makes the study of polymer-surfactant interactions more complicated because of a broader variation of the polymer chains (molecular weight, monomer sequence, branching, etc). However, there are some important studies, [45][46][47][48] for example, the interesting hyaluronate-cationic surfactant complexes, which are investigated by Thalberg and Lindman, 49 or the carboxymethylcellulose-cationic surfactant complexes investigated by Langevin et al 50 Other important examples are the chitosan-anionic carboxylate surfactants studied by Chiappisi and Gradzielski 51 ; a good overview of the neglected class of surfactants with multiresponsive properties is given in Chiappisi. 52 Because of this complexity, studies about polysaccharide-surfactant interactions are less often, and most of them focused on the bulk properties.…”