Dynamic surface elasticity of polyelectrolyte/surfactant adsorption films at the air/water interface: Dodecyltrimethylammonium bromide and copolymer of sodium 2-acrylamido-2-methyl-1-propansulfonate with N-isopropylacrylamide

Characterization limits of a polymer adsorbed under a monolayer by GIXD measurements

“…This has been observed in a range of different systems, which include poly-(styrene sulfonate) (PSSt)-dodecyltrimethylammonium bromide (C 12 TAB) [6][7][8], xanthan-C 12 TAB [9], poly(acrylic acid) -C 12 TAB [10], polydiallyldimethylammonium chloride-sodium dodecyl sulfate [11], and poly(2-acrylamido-2methyl-1-propansulfonate-co-isopropylacrylamide)-C 12 TAB [12]. However, most of these studies deal with soluble surfactant interacting with polymer.…”

“…However, most of these studies deal with soluble surfactant interacting with polymer. Moreover, different sensitive techniques, such as neutron [6][7][8]10] and X-ray reflectivity [9], ellipsometry [9], and dynamic surface elasticity [12], have allowed considerable progress in the comprehension of the adsorption phenomena at the interfaces.…”

Dynamic Surface Elasticity of Polyelectrolyte/Surfactant Adsorption Films at the Air/Water Interface: Carboxylmethylchitosan and Cetyltrimethylammonium Bromide

“…[29] For sodium 2-acrylamido-2-methyl-1-propansulfonate with N-isopropylacrylamide=dodecyltrimethyl ammonium bromide (AMPS-NIPAM=C 12 TAB) solutions, the non-monotonous kinetic dependency of the dynamic surface elasticity was attributed to the formation of a loose surface structure with some loops and tails protruding into the bulk phase, which is caused by the charge compensation of AMPS-NIPAM via interaction with C 12 TAB in the case that AMPS-NIPAM has low charge density and contains amphiphilic isopropylacrylamide monomers. [25] The transition from a rigid adsorption layer structure to a looser one due to the desorption of polymer=surfactant complexes from the surface layer in longer surface age is not necessary to explain the drop of surface elasticity in the present CMCH= C 16 TAB solutions because no macroscopic aggregates appear in the investigated concentration range and polyacids have high charge density and exhibit the properties of strong polyelectrolyte. Another interpretation was proposed in polyacrylic acid=alkyltrimethylammonium bromides (PAA=C n TAB) solutions, in which similar kinetic plots of surface elasticity were observed and significant deviations of the surface tension oscillation from a pure harmonic shape were discovered.…”

“…Qualitatively, similar concentration dependences of the dynamic surface elasticity on surfactant concentration were also obtained for other polyelectrolyte=surfactant solutions. [24][25][26] In the whole range of investigated surfactant concentration, the imaginary part of the dynamic surface elasticity is below 10 mN=m. It is much smaller than the real part of the dynamic surface elasticity and the adsorption layer is purely elastic.…”

“…Similar responses of elasticity on surface age were observed for some other polyelectrolyte=surfactant solutions and proposed different interpretations. [24][25][26][27][28][29] For polydiallyldimethylammonium chloride=sodium dodecyl sulfate (PVPmCl=SDS) solutions, the local maximum in the kinetic dependency of the dynamic surface elasticity appeared in the concentration range of heterogeneous bulk solutions and was connected with the desorption of polymer=surfactant complexes from the surface as a result of the formation of macroscopic aggregates in the bulk solution. [29] For sodium 2-acrylamido-2-methyl-1-propansulfonate with N-isopropylacrylamide=dodecyltrimethyl ammonium bromide (AMPS-NIPAM=C 12 TAB) solutions, the non-monotonous kinetic dependency of the dynamic surface elasticity was attributed to the formation of a loose surface structure with some loops and tails protruding into the bulk phase, which is caused by the charge compensation of AMPS-NIPAM via interaction with C 12 TAB in the case that AMPS-NIPAM has low charge density and contains amphiphilic isopropylacrylamide monomers.…”