Polystyrene-silica core-shell composite particles are prepared by one-step emulsion polymerization with a nonionic initiator VA-086, solely stabilized by silica nanoparticles. The silica nanoparticles are successfully incorporated as the shell, likely due to the fact that the nanoparticles are thermodynamically favorable to adsorb and remain at the liquid-liquid interfaces during the emulsion p...

A facile strategy was developed here to prepare cross-linked polymeric nanocapsules (CP nanocapsules) with silica nanoparticles as templates. The silica nanoparticle@cross-linked polymer nanoparticles were prepared by the encapsulation of the silica nanoparticles by the one-pot approach via surface-initiated atom transfer radical polymerization of hydroxyethyl acrylate in the presence of N,N'-m...

Monolithic silica columns and their use in high peak-capacity HPLC separations are reviewed. Monolithic silica columns can potentially provide higher overall performance than particle-packed columns based on the variable external porosity and variable through-pore size/skeleton size ratios. The high permeability of monolithic silica columns resulting from the high porosity is shown to be advant...

Preliminary Studies of the Influence of Forces and Kinetics on Interfacial Colloidal Assembly. (August 2004) Gregory Fernandes, B.E., Mumbai University Chair of Advisory Committee: Dr.Michael Bevan In this research we illustrate how particle-particle and particle-substrate interactions affect structure in interfacial colloidal systems. A number of tools are used to quantify characteristics of d...

A novel high surface area heterogeneous catalyst based on solution phase colloidal nanoparticle chemistry has been developed. Monodisperse platinum nanoparticles of 1.7-7.1 nm have been synthesized by alcohol reduction methods and incorporated into mesoporous SBA-15 silica during hydrothermal synthesis. Characterization of the Pt/SBA-15 catalysts suggests that Pt particles are located within th...

Core-polystyrene/shell-silica nanocomposite particles are synthesized by simple soap-free emulsion polymerization employing positively charged silica sol. The polymerization is initiated with conventional anionic KPS. It is found that the silica sol should be added after the initiation and nucleation of the soap-free emulsion polymerization in order to obtain colloidally stable composite partic...

several samples of mesoporous silica were prepared via sol-gel chemistry in the presence of ctab as template with variation of stirring intensity and aging time, ratios of ctab/sio2 and nh4oh/h2o in synthesis mixture. effects of aging temperature, hydrothermal treatment and ter-butanol addition to the synthesis mixture on the textural properties of obtained samples were also studied. results of...

Although there have been a long history of studying and using immobilized enzymes, little has been reported regarding the nature of immobilized cofactors. Herein we report that cofactor NAD(H) covalently attached to silica nanoparticles successfully coordinated with particle-immobilized enzymes and enabled multistep biotransformations. Specifically, silica nanoparticle-attached glutamate dehydr...

The introduction of sulfonic acid modified silica in Nafion nanocomposite membranes is a good method of improving the Nafion performance at high temperature and low relative humidity. Sulfonic acid-modified silica is bifunctional, with silica phase expected to offer an improvement in membranes hydration while sulfonic groups enhance proton conductivity. However, as discussed in this paper, this...

the removal of as(iii) ions from aqueous solutions has been investigated using silica ceramic under different experimental conditions of initial arsenite concentration, adsorbent dose, temperature and ph. better removal was obtained at temperature 25âºc and ph 7.5. the adsorption data have been explained in terms of langmuir and freundlich equations. the sorption kinetics was tested for the pse...