Abstract:

SiO₂ nanoparticles was mixed with anionic surfactant sodium dodecyl sulfate （SDS）, cationic surfactant cetyltrimethylammonium bromide （CTAB） and nonionic surfactant dodecyl alcohol polyoxyethylene （3） ether （AEO-3）, respectively, to prepare the aqueous foams thereof. The variations of foaming volume, half-life and microstructure were determined to reveal the influence of SiO₂ nanoparticles on the stability of aqueous foams. The results showed that when the mass fraction of the surfactant is constant, the foam stability gradually increase with the increase of the mass fraction of nanoparticles. When the mass fractions of the nanoparticles are 0.3%, the foaming volumes reached maxima with gas contents of 78.9%, 78.4% and 78.8%, respectively. Compared with the single systems of SDS, CTAB and AEO-3 at surfactant concentrations of 0.3%, 0.3% and 15%, respectively, these experimentally prepared foams did not affect the foaming volumes but the foam stability had been variously improved （the half-lives are 9.0 min, 8.2 min and 360 min, which are increase by 20%, 28.1% and 71.4%, respectively）.

Key words: foam, surfactant, SiO₂ nanoparticle, stability