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          Your global supplier for materials

          Plasma functionalised Graphene Nanoplatelets

           

          Graphene is a carbon based material which is inherently inert and which does not like to mix with, or bond to, other materials. Its excellent properties can only be fully realised when this fundamental hurdle is overcome, and it can be properly dispersed and covalently bonded into matrices such as epoxy resins.

          • Disc 1 is a pure epoxy disc
          • Disc 2 is an epoxy disc with 0.5% non-functionalised carbon nanomaterials added. This clearly shows agglomeration, poor dispersion and thus will have no improvements in its thermal or electrical conductivity, stiffness or strength.
          • Disc 3 is an epoxy disc with exactly the same amount of carbon nanomaterials added (0.5 wt.%), however this time they have been functionalised using plasma. The material is homogeneous with well dispersed carbon nanomaterial, and will have improved thermal and electrical conductivity, stiffness and strength.

          Goodfellow is offering plasma functionalised Graphene Nanoplatelets from Haydale. Plasma functionalisation differs from the more common acid treatment methods, as it is a low temperature, low energy, dry process, with no effluent disposal, and unlike acid processing it has been shown to be benign to the structure of the raw material.

          Product Name HDPlas® GNP
          Synonyms Graphene Nanoplatelets, GNP, Graphene, Graphite
          Chemical Family Carbon allotrope; plasma functionalised graphene and graphitic nanoplatelets
          Properties High mechanical strength; high electrical conductivity; high thermal conductivity; high surface area
          Product Uses Mechanical, electrical and thermal enhancements

          About HDPlas® GNP

          • Plasma processed graphitic nanomaterials
          • Plasma treatment exfoliates graphene sheets
          • Chemical functionalisation facilitates nanomaterial dispersion for enhanced applicational properties
          • Haydale’s plasma process is suitable for a broad range of commercially available nanomaterials
          • An accredited and cost efficient solution that maintains integrity of platelets
          • Both research and industrial quantities available

          Typical Data

          Data Measurement Method
          Bulk Density ~0.215 g/cm3 EN ISO 60
          Amorphous Carbon Not Detected SEM/TEM
          Specific Surface Area ~20 m2/g BET Analysis
          GNP Planar Size 0.3 - 5 µm SEM
          GNP Thickness <50 nm SEM
          Graphene Layers 10 to 100 -
          Source Natural graphite -
          Form supplied Dry powder -

          Individual data available on request.

          Please download a datasheet on graphene here.

          Electron Microscopy

          Typical micrograph for all HDPlas® GNP products

          The Manufacturing Process

          The manufacturing of Haydale plasma functionalised graphene takes place in a low-pressure vessel – a rotating drum, with a central electrode that generates the plasma. The process functionalises the material in a benign, environmentally friendly way at low temperature. This is different to acid processing as it is a dry functionalisation treatment – the material goes in and comes out completely dry with no hazardous waste stream and with less damage to the surface of the graphene.

          The oxygen functionalisation process attaches functional groups to the surface, giving increased dispersion and compatibility in a selection of solvents and polymers. This functionalisation overcomes graphene’s inert nature and gives improved bonding with the bulk material.

          The degree to which the surface of the material is functionalised also has an impact on how well the nanoplatelets will mix with the bulk material. To help our customers identify the most appropriate functionalisation level for their product and process, Goodfellow is offering a kit containing high, medium and low functionalisations. After initial results, it is possible to further control the functionalisation level, and therefore we can offer a custom product to suit your application.

          Other Functionalisations

          There are also other functionalities available that will give the graphene different properties. The current standard products are displayed below. However Haydale’s patent applied for plasma process is flexible and other options are available. Haydale’s plasma process can also functionalise a wide range of other carbon-based nanomaterials. Please contact us for more information on the availability of different functionalisations.

          Standard Products Process Route Note
          HDPlas® GNP - O2 Oxygen In stock
          HDPlas® GNP - N2 Nitrogen In stock
          HDPlas® GNP - NH3 Ammonia In stock
          HDPlas® GNP – F Fluorocarbon In stock
          HDPlas® GNP – Ar Argon In stock
          HDPlas® GNP – COOH Acid vapour In stock

          Please download a datasheet on graphene here.

          References

          Haydale HDPlas® GNP have been independently tested and accredited by the National Physical Laboratory in the United Kingdom as being functionalised.

          Haydale HDPlas® GNP has been independently tested by the not-for-profit Aerospace Corporation in the USA as having the ability to double the strength of epoxy composites. A link to their published findings can be found here.

          HDPlas® is a registered trademark of Haydale Limited

          Publications

          We are pleased to provide a list of scientific papers showcasing the latest research using functionalised graphene nanoplatelets as manufactured by Haydale, and now available through Goodfellow.

          Decoration of Carbon Nanostructures with Metal Sulphides by Sonolysis of Single-Molecule Precursors

          Authors
          Ana C. Estradaa, Ernest Mendozab and Tito Trindadea
          a Aveiro Institute of Nanotechnology, University of Aveiro,
          b Centre de Recerca en Nanoenginyeria, Universitat Politècnica de Catalunya

          Journal
          Eur. J. Inorg. Chem., 2014 3184–3190
          DOI: 10.1002/ejic.201402056

          Abstract
          Carbon nanostructures have emerged in recent decades as uniquely convenient materials for a number of technologies. Some of their envisaged applications require hybrid nanostructures that result from the coupling of semiconducting phases to the carbon materials. Here, we describe a new sonochemical method to decorate carbon-based materials (multiwalled carbon nanotubes, graphene oxide, and graphite flakes) with metal sulfide nanophases. In this research, we have used a CdII alkyldithiocarbamate complex as a single source to produce CdS nanophases that nucleate and grow over the carbon substrates. However, other metal sulfides can be produced by a similar methodology, which paves the way to a scalable method for the preparation of hybrid metal sulfide/carbon nanomaterials.

          http://dx.doi.org/10.1002/ejic.201402056

          Investigation of Thermal Properties of SiC Ceramics Containing Carbon Nanostructures by Photothermal Measurements

          Authors
          Anna Kazmierczak-Balata a, Jacek Mazur b, Jerzy Bodzenta a, Dominika Trefon-Radziejewska a, Lukasz Drewniak a
          a Institute of Physics-CND, Silesian University of Technology, Gliwice, Poland
          b Institute of Non Ferrous Metals, Gliwice, Poland

          Journal
          Int J Thermophys 2014?
          DOI: 10.1007/s10765-014-1574-8

          Abstract
          This work presents an analysis of the influence of graphene reinforcement on properties of silicon carbide composites. Samples were prepared by a spark plasma sintering method. The density and hardness were obtained in the preliminary experiments. The thermal diffusivity was determined by the continuous wave photothermal technique with detection based on infrared radiometry. The thermal diffusivity is in the range of (0.48 to 0.57) cm2⋅s−1 for samples prepared from granulated SiC and in the range of (0.56 to 0.71) cm2⋅s−1 for samples prepared from SiC powder. Thermal properties are correlated with the density of SiC ceramics. The thermal diffusivity of samples with a higher density is lower in comparison to samples with a lower density.

          http://dx.doi.org/10.1007/s10765-014-1574-8

          Effects of plasma modified carbon nanotube interlaminar coating on crack propagation in glass epoxy composites

          Authors
          John Williams a, Neil Graddage b, Sameer Rahatekar a
          a ACCIS, Dept. Aerospace Engineering, University of Bristol
          b Welsh Centre for Printing and Coating, Swansea University

          Journal
          Composites: Part A, 2013, 54, 173–181
          DOI: 10.1016/j.compositesa.2013.07.018

          Abstract
          Fibre reinforced pre-preg systems have very good in plane properties, however they are weak in their through thickness (z) direction. This research aims to address this issue by adding plasma treated carbon nanotubes (CNTs) between the prepreg plies using a simple drawdown coating procedure. The significant test result shows by coating carbon nanotubes with a relatively low areal density (1.2 g/m2) the propagation mode I toughness can be improved by up to 46%. Crack deviation leading to increased glass fibre bridging was observed for lower CNT coating concentrations explaining the improved performance. However at the highest areal coating density (2.0 g/m2) fibre bridging disappeared and a stick–slip crack response was observed resulting in lower delamination resistance. This research demonstrates a simple method to incorporate a nanointerlayer that can manipulate crack propagation, leading to increased delamination resistance.

          http://dx.doi.org/10.1016/j.compositesa.2013.07.018

          Plasma treatment as a method for functionalising and improving dispersion of carbon nanotubes in epoxy resins

          Authors
          J. Williams a, W. Broughton b, T. Koukoulas b, S. S. Rahatekar a
          a ACCIS, Department of Aerospace Engineering, University of Bristol,
          b Materials Division, National Physical Laboratory

          Journal
          Journal of Materials Science, 48, (3), 1005-1013
          DOI: 10.1007/s10853-012-6830-3

          Abstract
          This study reports on the results of plasma-treated carbon nanotubes (CNTs) in the presence of oxygen and ammonia which can be scaled up for relatively large quantities of nanomaterials. The plasma treatment has been shown to change the surface chemistry and energy as well as the morphology of the carbon nanotubes. X-ray photoelectron spectroscopy analysis shows increases in oxygen and nitrogen groups on the oxygen- and ammonia-treated CNTs, respectively. Titration of the enhanced oxygen plasma-treated CNTs reveals an increased presence of carboxylic acid groups at 2.97 wt% whilst bulk density decreases from 151 kg/m3 for untreated carbon nanotubes to 76 kg/m3 after the enhanced oxygen treatment. The free surface energy has also been shown to increase from 33.70 up to 53.72 mJ/m2 determined using a capillary rise technique. The plasma-treated carbon nanotubes have been mixed in epoxy and have shown an improvement in dispersion, which was quantitatively evaluated using an optical coherence tomography (OCT) technique shown to be suitable for nanocomposite characterisation. This research has demonstrated that it is possible to surface functionalise large quantities of carbon nanotubes in a single process, and that this process improves the dispersion of the carbon nanotubes in epoxy.

          http://dx.doi.org/10.1007/s10853-012-6830-3

          Flexographic printing of graphene nanoplatelet ink to replace platinum as counter electrode catalyst in flexible dye sensitised solar cell

          Authors
          J. Baker a, D. Deganello a, D. T. Gethin a, T. M. Watson a
          a Welsh Centre for Printing and Coating, Swansea University, Swansea, UK
          b SPECIFIC, Swansea University, Baglan Bay Innovation Centre, Baglan, UK

          Journal
          Energy Materials, 2014, 9, (1), 86-90
          DOI: 10.1179/1433075X14Y.0000000203

          Abstract
          A semitransparent catalytically active graphene nanoplatelet (GNP) ink was developed suitable for roll to roll printing onto a flexible indium tin oxide substrate at a speed of 0?4 m s21. Dye sensitised solar cells using this ink as a catalyst demonstrated efficiencies of 2.0%, compared with 2.6% for sputtered platinum. Given further optimisation, GNP inks have the potential to replace chemically reduced or sputtered platinum. This would have the benefit of replacing the chemical reduction or sputtering operations as well as providing potential material cost benefits.

          http://dx.doi.org/10.1179/1433075X14Y.0000000203

          Improvement of interfacial bonding in carbon nanotube reinforced Fe–50Co composites by Ni–P coating: Effect on magnetic and mechanical properties

          Authors
          Mahesh Kumar Mani a, Giuseppe Viola b c, Mike J. Reece b c, Jeremy P. Hal a, Sam L. Evans d
          a Wolfson Centre for Magnetics, Cardiff School of Engineering, Cardiff University, UK
          b School of Engineering and Materials Science, Queen Mary University of London, UK
          c Nanoforce Technology Limited, London, UK
          d Institute of Mechanical and Manufacturing Engineering, Cardiff University, UK

          Journal
          Materials Science and Engineering: B 2014, 188, 94–101
          DOI: 10.1016/j.mseb.2014.06.009

          Abstract
          Fe–50Co matrix composites containing 1.5 and 3 vol% of electroless Ni–P plated carbon nanotubes (CNTs) were densified using spark plasma sintering. The powder mixtures for the composites were prepared by two different routes: (a) ultrasonication only; and (b) ultrasonication followed by dry ball milling. Drying of the Ni–P plated CNTs under atmospheric conditions in the presence of ethanol promoted the nucleation and growth of graphene oxide on the coating. The ball milling route was found to be the most efficient method to disperse the coated nanotubes uniformly in the matrix. The addition of coated CNTs, which formed Taenite phase with the matrix alloy, made the composites to exhibit: (a) higher ductility, higher flexural strength, lower coercivity (Hc) and lower saturation induction (Bsat) compared to the monolithic material; and (b) higher ductility, higher flexural strength, higher Hc and lower Bsat in relation to the material with similar amount of bare CNTs.

          http://dx.doi.org/10.1016/j.mseb.2014.06.009

          Strength improvements in toughened epoxy composites using surface treated GnPs

          Authors
          Rafael J. Zaldivar a, Paul M. Adams, Hyun I. Kim, James P. Nokes and Dhruv N. Patel
          a Materials Science Department, The Aerospace Corporation, El Segundo, California

          Journal
          Journal of Applied Polymer Science, 2014, 131, (18)
          DOI: 10.1002/app.40802

          Abstract
          Nanographitic materials are gaining enormous interest as a new class of reinforcement for nanocomposites, promising revolutionary electrical, thermal, and mechanical properties. However, the progress has been quite limited especially in terms of mechanical properties. Here we report a significant leap, >2× increases in tensile strength and modulus of an epoxy composite using surface treated graphite nanoplatelets (GnPs). This corroborated by increases in Tgs as well as the presence of oxygen-functionalized groups verified by XPS, suggest improved distribution and chemical interaction at the filler-to-matrix interface. Toughness values also showed increases with concentration, without compromising the strength or failure strain. However, if solvent levels during degassing were not reduced sufficiently, negligible contributions to strength and stiffness were observed with GnP loading. Subsequent elevated temperature treatments increased the strength of the composite due to cure enhancement of the matrix material, yet did not provide mechanical enhancements due to the incorporation of the filler.

          http://dx.doi.org/10.1002/app.40802

          Synthesis and characterisation of bi-functionalised graphene and expanded graphite using n-butyl lithium and their use for efficient water soluble dye adsorption

          Authors
          Titash Mondal a, Anil K. Bhowmick a and Ramanan Krishnamoorti b
          a Department of Chemistry, Indian Institute of Technology, Patna, India
          b Department of Chemical and Biomolecular Engineering, University of Houston, USA

          Journal
          Journal of Materials Chemistry A, 2013, 1, (28), 8144-8153
          DOI: 10.1039/C3TA11212H

          Abstract
          Two effects of an organolithium reagent (n-butyl lithium) on graphene and expanded graphite are reported. Its ability to simultaneously scavenge protons and act as a nucleophile leads to a bi-functionalized graphitic system. Subsequent treatment with carbon dioxide gas generates carboxylic functionality at the proton abstraction sites. This technique promises a greenermethod for single pot carboxylation for graphitic materials. The nucleophilicity of n-butyl lithiumleads to efficient grafting of butyl groups. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and thermogravimetric analysis are used to prove the success of the reaction. Raman spectroscopy reveals more defect sites for expanded graphite compared to graphene, which leads to a higher degree of functionalization. Atomic force microscopyshows that the functional groups generated are nano-spike-shaped pendant structures attached to the graphene. These functionalized materials are used as adsorbers for efficient and fast removal of water-soluble dyes by non-covalent interaction between the dye and the carboxylic groups of the graphitic system. Spectrometric as well as kinetic studies are reported for crystal violet lactone dye adsorption. Both the modified materials show twice the adsorption capacity of the pristine materials. Superior dye adsorption properties were observed for the modified materials compared to graphene oxide.

          http://dx.doi.org/10.1039/C3TA11212H

          Lateral Diffusion of Dispersing Molecules on Nanotubes As Probed by NMR

          Authors
          Ricardo M. F. Fernandes a b, Matat Buzaglo c, Michael Shtein c, Ilan Pri Bar c, Oren Regev c, Eduardo F. Marques a, and István Furó b
          a Centro de Investigação em Química, University of Porto, Portugal
          b Division of Applied Physical Chemistry, KTH Royal Institute of Technology, Sweden
          c Ben-Gurion University of the Negev, Israel

          Journal
          J. Phys. Chem. C, 2014, 118, (1), 582–589
          DOI: 10.1021/jp4114046

          Abstract
          Noncovalent dispersion of carbon nanotubes is essential to most applications but still poorly understood at the molecular level. The interaction of the dispersing molecule with the nanotube, wrapping or nonwrapping, still awaits consensus. Herein, we have studied by 1H NMR diffusometry some features of molecular dynamics in the system of carbon nanotubes dispersed by triblock copolymer Pluronics F127 in water. The diffusional decays obtained at different diffusion times, Δ, are not single-exponential and have a complex Δ-dependent profile, ultimately implying that the polymer is observed in two states: free (in unimeric form) and nanotube-bound. Fitting a two-site exchange model to the data indicates that at any instant, only a small fraction of polymers are adsorbed on the nanotubes, with polydisperse residence times in the range of 100–400 ms. Most significantly, we further provide an estimate of D = (3–8) × 10–12 m2 s–1 for the coefficient of lateral diffusion of the polymer along the nanotube surface, which is an order of magnitude slower than the corresponding self-diffusion coefficient in water. The emerging picture is that of a nonwrapping mode for the polymer–nanotube interaction.

          http://dx.doi.org/10.1021/jp4114046

          Chlorophenyl pendant decorated graphene sheet as a potential antimicrobial agent: synthesis and characterisation

          Authors
          Titash Mondal a, Anil K. Bhowmick a and Ramanan Krishnamoorti b
          a Department of Chemistry, Indian Institute of Technology Patna, India
          b Department of Chemical and Biomolecular Engineering, University of Houston, USA

          Journal
          J. Mater. Chem., 2012, 22, 22481-22487
          DOI: 10.1039/C2JM33398H

          Abstract
          Facile synthesis of a chlorophenyl decorated graphene (CBG) sheet synthesized by a solventfree green diazotization technique is reported here. The functionalization of the material was supported by various characterization techniques including Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR) and thermal analysis. About 15 percent grafting, as determined by XPS and IR spectroscopy, could be achieved under the conditions employed. The CBG sheet was applied for the first time as a potential antibacterial agent on Gram negative bacteria Escherichia coli and Gram positive bacteria Staphylococcus aureus. The antibacterial character was quantified using the MacFarland number technique whereby the volumetric number density of colony forming units was determined. It was also quantified by a Kirby–Bauer test, where the zone formed due to mortality of bacteria caused by chlorine groups attached to the graphene was estimated by a mathematical model. Based on the zone of inhibition created, CBG was found to be more than twice as effective as unmodifiedgraphene and graphene oxide. The synthesis promises to open up a new avenue for the development of chemically converted graphene based antimicrobial agents.

          http://dx.doi.org/10.1039/C2JM33398H

          Nano-reinforcement of Resin Infused Carbon Fibre Laminates using Carbon Nano-tubes and Graphene

          Authors
          M.J. Eaton, W. Ayre, M. Williams, R. Pullin and S.L. Evans

          Journal
          16th International Conference on Experimental Mechanics

          Abstract
          The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) for the Clean Sky Joint Technology Initiative under grant agreement n° JTI-CS-2011-2-GRA-01-038. The project aims to develop nano-particle reinforced carbon fibre epoxy composites, manufactured by resin infusion (RI), for improved compression after impact (CAI) performance; thus facilitating lighter weight structures with lower manufacturing costs.

          http://www.icem16.org/resumes/r_3YI8K54D.pdf

          Datasheet

          Please download a datasheet on graphene here.

          狠狠色综合色综合网站

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