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

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

252433

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Rhodamine 6G, Dye content 99 %

62840

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L-Lysine, crystallized, ≥98.0% (NT)

779342

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Glycidyl methacrylate, ≥97.0% (GC)

R4127

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Rhodamine 6G, Dye content ~95 %

S4972

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

L5501

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L-Lysine, ≥98% (TLC)

700320

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

700304

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

700312

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

278475

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2-Propanol, anhydrous, 99.5%

725331

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

725366

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

725358

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

518158

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

59304

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

09913

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Ammonium persulfate, BioUltra, for molecular biology, ≥98.0% (RT)

310069

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

A7460

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Ammonium persulfate, BioXtra, ≥98.0%

675431

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2-Propanol, HPLC Plus, for HPLC, GC, and residue analysis, 99.9%, poly coated bottles

637106

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

733458

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

A3678

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

I9516

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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