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Surface deposition and phase behavior of oppositely charged polyion-surfactant ion complexes. Delivery of silicone oil emulsions to hydrophobic and hydrophilic surfaces.

Clauzel M, Johnson ES, Nylander T, Panandiker RK, Sivik MR, Piculell L - ACS Appl Mater Interfaces (2011)

Bottom Line: The effect on the deposition of dilution of the bulk solution in contact with the surface was also investigated by gradual replacement of the bulk solution with 1 mM aqueous NaCl.The largest amount of deposited material after dilution was found for hydrophilic silica and for the least-hydrophobic cationic polymers.For the least-hydrophobic polyions, no significant codeposition of silicone oil was detected at hydrophobized silica after dilution if the initial SDS concentration was high.

View Article: PubMed Central - PubMed

Affiliation: Physical Chemistry, Kemicentrum, Lund University, Box 124, SE-221 00, Lund, Sweden. maryline.clauzel@gmail.com

ABSTRACT
The adsorption from mixed polyelectrolyte-surfactant solutions at hydrophobized silica surfaces was investigated by in situ -ellipsometry, and compared to similar measurements for hydrophilic silica surfaces. Three synthetic cationic copolymers of varying hydrophobicity and one cationic hydroxyethyl cellulose were compared in mixtures with the anionic surfactant sodium dodecylsulfate (SDS) in the absence or presence of a dilute silicone oil emulsion. The adsorption behavior was mapped while stepwise increasing the concentration of SDS to a polyelectrolyte solution of constant concentration. The effect on the deposition of dilution of the bulk solution in contact with the surface was also investigated by gradual replacement of the bulk solution with 1 mM aqueous NaCl. An adsorbed layer remained after complete exchange of the polyelectrolyte/surfactant solution for aqueous NaCl. In most cases, there was a codeposition of silicone oil droplets, if such droplets were present in the formulation before dilution. The overall features of the deposition were similar at hydrophobic and hydrophilic surfaces, but there were also notable differences. SDS molecules adsorbed selectively at the hydrophobized silica surface, but not at the hydrophilic silica, which influenced the coadsorption of the cationic polymers. The largest amount of deposited material after dilution was found for hydrophilic silica and for the least-hydrophobic cationic polymers. For the least-hydrophobic polyions, no significant codeposition of silicone oil was detected at hydrophobized silica after dilution if the initial SDS concentration was high.

No MeSH data available.


Related in: MedlinePlus

Summary of adsorbed amounts from mixed polyelectrolyte/SDS solutions before dilution (see text) for (a) HPA/DMAM, (b) HEA/MAPTAC, (c) AA/MAPTAC, and (d) catHEC. Conditions were 100 ppm polyelectrolyte, 400 ppm emulsion (when present), SDS as indicated. Empty symbols = without emulsion, filled symbols = with emulsion. Hydrophobic surfaces are indicated by red color and square symbols, and hydrophobized surfaces by blue color and circles. Lines (guides to the eye) connect average values for formulations with (solid) or w/o (dashed) emulsion.
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fig7: Summary of adsorbed amounts from mixed polyelectrolyte/SDS solutions before dilution (see text) for (a) HPA/DMAM, (b) HEA/MAPTAC, (c) AA/MAPTAC, and (d) catHEC. Conditions were 100 ppm polyelectrolyte, 400 ppm emulsion (when present), SDS as indicated. Empty symbols = without emulsion, filled symbols = with emulsion. Hydrophobic surfaces are indicated by red color and square symbols, and hydrophobized surfaces by blue color and circles. Lines (guides to the eye) connect average values for formulations with (solid) or w/o (dashed) emulsion.

Mentions: The effect on deposition when diluting the formulation (data corresponding to those shown in Figure 4) are shown in detail for all investigated mixtures in the Supporting Information. To obtain an overview of the quantitative variations and trends in these experiments, we have summarized data on adsorbed amounts immediately before diluting the bulk solution and at steady state after dilution in Figures 7 and 8, respectively. Each panel shows results for one polyion, at two or more initial surfactant concentrations, comparing hydrophilic and hydrophobic surfaces with and without added emulsion droplets. The observed considerable variation in adsorbed amount is interesting from the point of view of applications, and it must ultimately reflect the molecular interactions responsible for deposition. We will now walk through this multidimensional parameter set by considering one parameter at a time.


Surface deposition and phase behavior of oppositely charged polyion-surfactant ion complexes. Delivery of silicone oil emulsions to hydrophobic and hydrophilic surfaces.

Clauzel M, Johnson ES, Nylander T, Panandiker RK, Sivik MR, Piculell L - ACS Appl Mater Interfaces (2011)

Summary of adsorbed amounts from mixed polyelectrolyte/SDS solutions before dilution (see text) for (a) HPA/DMAM, (b) HEA/MAPTAC, (c) AA/MAPTAC, and (d) catHEC. Conditions were 100 ppm polyelectrolyte, 400 ppm emulsion (when present), SDS as indicated. Empty symbols = without emulsion, filled symbols = with emulsion. Hydrophobic surfaces are indicated by red color and square symbols, and hydrophobized surfaces by blue color and circles. Lines (guides to the eye) connect average values for formulations with (solid) or w/o (dashed) emulsion.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211372&req=5

fig7: Summary of adsorbed amounts from mixed polyelectrolyte/SDS solutions before dilution (see text) for (a) HPA/DMAM, (b) HEA/MAPTAC, (c) AA/MAPTAC, and (d) catHEC. Conditions were 100 ppm polyelectrolyte, 400 ppm emulsion (when present), SDS as indicated. Empty symbols = without emulsion, filled symbols = with emulsion. Hydrophobic surfaces are indicated by red color and square symbols, and hydrophobized surfaces by blue color and circles. Lines (guides to the eye) connect average values for formulations with (solid) or w/o (dashed) emulsion.
Mentions: The effect on deposition when diluting the formulation (data corresponding to those shown in Figure 4) are shown in detail for all investigated mixtures in the Supporting Information. To obtain an overview of the quantitative variations and trends in these experiments, we have summarized data on adsorbed amounts immediately before diluting the bulk solution and at steady state after dilution in Figures 7 and 8, respectively. Each panel shows results for one polyion, at two or more initial surfactant concentrations, comparing hydrophilic and hydrophobic surfaces with and without added emulsion droplets. The observed considerable variation in adsorbed amount is interesting from the point of view of applications, and it must ultimately reflect the molecular interactions responsible for deposition. We will now walk through this multidimensional parameter set by considering one parameter at a time.

Bottom Line: The effect on the deposition of dilution of the bulk solution in contact with the surface was also investigated by gradual replacement of the bulk solution with 1 mM aqueous NaCl.The largest amount of deposited material after dilution was found for hydrophilic silica and for the least-hydrophobic cationic polymers.For the least-hydrophobic polyions, no significant codeposition of silicone oil was detected at hydrophobized silica after dilution if the initial SDS concentration was high.

View Article: PubMed Central - PubMed

Affiliation: Physical Chemistry, Kemicentrum, Lund University, Box 124, SE-221 00, Lund, Sweden. maryline.clauzel@gmail.com

ABSTRACT
The adsorption from mixed polyelectrolyte-surfactant solutions at hydrophobized silica surfaces was investigated by in situ -ellipsometry, and compared to similar measurements for hydrophilic silica surfaces. Three synthetic cationic copolymers of varying hydrophobicity and one cationic hydroxyethyl cellulose were compared in mixtures with the anionic surfactant sodium dodecylsulfate (SDS) in the absence or presence of a dilute silicone oil emulsion. The adsorption behavior was mapped while stepwise increasing the concentration of SDS to a polyelectrolyte solution of constant concentration. The effect on the deposition of dilution of the bulk solution in contact with the surface was also investigated by gradual replacement of the bulk solution with 1 mM aqueous NaCl. An adsorbed layer remained after complete exchange of the polyelectrolyte/surfactant solution for aqueous NaCl. In most cases, there was a codeposition of silicone oil droplets, if such droplets were present in the formulation before dilution. The overall features of the deposition were similar at hydrophobic and hydrophilic surfaces, but there were also notable differences. SDS molecules adsorbed selectively at the hydrophobized silica surface, but not at the hydrophilic silica, which influenced the coadsorption of the cationic polymers. The largest amount of deposited material after dilution was found for hydrophilic silica and for the least-hydrophobic cationic polymers. For the least-hydrophobic polyions, no significant codeposition of silicone oil was detected at hydrophobized silica after dilution if the initial SDS concentration was high.

No MeSH data available.


Related in: MedlinePlus