It is important to address the challenges posed with the ever-increasing demand for energy supply and environmental sustainability. Activated carbon, which is the common material for commercial supercapacitor electrodes, is currently derived from petroleum-based precursors. This paper presents an effective synthetic method that utilizes waste tires as the precursor to prepare the activated carbon electrodes by the pyrolysis and chemical activation processes. Adjusting the activation parameters can tailor multiple physical properties of the resulting activated carbon, which in turns tunes the performance of the activated carbon electrode. Statistical multiple linear regression and stepwise regression methods are employed to investigate the dependence of the specific capacitance and the rate capability upon the physical properties (such as porosity) of the activated carbon electrode. The specific capacitance of activated carbon electrode is controlled by the micropore volume but independent of the mesopores volume. The rate capability is dominated by the mesopore/micropore volume ratio instead of the absolute value of mesopore volume.

Polymethylmethacrylate (PMMA)/silica nanocomposites are prepared by solution polymerization in this project and the resulting materials are subjected to characterization to evaluate thermal, mechanical, and fire properties. IR results show that both (3-acryloxypropyl)methydimethoxysilane (APMDMOS) and (3-acryloxypropyl)trimethoxysilane (APTMOS) can serve as reagents for the surface modification of silica, while APTMOS performed better than APMDMOS for the modification of the silica surface. Mechanical properties of PMMA/silica nanocomposites prepared by solution blending showed decreased tensile strength and elongation at break, while materials from solution polymerization performed better than PMMA itself. Moreover, all prepared samples have shown improved thermal stabilities versus PMMA. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3844 -3850, 2004

Three polymer/silica nanocomposites were prepared by a single‐screw extrusion approach: poly(methyl methacrylate), polystyrene and polycarbonate/silica nanocomposites. The resulting nanocomposites were subjected to comprehensive studies of mechanical, thermal and flammability properties. All materials showed improved mechanical performance and thermal stabilities, although they are not strictly flame retardant when subjected to fire tests like Oxygen Index or horizontal Bunsen burner tests. However, the nanocomposites showed reduction in peak heat release rates and total heat release when evaluated by cone calorimetry. Moreover, the polycarbonate showed improvement in flammability according to vertical burning tests. All polycarbonate materials subjected to vertical burning testing are V2 rated, but after flame times with 1% silica were significantly reduced. A flame retardant mechanism is proposed in order to understand the relationship between interfacial interaction and flammability of polymer/silica nanocomposites. Copyright © 2006 John Wiley & Sons, Ltd.

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Transparent wood samples were fabricated from an environmentally-friendly hydrogen peroxide (H2O2) bleached basswood (Tilia) template using polymer impregnation. The wood samples were bleached separately for 30, 60, 90, 120 and 150 min to evaluate the effects on the changes of the chemical composition and properties of finished transparent wood. Experimental results showed decreases in cellulose, hemicellulose, and lignin content with an increasing bleaching time and while decreasing each component to a unique extent. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) analysis indicated that the wood cell micro-structures were maintained during H2O2 bleaching treatment. This allowed for successful impregnation of polymer into the bleached wood template and strong transparent wood products. The transparent wood possessed a maximum optical transmittance up to 44% at 800 nm with 150 min bleaching time. Moreover, the transparent wood displayed a maximum tensile strength up to 165.1 ± 1.5 MPa with 90 min bleaching time. The elastic modulus (Er) and hardness (H) of the transparent wood samples were lowered along with the increase of H2O2 bleaching treatment time. In addition, the transparent wood with 30 min bleaching time exhibited the highest Er and H values of 20.4 GPa and 0.45 GPa, respectively. This findings may provide one way to choose optimum degrees of H2O2 bleaching treatment for transparent wood fabrication, to fit the physicochemical properties of finished transparent wood.

Single-walled carbon nanotubes (SWNTs) were modified with polyethylene (PE) prepared by in situ Ziegler-Natta polymerization. Because of the catalyst pretreated on the surface of the SWNTs, the ethylene was expected to polymerize there. Scanning electron microscopy images and solubility measurements showed that the surface of the SWNTs was covered with a PE layer, and a crosslink may have formed between the SWNTs and PE. When the SWNTs covered with a PE layer were mixed with commercialized PE by melt blending, the resulting composite had better mechanical properties than the composite from the SWNTs without a PE layer. The yield strength, the tensile strength and modulus, the strain at break, and the fracture energy of the modified-SWNT/PE composites were improved by 25, 15.2, 25.4, 21, and 38% in

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Transparent wood (TW) was prepared by directly impregnating the wood cell wall and cavity with index-matched prepolymerized methyl methacrylate (MMA). In this process, lignin is retained compared with the preparation of transparent wood in the past, making the production faster and more energy-efficient. The innovation lies in that the prepared transparent wood retains the natural color and texture of the wood while transmitting light, especially under the illumination of a specific light source, which exist as the special visual effects. In order to enhance the practicality of the research and effectively expand the types of home decoration materials, six common wood species with different densities were selected in the experiment. Then the characteristics and mechanisms of wood, that is, color difference, light transmittance, microstructure, changes of chemical functional groups, and tensile strength, before and after PMMA impregnating were compared and analyzed. It is concluded that the light transmittance and mechanical properties of the wood have been improved, and a good synergistic effect between wood and PMMA has been confirmed by the analysis of scanning electron microscopy and infrared spectroscopy. The above highlights make pervious to transparent wood, which has the potential as an excellent functional decorative material.