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Polymeric Shell (polymeric + shell)
Selected AbstractsPolymer-Mediated Dispersion of Gold Nanoparticles: Using Supramolecular Moieties on the PeripheryADVANCED MATERIALS, Issue 38-39 2009Adam D. Celiz A novel method of dispersing gold nanoparticles (Au NPs) is described. Thiol-terminated ureido-pyrimidinone (UPy)-functionalized polymers are attached to Au NPs to create a polymeric shell with quadruple hydrogen-bonding units on the periphery. By increasing the amount of UPy loading on the Au NPs, self-assembly into aggregates is observed with both 1H NMR spectroscopy and transmission electron microscopy. [source] Highly magnetic latexes from submicrometer oil in water ferrofluid emulsionsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 8 2006Franck Montagne Abstract The synthesis of functionalized submicrometer magnetic latex particles is described as obtained from a preformed magnetic emulsion composed of organic ferrofluid droplets dispersed in water. Composite (polystyrene/,-Fe2O3) particles were prepared according to a two-step procedure including the swelling of ferrofluid droplets with styrene and a crosslinking agent (divinyl benzene) followed by seeded emulsion polymerization with either an oil-soluble [2,2,-azobis(2-isobutyronitrile)] or water-soluble (potassium persulfate) initiator. Depending on the polymerization conditions, various particle morphologies were obtained, ranging from asymmetric structures, for which the polymer phase was separated from the inorganic magnetic phase, to regular core,shell morphologies showing a homogeneous encapsulation of the magnetic pigment by a crosslinked polymeric shell. The magnetic latexes were extensively characterized to determine their colloidal and magnetic properties. The desired core,shell structure was efficiently achieved with a given styrene/divinyl benzene ratio, potassium persulfate as the initiator, and an amphiphilic functional copolymer as the ferrofluid droplet stabilizer. Under these conditions, ferrofluid droplets were successfully turned into superparamagnetic polystyrene latex particles, about 200 nm in size, containing a large amount of iron oxide (60 wt %) and bearing carboxylic surface charges. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2642,2656, 2006 [source] From polymeric particles to multifunctional nanocapsules for biomedical applications using the miniemulsion processJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 3 2010Katharina Landfester Abstract The miniemulsions process represents a versatile tool for the formation of polymeric nanoparticles consisting of different kinds of polymer as obtained by a variety of polymerization types ranging from radical, anionic, cationic, enzymatic polymerization to polyaddition, and polycondensation. The process perfectly allows the encapsulation of hydrophilic and hydrophobic liquids and solids in polymeric shells, molecularly dissolved dyes or other components. In combination with a specific functionalization of the nanoparticles' or nanocapsules' surfaces and the possibility to release substances in a defined way from the interior, complex nanoparticles or nanocapsules are obtained, which are ideally suited for application in biomedical application as marker and targeted drug-delivery system. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 493,515, 2010 [source] Synthesis of polymeric core,shell particles using surface-initiated living free-radical polymerizationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2007Sarav B. Jhaveri Abstract An easy and novel approach to the synthesis of functionalized nanostructured polymeric particles is reported. The surfactant-free emulsion polymerization of methyl methacrylate in the presence of the crosslinking reagent 2-ethyl-2-(hydroxy methyl)-1,3-propanediol trimethacrylate was used to in situ crosslink colloid micelles to produce stable, crosslinked polymeric particles (diameter size , 100,300 nm). A functionalized methacrylate monomer, 2-methacryloxyethyl-2,-bromoisobutyrate, containing a dormant atom transfer radical polymerization (ATRP) living free-radical initiator, which is termed an inimer (initiator/monomer), was added to the solution during the polymerization to functionalize the surface of the particles with ATRP initiator groups. The surface-initiated ATRP of different monomers was then carried out to produce core,shell-type polymeric nanostructures. This versatile technique can be easily employed for the design of a wide variety of polymeric shells surrounding a crosslinked core while keeping good control over the sizes of the nanostructures. The particles were characterized with scanning electron microscopy, transmission electron microscopy, optical microscopy, dynamic light scattering, and Raman spectroscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1575,1584, 2007 [source] | ||||||||||