Miniemulsion polymerization templates: A systematic comparison between low energy emulsification (Near-PIT) and ultrasound emulsification methods

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 374; no. 1-3; pp. 134 - 141
• Main Authors: Galindo-Alvarez, Johanna, Boyd, David, Marchal, Philippe, Tribet, Christophe, Perrin, Patrick, Marie-Bégué, Emmanuelle, Durand, Alain, Sadtler, Véronique
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 20.01.2011; Elsevier
• Subjects: agitation; Chemical and Process Engineering; Chemistry; coatings; Colloidal state and disperse state; emulsifying; emulsions; Emulsions. Microemulsions. Foams; energy; Engineering Sciences; Exact sciences and technology; General and physical chemistry; heat; Low-energy emulsification method; Miniemulsion polymerization; Nanoemulsion; Nanoparticles; phase transition; Physical and chemical studies. Granulometry. Electrokinetic phenomena; polymerization; polystyrenes; surfactants; temperature; Transitional phase inversion; ultrasonics; Nanoparticles; Miniemulsion polymerization; Transitional phase inversion; Low-energy emulsification method; Nanoemulsion; Agitation; Emulsification; Nanoparticle; Polymerization; Suspension; Surfactant; Free radical; Solid; Template; Ethylene oxide polymer; Emulsion; Energy; Heating; Formulation; Preparation; Styrene polymer; Monomer; Ultrasound; Diameter; PHASE INVERSION TEMPERATURE; AFFINITY INVERSION; STABILITY; EMULSION INVERSION; OIL-WATER SYSTEMS; NANOCAPSULES; NONIONIC SURFACTANTS; NANO-EMULSIONS; NANOPARTICLES; DROP SIZE
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2010.11.019

[Display omitted] ▶ A low-energy emulsification method has been designed and showed to allow the preparation of polymeric particles smaller than usual miniemulsification methods (about 75nm). ▶ The performances of Near-PIT procedure were comparable to ultrasound emulsification. ▶ Contrary to usual PIT methods, the Near-PIT procedure did not imply heating the samples at temperatures higher than PIT. Poly(ethylene oxide)-covered polystyrene nanoparticles were prepared by free radical miniemulsion polymerization after using an original low energy emulsification procedure called Near-PIT method. This procedure consisted in heating the initial monomer emulsion up to a temperature close to the phase inversion temperature (PIT) but lower. The surfactants used were commercial Brij® 78 and Brij® 700 and mixtures of both. The Near-PIT method was showed to allow the preparation of nanoparticle suspensions with average diameters lower than 100nm and solid contents higher than 20wt% while avoiding heating the initial monomer emulsion above PIT like in usual low energy methods. The influences of various formulation and operating parameters were investigated. Finally, the Near-PIT method was compared to other well-known procedures for nanoparticle preparation, miniemulsion polymerization after ultrasound emulsification and macroemulsion polymerization under mechanical agitation. The performances of Near-PIT procedure were comparable to ultrasound emulsification.