Butyl Acrylate → Styrene 4-styrenesulfonic Acid Sodium Salt

Participants

Reaction Conditions

Reaction Steps

In a 250 mL Morton flask (fitted with mechanical stirrer, thermometer, and oil bath heating) under argon atmosphere were combined 4-styrenesulfonic acid sodium salt hydrate (0.20 g), butyl acrylate (Aldrich, 20.0 g), a-olefin sulfonate surfactant (Rhodia, Rhodacal A-246/L, 25.0 g of a ca. 40% aqueous solution), and water (145 g). The mixture was stirred and heated in a 90° C. oil bath until an internal temperature of ca. 75° C. was obtained, and then a solution of initiator (K2S2O8, Aldrich, 0.40 g, dissolved in 10 mL H2O) was added all at once via a syringe. The appearance of the nearly opaque aqueous monomer emulsion changed quickly over less than 5 minutes to form a translucent, bluish scattering emulsion. The mixture was stirred and heated for an additional 6 h in the 95° C. oil bath (internal temperature ca. 92° C.) to decompose the excess initiator. The mixture was cooled with stirring, and filtered to remove a small amount of suspended solid. Yield 198.9 g of emulsion, pH ca. 4 to pH paper, 15.65% solids, particle size=12.3 nm Rh, by DLS, (2nd cumulant analysis PDI=0.07).

Provenance & Evidence