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Materials CNT. History. 1991 Discovery of multi-wall carbon nanotubes 1992 Conductivity of carbon nanotubes 1993 Structural rigidity of carbon nanotubes 1993 Synthesis of single-wall nanotubes 1995 Nanotubes as field emitters 1996 Ropes of single-wall nanotubes
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History • 1991 Discovery of multi-wall carbon nanotubes • 1992 Conductivity of carbon nanotubes • 1993 Structural rigidity of carbon nanotubes • 1993 Synthesis of single-wall nanotubes • 1995 Nanotubes as field emitters • 1996 Ropes of single-wall nanotubes • 1997 Quantum conductance of carbon nanotubes • 1997 Hydrogen storage in nanotubes • 1998 Chemical Vapor Deposition synthesis of aligned nanotube films • 1998 Synthesis of nanotube peapods • 2000 Thermal conductivity of nanotubes • 2000 Macroscopically aligned nanotubes • 2001 Integration of carbon nanotubes for logic circuits • 2001 Intrinsic superconductivity of carbon nanotubes
Potential Applications • Tips for Atomic Force Microscopy • Cells for hydrogen storage • Nanotransistors • Electrodes for electromechemical applications • Sensors of biological molecules • Catalysts • Reinforcement of composite materials • Semiconductor or metallic conductive nanomaterials • Various aerospace applications
Potential Applications • Reinforcement within a polymeric matrix • Outstanding mechanical properties • High Young’s modulus • Stiffness and flexibility • Unique electronic properties • High thermal stability • The nearly perfect structure of CNTs, their small diameter, and their high surface area and high aspect ratio, provide an amazing inorganic structure with unique properties extremely attractive to reinforcing organic polymers
Potential Applications • Flat Panel Displays • Prototypes have been made by Samsung • Gas-Discharge Tubes in Telecom Networks • Energy Storage • Electrochemical Intercalation of Carbon Nanotubes with Lithium • CNTs can be used as the cathode to make a battery hold 3x as much charge and output 10x as much power • Nanoprobes and Sensors
Potential Applications • Use as coatings • Antistatic coatings • Flame barrier coatings • Fouling release coatings • On boats to prevent marine life from adhering to the ship’s bottom
Potential Applications BMC bicycle frame made of nanotube-reinforced resin,2005 Tour de France. ARKEMA belongs to the network of partners.
Properties • When small quantities of nanotubes are incorporated into the polymer, the electrical, optical and mechanical properties improve significantly • CNTs in large amounts form clusters, diminishing their interaction • The Young’s modulus of the multi-walled carbon nanotubes is 0⋅9 TPa
Properties • Electrical conductivity:Carbon nanotubes are conductors or semiconductors, based on coiling helicity. Their conductivity ranges from 1 S/cm to 100 S/cm. This property has been calculated and verified in experiments. • Thermal conductivity: Carbon nanotubes feature thermal conductivity close to that of diamond (3000 J/K), the best thermal conductor known. • Mechanical performance:In the hexagon plane, the Young’s modulus for carbon nanotubes has been theoretically evaluated at 1TPa. Together with this outstanding strength, carbon nanotubes boast high flexibility and good plasticity. • Adsorption:Nanotubes were first studied with the objective of becoming a means of storing hydrogen for the new fuel cells. Although this application has been gradually discarded, the fact remains that nanotubes have an empty space around the cylinder axis which can constitute a nanotank. The specific surface of nanotubes is approximately 250 m2/g, imparting good adsorption capacity.
Properties • CNTs have been shown to possess many extraordinary properties such as strength 16X that of stainless steel and with a thermal conductivity five times that of copper. • aspect ratio (length over diameter) ranges from 1,000 to 1,000,000 • Electrical Resistivity: 10 -4 Ω-cm • Current Density: 107 amps/cm2 • Thermal Conductivity: 3,000 W/mK • Tensile Strength: 30 GPa • Elasticity: 1.28 TPa
Properties • Nanotube Research Articles\Overall\nanotube composites.pdf • Very good article explaining the basics of CNT’s
Additives • Additives can aid in the dispersion of the CNTs
Functionalized CNTs • Oxidation on the surfaces of these materials are useful moieties in order to bond new reactive chains that improve solubility, processability and compatibility with other materials and, therefore, improve the interfacial interactions of CNs with other substances • The most important impact has been produced by oxidation methods which, in addition to reducing impurities, cause chemical modifications of CNTs • The COOH groups generated in the oxidation process are used to attach different molecules useful to improve surface compatibility of CNTs with other materials
Functionalized CNTs • The COOH groups generated in the oxidation process are used to attach different molecules useful to improve surface compatibility of CNTs with other materials • Chemical functionalization has reached an important position in the CNT field, as different chemical processes have been developed to diversify CNT properties • The remarkable properties obtained when f-CNTs are incorporated into polymeric composites represent a promising route to design ideal materials for aerospace related structural applications • However, the field requires much deeper fundamental research
Functionalized CNTs • Chemical functionalized CNTs significantly decreased the electrical conductivity of epoxy nanocomposites due to unbalance polarization effect and physical structure defects due to severe condition during acidic treatment process • Non chemical functionalized CNTs are more suitable for the electrical applications • Chemical functionalization of CNT is still necessary for increase dispersion quality and strengthens the interfacial bonding strength with polymer matrix, which more important in structural applications
