posted on 2021-05-18, 18:11authored byBashayer
S. Aldakkan, Mohamed A. Hammami, Genggeng Qi, Mazen Y. Kanj, Emmanuel P. Giannelis
A stimuli-responsive,
sub-100 nm nanoparticle (NP) platform with
a hydrolyzable ester side chain for in situ generation of surfactants
is demonstrated. The NPs were synthesized via copolymerization of
vinyl-laurate and vinyl-acetate [p-(VL-co-VA), 3:1 molar ratio] and stabilized with a protective poly(ethylene-glycol)
shell. The NPs are ∼55 nm in diameter with a zeta potential
of −54 mV. Hydrolysis kinetics in an accelerated, base-catalyzed
reaction show release of about 11 and 30% of the available surfactant
at 25 and 80 °C, respectively. The corresponding values in seawater
are 22 and 76%. The efficiency of the released surfactant in reducing
the interfacial tension, altering wettability, and stabilizing oil–water
emulsion was investigated through contact angle measurements and laser
confocal scanning microscopy and benchmarked to sodium laurate, a
commercially available surfactant. All these measurements demonstrate
both the efficacy of the NP system for surfactant delivery and the
ability of the released surfactant to alter wettability and stabilize
an oil–water emulsion.