Distribution of Surfactants near Acrylic Latex Film Surfaces:  A Comparison of Conventional and Reactive Surfactants (Surfmers)

Abstract

The use of reactive surfactants is a promising way of avoiding the deleterious effects on film properties caused by the segregation of conventional surfactants. In this work, the distributions of conventional and reactive anionic surfactants in acrylic latex films are compared. Atomic force microscopy was used to examine the surface of the films cast from high solids content acrylic latexes, and Rutherford backscattering spectrometry provided depth profiles of the surfactants. It was proven conclusively that the use of surfmers is an effective way of eliminating unwanted surfactant exudation. The amount of conventional surfactant (sodium lauryl sulfate (SLS)) exuded to the surface increased with the temperature at which the films were annealed (60, 90, and 125 °C), but the migration of the surfmer (sodium tetradecyl maleate) was very minimal and only weakly dependent on temperature. An unexpectedly large amount of conventional surfactant was exuded to the film surface when annealed at 125 °C. This result suggests that its transport to the surface might be facilitated by the enhanced mobility of poly(acrylic acid) shells at temperatures above the polymer's glass transition temperature (ca. 106 °C).

Correlation of Silicone Incorporation into Hybrid Acrylic Coatings with the Resulting Hydrophobic and Thermal Properties

“…The film was peeled, rinsed with water to eliminate any surfactant migrated to the surfaces, 23 and the contact angle of both interfaces, air-film and film-substrate, was measured. Moreover, almost no differences between air-film and film-substrate interfaces were observed, most likely because the homogeneous distribution of the PDMS through the film, which is in accordance with the MR observation.…”

Skin Development during the Film Formation of Waterborne Acrylic Pressure-Sensitive Adhesives Containing Tackifying Resin

“…RBS was used to search for surfactant near the surface, by the method described elsewhere. [33,48] S and K are both found in the surfactants used in the latex synthesis. According to our RBS analysis, there was an excess of S and K at the acrylic latex surface.…”

Drying rate variations of latex dispersions due to salt induced skin formation

“…Despite this, many published studies on latex film formation concern surfactant free systems, with dispersions cleaned from surfactants and low molecular species like salt, etc. Even though the role of surfactants in the film formation process often has been neglected, there are some phenomenological studies on films made from dispersions having conventional surfactants [7,14,15] and polymerizable surfactants [16][17][18] but there are no reports on the effect of the presence of salt in dispersions on film formation. Initiators used in the emulsion polymerization process are often inorganic salts, which will reduce the electrostatic repulsion between the particles [19,20].…”