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

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

Poly(methyl methacrylate)/zirconia (PMMA/ZrO2) nanocomposites with ZrO2 content as high as 15 wt% were prepared by modifying non-aqueous synthesized ZrO2 nanoparticles with methacryloxypropyltrimethoxysilane (MPS) in tetrahydrofuran, dispersing MPS-functionalized ZrO2 nanoparticles in MMA and following in situ bulk polymerization with controlled pre-polymerization time. The MPS-functionalized ZrO2 nanoparticles showed an efficient crosslinking role in the polymerization, leading to a complete gel of PMMA at 5 wt% of ZrO2 content. Homogeneous dispersion of the ZrO2 nanoparticles at primary particle size level was observed in all nanocomposites, which results in good clarity of the obtained nanocomposites. Hardness tests (pendulum hardness tests and indentation tests) and antiscratch tests (abrasion tests and nano scratch tests) were employed to probe the surface mechanical properties of the nanocomposites. The properties of nanocomposites as a function of ZrO2 content, revealing from various characterization techniques, are not consistent and discussed in detail. At low ZrO2 content, the mechanical properties are enhanced by the formed crosslinking structure. However, remarkable improvements of hardness and scratch resistance of PMMA were achieved when 15 wt% of ZrO2 content was embedded.

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.

Waterborne adhesives are extremely environment-friendly but unfortunately deficient in mechanical properties. In this article, nanosilica, stemming from tetraethyl orthosilicate (TEOS), silica sol, and/or fumed silica powder, was employed to reinforce the waterborne silylated polyether adhesives. Effects of TEOS content, silica sol content, and the type and content of fumed silica on the shear strength of the adhesive were investigated using a scanning electronic microscope and an electronic instron tester and the strengthening mechanisms of different silica source were discussed. All the shear strengths of silylated polyether adhesives first increased and then decreased as TEOS content, silica sol content or fumed silica content increased. Colloidal silica particles was less efficient than fumed silica particles for reinforcing the polyether adhesive but can increase the shear strength of hydrophobic fumed silica embedded adhesive. Comparing the adhesives with the hydrophilic fumed silica (HS-5) or the extremely hydrophobic fumed silica (TS-720), the adhesive with moderate hydrophobic fumed silica (TS-610) had the highest shear strength. The maximal shear strength of 2.5 MPa was achieved when TEOS, silica sol, and fumed silica were combined. It seemed that TEOS, silica sol, and fumed silica played crosslinking (with polyether chain), dispersing (for fumed silica), and reinforcing roles on waterborne adhesive, respectively. This reinforcing mechanism opened a new way to fabricate waterborne adhesives (or coatings) with high performances.