The Max-Planck-Society is gratefully acknowledged for financial support. S.Z. thanks the Alexander on Humboldt Foundation for a research fellowship. We are also indebted to Dr. Igor Djerdj for recording the HRTEM images and Dr. Minhua Cao and Jinming Wu for carrying out the XRD tests.

The dispersion behavior of crystalline zirconia nanoparticles with a diameter of 3.8nm, synthesized from zirconium-(IV) isopropoxide and benzyl alcohol in tetrahydrofurane (THF), methyl methacrylate (MMA), and styrene (St), was investigated using 3-(trimethoxysilyl)propyl methacrylate (MPS), ethyl 3,4-dihydroxycinnamate (EDHC), allylmalonic acid (AMA), and trimethylolpropane mono allyl ether (TMPMA) as ligating stabilizers containing polymerizable vinyl groups. Analytical ultracentrifugation (AUC) and transmission electron microscopy (TEM) analyses prove that the as-synthesized wet zirconia nanoparticles can be dispersed inTHFwithout any agglomeration when using the appropriate ligand concentrations. Surface-adsorbed water, if intentionally introduced during the washing step, and also air humidity seriously deteriorate their dispersibility. These results suggest that the excellent dispersibility of the zirconia nanoparticles is a direct consequence of the nonaqueous synthesis approach. Fourier transform infrared spectra (FTIR) and thermogravimetric analysis (TGA) illustrate that MPS, EDHC, and AMA are chemically attached but TMPMA is physically attached to the surface of the zirconia nanoparticles. Transparent dispersions of zirconia nanoparticles can also be prepared in MMA with the help of MPS, EHDC, and AMA or in St with MPS and TMPMA, opening a promising pathway for the direct application of zirconia nanoparticles in polymer-based nanocomposites.

Europium(III) (Eu3þ)-doped polyurethane films were prepared by mixing Eu-methacrylic acid complex (Eu(MA)3) with aliphatic polyurethane oligomer and subsequently curing under UV irradiation. Transmission electron microscopy photos and the appearance of the resulting hybrid films showed that phase separation occurred only at an Eu(MA)3 content above 20 wt.-%. Fluorescence spectra indicated that the fluorescence of Eu3þ was barely influenced by the polyurethane matrix and its intensity increased with an Eu(MA)3 content in the range of approximately 0 to 10 wt.-%. An obvious applied external-field-dependent magnetization (M) of polyurethane/Eu(MA)3 films, namely, an increasingMat low field and a decreasingMat high field, was observed at room temperature from the hysteresis loops, which was influenced by both the Eu(MA)3 content and the ultrasonication imposed on the coatings before curing. It seems that ultrasonication leads to a thermodynamically-unstable structure of Eu3þ in hybrid films, which can be fixed by UV curing but gradually rearranges to its original form during the thermal-curing process, and enhances the diamagnetic part of the hybrid film. Thus, the magnetic property of Eu3þ-doped polyurethane film at room temperature can be adjusted by simply changing the preparation method and the Eu(MA)3 content instead of the type of Eu3þ-organic complex.

UV-curable polymer/nanosized indium-doped tin oxide (ITO) nanocomposite coatings were fabricated by blending ITO slurry and oligomer and reactive monomers. The preparation of ITO slurry and the effect of the ITO content on the electrical conductivity, hardness and optical properties of the nanocomposite coats were investigated. It was found that the electric conductivity and UV absorbance of the nanocomposite coats increased while the hardness and refractive index first increased then decreased with increasing ITO concentration since too high ITO resulted in the incomplete curing of the coatings.

Polystyrene-graft-poly(ethylene glycol) copolymers (PS-g-PEG) were successfully synthesized using the "grafting-through" method. The graft copolymers and the surface properties of their coats were characterized by 1H-NMR, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), static contact angle measurement, and atomic force microscopy (AFM). Both DSC and TEM indicated that the graft copolymers had a microphase separated structure. AFM showed the microphase separated structure also occurred at the coat surface, especially at high PEG content, which could also be indirectly confirmed by the XPS and contact angle results. The formation mechanism of the microphase separated structure was discussed. 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1458-1465, 2007