Amphiphilic Pickering Emulsifiers Based on Mushroom-Type Janus Particles.

Amphiphilic Pickering Emulsifiers Based on Mushroom-Type Janus Particles.

Langmuir : the ACS journal of surfaces and colloids (2015-07-15)

E Passas-Lagos, F Schüth

ABSTRACT

Iron-based mushroom-type Janus particles consisting of a poly(sytrene-co-divinylbenzene) and a silica moiety both with controllable morphologies were successfully synthesized on the gram scale and investigated as surfactants for Pickering emulsions. Two oil-water model systems, namely toluene-water and vegetable oil-water, were stabilized, giving mainly water-in-oil (w/o) emulsions. By varying several parameters, including Janus particle morphologies and the oil-water ratio, fine-tuning of the emulsion systems was possible; it was even possible to invert the continuous phase to an oil-in-water (o/w) system. Furthermore, the emulsions were stable against coalescence and sedimentation and could be easily separated by centrifugation or a strong magnet. The synthesized mushroom-type Janus particles are suitable for creating Pickering emulsions and can be used as building blocks for creating nanostructures with tailored properties for specific applications.

MATERIALS

Product Number

Brand

Product Description

83697

Sigma-Aldrich

Rhodamine 6G, suitable for fluorescence, BioReagent

414565

Sigma-Aldrich

Divinylbenzene, technical grade, 80%

W292907

Sigma-Aldrich

Isopropyl alcohol, ≥99.7%, FCC, FG

169099

Sigma-Aldrich

Divinylbenzene, technical grade, 55%

151238

Sigma-Aldrich

Glycidyl methacrylate, 97%, contains 100 ppm monomethyl ether hydroquinone as inhibitor

252433

Sigma-Aldrich

Rhodamine 6G, Dye content 99 %

62840

Sigma-Aldrich

L-Lysine, crystallized, ≥98.0% (NT)

779342

Sigma-Aldrich

Glycidyl methacrylate, ≥97.0% (GC)

R4127

Sigma-Aldrich

Rhodamine 6G, Dye content ~95 %

S4972

Sigma-Aldrich

Styrene, ReagentPlus^®, contains 4-tert-butylcatechol as stabilizer, ≥99%

L5501

Sigma-Aldrich

L-Lysine, ≥98% (TLC)

700320

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 5 nm avg. part. size, 5 mg/mL in toluene

700304

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 20 nm avg. part. size, 5 mg/mL in toluene

700312

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size, 5 mg/mL in toluene

278475

Sigma-Aldrich

2-Propanol, anhydrous, 99.5%

725331

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 5 nm avg. part. size, 5 mg/mL in H₂O

725366

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 20 nm avg. part. size, 5 mg/mL in H₂O

725358

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size, 5 mg/mL in H₂O

518158

Sigma-Aldrich

Iron(II,III) oxide, 99.99% trace metals basis

59304

Sigma-Aldrich

2-Propanol, BioUltra, for molecular biology, ≥99.5% (GC)

437522

Sigma-Aldrich

2-Propanol, ACS reagent, ≥99.5%

310069

Sigma-Aldrich

Iron(II,III) oxide, powder, <5 μm, 95%

244511

Sigma-Aldrich

Toluene, anhydrous, 99.8%

A7460

Sigma-Aldrich

Ammonium persulfate, BioXtra, ≥98.0%

637106

Sigma-Aldrich

Iron(II,III) oxide, nanopowder, 50-100 nm particle size (SEM), 97% trace metals basis

733458

Sigma-Aldrich

2-Propanol, electronic grade, 99.999% trace metals basis

A3678

Sigma-Aldrich

Ammonium persulfate, for molecular biology, suitable for electrophoresis, ≥98%

I9516

Sigma-Aldrich

2-Propanol, for molecular biology, BioReagent, ≥99.5%

747343

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 5 nm avg. part. size (TEM), amine functionalized, 1 mg/mL Fe in H₂O, dispersion

747319

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size (TEM), PEG functionalized, 1 mg/mL Fe in H₂O, dispersion