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Australian Institute for Innovative Materials - Papers

2013

Composites

Articles 1 - 8 of 8

Full-Text Articles in Physical Sciences and Mathematics

1-3 Piezoelectric Composites For High-Temperature Transducer Applications, Lili Li, Shujun Zhang, Zhuo Xu, Fei Wen, Xuecang Geng, Hyeong Jae Lee, Thomas R. Shrout Jan 2013

1-3 Piezoelectric Composites For High-Temperature Transducer Applications, Lili Li, Shujun Zhang, Zhuo Xu, Fei Wen, Xuecang Geng, Hyeong Jae Lee, Thomas R. Shrout

Australian Institute for Innovative Materials - Papers

High-temperature Pb(Zr,Ti)O3/epoxy 1-3 composites were fabricated using the dice and fill method. The epoxy filler was modified with glass spheres in order to improve the thermal reliability of the composites at elevated temperatures. Temperature-dependent dielectric and electromechanical properties of the composites were measured after ageing at 250 °C with different dwelling times. Obvious cracks were observed and the electrodes were damaged in the composite with unmodified epoxy after 200 h, leading to the failure of the composite. In contrast, composites with >12 vol% glass sphere loaded epoxies were found to exhibit minimal electrical property variation after ageing for 500 h, …


Tunable Negative Permittivity Behavior And Conductor-Insulator Transition In Dual Composites Prepared By Selective Reduction Reaction, Zi-Dong Zhang, Run-Hua Fan, Zhi-Cheng Shi, Shi-Bing Pan, Ke-Lan Yan, Kang-Ning Sun, Jing-De Zhang, Xiang-Fa Liu, Xiaolin Wang, S X. Dou Jan 2013

Tunable Negative Permittivity Behavior And Conductor-Insulator Transition In Dual Composites Prepared By Selective Reduction Reaction, Zi-Dong Zhang, Run-Hua Fan, Zhi-Cheng Shi, Shi-Bing Pan, Ke-Lan Yan, Kang-Ning Sun, Jing-De Zhang, Xiang-Fa Liu, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

We use a selective reduction reaction to fabricate a new kind of dual composite, which has a "composite-within-a-composite" structure. Based on the different reduction behavior of Fe2O3, an Fe-rich structure (Fe-Fe3O4-Al2O3) is formed in an Al-rich structure (FeAl2O4-Al2O3). The Fe-rich structure can bring down the concentration of free electrons to reduce the energy loss, without losing its metallic behaviour at the same time. Near the percolation threshold, a conductor-insulator transition appears and the dual composites show totally different electromagnetic responses, which can be well explained by effective medium theory. By controlling the parameters of the selective reduction process, we can …


Covalently Linked Biocompatible Graphene/Polycaprolactone Composites For Tissue Engineering, Sepidar Sayyar, Eoin Murray, Brianna C. Thompson, Sanjeev Gambhir, David L. Officer, Gordon G. Wallace Jan 2013

Covalently Linked Biocompatible Graphene/Polycaprolactone Composites For Tissue Engineering, Sepidar Sayyar, Eoin Murray, Brianna C. Thompson, Sanjeev Gambhir, David L. Officer, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Two synthesis routes to graphene/polycaprolactone composites are introduced and the properties of the resulting composites compared. In the first method, mixtures are produced using solution processing of polycaprolactone and well dispersed, chemically reduced graphene oxide and in the second, an esterification reaction covalently links polycaprolactone chains to free carboxyl groups on the graphene sheets. This is achieved through the use of a stable anhydrous dimethylformamide dispersion of graphene that has been highly chemically reduced resulting in mostly peripheral ester linkages. The resulting covalently linked composites exhibit far better homogeneity and as a result, both Young's modulus and tensile strength more …


A Facile Route To Synthesize Transition Metal Oxide/Reduced Graphene Oxide Composites And Their Lithium Storage Performance, Chongjun Zhao, Shulei Chou, Yunxiao Wang, Cuifeng Zhou, Hua-Kun Liu, S X. Dou Jan 2013

A Facile Route To Synthesize Transition Metal Oxide/Reduced Graphene Oxide Composites And Their Lithium Storage Performance, Chongjun Zhao, Shulei Chou, Yunxiao Wang, Cuifeng Zhou, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Transition metal oxide (Mn3O4, Fe2O3, Co3O4, and ZnO) and reduced graphene oxide (RGO) composites were successfully synthesized via a hydrothermal method using the direct reaction between the corresponding metal powder and graphene oxide (GO). In this process, the GO can be reduced by transition metal powder in water, and the nanosized metal oxide can be obtained, and homogeneously mixed with and wrapped by RGO to form a metal oxide/RGO composite at the same time. X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning and transmission electron microscopy were used to characterize the as-prepared materials. The different experimental parameters, including reactants, …


Surface Modification Of Polypyrrole/Biopolymer Composites For Controlled Protein And Cellular Adhesion, Paul J. Molino, Binbin Zhang, Gordon G. Wallace, Timothy Hanks Jan 2013

Surface Modification Of Polypyrrole/Biopolymer Composites For Controlled Protein And Cellular Adhesion, Paul J. Molino, Binbin Zhang, Gordon G. Wallace, Timothy Hanks

Australian Institute for Innovative Materials - Papers

The ability to control the interaction between proteins and cells with biomaterials is critical for the effective application of materials for a variety of biomedical applications. Herein, the surface modification of the biological dopant dextran sulphate-doped polypyrrole (PPy-DS) with poly(ethylene glycol) to generate a biomaterial interface that is highly resistant to protein and cellular adhesion is described. Thiolated poly(ethylene glycol) (PEG-thiol) was covalently bound to PPy-DS backbone via a thiol-ene reaction. The surface resistance to an extracellular matrix protein fibronectin increased with increasing molecular weight and concentration of PEG-thiol, and was further optimised via increasing the reaction temperature and the …


Cell Attachment And Proliferation On High Conductivity Pedot-Glycol Composites Produced By Vapour Phase Polymerisation, Elise M. Stewart, Manrico Fabretto, Mischa Mueller, Paul J. Molino, Hans J. Griesser, Robert D. Short, Gordon G. Wallace Jan 2013

Cell Attachment And Proliferation On High Conductivity Pedot-Glycol Composites Produced By Vapour Phase Polymerisation, Elise M. Stewart, Manrico Fabretto, Mischa Mueller, Paul J. Molino, Hans J. Griesser, Robert D. Short, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

High conductivity poly(3,4-ethylene dioxythiophene) (PEDOT) was synthesised using vacuum vapour phase polymerization (VVPP). The process produces PEDOT composites which incorporate glycol within the polymer. To assess biocompatibility, a suite of analytical techniques were utilised in an effort to characterise the level of glycol present and its impact on cell attachment and proliferation. A small decrease in fibroblast cell attachment and proliferation was observed with increasing glycol content within the PEDOT composite. Keratinocyte cell attachment and proliferation by comparison showed an increase. As such, the results herein indicate that cell attachment and proliferation depends on the individual cell lines used and …


Carbon Nanotube-Reduced Graphene Oxide Composites For Thermal Energy Harvesting Applications, Mark S. Romano, Na Li, Dennis Antiohos, Joselito M. Razal, Andrew Nattestad, Stephen Beirne, Shaoli Fang, Yongsheng Chen, Rouhollah Jalili, Gordon G. Wallace, Ray Baughman, Jun Chen Jan 2013

Carbon Nanotube-Reduced Graphene Oxide Composites For Thermal Energy Harvesting Applications, Mark S. Romano, Na Li, Dennis Antiohos, Joselito M. Razal, Andrew Nattestad, Stephen Beirne, Shaoli Fang, Yongsheng Chen, Rouhollah Jalili, Gordon G. Wallace, Ray Baughman, Jun Chen

Australian Institute for Innovative Materials - Papers

By controlling the SWNT-rGO electrode composition and thickness to attain the appropriate porosity and tortuosity, the electroactive surface area is maximized while rapid diffusion of the electrolyte through the electrode is maintained. This leads to an increase in exchange current density between the electrode and electrolyte which results in enhanced thermocell performance.


Manganosite-Microwave Exfoliated Graphene Oxide Composites For Asymmetric Supercapacitor Device Applications, Dennis Antiohos, Kanlaya Pingmuang, Mark Romano, Stephen Beirne, Tony C. Romeo, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Sukon Phanichphant, Jun Chen Jan 2013

Manganosite-Microwave Exfoliated Graphene Oxide Composites For Asymmetric Supercapacitor Device Applications, Dennis Antiohos, Kanlaya Pingmuang, Mark Romano, Stephen Beirne, Tony C. Romeo, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Sukon Phanichphant, Jun Chen

Australian Institute for Innovative Materials - Papers

Graphene based materials coupled with transition metal oxides are promising electrode materials in asymmetric supercapacitors owing to their unique properties which include high surface area, good chemical stability, electrical conductivity, abundance, and lower cost profile over time. In this paper a composite material consisting of graphene oxide exfoliated with microwave radiation (mw rGO), and manganosite (MnO) is synthesised in order to explore their potential as an electrode material. The composite material was characterised by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to explore …