Miniemulsion polymerization morphology

Zhang JJ, Gao G, Zhang M, et al. (2006) ZnO/PS core-shell hybrid microspheres prepared with miniemulsion polymerization. J Colloid Interface Sci 301 78-84 Mahdavian A, Stirrafi Y, Shabankareh M (2009) Nanocomposite particles with core-shell morphology. 111. Preparation and characterization of nano Al203-poly(styrene-methyl methacrylate) ptirticles via miniemulsion polymerization. Polym Bull 63 329-340... 

Ge X, Wang M, Yuan Q, et al. (2009) The morphological control of anisotropic polystyrene/sflica hybrid particles prepared by radiation miniemulsion polymerization. Chem Commun 2765—2767... 

Mirzataheri M, Mahdavian A, Atai M (2009) Nanocomposite particles with core-shell morphology IV an efficient approach to the encapsulation of Cloisite 30B by poly (styrene-co-butyl acrylate) and preparation of its nanocomposite latex via miniemulsion polymerization. Colloid Polym Sd 287 725-732... 

Mahdavian AR, Sehri Y, Salehi-Mobarakeh H (2008) Nanocomposite particles with core-sheU morphology. 11. An investigation into the affecting parameters on preparation of Fc3 04-poly (butyl acrylate-styrene) particles via miniemulsion polymerization. Eur Polym J 44 2482-2488... 

Combination of both water-soluble and oil-soluble initiators has also been used in miniemulsion polymerization. Choi et al. ° successfully used both water-soluble potassium persulfate and oil-soluble 2,2 -azobis-(2-methyl butyronitrile) initiators in the miniemulsion polymerization of styrene. Ghazaly et al." used both water-soluble and oil-soluble initiators in the copolymerization of -butyl methacrylate with cross-linking monomers. Variations in the particle morphologies were found between the water-soluble and oil-soluble initiators, depending on the hydrophobicity of the cross-linking monomer. 

Mahdaviein AR, Ashjari M, Mobarakeh HS (2008) Ntinocomposite ptirticles with core-sheU morphology. 1. PiepEuation and characterization of Fe304-poly(butyl acrylate-styrene) particles via miniemulsion polymerization. J Appl Polym Sci 110 1242-1249... 

Sun Y, Wang B, Wang HP et al (2007) Controllable preparation of magnetic polymer microspheres with different morphologies by miniemulsion polymerization. J Colloid Interface Sci 308 332-336... 

The effect of the amount of surfactant SDS, hydrophobe hexadecane, iron oxide magnetic particles, MAA and non-ionic cellulose ether, hydroxyethylcellulose, on the magnetic latex morphology, surface quality and size distribution was studied by Forcada et al. for the encapsulation of magnetic particles by miniemulsion polymerization of St. Optimal conditions were 2-3% of SDS, 9-12% of hexadecane, 10% of iron oxide and 2% of HEC, relative to the total amount of St and iron oxide [177]. 

Tiarks et al. have described in detail the theory of droplets composed of binary mixtures in relation to the preparation of polymeric nanocapsules containing HD by miniemulsion polymerization using poly(methyl methacrylate) (PMMA) or PS polymer [37]. First, a miniemulsion of oil phase (monomer -r HD -t initiator) dispersed in aqueous phase and containing an appropriate surfactant is prepared by ultrasonication. The polymerization is initiated by heating the emulsion to 68 °C. When the polymer is formed it separates from the HD phase and, depending on the interfadal tension and spreading coeffidents of monomer/polymer, HD (hydrophobe) and water, capsules with different morphologies are obtained. 

Different sized nanocapsules are formed by a miniemulsion polymerization of variety of monomers in the presence of larger amounts of hydrophobe [117]. Hydrophobe and monomer form a common miniemulsion before polymerization, whereas the polymer is immiscible with the hydrophobe and phase-separates throughout the polymerization to form particles with a morphology consisting of a hollow polymer structure surrounding the hydrophobe. Differences in the hydrophilicity of oil and polymer turned out to be the driving force for the formation of nanocapsules. In the case of poly(methyl methaciylate) (PMMA) and hexadecane (HD), the pronounced differences in hydrophilicity are suitable for direct nanocapsule formation. In the case of styrene as the monomer, the hydrophilicity of the polymer phase has to be adjusted in order to favor the nanocapsule structure, which is done either by the addition of an appropriate comonomer or initiator. 

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