Poly(methyl methyacrylate)-block-polydimethylsiloxane (PMMA-b-PDMS) copolymers with various compositions were synthesized with PDMS-containing macroazoinitiator (MAI), which was first prepared by a facile onestep method in our lab. Results from the characterizations of X-ray photoelectron spectroscopy (XPS), contact angle measurements, and atomic force microscopy (AFM) showed that the copolymer films took on a gradient of composition and more PDMS segments enriched at the film surfaces, which then resulted in the low surface free energy and little microphase separation at the film surfaces. By contrast, transmission electron microscopy (TEM) analysis demonstrated that distinct microphase separation occurred in bulk. Slight crosslinking of the block copolymers led to much steady morphology and more distinct microphase separation, in particularly for copolymers with low content of PDMS. 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104:3356-3366, 2007

WO3·H2O nanotubes are successfully synthesized with the aid of intercalated polyaniline (PANI) under relatively mild conditions. More interestingly, the WO3·H2O nanotubes have a rectangular cross-section structure formed through a rolling mechanism. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared analysis, UV-vis-near-IR spectroscopy, selected-area electron diffraction, and vibrating-sample magnetometry analysis are employed to characterize the morphology, structure, and properties of the nanotubes.

Tungsten (W)-doped vanadium dioxide (VO2) particles were successfully synthesized by hydrolysis of vanadyl sulfate mingled with a small amount of sodium tungstate dihydrate and subsequent calcination. XPS analyses demonstrated that the vanadium oxide was composed of stoichiometric VO2, and the doped W content in VO2 particles could be easily controlled by the concentration of W precursor. XRD patterns indicated that all the W-doped VO2 particles were monoclinic crystals, and the W dopant almost had no influence on the crystal structure of VO2 particles. DSC analyses displayed that the critical phase transition temperature of VO2 particles could be reduced to room temperature or even lower by increasing the dopedWfraction. UV-vis-NIR spectra showed that the W-doped VO2 particles embedded acrylic coating had very good thermochromic performance. r 2007 Elsevier B.V. All rights reserved.

The colloidal silica particles were first modified with methyltriethoxylsilane and methacryloxypropyltrimethoxysilane, respectively, then embedded into acrylic based polyurethane using blending method or in situ method. The effects of the silane couple agent type, modified silica content and preparation method on the redispersibility of silica particles and mechanical properties of polyurethane coats were investigated using 29Si NMR, TGA, FT-IR, particle size analyzer, SEM, DMA and Instron machine. It was found that different silane couple agent and preparation method had obvious influences on the redispersibility and mechanical properties. © 2006 Elsevier B.V. All rights reserved.

The de-agglomeration and dispersion of nano-TiO2 powder is little reported, although nano-TiO2 powder has been widely used due to its unique optical properties. In this study, an agitator bead mill (MiniZETA 03E, Netzsch) accompanied with an ultrasonicator was employed to de-agglomerate the nano-TiO2 powder in butyl acetate, and the effects of ultrasonic pretreatment, dispersant dosage, agitation speed, solid content of TiO2 suspension, and bead diameter were systemically investigated. It is found that ultrasonic pretreatment leads to short grinding time to reach the limiting fineness, low specific energy input, and small limiting mean size. All other technical parameters have also some influence on the limiting fineness and grinding time. However, the former strongly depends on agitation speed while the latter on both agitation speed and dispersant dosage. A solvent-borne nano-TiO2 suspension with limiting mean size of 110 nm can be successfully result under the optimal technical conditions and showed excellent UV-shielding property and transparence when it was incorporated into polyester/melamine coatings.