In 2006, consulting services and a University Nano Technology Research Lab, were utilized to carry out characterization studies of Graphonyx™ CNOs. Avenues for functionalization and product utilization were also pursued.
The following information is a summary of the first annual progress report received in 2007:
ABSTRACT: Graphitic Nano Onions LLC (GNO) has a process to produce Carbon Nano Onions in Chains (CNOC) that have a unique morphology. GNO sponsored an experimental study using the CNOC material to develop multifunctional polymer nanocomposite materials, especially electrically conductive polymers. Current experimentation demonstrated dramatically improved electrical conductivity after functionalization of the CNOC. The treatment was directed by GNO and the material was given to us for testing. This study demonstrated that new grades of CNOC with superior quality in terms of electrical conductivity and graphitic structure were developed. The material characterization results obtained in the study are discussed in detail in this report. The study also involved material processing and evaluation of the mechanical properties and electrical conductivity of nanocomposite materials produced by incorporating CNOC into different host materials including epoxy, polyurethane, and in continuing work in cement.
Our report on this activity is brief since the analytical service provided to GNO became routine for both the GNO team and the University team. The GNO experts used the analytical data to adjust the synthesis of CNOC and to improve the manufacturing process. This University team has performed more than 250 analyses of CNOC material by using sophisticated techniques such as:
Environmental Scanning Electron Microscopy (ESEM),
High Resolution Transmission Electron Microscopy (HRTEM),
X-Ray Diffraction (XRD),
Thermal Gravimetric Analysis (TGA),
Electrical Conductivity Measurements,
GNOC material is a novel carbon nanostructured material that has a unique spherical morphology. The CNOC material is catalyst free, lightweight and has hydrophobic nanoparticles. Compressed CNOC powder has high electrical conductivity. Therefore, a composite was formed according to the following procedures: (i) solution casting a CNOC film or other nanoparticles in a mold; (ii) coating the film with epoxy or polyurethane; and (iii) pressure casting in a mold. The composite material formed has good electrical and thermal conduction, piezoresistive and possibly piezomagnetic properties, and possibly power harvesting properties when a plasma gas or electrolyte is passed over it. An interesting property of the material formed in this way is that it is electrically conductive on one side and electrically insulating on the other side.
Having nanoscale size effects, CNOC can be combined in host materials to produce changes in the electronic, photonic, catalytic, or other properties of the bulk material for use in virtually all types of structural and composites applications. CNOC are expected to have high strength as well as high thermal and electrical conductivities and therefore can provide structural and functional capabilities simultaneously, thus forming a smart material. For applications at the macro scale, CNOC smart composite materials can be used for sensors due to their change of electrical conductivity under mechanical deformation. This material can measure strain and it can also detect cracks. A CNOC polymer based piezoresistive strain sensor can be developed for structural health monitoring (SHM) applications using a spray-on technique or by dispersing powder CNOC in a polymer. Functional fabrics and yarns have been developed by spinning CNOC into thread and weaving the thread. A nanomaterial based sensor can be light and flexible and easily embedded into a structure. These characteristics are suitable for developing new sensors required for health monitoring of lightweight structures. In the area of civil engineering, significant investigation is underway to determine if nanoparticles added to cement can act as bridges across cracks and voids to transfer load and create a material more impervious to bending tensile loading. Nanoparticles have a high strain to failure which helps in the load transfer across cracks. There is potential to develop nanoscale hybrid materials that have designed-in properties to meet specific applications. CNO chains are carbon onions linked together and have the advantages of being catalyst free, and highly electrically conductive.
Studies of resistivity versus compressive stress for a 10% wt. CNOC/epoxy nanocomposite have been quite revealing. In general, nano-enhanced polymer design can provide electrical conductivity to the polymer using carbon nano onion chains and can reinforce epoxy and other matrix materials. The CNOC when compacted are highly electrically conductive and presently about 5-10% by weight of CNOC can be added to the epoxy to provide electrical conductivity. A limiting factor is the viscosity when it is too high for wetting micro fibers when making a laminated composite. The next step in the nanocomposite development is plasma etching to provide better dispersion and adhesion to the matrix. The plasma treatment will be controlled so that the electrical properties of the CNOC are not significantly affected. In general, a goal is sought to provide multi functionality to the material as in achieving the following: (i) having the greatest electrical conductivity possible, (ii) self-sensing to detect cracks, corrosion, and delamination in composites, and (iii) to do this without reducing the other properties of the matrix material.
CNOC must be spun into thread to provide a strong bulk material. The thread can be made completely of CNOC or it can be blended using two or more materials. The goal is to provide a strong thread with smart material properties that cannot be achieved by any other material system on earth. Multiple threads will be woven together to form a fiber. A major advantage of polymers based on CNOC nanomaterials is that the polymer or thread can be used in composite materials to form self-sensing materials. Engineering asset evaluation and condition monitoring using CNSC nanomaterials may have hundreds of applications in components where smart nanocomposites can be used for multifunctional properties improvement, self-sensing of damage, and possibly limited self-repair of the material. CNOC materials have been shown in the lab to have new properties and potential for improving structural performance along with self-test and monitoring composite conditions.
Given its unique morphology and structure, Graphyonyx is an excellent candidate for a number of applications.
- Energy generation or storage
- Advanced composites
- Photovoltaic fuel cell applications
- Multi-functional active surfaces
- Hydrophobic coatings (airframes, marine surfaces)
- Composites for protective armor
- Electrostatic shielding
- Radar absorption
- Solar panel surfaces
- High temp heat sinks forLED lights
- Next generation strong/light polymers for 3D printing
- MRI/radiology diagnostics
- Industrial lubricants
- Super capacitor/batteries for electrical storage
- Water filtration including fracking water from gas production
- Electrical and thermal conductivity and water/ice mitigation coatings
- Biomedical Areas:
- Scaffolding for human bone and cartilage regrowth
- Biocompatible polymer composites, for thermal cancer cell destruction
- As toxin scavenger
- Molecular beacons and pharmaceutical delivery platforms