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Characterization miniemulsions

Considering theoretically a copolymerization on the surface of a miniemulsion droplet, one should necessarily be aware of the fact that this process proceeds in the heterophase reaction system characterized by several spatial and time scales. Among the first ones are sizes of an individual block and macromolecules of the multiblock copolymer, the radius of a droplet of the miniemulsion and the reactor size. Taking into account the pronounced distinction in these scales, it is convenient examining the macrokinetics of interphase copolymerization to resort to the system approach, generally employed for the mathematical modeling of chemical reactions in heterophase systems [73]. [Pg.182]

Colloidal stability is usually controlled by the type and amount of the employed surfactant. In miniemulsions, the fusion-fission rate equilibrium during sonication and therefore the size of the droplets directly after primary equilibration depends on the amount of surfactant. For sodium dodecylsulfate (SDS) and styrene at 20% dispersed phase, it spans a range from 180 nm (0.3% SDS relative to styrene) down to 32 nm (50 rel.% SDS) (Fig. 4a). Again, it is anticipated that rapidly polymerized latexes also characterize the parental miniemulsion. As... [Pg.81]

Also in the inverse case, the droplet size throughout the miniemulsification process runs into an equilibrium state (steady-state miniemulsion) which is characterized by a dynamic rate equilibrium between fusion and fission of the... [Pg.86]

Due to the high water solubility of MAA, partitioning of the MAA in the water phase was expected. After polymerization, the obtained miniemulsions (latexes) and the colloidal nanoMIPs were characterized by gravimetric analysis, dynamic light scattering (DLS), gas adsorption measurements (BET), and transmission electron microscopy (TEM) as shown in Fig. 9. [Pg.136]

Besides the similarities between mini- and microemulsions, especially with respect to the nucleation process, microemulsions are characterized by very peculiar thermodynamics in this respect, there are many similarities between a macro- and a miniemulsion. Accordingly, we should focus on the reason why monomer dispersions are unstable in macroemulsions, while they are stable in miniemulsions. [Pg.161]

Our understanding of miniemulsion stability is limited by the practical difficulties encountered when attempting to measure and characterize a distribution of droplets. In fact, most of the well-known, established techniques used in the literature to characterize distributions of polymer particles in water are quite invasive and generally rely upon sample dilution (as in dynamic and static laser light scattering), and/or shear (as in capillary hydrodynamic fractionation), both of which are very likely to alter or destroy the sensitive equihbrium upon which a miniemulsion is based. Good results have been obtained by indirect techniques that do not need dilution, such as soap titration [125], SANS measurements[126] or turbidity and surface tension measurements [127]. Nevertheless, a substantial amount of experimental evidence has been collected, that has enabled us to estabhsh the effects of different amounts of surfactant and costabihzer, or different costabilizer structures, on stabihty. [Pg.170]

Crespy D, Landfester K (2005) Anionic polymerization of E-caprolactam in miniemulsion synthesis and characterization of polyamide-6 nanoparticles. Macromolecules 38 6882-6887 Weiss CK, Ziener U, Landfester K (2007) A route to nonfunctionalized and functionalized poly(n-butylcyanoacrylate) nanoparticles preparation in miniemulsion. Macromolecules 40 928-938... [Pg.41]

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... [Pg.44]

Erdem B, Sudol ED, Dimonie VL, et al. (2000) Encapsulation of inoiganic particles via miniemulsion polymerization. 111. Characterization of encapsulation. J Polym Sd Part A... [Pg.44]

Sun QH, Deng YL, Wang ZL (2004) Synthesis and characterization of polystyrene-encapsulated laponite composites via miniemulsion polymerization. Macromol Mater Eng 289 288-295... [Pg.46]

Liu XQ, Guan YP, Ma ZY, et al. (2004) Surface modification and characterization of magnetic polymer nanospheres prepared by miniemulsion polymerization. Langmuir 20 10278-10282... [Pg.46]

Lu SH, Forcada J (2006) Preparation and characterization of magnetic polymeric composite particles by miniemulsion polymerization. J Polym Sci Part A Polym Chem 44 4187-4203... [Pg.46]

Nunes JS, De Vasconcelos CL, Cabral FO, et til. (2(X)6) Synthesis tmd characterization of poly(ethyl methacrylate-co-methacrylic acid) magnetic particles via miniemulsion polymerization. Polymer 47 7646-7652... [Pg.47]

Zhang Y, Zhu SY, Yin LC, et al. (2008) Preparation, characterization and biocompatibility of poly(ethylene glycol)-poly(n-butyl cyanoacrylate) nanocapsules with oil core via miniemulsion polymerization. Fur Polym J 44 1654-1661... [Pg.48]

Erdem, B., E. D. Sudol, V. L. Dimonie, and M. S. El-Aasser, Encapsulation of inorganic particles via miniemulsion polymerization. II. Preparation and characterization of styrene miniemulsion droplets containing TiOj particles. J. Polym. Sci. A Polym. Chem. 38 (2000) 4431-4440. [Pg.327]

Zhang Y, Chen H, Shu X, Zou Q, Chen M (2009) Fabrication and characterization of raspberry-like PSt/Si02 composite microspheres via miniemulsion polymerization. Colloids Surf A Physicochem Eng Asp 350(l-3) 26-32... [Pg.51]

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... [Pg.235]

Taking all facts into account, the situation is characterized in such a way that the important question is to what extent it is possible to copy a miniemulsion by polymerization and not to realize a true 1 1 copy. [Pg.196]

R. J. Minari, M. Goikoetxea, L Beristain, M. PauUs, M. J. Barandiaran and J. M. Asua, Molecular characterization of alkyd/acrylic latexes prepared by miniemulsion polymerization, /App/ Polym Sci, 2009,114,3143-51. [Pg.124]

The miniemulsion polymerization products were washed with acetone to remove soluble components from the polymer composite. Spectroscopic characterization of the dried products was done using PA-FTIR spectroscopy. This method allows a convenient and fast spectroscopic analysis. [Pg.253]

No.24, 15th Dec.2000, p.4441-50 ENCAPSULATION OF INORGANIC PARTICLES VIA MINIEMULSION POLYMERIZATION. III. CHARACTERIZATION OF ENCAPSULATION... [Pg.66]

See other pages where Characterization miniemulsions is mentioned: [Pg.235]    [Pg.344]    [Pg.98]    [Pg.47]    [Pg.84]    [Pg.345]    [Pg.295]    [Pg.39]    [Pg.776]    [Pg.327]    [Pg.160]    [Pg.214]    [Pg.219]    [Pg.73]    [Pg.457]   
See also in sourсe #XX -- [ Pg.176 , Pg.177 , Pg.195 ]



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