Hybrid polymer particles

El-Aasser M S, Li M, Jeong P, Daniels E S, Dimonie V L and Sudol E D (2001) Nano-hybrid polymer particles via thee mini emulsion process DECHEMA... 

Most examples discussed so far made use of amorphous inorganic supports or sol-gel processed hybrid polymers. Highly disperse materials have recently become accessible via standard processes and, as a result, materials with various controlled particle size, pore diameter are now available. Micelle-templated synthesis of inorganic materials leads to mesoporous materials such as MCM-41, MCM-48, MSU, and these have been extensively used as solid supports for catalysis [52]. Modifications of the polarity of the material can increase the reactivity of the embedded centre, or can decrease its susceptibility to deactivation. In rare cases, enhanced stereo- or even... 

A hybrid method, particle-based SCFT (SCMF) [67], was formulated as an alternative to mean-field SCFT and was applied to complex phenomena such as solvent evaporation in thin polymer films and reconstruction of chemically patterned substrates. 

TEM and ultracentrifuge results showed (see Fig. 16) that this process results in effective encapsulation of the carbon with practically complete yield only rather small hybrid particles, but no free carbon or empty polymer particles, were found. It has to be stated that the hybrid particles with high carbon contents do not possess spherical shape, but adopt the typical fractal structure of carbon clusters, coated with a thin but homogeneous polymer film. The thickness of the monomer film depends on the amount of monomer, and the exchange of monomer between different surface layers is - as in miniemulsion polymerization - suppressed by the presence of an ultrahydrophobe. 

I j Preparation of Monodisperse Ultrafine Hybrid Silica Particles by Polymer Modification... 

Bon and Kumacheva and coworkers [104] demonstrated that monodisperse solids-stabilized droplets could be generated in a microfluidic flow focusing device, whereby the solid particles were initially present in the dispersed phase. Polymerization of the monomer droplets led to hybrid polymer microspheres. They also showed that non-spherical particles could be obtained by geometric confinement of the droplets in the channel [104,105]. 

Muller and coworkers prepared disc-like polymer Janus particles from assembled films of the triblock copolymer SBM and, after hydrolysis of the ester groups into methacrylic acid units, used these as Pickering stabilizer in the soap-free emulsion polymerization of styrene and butyl acrylate [111]. Armes and coworkers described the synthesis of PMMA/siUca nanocomposite particles in aqueous alcoholic media using silica nanoparticles as stabilizer [112], extending this method to operate in water with a glycerol-modified silica sol [113, 114]. Sacanna showed that methacryloxypropyltrimethoxysilane [115] in the presence of nanosized silica led to spontaneous emulsification in water, which upon a two-step polymerization procedure afforded armored particles with an outer shell of PMMA [116]. Bon and coworkers demonstrated the preparation of armored hybrid polymer latex particles via emulsion polymerization of methyl methacrylate and ethyl methacrylate stabilized by unmodified silica nanoparticles (Ludox TM O) [117]. Performance of an additional conventional seeded emulsion polymerization step provided a straightforward route to more complex multilayered nanocomposite polymer colloids (see Fig. 14). 

Metal/polymer hybrid particles displaying an eccentric structure were very recently reported [327, 328]. The key parameter for the formation of such morphologies was the addition of the metal nanoparticles after the polymerization was started. The reaction was performed in a water/ethanol mixture (40/60 by weight), ethanol playing a key role in the reduction of charge effects. Each hybrid particle contained only one metal nanoparticle anchored on the poly(styrene-co-DVB-ct)-NaSS) polymer particle. The strategy proved to be successful for gold, palladium, and platinum. 

Charleux B, D Agosto F, Delaittre G (2010) Preparation of hybrid latex particles and coreshell particles through the use of controlled radical polymerization techniques in aqueous media. Adv Polym Sd doi 10.1007/12 2010 64... 

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