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Rhodes, Susan M. "Electrically Conductive Polymer Composites." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1194556747.
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Shahbaz, Tabari Zahra. "Conductive polymers : a route for sustainability." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-19358.
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The concept of sustainable use of materials defines as utilizing raw material as less aspossible and introducing less toxic substances to the environment as well. Smartmaterials are one route for sustainability, as they have optimal performance in relation tomaterial composition. New technologies can be developed by using smart materials. Onearea is the development of smart textiles, meaning the incorporation of electronicfunctions in textiles. These functions can be used for human protection or monitoring ofhealth.Conductivity is a key factor in smart textiles. The aim of this report is to identifyelectrically conductivity of textile fibres in conjunction with conductive polymer(polyaniline). By applying conductive polymer (polyaniline ink) on textiles fabric andfibres it is possible to obtain conductive textile products. This project focuses on thedevelopment of conductive fibres by coating of an individual fibre or a few differenttypes of fabric with conductive polymer polyaniline dispersion in water and toluene assolvent. Various situations have been taken into consideration and investigated fordifferent concentration to different times of coating and deposit thickness. Performanceon resistivity calculation led to find optimum concentration and coating numbers anddeposit thickness. Based on the inventory, a qualitative resistivity analysis is carried outfor the purpose of identifying which combination of concentration and times of coating inthe case of woven types fibre or coating thickness in the case of non woven types offabrics as well as the types of fabrics would provide the better conductivity properties in the textile fibres and fabrics.
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Lay, Makara. "Conductive nanopaper from cellulose nanofibers and conductive polymers and/or carbon nanotubes." Doctoral thesis, Universitat de Girona, 2017. http://hdl.handle.net/10803/401711.
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Coming from renewable and sustainable raw materials, nanocelluloses are rapidly emerging as one of the most promising future materials. Recently, the use of nanocellulose nanocomposites in flexible electrodes, biosensors or supercapacitors it is been studied.
The main objective of this thesis is to produce conductive nanopapers from cellulose nanofibers (CNF) or bacterial cellulose (BC) and tree different conductive materials: polypyrrole (PPy), poly(3,4-ethylenedioxythiophene : polystyrene sulfonate (PEDOT:PSS) and multi-walled carbon nanotubes (MWCNT).
The structure and morphology of nanocomposites were studied, as well as their thermal, mechanical, and electrical conductivity properties. The results revealed the semiconductor or conductor character of the obtained nanocomposites, with specific capacitances up to 300 F g-1 for CNF-PPy and CNF-PEDOT:PSS-PPy nanocomposites. This work demonstrates the feasibility of using cellulose nanofibers in the field of green and flexible electronics, biosensors, and energy storage devices<br>Les nanofibres de cel·lulosa són un dels materials del futur, gràcies al seu origen natural i renovable, i per les seves propietats físico-químiques, i mecàniques. Recentment, s’està estudiant el seu ús en elèctrodes flexibles, biosensors o supercapacitants.
L’objectiu central de la tesis és produir nanopapers conductors a partir de nanofibres de cel·lulosa (CNF) o de cel·lulosa bacteriana (BC), i tres tipus de càrrega conductora, el polipirrol (PPy), el poli(3-4-etilendioxitiofè):poliestirè sulfonat (POEDOT:PSS) i els nanotubs de carboni de paret múltiple (MWCNT).
S’ha avaluat l’estructura i morfologia dels materials nanocompòsits, així com les seves propietats tèrmiques, mecàniques i elèctriques. Els resultats mostren el caràcter semiconductor o conductor dels nanocompòsits obtinguts, amb capacitàncies específiques de més de 300 F·g-1 per als nanocompòsits de CNF-PPy i CNF-PEDOT:PSS-PPy. Es demostra la viabilitat de l’ús de nanofibres de cel·lulosa per la fabricació de productes electrònics flexibles, biosensors, o com a dispositius d’emmagatzematge d’energia
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Rohanifar, Ahmad. "Conductive Polymers for Electrochemical Analysis and Extraction." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1544809010837595.
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Karwa, Anupama. "Printing studies with conductive inks and exploration of new conducting polymer compositions /." Link to online version, 2006. https://ritdml.rit.edu/dspace/handle/1850/1318.
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Moody, David Jesse II. "Synthesis and characterization of novel electrically conductive polymers." Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/30270.
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Martins, Bruno Miguel Rocha. "Electrochemical supercapacitors of conductive polymers and their composites." Master's thesis, Faculdade de Ciências e Tecnologia, 2014. http://hdl.handle.net/10362/13633.
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Fukushima, Motoo. "Synthesis and Electrical Conductive Properties of Organosilicon Polymers." Kyoto University, 1999. http://hdl.handle.net/2433/182375.
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Jafarzadeh, Shadi. "Functional composite coatings containing conducting polymers." Doctoral thesis, KTH, Yt- och korrosionsvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-155132.
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Organic coatings are widely used to lower the corrosion rate of metallic structures. However, penetration of water, oxygen and corrosive ions through pores present in the coating results in corrosion initiation and propagation once these species reach the metal substrate. Considering the need for systems that offer active protection with self-healing functionality, composite coatings containing polyaniline (PANI) conducting polymer are proposed in this study. In the first phase of my work, PANI was synthesized by various methods and characterized. The rapid mixing synthesis method was chosen for the rest of this study, providing PANI with high electrical conductivity, molecular structure of emeraldine salt, and morphology of spherical nanoparticles. PANIs doped with phosphoric and methane sulfonic acid revealed hydrophilic nature, and I showed that by incorporating a long-chain alkylphosphonic acid a hydrophobic PANI could be prepared. The second phase of my project was dedicated to making homogenous dispersions of PANI in a UV-curable resin based on polyester acrylate (PEA). Interfacial energy studies revealed the highest affinity of PEA to PANI doped with phosphoric acid (PANI-PA), and no attractive or long-range repulsive forces were measured between the PANI-PA surfaces in PEA.This is ideal for making conductive composites as, along withno aggregation tendency, the PANI-PA particles might come close enough to form an electrically connected network. Highly stable PEA/PANI-PA dispersions were prepared by pretreatment of PANI-PA in acetone followed by mixing in PEA in small portions under pearl-milling. The third phase of my project dealt with kinetics of the free radical polymerization that was utilized to cure the PEA/PANI-PA mixture. UV-vis absorption studies suggested a maximum allowed PANI-PA content of around 4 wt.% in order not to affect the UV curing behavior in the UV-C region. Real-time FTIR spectroscopy studies, using a laboratory UV source, revealed longer initial retardation of the photocuring and lower rates of crosslinking reactions for dispersions containing PANI-PA of higher than 3 wt.%. The presence of PANI-PA also made the formulations more sensitive to changes in UV light intensity and oxygen inhibition during UV curing. Nevertheless, curing of the dispersions with high PANI-PA content, of up to 10 wt.%, was demonstrated to be possible at either low UV light intensities provided the oxygen replenishment into the system was prevented, or by increasing the UV light intensity to very high levels. In the last phase of my project, the PEA and PEA/PANI-PA coatings, cured under high intensity UV lamps, were characterized. SEM analysis showed small PANI-PA particles to be closely packed within the matrix, and the electrical conductivity of the composite films was measured to be in the range of semiconductors. This suggested the presence of a connected network of PANI-PA, as confirmed by investigations of mechanical and electrical variations at the nanoscale by PeakForce TUNA AFM. The data revealed the presence of a PEA-rich layer at the composite-air interface, and a much higher population of the conductive network within the polymer matrix. High current signal was correlated with a high elastic modulus, consistent with the level measured for PANI-PA, and current-voltage studies on the conductive network showed non-Ohmic characteristics. Finally, the long-term protective property of the coatings was characterized by OCP and impedance measurements. Short-term barrier-type corrosion protection provided by the insulating PEA coating was turned into a long-term and active protection by addition of as little as 1 wt.% PANI-PA. A large and stable ennoblement was induced by the coatings containing PANI-PA of up to 3 wt.%. Higher content of PANI-PA led to poorer protection, probably due to the hydrophilicity of PANI-PA facilitating water transport in the coating and the presence of potentially weaker spots in the film. An iron oxide layer was found to fully cover the metal surface beneath the coatings containing PANI-PA after final failure observed by electrochemical testing.<br><p>QC 20141103</p>
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Chen, Kun. "INVESTIGATION OF GRAPHENE-BASED MULTI-FILLER ELECTRICALLY CONDUCTIVE ADHESIVE MATERIAL." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1555091658254182.
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Cakar, Ilknur. "Conductive Coating Materials." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/2/12607410/index.pdf.
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In this study, electrically conductive coating materials composed of epoxy resin and carbon black (CB) were prepared by applying two different mixing techniques (Grinding and Mechanical Mixing). The effect of carbon black addition, ultrasonication, mixing type and surface modification of carbon black on the morphologies, electrical and mechanical properties of the composites were investigated.
According to test results, Grinding Method is much more efficient and for this method, percolation concentration was found as 2 vol %. The electrical resistivity value obtained at this composition is around 107 ohm.cm. Also, for the samples prepared by Grinding Method, the hardness increased by adding conductive filler, but the impact energy and adhesive strength decreased with increasing carbon black content.
Ultrasonication was applied to the samples containing 2 vol % CB obtained by Grinding Method to reduce the electrical resistivity further. Three different ultrasonic mixing times were tried, however, no positive effect was observed on electrical and mechanical properties.
Since the addition of carbon black has a negative effect on the processability of the mixture, it was aimed to obtain desired conductivity value at lower percolation concentration by modifying carbon black surface with different silane coupling agents and formamide. The best result in terms of electrical conductivity was obtained for the materials produced with formamide treated carbon black by Grinding Method. At 1 vol % concentration, the electrical resistivity was found as approximately 106 ohm.cm which is three orders smaller than the resistivity of materials prepared with untreated carbon black.
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Sayre, Curtis N. "Self-assembled monolayers and their effect on conductive polymers." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/30896.
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Falk, Daniel. "Patterning of Highly Conductive Conjugated Polymers for Actuator Fabrication." Thesis, Linköpings universitet, Biosensorer och bioelektronik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-130465.
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Trilayer polypyrrole microactuators that can operate in air have previously been developed. They consist of two outer layers ofthe electroactive polymer polypyrrole (PPy) and one inner layer of a porous poly(vinylidene flouride) (PVDF) membranecontaining a liquid electrolyte. The two outer layers of PPy are each connected with gold electrodes and separated by the porousPVDF membrane. This microtool is fabricated by bottom-up microfabrication However, porous PVDF layer is not compatible with bottom upmicrofabrication and highly swollen SPE suffers from gold electrode delamination. Hence, in this MSc project/thesis a novelmethod of flexible electrode fabrication with conducting polymers was developed by soft lithography and drop-on-demandprinting. The gold electrodes were replaced by patterned vapor phase polymerized (VPP) poly(3,4-ethylenedioxythiophene) (PEDOT)electrodes due to its high electrical conductivity and versatile process ability. The replacement of the stiff gold electrodes byflexible and stretchable PEDOT allowed high volume change of the material and motions. The PEDOT electrodes werefabricated by patterning the oxidant iron tosylate using microcontact printing and drop-on-demand printing. Moreover, thePVDF membrane has been replaced by a nitrile butadiene rubber/poly(ethylene oxide) semi-interpenetrating polymer network(IPN) to increase ion conductivity and strechability and hence actuator performance.
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Auditto, Sanjana. "Synthesis of organic conductive polymers to struggle bacterial infections." Electronic Thesis or Diss., Aix-Marseille, 2022. http://www.theses.fr/2022AIXM0179.
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Les biofilms sont à l'origine de nombreux problèmes industriels, sanitaires et domestiques conduisant à d’intenses activités de recherche pour concevoir des solutions pour lutter contre leur formation et développement. Deux voies sont classiquement utilisées pour résoudre ces problèmes, soit l’utilisation de polymères anti-salissures soit des surfaces antibactériennes agissant par effet de contact ou par libération continue de biocides. Par ailleurs, des surfaces sensibles à divers stimuli (microenvironnement, lumière, ondes acoustiques etc.) ont été développées pour libérer de manière contrôlée les agents biocides. De plus, l’action d’un potentiel électrique (effet bioélectrique) a suscité un intérêt pour perturber les biofilms, mais reste sous-exploité. C’est dans ce contexte que s’inscrit ce travail avec le développement de surfaces électrostimulables biocompatibles à partir soit de (i) monocouches auto-assemblées (SAMs) déposées sur électrodes de titane ou d’or, (ii) polymères conducteurs (PCs) fonctionnalisés, pour empêcher l'adhésion/tuer les bactéries. Les SAMs à base de phosphoniums ont démontrées d’intéressantes propriétés antibactériennes, sans libération d’agent biocide, contre des souches Gram positive et négative (S. aureus, K. pneumoniae). D’autres part des films minces d’homo- et copolymères de PCs, à base de pyrrole fonctionnalisés par des phosphoniums, ont été obtenus par électropolymérisation et analysés en modifiant et en appliquant un ensemble de paramètres et testés comme antibactérien. Enfin, des phosphoniums hydrophiles ont été synthétisés et des études préliminaires ont mis en évidence leur intérêt potentiel comme vecteurs de médicaments<br>Bacterial biofilms are in the background of many industrial, health and domestic adverse effects with economic losses leading to intensive research to design solutions to combat their formation and development. Two routes are commonly used to solve these issues, one aiming at preventing the adhesion of bacteria and the other at inhibiting and killing adhered microorganisms. Recent work has been done in that direction with the use of polymer-based antifouling or antibacterial surfaces acting either by contact effect or continuous release of bacterial substances. Besides, responsive surfaces to various stimuli (microenvironment, light, acoustic waves, etc.) have been developed to release biocides in a controlled way. In addition, the use of an electrical potential (bioelectric effect) has aroused interest to disrupt biofilms but remains underexploited. The present work focuses on the development of biocompatible electrostimulable surfaces based on either (i) self-assembled monolayers (SAMs) deposited on titanium or gold electrodes, or (ii) functionalized conductive polymers (CPs), to prevent adhesion and/or kill bacteria. Phosphonium-based SAMs have demonstrated interesting antibacterial properties, without release of biocidal agent, against Gram positive and negative strains (S. aureus, K. pneumoniae). In addition, thin films of homo- and copolymers of phosphonium-based pyrrole CPs were obtained by electropolymerization, and analyzed by modifying and applying a set of parameters and tested as antibacterial coatings. Lastly, hydrophilic phosphoniums have been synthesized and preliminary studies have highlighted their potential use as nanocarriers for drug delivery
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Wells, Richard. "THE EFFECTS OF ADDING INHERENTLY CONDUCTIVE POLYMERS TO SILVER-FILLED EPOXIES." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1166414622.
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Breakspear, S. "The growth, morphology and corrosion resistance of modified films of polypyrrole." Thesis, University of Portsmouth, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271450.
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Electroactive, or 'conductive', polymers are a rapidly expanding area of research with proposed applications ranging from batteries or electronic circuitry to artificial muscles and actuators. An emerging application for these materials is as constituents of corrosion resistant coatings. An important factor in any corrosion resistant coating is the level of porosity it possesses. Minimisation of porosity may be highly desirable for the production of highly protective films. This work aims to study methods for controlling the porosity of polypyrrole films for their possible use as corrosion resistant coatings. It has been observed that surfactants can modify the structure and morphology of polypyrrole on inert substrates such as platinum or indium-tin oxide glass, and on the non-inert substrate mild steel. This has involved the study of the conditions necessary for polymer deposition on mild steel where the tendency for metal dissolution competes with the polymerisation reaction. Corrosion studies were carried out, firstly, to assess the corrosion potentials for such films and, secondly, via Tafel extrapolation to determine the effects of film thickness and anionic surfactant concentration on the corrosion rates obtained. Further corrosion studies were performed on polypyrrole films with additions of molybdate corrosion inhibitor species and anionic surfactants. It was found that polypyrrole with additions of anionic surfactants had little or no effect on the corrosion characteristics of mild steel in saline environments. However, in the presence of molybdate and certain levels of surfactants, excellent corrosion resistance characteristics were observed. It is proposed that the reduction of polypyrrole occurs at large negative corrosion potentials, resulting in the formation of an insulating polymer film that is incapable of acting as a site for displaced corrosion reactions around which many of the theories of electro active polymer corrosion protection have previously been based.
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Li, Buxuan. "Synthesis and characterization of high thermal conductive polymers and fabrication of polymer based thermal strap." Thesis, Massachusetts Institute of Technology, 2021. https://hdl.handle.net/1721.1/130863.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, February, 2021<br>Cataloged from the official PDF version of thesis.<br>Includes bibliographical references (pages 66-70).<br>Polymers have infiltrated almost every aspect of modern technology. Without polymer products, the society would look very different. As one of the most important and common engineering materials, traditional polymers are both electrically and thermally insulating, due to its organic nature and amorphous structures. In the late 20th century, electrically conductive polymers has been discovered. Thermally conductive polymers, however, were not demonstrated until the recent decades. Polymers are shown to have great potential in thermal conduction, even divergent thermal conductivity in theory. This counterintuitive finding is attributed to its one-dimensional periodic structure, where repeating monomers are connected by strong covalent bonds.<br>Researchers have learned that special dynamics exist in non-linear one-dimensional chains since the Fermi-Pasta-Ulam-Tsingou report, where the evolution of state space was found to be non-ergodic, enabling an infinite long lifetime of excitations. As a result, such 1D nonlinear system favors scatter-free phonon transport. Molecular dynamics simulation shows a single polyethylene (PE) chain could have divergent thermal conductivity. Calculations from first principle also confirm the thermal conductivity is approximately 160 W/mK for bulk PE and 1400 W/mK for a single PE chain, with a three phonon process taken into consideration. In experiments, researchers measured enhanced thermal conductivity in stretched PE in the 1970s. In the last decades, researchers have made progress by demonstrating PE nanofibers with a thermal conductivity of over 100 W/mK. Recently, 2D PE films were fabricated and measured to have metal-like thermal conductivity of over 60 W/mK.<br>With all these progresses, in this thesis, we aimed to develop scalable polyethylene films with high thermal conductivity and investigating temperature-dependent thermal transport properties. A differential steady state method was used to measure the thermal conductivity of the synthesized PE films. A thermal annealing of PE films was performed along with the temperature dependence test where a transition temperature was identified. Below the transition temperature, thermal annealing increased the thermal conductivity at room temperature. Above the transition temperature, thermal annealing irreversibly decreased the thermal conductivity. Our PE films featured reasonable thermal conductivity of 20~60 W/mK depending on draw ratio and much lower density comparing to metals such as copper and aluminum. A potential application of such films is a light-weight thermal strap, which is important for space technologies.<br>We designed a strategy to overcome the issue that such films have a poor cross-plane thermal conductivity. We proved the idea based on both simulation and experiments. In simulations, we derived a steady state solution of a full-size physical device with conduction and radiation included. In experiments, we conducted a unit test on laboratory scale samples and argued its ability of scaling up by showing that multilayer PE films performed as expected.<br>by Buxuan Li.<br>S.M.<br>S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering
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Guo, Jiao. "Development of Ion Conductive Polymer Gel Electrolytes and Their Electrochemical and Electromechanical Behavior Studies." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1279140041.
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Qayyum, M. M. B. "Organic electronic materials : electroreticulated conductive polymers and potential organic superconductors." Thesis, London South Bank University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618648.
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Cottrill, Michael C. W. "Factors affecting the characteristics of heating devices employing conductive polymers." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/10314.
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This study centres on conductive polymers with particular reference to those exhibiting positive temperature coefficient of resistance (PTC) behaviour. Applications of PTC polymers are identified including, with special relevance to this study, automotive applications. The electrical properties and the structure of a particular conductive polymer that has a carbon black conductive filler and exhibits a positive temperature coefficient characteristic, have been measured. Early problems affecting the testing and service performance of these devices are described. Initial concepts of the factors affecting their structure and performance are outlined. The importance of the characteristic known as resistance linearity is described and its important relationship with device performance is noted. The results of a literature survey are detailed. Typical materials and manufacturing processes employed for the type of heater circuit central to this study are described. The results of initial testing and analysis of PTC heater circuits in relation to manufacturing process variables, ageing tests and service failure are summarised. The results of further testing of heater samples and analysis using advanced techniques including Fourier transform IR spectroscopy (FTIR), Calorimetric analysis with scanning microscopy (CASM), Auger electron spectroscopy (AES), Static secondary ion mass spectrometry (SSIMS) and Laser microprobe mass spectrometry (LIMA) are given. The structure of the PTC polymer used in construction of the heater circuit is examined with a high resolution scanning electron microscope (FEGSEM) and the distribution of the carbon filler is determined. Structural changes and changes in the distribution of the carbon resulting from thermal conditioning and other stresses are investigated. A cause of functional failure of heater circuits in service has been identified. Conclusions have been drawn and further work proposed.
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Honorato, Ana Maria Borges. "Conductive Polymers Derived Heteroatom Doped Carbon Catalysts forOxygen Reduction Reaction." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1607446593560503.
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Soh, Tedric. "Conductive polymer coating for corrosion protection of steel." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112584.
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There is an increasing interest in exploring the use of conductive polymers for protecting metals from corrosion. The corrosion resistance of steel coated with the conductive polymer polypheneylenevinylene (PPV) is studied. The corrodant used is deaerated 1% w/w NaCl(aq).<br>The PPV coating is deposited by a homemade spinning coater. The effect of substrate microstructure and surface treatment on PPV coating morphology is investigated. The morphology and surface roughness of the coating are measured by Atomic Force Microscopy (AFM). The PPV coating thickness and substrate surface roughness are measured by profilometer.<br>Open Circuit Potential (OCP), electrochemical impedance spectroscopy (EIS), linear potentiodynamic voltammetry (Tafel) and optical microscopy were used to characterize the structure and properties of the coatings. The correlation between the coating thickness, the surface treatment of the steel substrate prior to coating, and the corrosion behaviour of PPV coated steel was investigated.<br>Under the condition of our studies, the level of pH in the solution used for corrosion testing has the strongest effect on the corrosion behaviour of PPV coated steel.
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Tang, Qingmeng. "Preparation and Characterization of Electrically Conductive Graphene-Based Polymer Nanocomposites." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1386260373.
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Inaoka, Seiji. "A study of electronically conductive polymers : substituted dithieno[3,4-B:3',4'-d]thiophenes and substrate modification with monomer adsorbates." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/27338.
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Neuendorf, Annette J., and n/a. "High Pressure Synthesis of Conducting Polymers." Griffith University. School of Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040218.112214.
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An experimental investigation of the high pressure synthesis of water soluble, self doping conducting polymers is presented. 2- And 3-aminobenzenesulfonic acid and the respective sodium sulfonates have been polymerised. Optimal polymerisation conditions have been determined with respect to yield, conductivity and molecular weight. Reaction parameters such as oxidant, pressure, catalysts, reaction time and temperature and the use of additives were investigated. The minimum pressure required for polymerisation was 7 kbar. An increase in pressure had a negligible effect on polymer characteristics. The polymers were generated in aqueous, non-acidic media, to ensure they were selfdoping when characterised. Conductivities of between 10-6 Scm-1 and 10-3 Scm-1 were measured. The sulfonate salts reacted faster than the sulfonic acids and for both a longer reaction time resulted in higher yields and conductivities. These polymers were completely water soluble, of high molecular weight and able to be cast as thin films. The arylamines 5- and 8-aminonaphthalene-2-sulfonic acid and their respective sodium sulfonates were polymerised at elevated pressure. The naphthalene sulfonate salts polymerised at atmospheric pressure, but displayed a higher molecular weight when reacted under pressure. Generally the naphthalene monomers reacted similarly to the benzene monomers, although there were some differences. Conductivity and yield decreased with increased reaction times and the use of 0.1M equivalents of ferrous sulfate had an negligible effect on the polymers. The polynaphthalenes were highly water soluble, self doping and had conductivities in the order 10-5 to 10-3 Scm-1. A measurement of the activation volume for the polymerisation of 2-methoxyaniline and sodium 8-aminonaphthalene-2-sulfonate was performed. These were determined to be -44 ± 3 cm3mol-1 and -62 ± 10 cm3mol-1 respectively. These large negative values are consistent with rate limiting monomer oxidation.
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Neuendorf, Annette J. "High Pressure Synthesis of Conducting Polymers." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/366536.
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An experimental investigation of the high pressure synthesis of water soluble, self doping conducting polymers is presented. 2- And 3-aminobenzenesulfonic acid and the respective sodium sulfonates have been polymerised. Optimal polymerisation conditions have been determined with respect to yield, conductivity and molecular weight. Reaction parameters such as oxidant, pressure, catalysts, reaction time and temperature and the use of additives were investigated. The minimum pressure required for polymerisation was 7 kbar. An increase in pressure had a negligible effect on polymer characteristics. The polymers were generated in aqueous, non-acidic media, to ensure they were selfdoping when characterised. Conductivities of between 10-6 Scm-1 and 10-3 Scm-1 were measured. The sulfonate salts reacted faster than the sulfonic acids and for both a longer reaction time resulted in higher yields and conductivities. These polymers were completely water soluble, of high molecular weight and able to be cast as thin films. The arylamines 5- and 8-aminonaphthalene-2-sulfonic acid and their respective sodium sulfonates were polymerised at elevated pressure. The naphthalene sulfonate salts polymerised at atmospheric pressure, but displayed a higher molecular weight when reacted under pressure. Generally the naphthalene monomers reacted similarly to the benzene monomers, although there were some differences. Conductivity and yield decreased with increased reaction times and the use of 0.1M equivalents of ferrous sulfate had an negligible effect on the polymers. The polynaphthalenes were highly water soluble, self doping and had conductivities in the order 10-5 to 10-3 Scm-1. A measurement of the activation volume for the polymerisation of 2-methoxyaniline and sodium 8-aminonaphthalene-2-sulfonate was performed. These were determined to be -44 ± 3 cm3mol-1 and -62 ± 10 cm3mol-1 respectively. These large negative values are consistent with rate limiting monomer oxidation.<br>Thesis (PhD Doctorate)<br>Doctor of Philosophy (PhD)<br>School of Science<br>Full Text
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Wang, Jianli. "Synthesis and characterization of conductive and soluble side-chain blue fluorescent polymers." HKBU Institutional Repository, 2013. https://repository.hkbu.edu.hk/etd_oa/14.
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Semiconducting polymers had been well studied and applied in many research areas. They are such as electroactive actuators, electrochromic materials, microwave-absorbent coatings, polymer solar cells, polymer light-emitting diodes, etc. Traditional semiconductors are metals/oxides and they are expensive, toxic and harmful to the environment. Compared to the traditional n-conjugated main-chain polymers, side-chain conductive polymers have a lower volume percentage of the charge transport moieties yet they possess advantages such as excellent mechanical strength, good rheological properties, solubility in common organic solvents and purer emission hue. Furthermore, the performances of the side-chain semiconducting polymers can be engineered easily by changing their composition or by choosing an appropriate additional polymerization method. As a result, several series of soluble, semiconducting and luminescent side-chain homopolymers and copolymers have been synthesized and characterized. In this thesis, several series of vinyl conductive polymers have been prepared using the facile solution free radical, anionic and atom transfer radical polymerization methods. The novel polymers including the homopolymer P(ADN), two highly soluble homopolymers P(2ADN) and P(3ADQ), two series of ADN moities containing copolymer P(ADN-co-S) and P(ADN-co-VK), a series of pyrene moieties containing copolymer P(PyPA-co-VPy) and two novel amphiphilic BAB-type block copolymers, ADN-PEG3400-ADN and Py-PEG3400-Py which contain blue and greenish-blue fluorescent moieties. The chemistry and physical properties of the intermediates, the resulting polymers were characterized using nuclear magnetic resonance spectroscopy (NMR), matrix-assisted laser desorption ionization time-of-flight mass spectrum (MALDI-TOF MS), fourier-transform infrared spectroscopy (FT-IR), elemental analysis (EA), gel permeation chromatography (GPC), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), UV-Visible spectroscopy (UV-Vis), photoluminescence spectroscopy (PL), cyclic voltammetry (CV), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and fabrication of polymer light-emitting diodes (PLED) and their measurements.
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Triguero, Enguídanos Jordi. "Study of conductive polymers, biomolecules and their hybrids through computational approaches." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/666579.
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In this thesis, different theoretical approaches designed to study a wide interval of length- and/or time-scales have been used to examine the microscopic properties of chemical systems with varying degrees of complexity and size. Firstly, the conformational preferences and optical properties of a tripeptide derived from the RGD sequence, the unit of a cell adhesive activity domain in adherent proteins, have been analyzed. Calculations on this peptide, which contains an exotic amino acid bearing a 3,4-ethylenedioxythiophene (EDOT) ring as side group, have been performed using DFT and time depending DFT methods. Results indicate that the bioactive characteristics of the RGD sequence become unstable in presence of the new residue because of both the steric hindrance caused by the EDOT side group and the repulsive interactions between the oxygen atoms belonging to the backbone amide groups and the EDOT side group. This information has been used to propose some chemical changes oriented to improve the bioadhesive properties. The interaction of a cell penetrating tetrapeptide, RPAR, adsorbed onto a gold substrate and the deposition of a pre-assembled peptide-polymer conjugate, cyc[(L-Gln-D-Ala-L-Lys-D-Ala)2] coupled with two poly(n-butyl acrylate) blocks, onto a mica substrate have been examined through molecular dynamics (MD). Results indicate that RPAR binds both the (100) and (111) gold surface facets. The conformation of the adsorbed peptide differs considerably from the bioactive conformation. However, the new conformations are not stabilized by strong intramolecular interactions. Accordingly, gold nanoparticles can be considered as suitable vehicles for the transport and targeted delivery of this CendR peptide. For the pre-assembled peptide-polymer conjugate, a theoretical approach that simulates the selective and progressive desolvation of the nanotube-like assembly has been used, demonstrating that the solvent presence during deposition is the main responsible for the unexplained conformational preferences of the acrylate blocks. When the proportion of solvent drops, the loss of many attractive solute-solvent interactions induces a meaningful increase in the number of torsions. MD has been also used to understand the impact of the solvation medium and the action of a detergent in the structure of a representative outer membrane protein (OMP). Calculations show the destabilization of the protein in water, while in presence of detergent molecules in solution or the bilayer induce a partial and complete protective effect, respectively. Combining stochastic algorithms and MD simulations the atomistic details of polymer coatings deposited over metal surfaces have been modeled to reproduce the experimentally observed topographic features of poly(3,4-ethylenedioxythiophene), PEDOT, deposited onto stainless steel. Results have provided an excellent model system to test the developed modeling strategy. Multi-phasic simulations have been conducted to explain the influence of protein···polymer interactions in the antimicrobial biocapacitors activity of lysozyme (LYZ)-containing PEDOT electrodes through atomistic MD calculations. Two models have been investigated: i) a biphasic system in which the protein was adsorbed onto the surface of PEDOT, PEDOT/LYZ; and ii) a biocomposite in which the LYZ was homogeneously distributed inside the PEDOT matrix, P(EDOT-LYZ). MD simulations have been performed in absence and presence of electric fields, the latter mimicking the one originated by the voltage cell difference in biocapacitors. In PEDOT/LYZ electrodes, the loss of biological activity has been attributed to the anisotropy of the PEDOT···LYZ electrostatic interactions. In contrast, anisotropic effects are minimized in P(EDOT-LYZ), conserving activity. The bactericidal activity of PEDOT/LYZ and P(EDOT-LYZ) biocapacitors is independent of the electric field applied or supplied during charge-discharge processes.<br>En esta tesis, diferentes métodos diseñados para estudiar un amplio intervalo de tamaños y/o escalas de tiempo han sido usados para examinar las propiedades microscópicas de sistemas químicos con diferentes grados de complejidad y magnitud. Primeramente, se han analizado las preferencias conformacionales y las propiedades ópticas de un tripéptido derivado de la secuencia RGD, el dominio de actividad adhesiva en proteínas adherentes. Los cálculos de este péptido, que contiene un aminoácido exótico que porta un anillo de 3,4-etilendioxitiofeno (EDOT) como grupo lateral, han sido llevados a cabo usando métodos de DFT y DFT dependiente del tiempo. Los resultados indican que las características bioactivas de la secuencia RGD se vuelven inestables en presencia del nuevo residuo debido tanto a los impedimentos estéricos causados por el EDOT de la cadena lateral como por las interacciones repulsivas entre los átomos de oxígeno de los grupos amida que pertenecen a la cadena principal del péptido y del grupo lateral de EDOT. Esta información ha sido utilizada para proponer algunos cambios en la composición química orientados a mejorar las propiedades bioadhesivas. La interacción de un tetrapéptido permeabilizador vascular, RPAR, que ha sido adsorbido sobre un sustrato de oro y la deposición de un conjugado péptido-polímero pre-ensamblado, cyc[(L-Gln-D-Ala-L-Lys-D-Ala)2] unido a dos poli(n-butil acrilatos), sobre un sustrato de mica han sido examinados a través de dinámica molecular (MD). Los resultados indican que RPAR se une tanto a las caras (100) y (111) del oro. La conformación del péptido adsorbido difiere considerablemente de la conformación bioactiva. Aún así, las nuevas conformaciones no son estabilizadas por fuertes interacciones intramoleculares. De acuerdo a estos resultados, las nanopartículas de oro pueden ser consideradas como vehículos indicados para el transporte y liberación selectiva de este péptido CendR. Para el conjugado péptido-polímero pre-ensamblado, se ha usado un método teórico que simula la desolvatación progresiva del nanotubo, demostrando que la presencia del solvente durante la deposición es el principal responsable para las preferencias conformacionales inexplicadas de los bloques acrílicos. Cuando la proporción de solvente cae, la pérdida de muchas interacciones atractivas entre soluto y solvente induce un significante aumento en el número de torsiones. También se ha usado MD para entender el impacto del medio solvente y la acción de un detergente en la estructura de una proteína de membrana exterior (OMP) representativa. Los cálculos muestran la desestabilización de la proteína en agua, mientras que la presencia de moléculas de detergente en solución o en bicapa inducen un efecto protector parcial y completo, respectivamente. Combinando algoritmos estocásticos y simulaciones de MD, se ha modelado los detalles a nivel atómico de los recubrimientos de poli(3,4-etilendioxitiofeno), PEDOT, sobre acero inoxidable para reproducir las propiedades topográficas observadas experimentalmente. Los resultados han proporcionado un modelo excelente para probar la estrategia de modelado desarrollada. Se han realizado simulaciones multifásicas para explicar la influencia de las interacciones proteína-polímero en la actividad antimicrobiana de los condensadores que contienen electrodos lisozima (LYZ)-PEDOT, a través de cálculos de MD atomísticos. Dos modelos se han investigado: i) un sistema bifásico en los que la proteína ha sido adsorbida sobre la superficie de PEDOT, PEDOT/LYZ; y ii) un biocompuesto en el que la LYZ ha sido distribuida homogéneamente dentro la matriz de PEDOT, P(EDOT-LYZ). Las simulaciones de MD se han realizado tanto en ausencia como en presencia de campos eléctricos, el último para simular los originados por la diferencia de voltaje en los biocondensadores. La iso- y aniso-tropía de las interacciones son claves para la conservación
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Staicovici, Stefan. "Microwave welding and disassembly of thermoplastic materials using intrinsically conductive polymers /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487948807586222.
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Bereznev, Sergei. "Solar cells based on polycristalline copper-indium chalcogenides and conductive polymers /." Online version, 2003. http://bibpurl.oclc.org/web/26409.
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Ozturk, Tugba. "Conductive And Electrochromic Properties Of Poly(p-phenylene Vinylene)." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12605806/index.pdf.
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P-xylene-bis(diethylsulphonium chloride) (PXBDC) monomer was synthesized by the reaction of &<br>#945<br>,&<br>#945<br>-dichloro-p-xylene with tetrahydrothiophene or diethyl sulphide. Electrochemical behavior of this monomer (PXBDC) was examined by cyclic voltametry. Polymerization was achieved both by using electrochemical and chemical polymerization techniques. In the electrochemical technique, PPV was synthesized by constant potential electrolysis in acetonitrile-tetrabutylammonium tetrafluoroborate (TBAFB) solvent-electrolyte couple. The polymer obtained from the electrode surface was converted to the poly(p-phenylene vinylene) (PPV) by the thermal elimination reaction of diethyl sulphide and HCl. Also, PPV was doped via electrochemical doping with ClO4- dopant ion.
The chemical structures were confirmed both by Nuclear Magnetic Resonance Spectroscopy (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). The thermal behavior of chemically and electrochemically synthesized conducting polymers were investigated by Differential Scanning Calorimetry (DSC). Also, electrochromic and spectroelectrochemical properties of PPV was investigated by using UV-VIS spectrophotometer.
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Nettleton, Jason William. "SYNTHESIS, CHARACTERIZATION, AND MATERIAL PROPERTIES OF IONIC THIOL-YNE ELASTOMERS." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1596473776260031.
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Yang, Run. "A Superionic Conductive Solid Polymer Electrolyte Based Solid Sodium Metal Batteries with Stable Cycling Performance at Room Temperature." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1619741453185762.
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Garcia, Romny. "Evaluation of the Role of Hydrodynamic Shear on Breakage of Thermally Conductive Particles During Compounds Preparation." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1379692099.
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Wahlström, Niklas. "Conductive polymers as hole-conductors for solid-state dye sensitized solar cells." Thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-231937.
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Appello, Mario. "Real-time measurement of electrical properties during the processing of conductive polymers." Thesis, University of Warwick, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341559.
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Byrom, Joseph Robert. "Electrically Conductive Polymers and their Use as Novel Pigments in Advanced Coatings." Diss., North Dakota State University, 2018. https://hdl.handle.net/10365/27458.
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With the push to more environmentally friendly materials to solve some of the biggest challenges in the coatings industry, electrically conductive polymers (ECPs) are seen as a flexible solution due to their unique properties. ECPs are seen as an attractive substitute to the current metallic materials used in applications such as printable electronics, anti-static protection, and corrosion mitigation. Polypyrrole (PPy) is seen as a popular class of ECPs due to its inherent high electrical conductivity, resistance to environmental degradation, and ease of synthesis. The first part of this work was to study the ability of polypyrrole to be synthesized through a novel photochemical process. This method eliminated the need to stabilize particles in a suspension and deposit an electrically conductive film onto a variety of substrates. The second part of this work was to synthesize functional versions of PPy that could further be crosslinked into the coating matrix to improve bulk physical properties through better interaction between the functional filler and the organic coating matrix. The last part of this work is based off prior work at NDSU on AL-flake/PPy composites. This study took the development of these pigments further by incorporating organic anions known to inhibit corrosion and study their efficacy. Advanced analytical methods such as Conductive Atomic Force Microscopy was used to study the electrical properties of PPy. In addition, advanced electrochemical tests such as Electrical Impedance Spectroscopy (EIS), Scanning Vibrating Electrode Technique (SVET), Linear Polarization (LP), and Galvanic Coupling (GP) were conducted alongside traditional accelerated weathering techniques such as ASTM B117 and GM 9540 to determine the corrosion resistance of the synthesized coatings.<br>Army Research Laboratory
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Kerton, Francesca Maria. "Organometallic based transition metal catalysts." Thesis, University of Sussex, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285060.
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Peng, Fang. "Controlling Radial Compositional Gradient in Electrospun Polyacrylonitrile/Silver Composite Fibers Using Chemical Solvent Vapor Treatment and Sintering Techique." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1398363203.
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CARADONNA, ANDREA. "Carbon-based polymer nanocomposites with enhanced conductive properties." Doctoral thesis, Politecnico di Torino, 2018. http://hdl.handle.net/11583/2703852.
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Nowadays the development of new technologies requires materials with unconventional combination of properties. Polymers are classified as electrical and thermal insulating materials, which limits their use for several important technological applications. However, conductive polymers could be used in order to overcame drawbacks in the use of metals, metal alloys and ceramic materials as conductive media. Thermal conductive polymers could be profitably exploited in heat management applications (e.g. heat sink, heat exchangers), while electrical conductive polymers could be used in different fields depending on their electrical conductive values. To enhance the conductive properties of polymers, several approaches has been reported in literature. However, the most established way to achieve this goal consists in the development of suitable composite materials by means of the incorporation of conductive fillers within the polymeric matrix. The choice of the conductive filler is a crucial point in the development of the final material. Due to their extremely high thermal and electrical conductivity, coupled with the low density, the nano-metric scale and the outstanding mechanical properties, carbon-based nanomaterials are the most promising fillers suitable for processing conductive polymers. Since graphene nanoplatelets (GNPs) are considered young materials with potentials not yet fully exploited, multiwall carbon nanotubes (MWCNTs) are nowadays the most established materials used as conductive filler.
In this thesis work thermally and electrically conductive polymer composites, filled with carbon-based nanomaterials were investigated.
In the first part of the experimental work, particular attention was devoted to the development of GNPs-based thermally conductive polymers. By properly selecting several polymeric matrices and comparing several available processing techniques it was possible to outline a guideline in the use of GNPs as thermally conductive fillers. A strong filler characterization reveals that, in spite to the amount of defects and to the filler purity, the main GNPs properties able to enhance the thermal conductivity of polymers is the lateral dimension.
With the aim of developing metal-free circuits integrated in nanocomposite, a laser printing process was successfully exploited in order to obtain electrical conductive paths on the surface of a polymeric materials containing MWCNTs. Starting from the literature knowhow and new experimental results, a complete comprehension of the parameters that affect the laser printing process was achieved by applying a statistical approach. By analysing the experimental outcomes with a statistical approach, it was possible to focus the attention on the main laser parameters that govern the process, thus obtaining multifunctional and multidirectional conductive materials with surface electrical resistance per unit length (inside the tracks) lower than 1 kΩ/cm at 0.5 wt.% of MWCNTs loading content.
Finally, by combining outcomes obtained as described above, hybrid carbon-based nanocomposites were developed, with the purpose of enhancing contemporaneously thermal and electrical conductivity. Hybrid materials, obtained starting from a commercial masterbatch containing MWCNTs, demonstrated the possibility to partially replace the high amounts of carbon nanotubes with low cost carbon based materials without worsening the good conductive properties.
Not only conductive properties were investigated, but all the studied materials were also characterized by means of mechanical and thermal stability tests, thus demonstrating the possibility of adopting carbon-based polymer nanocomposites as multifunctional materials.
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Adhikari, Amit. "Polymer Matrix Composite: Thermally Conductive GreasesPreparation and Characterization." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1556282222035491.
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Taubert, Clinton J. "Low Percolation Threshold in Electrically Conductive Adhesives using Complex Dimensional Fillers." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1542727822099192.
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Zhao, Wei. "Flexible Transparent Electrically Conductive Polymer Films for Future Electronics." University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1297888558.
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Rendon, Piedrahita Camilo. "Study of highly conductive, flexible polymer electrolyte membranes and their novel flexoelectric effect." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1541440496157425.
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Yesil, Sertan. "Processing And Characterization Of Carbon Nanotube Based Conductive Polymer Composites." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611984/index.pdf.
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The aim of this study was to improve the mechanical and electrical properties of conductive polymer composites. For this purpose, different studies were performed in this dissertation. In order to investigate the effects of the carbon nanotube (CNT) surface treatment on the morphology, electrical and mechanical properties of the composites, poly(ethylene terephthalate) (PET) based conductive polymer composites were prepared by using as-received, purified and modified carbon nanotubes in a twin screw extruder.
During the purification of carbon nanotubes, surface properties of carbon nanotubes were altered by purifying them with nitric acid (HNO3), sulfuric acid (H2SO4), ammonium hydroxide (NH4OH) and hydrogen peroxide (H2O2) mixtures. Electron Spectroscopy for Chemical Analysis (ESCA) results indicated the removal of metallic catalyst residues from the structure of carbon nanotubes and increase in the oxygen content of carbon nanotube surface as a result of purification procedure. Surface structure of the purified carbon nanotubes was also modified by treatment with sodium dodecyl sulfate (SDS), poly(ethylene glycol) (PEG) and diglycidyl ether of Bisphenol A (DGEBA). Fourier Transformed Infrared Spectroscopy (FTIR) spectra of the carbon nanotube samples indicated the existence of functional groups on the surfaces of carbon nanotubes after modification. All composites prepared with purified and modified carbon nanotubes had higher electrical resistivities, tensile and impact strength values than those of the composite based on as-received carbon nanotubes, due to the functional groups formed on the surfaces of carbon nanotubes during surface treatment.
In order to investigate the effects of alternative composite preparation methods on the electrical and mechanical properties of the composites, in-situ microfiber reinforced conductive polymer composites consisting of high density polyethylene (HDPE), poly(ethylene terephthalate) and carbon nanotubes were prepared in a twin screw extruder followed by hot stretching of PET/CNT phase in HDPE matrix. Composites were produced by using as-received, purified and PEG treated carbon nanotubes. SEM micrographs of the hot stretched composites pointed out the existence of in-situ PET/CNT microfibers dispersed in HDPE matrix up to 1 wt. % carbon nanotube loadings. Electrical conductivity values of the microfibrillar composites were higher than that of the composites prepared without microfiber reinforcement due to the presence of continuous PET/CNT microfibers with high electrical conductivity in the structure.
To investigate the potential application of conductive polymer composites, the effects of surfactant usage and carbon nanotube surface modification<br>on the damage sensing capability of the epoxy/carbon nanotube/glass fiber composite panels during mechanical loadings were studied. Surface modification of the carbon nanotubes was performed by using hexamethylene diamine (HMDA). 4-octylphenol polyethoxylate (nonionic) (Triton X-100) and cetyl pyridinium chloride (cationic) (CPC) were used as surfactants during composite preparation. Electrical resistivity measurements which were performed during the impact, tensile and fatigue tests of the composite panels showed the changes in damage sensing capabilities of the composites. Surface treatment of carbon nanotubes and the use of surfactants decreased the carbon nanotube particle size and improved the dispersion in the composites which increased the damage sensitivity of the panels.
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De, Puran K. "Stable Hetero-Acene Analogs of Heptacene: The Synthesis and Study of their Conductive Properties in Organic Transistors And The Photo-induced Formation of Quantum Dot – Conductive Polymers (QD:CP) for Application in Photovoltaics." Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1319201004.
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Cruz-Estrada, Ricardo Herbe. "In-situ production of electrically conductive polyaniline fibres from polymer blends." Thesis, Brunel University, 2002. http://bura.brunel.ac.uk/handle/2438/2406.
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Polymers and polymer-based composite materials with electro-conductive properties, respectively, are materials with several potential applications. New materials are being offered in every area and novel products are constantly being introduced. Among these new materials, composites made of electro-conductive monofilaments and insulating polymers are nowadays being used as antistatic materials in the carpets and textiles industries. One promising approach for the manufacture of this kind of material is to generate the electrically conductive fibres in-situ, that is, during the actual forming process of the component. The main objective of this project was to establish the feasibility of producing electrically conductive polyaniline (PANI) fibres within a suitable polymer matrix by means of the development of a suitable processing strategy, which allows the fabrication of an anisotropically conducting composite. It is remarkable, however, that layered structures of the conducting filler were also formed within the matrix material. The latter morphology, particularly observed in compression moulded specimens of a specific polymer system, was also in good agreement with that inferred by means of a mathematical model. Experimentation was carried out with three different PANI conductive complexes (PANIPOLTM). They were initially characterised, which assisted in the identification of the most suitable material to be deformed into fibres. Preliminary processing was carried out with the selected PANIPOLTM complex, which was blended with polystyrene-polybutadiene-polystyrene (SBS), low density polyethylene (LDPE) and polypropylene (PP), respectively. The resultant blends were formed by ram extrusion, using a capillary die, to induce the deformation of the conducting phase into fibres. The morphological analysis performed on the extrudates suggested that the most suitable polymer matrix was SBS. Further experimentation was carried out with the polymer system selected. The relationships between the content of conductive complex in the composites and their electrical conductivity and microstructure were established. The blends were compression moulded and they displayed a morphology of layered domains of the conducting phase within the SBS matrix. The behaviour of the conductivity with respect to the PANIPOLTM complex in the compression moulded blends was found to be characteristic of a percolating system with a threshold as low as 5 weight percent of the conducting filler in the blends. The morphological analysis performed on the extruded blends suggested that the conducting phase was deformed into elongated domains, aligned parallel to the extrusion direction, which in some cases displayed a considerable degree of continuity and uniformity. The level of electrical conductivity in the extrudates was considerably lower than that of their corresponding non-extruded blends. This was attributed to a lack of continuity in the conducting elongated domains produced in-situ within the SBS matrix. Percolation theory and a generalisation of effective media theories were used to model the behaviour of the conductivity with respect to the content of PANIPOLTM in the compression moulded blends. Both approaches yielded similar values for the critical parameters, which were also in good agreement with the percolation threshold experimentally observed. The results of the modelling suggested that, at the percolation threshold, the morphology of the composite may consists of aggregates of flattened polyaniline particles forming very long layered structures within the SBS matrix, which is in agreement with the results of the morphological analysis.
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Kanbur, Yasin. "Conductive Polymer Nanocomposites Of Polypropylene And Organic Field Effect Transistors With Polyethylene Gate Dielectric." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613312/index.pdf.
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One of the aim of this study is to prepare conductive polymer nanocomposites of polypropylene to obtain better mechanical and electrical properties. Composite materials based on conductive fillers dispersed within insulating thermoplastic matrices have wide range of application. For this purpose, conductive polymer nanocomposites of polypropylene with nano dimentional conductive fillers like carbon black, carbon nanotube and fullerene were prepared. Their mechanical, electrical and thermal properties were investigated.
Polypropylene (PP)/carbon black (CB) composites at different compositions were prepared via melt blending of PP with CB. The effect of CB content on mechanical and electrical properties was studied. Test samples were prepared by injection molding and compression molding techniques. Also, the effect of processing type on mechanical and electrical properties was investigated. Composites become semiconductive with the addition of 2 wt% CB.
Polypropylene (PP) / Carbon Nanotube (CNT) and Polypropylene / Fullerene composites were prepared by melt mixing. CNT&rsquo<br>s and fullerenes were surface functionalized with HNO3 : H2SO4 before composite preparation. The CNT and fullerene content in the composites were varied as 0.5, 1.0, 2.0 and 3.0 % by weight. For the composites which contain surface modified CNT and fullerene four different compatibilizers were used. These were selected as TritonX-100, Poly(ethylene-block-polyethylene glycol), Maleic anhydride grafted Polypropylene and Cetramium Bromide. The effect of surface functionalization and different compatibilizer on mechanical, thermal and electrical properties were investigated. Best value of these properties were observed for the composites which were prepared with maleic anhydride grafted polypropylene and cetramium bromide.
Another aim of this study is to built and characterize transistors which have polyethylene as dielectric layers. While doing this, polyethylene layer was deposited on gate electrode using vacuum evaporation system. Fullerene , Pentacene ve Indigo were used as semiconductor layer. Transistors work with low voltage and high on/off ratio were built with Aluminum oxide - PE and PE dielectrics.
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Lang, Udo. "Experimental methods for evaluating the mechanical properties of thin layers of intrinsically conductive polymers." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17754.
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Reuven, Darkeyah Godel. "Synthesis and characterization of dinitrophenyl of dinitrophenyl functionalized conductive polymers capable of biospecific binding." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2009. http://digitalcommons.auctr.edu/dissertations/74.
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A series of DNP (2,4-dinitrophenyl)functionalized polypyrrole polymers that are specific to antibodies and immune receptors on cell have been synthesized and characterized (See Figure). This is a terpolymer composed of three monomers; monomer 1 (M1, pyrrole), macromonomer 2 (M2, pyrrole with pendant ethylene glycol) and macromonomer 3 (M3, pyrrole with pendant DNP). These polymers are expected to be useful for controlling receptor binding and cell activation, and with eventual application in biosensors. Conductivity measurement indicate that the terpolymers are conductive, without adding external doping agents conductivity values of 5 x 1 06 S cm ‘(at 25 °C) were obtained. Binding studies with anti-DNP IgE studies are promising, fraction of binding sites occupied vs. concentration indicates specific and efficient binding at nanomolar concentration. Therefore, DNP functionalized polypyrrole are excellent materials for preparing nanowires in biosensors for detecting biomarkers. We have also determined that these polymers are biocompatible. Nanowires are currently being fabricated using the functionalized conductive polymers. In addition to synthesis and characterization, the thermal properties of the functional polymers will be discussed with regards to the fabrication of nanowires for biosensing applications.