title: Preparation of amorphous aluminum oxide-hydroxide nanoparticles in amphiphilic silicone-based copolymer microemulsions.
abstract: Organo-inorgano nanocomposites with colloidal dimensions have interesting optical, catalytic, and mechanical properties, particularly when such hybrids are reinforced with transition metal oxide nanoparticles. Nanoparticles with a mean size of 1.0-2.4 nm are obtained through hydrolysis of aluminum isopropoxide in the L(2) phase of amphiphilic (PDMS-POE) polydimethylsiloxane-polyoxyethylene Silwet L-7607-octanol/acetylacetone-water mixtures. The particle sizes are related weakly to the microemulsion composition: 0.8-1.2 nm for 20 wt% Silwet L-7607 and 2.0-2.4 nm for 50 wt% Silwet L-7607. Protection of the particles against aggregation is ensured through their confinement in the intraaggregate colloidal domains. Factors affecting the hydrolysis-condensation process of acetylacetone-complexed aluminum isopropoxide in copolymer-poor and copolymer-rich regions of PDMS-POE W/O microemulsions are studied by Fourier transform infrared spectroscopy, small angle X-ray scattering, and transmission electron microscopy. Prepared nanoparticulate dispersions possess long-term stability and form clear mixtures in different organic polar and nonpolar solvents.
authors.affiliation: Casali Institute of Applied Chemistry, The Hebrew University of Jerusalem, Jerusalem, 91904, Israel.
authors.forename: Yana
authors.initials: Y
authors.lastname: Berkovich
authors.forename: Abraham
authors.initials: A
authors.lastname: Aserin
authors.forename: Ellen
authors.initials: E
authors.lastname: Wachtel
authors.forename: Nissim
authors.initials: N
authors.lastname: Garti