Solvay Emulsifier Boosts Coatings, Adhesives Performance

Reactsurf 2490 from Solvay is an APE-free polymerizable surfactant designed as a primary emulsifier for acrylic, vinyl-acrylic and styrene-acrylic latex systems. Reactsurf 2490 is designed to improve emulsion performance to deliver superior functional and aesthetic benefits in exterior coatings and pressure-sensitive adhesives (PSAs), compared to conventional surfactants, even at high temperatures.

In addition to exterior coatings and pressure-sensitive adhesives, other common uses of Reactsurf 2490 include paint binders, adhesives and sealants, textile and nonwoven binders, paper coatings, and building and construction applications.

“Exterior coatings and pressure-sensitive adhesives are both prone to surfactant leaching,” says Janice Ng, Coatings Asia Pacific business development manager. “In exterior coatings exposed to harsh environmental conditions, leaching leads to dirt pick-up and water marks, while it leads to water whitening in PSAs. Reactsurf 2490 prevents surfactant migration, which improves water whitening resistance for PSAs and dirt pickup resistance for exterior coatings. This means clear label products retain their original appearance, and exterior surfaces remain clean and dirt free.”

Reactsurf 2490 is highly reactive and easily incorporated during the emulsion polymerization reaction. The company says it minimizes the need for secondary emulsifiers, thereby facilitating fast and simple design of latexes. REACH-certified and water-soluble, Reactsurf 2490 also promotes compliance with regulatory requirements for APE-free solutions. Its combination of properties includes low dynamic surface tension and critical micelle concentration, good particle size control, low grit and low foaming, in turn enabling better film hardness and antiblocking.

In tests of elastomeric coating binders, the company reports Reactsurf 2490 delivered improved blocking resistance and superior dirt pickup resistance after three months of outdoor exposure. Additionally, initial tests demonstrated improved water whitening resistance in PSA applications.