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Wuhan, China

Huang Y.,Wuhan University | Zeng M.,Wuhan University | Zeng M.,University of Sichuan | Ren J.,Wuhan University | And 4 more authors.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2012

A series of novel graphene oxide (GO)/poly(acrylic acid- co-acrylamide) super-absorbent hydrogel nanocomposites were prepared by in situ radical solution polymerization. The effects of GO content on the chemical structure, morphology and miscibility of the hydrogels were studied. The swelling behaviors, swelling kinetics and pH-responsive behaviors of the hydrogels were also evaluated. Owing to the hydrogen bonds and possible covalent bonds between GO and polymer chains, relatively lower content (<0.30. wt%) of GO could be dispersed well in the polymer matrix and enhanced the intermolecular interactions between the components effectively. On the contrary, an excessive amount of GO might form large agglomerates and weakened the interfacial interactions, resulting in the micro-phase separation between the components. Furthermore, the swelling capacities and swelling rates of hydrogels went up with increasing GO loadings to 0.30. wt% and then decreased with further increasing GO loadings. It is worth noting that the hydrogel only containing 0.10. wt% GO exhibited significant improvement of swelling capacity in neutral medium, and could also retain relatively higher swelling capacities to a certain degree at acidic and basic solutions. Therefore, the as-prepared GO-based super-absorbent hydrogels might have potential applications in many areas, such as biomedical engineering, construction engineering and hygienic products. © 2012 Elsevier B.V.

Zeng M.,Wuhan University | Zeng M.,University of Sichuan | Wang J.,Wuhan University | Li R.,Wuhan University | And 5 more authors.
Polymer (United Kingdom) | Year: 2013

Two series of benzoxazine (BOZ) based composites were prepared with graphene oxide (GO) and graphite via in situ intercalative polymerization. Based on isothermal and non-isothermal mode Differential Scanning Calorimetry results, BOZ with the addition of GO could not only decrease the cure temperature, but also increase the cure rate of BOZ. On the contrary, BOZ with the addition of graphite would delay the polymerization of BOZ monomer. It was hypothesized that carboxyl groups of GO acted as weak organic acid which accelerated the ring opening procedure. Interestingly, BOZ/GO composite with 1 wt% GO occupied the least time to form polymer networks, attributing to the catalytic effect and good dispersion of GO. Moreover, BOZ with 1 wt% content of GO had relatively higher glass transition temperature and char yield than those of the corresponding BOZ/graphite sample, which was due to relatively stronger intermolecular interactions between GO and BOZ. © 2013 Elsevier Ltd. All rights reserved.

Wu Y.,Wuhan University | Zeng M.,Wuhan University | Zeng M.,University of Sichuan | Jin H.,Wuhan University | And 5 more authors.
Tribology Letters | Year: 2012

The present work is a generic study to examine the effects of the glass-to-rubber transition of resin matrix on the friction and wear characteristics of zirconium oxide (ZrO 2) reinforced polybenzoxazine nanocomposites, in relation to the content of ZrO 2. The thermal and tribological properties of the nanocomposites were measured by dynamic mechanical thermal analysis (DMA) and friction test, respectively. DMA results revealed that the storage modulus and T g values of the nanocomposites increased with increasing ZrO 2 content to 4 wt%, due to the exceptional mechanical strength of ZrO 2 particles and the interfacial adhesion between ZrO 2 and matrix to restrict the segmental motion of polymer. The friction coefficient (COF) values as a function of applied load (50-750 N) for the nanocomposites under testing temperatures (50, 100, 200, 250, and 300 °C) were measured. Comparable to the pure resin, the nanocomposites possessed relatively higher COF values with the increase of applied pressure under varying temperatures, which resulted from the reinforcement of ZrO 2. It is noted that the nanocomposites containing 4 wt% ZrO 2 occupied relatively higher modulus and glass transition temperature, resulting in better capability to stabilize the friction coefficient and wear rate under the applied conditions. In addition, the friction mechanism of the nanocomposites were proposed based on the experimental and reference results. © Springer Science+Business Media, LLC 2012.

Wu Y.,Wuhan University | Zeng M.,Wuhan University | Zeng M.,University of Sichuan | Xu Q.,Hubei Research Institute of Chemistry | And 4 more authors.
Tribology International | Year: 2012

The present study is to examine the effects of glass-to-rubber transition of resin matrix on the friction and wear characteristics of friction materials, in relation to different types of thermosetting resins. Dynamic mechanical thermal analysis and friction test results revealed that glass-to-rubber transition of thermosetting resins influenced significantly the friction and wear behavior of the composite materials. There was a significant increasing tendency in friction coefficient and wear rate values for all composites when braking temperatures increased to 200 or 250 °C, accompanying the resin matrix converted from glassy state to rubbery state. © 2012 Elsevier Ltd. All rights reserved.

Hubei Expressway Business Development Co. and Haiso Technology Co. | Date: 2013-12-06

A slow release anti-icing material for a bituminous pavement and a method of manufacturing the same. The material includes X, Y and Z components. The X component is a chloride of 80-95 parts. The Y component comprises sodium silicate sodium gluconate and zinc dihydrogen phosphate. The Z component is an acrylate polymer obtained from polymerization of an acrylate monomer, as a cross-linking agent, and a hydrogen containing silicone oil. The manufacturing method includes preparing the X component, preparation the Y component, mixing the X component and the Y component evenly, and encapsulating the surface of the mixture of component X and Y by the component Z evenly through polymerization, to produce the slow release anti-icing material for a bituminous pavement. The anti-icing effects are remarkable for the bituminous pavement, and the material has effects of completely preventing the pavement from icing at 5 to 0 C.

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