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

28-5435

Sigma-Aldrich

Styrene, SAJ first grade, ≥99.0%

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)

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

747254

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 10 nm avg. part. size (TEM), carboxylic acid functionalized, 5 mg/mL Fe in H₂O, dispersion

790508

Sigma-Aldrich

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

747327

Sigma-Aldrich

Iron oxide(II,III), magnetic nanoparticles solution, 30 nm avg. part. size (TEM), amine functionalized, 1 mg/mL Fe in H₂O, dispersion

30-3280

Sigma-Aldrich

Toluene, JIS special grade, ≥99.5%

15-2360

Sigma-Aldrich

2-Propanol, suitable for HPLC

01-4920

Sigma-Aldrich

Ammonium persulfate, SAJ first grade, ≥95.0%

30-3290

Sigma-Aldrich

Toluene, SAJ first grade, ≥99.0%

15-2320

Sigma-Aldrich

2-Propanol, JIS special grade, ≥99.5%

30-3302

Sigma-Aldrich

Toluene, JIS 300, for residue analysis, ≥99.8%

30-3304

Sigma-Aldrich

Toluene, JIS 1000, for residue analysis, ≥99.8%

700320

Sigma-Aldrich

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

733458

Sigma-Aldrich

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

15-2330

Sigma-Aldrich

2-Propanol, SAJ first grade, ≥99.0%

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

725331

Sigma-Aldrich

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