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Selected Works

Gordon Wallace

Polymer

Articles 1 - 7 of 7

Full-Text Articles in Physical Sciences and Mathematics

Tensile Testing Of Individual Glassy, Rubbery And Hydrogel Electrospun Polymer Nanofibres To High Strain Using The Atomic Force Microscope, Adrian Gestos, Philip G. Whitten, Geoffrey M. Spinks, Gordon G. Wallace Mar 2014

Tensile Testing Of Individual Glassy, Rubbery And Hydrogel Electrospun Polymer Nanofibres To High Strain Using The Atomic Force Microscope, Adrian Gestos, Philip G. Whitten, Geoffrey M. Spinks, Gordon G. Wallace

Gordon Wallace

The production and use of polymer nanofibre assemblies prepared by electrospinning is now widespread. It is known that the tensile properties of electrospun polymer fibres can be different to those of bulk polymers. Here, we report a general method for measuring the tensile properties of individual electrospun nanofibres that employs a commercial atomic force microscope. Methods for preparing samples, force calibration and calculation of tensile stress and strain are described along with error estimation. By appropriate choice of AFM cantilever, it is shown that the tensile stress-strain curves can be measured for glassy, rubbery and gel polymer nanofibres. Testing can …


A Merocyanine-Based Conductive Polymer, Klaudia K. Wagner, Michele Zanoni, Anastasia Elliott, Pawel W. Wagner, Robert P. Byrne, Larisa Florea, Dermot Diamond, Keith Gordon, Gordon G. Wallace, David L. Officer Mar 2014

A Merocyanine-Based Conductive Polymer, Klaudia K. Wagner, Michele Zanoni, Anastasia Elliott, Pawel W. Wagner, Robert P. Byrne, Larisa Florea, Dermot Diamond, Keith Gordon, Gordon G. Wallace, David L. Officer

Gordon Wallace

We report the first example of a conducting polymer with a merocyanine incorporated into the polymer backbone by electropolymerisation of a spiropyran moiety covalently linked between two alkoxythiophene units. Utilising the known metal coordination capabilities of merocyanines, introduction of cobalt ions into the electropolymerisation led to an enhancement of the conductivity, morphology and optical properties of the polymer films.


Conducting Polymer Coated Neural Recording Electrodes, Alexander R. Harris, Simon Morgan, Jun Chen, Robert M. Kapsa, Gordon G. Wallace, Antonio Paolini May 2013

Conducting Polymer Coated Neural Recording Electrodes, Alexander R. Harris, Simon Morgan, Jun Chen, Robert M. Kapsa, Gordon G. Wallace, Antonio Paolini

Gordon Wallace

Neural recording electrodes suffer from poor signal to noise ratio, charge density, biostability and biocompatibility. This paper investigates the ability of conducting polymer coated electrodes to record acute neural response in a systematic manner, allowing in depth comparison of electrochemical and electrophysiological response. Approach. Polypyrrole (Ppy) and poly-3,4-ethylenedioxythiophene (PEDOT) doped with sulphate (SO4) or para-toluene sulfonate (pTS) were used to coat iridium neural recording electrodes. Detailed electrochemical and electrophysiological investigations were undertaken to compare the effect of these materials on acute in vivo recording. Main results. A range of charge density and impedance responses were seen with each respectively doped …


Conducting Polymer Nanoparticles Synthesized In An Ionic Liquid By Chemical Polymerisation, J.M. Pringle, Orawan Ngamna, Jun Chen, Gordon G. Wallace, Maria Forsyth, Douglas Macfarlane Mar 2013

Conducting Polymer Nanoparticles Synthesized In An Ionic Liquid By Chemical Polymerisation, J.M. Pringle, Orawan Ngamna, Jun Chen, Gordon G. Wallace, Maria Forsyth, Douglas Macfarlane

Gordon Wallace

Ionic liquids are ideal media for the synthesis and application of conducting polymers as they can exhibit excellent oxidative and reductive stability, allowing access to potentials outside the smaller electrochemical window of molecular solvent/electrolyte systems. Here we report the first use of an ionic liquid for the chemical synthesis of poly(pyrrole), poly(thiophene) and poly(terthiophene) using a variety of oxidants. The polymers have been analysed by UV–vis spectroscopy, cyclic voltammetry and dynamic light scattering, which shows the particles to be <500 nm diameter. TEM analysis shows the individual poly(thiophene) particles to be <100 nm.


Controlled Deposition Of Polymer Carbon Nanotube Composites Through Inkjet Printing, William Small, Fatemeh Masdarolomoor, Gordon G. Wallace, Marc In Het Panhuis Mar 2013

Controlled Deposition Of Polymer Carbon Nanotube Composites Through Inkjet Printing, William Small, Fatemeh Masdarolomoor, Gordon G. Wallace, Marc In Het Panhuis

Gordon Wallace

The controlled deposition of polyaniline carbon nanotube composites by inkjet printing is reported. It is demonstrated that the sheet resistance and transmittance can be expressed in amount of composite and MWNT material deposited. The most efficient way for improving the sheet resistance while keeping the cost in optical transparency to a minimum is by increasing the total amount of material deposited, rather than increasing MWNT loading fraction.


All-Polymer Battery System Based On Polypyrrole (Ppy)/Para (Toluene Sulfonic Acid) (Pts) And Polypyrrole (Ppy)/Indigo Carmine (Ic) Free Standing Films, Irin Sultana, Md. Mokhlesur Rahman, Jiazhao Wang, Caiyun Wang, Gordon G. Wallace, Hua-Kun Liu Mar 2013

All-Polymer Battery System Based On Polypyrrole (Ppy)/Para (Toluene Sulfonic Acid) (Pts) And Polypyrrole (Ppy)/Indigo Carmine (Ic) Free Standing Films, Irin Sultana, Md. Mokhlesur Rahman, Jiazhao Wang, Caiyun Wang, Gordon G. Wallace, Hua-Kun Liu

Gordon Wallace

In this study, we introduce a novel all-polymer battery system based on conducting polymer (polypyrrole, PPy) doped with dopants of para (toluene sulfonic acid) (pTS) and indigo carmine (IC), respectively. The performance of the systems consisting of polypyrrole-para (toluene sulfonic acid) (PPy-pTS) as cathode and polypyrrole-indigo carmine (PPy-IC) as anode in conjunction with either a polymer based electrolyte or a commercial organic electrolyte of 1M LiPF6 in a 50:50 (v/v) mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC) was evaluated. In the system, all the free-standing PPy-pTS and PPy-IC films were directly used without needing any metal substrate support …


Levetiracetam-Loaded Biodegradable Polymer Implants In The Tetanus Toxin Model Of Temporal Lobe Epilepsy In Rats, Amy J. Halliday, Toni E. Campbell, Timothy S. Nelson, Karen J. Mclean, Gordon G. Wallace, Mark J. Cook Mar 2013

Levetiracetam-Loaded Biodegradable Polymer Implants In The Tetanus Toxin Model Of Temporal Lobe Epilepsy In Rats, Amy J. Halliday, Toni E. Campbell, Timothy S. Nelson, Karen J. Mclean, Gordon G. Wallace, Mark J. Cook

Gordon Wallace

Approximately one-third of people with epilepsy receive insufficient benefit from currently available anticonvulsant medication, and some evidence suggests that this may be due to a lack of effective penetration into brain parenchyma. The current study investigated the ability of biodegradable polymer implants loaded with levetiracetam to ameliorate seizures following implantation above the motor cortex in the tetanus toxin model of temporal lobe epilepsy in rats. The implants led to significantly shorter seizures and a trend towards fewer seizures for up to 1 week. The results of this study indicate that drug-eluting polymer implants represent a promising evolving treatment option for …