Electrical
Conductivity
Only a small volume fraction of Nanostrands are required to impart conductivity in a wide variety of matrix materials. Many polymers have been rendered conductive, including thermosets, thermoplastics, paints, elastomers and adhesives. By mixing nanostrands into a matrix, volume resistivities as low as 0.001 ohm-cm have been achieved, at less than 20% loading. However, if the matrix is added to the compressed nanostrand preform, then a volume resistivity of .0002 ohm-cm can be achieved at about 20% loading. This is a remarkable amount of conductivity for a material that is still over 80% matrix.
Surface resistivities as low as 0.050 ohm-per-square have been achieved for sprayed nanostrand polymer mixtures on non-conductive substrates, and as low as 0.010 on carbon fiber substrates. When mixing nanostrands into a resin, the conductivity is also affected by the diameter, length, aspect ratio and orientation of the nanostrands.
Mixing Methods
Nanostrands are unique from other nanomaterials in that it does not take much energy to disperse them into most resins. In fact, too much energy will shear the strands apart, and reduce them to particulate powder. Low shear and low viscosity methods have shown the most success for dispersing nanostrands. Low volume and low loading applications have been successful with very simple dispersion methods, while larger volume or more highly loaded systems have been very successful with centrifugal dispersion tools.
Only a small volume fraction of Nanostrands are required to impart conductivity in a wide variety of matrix materials. Many polymers have been rendered conductive, including thermosets, thermoplastics, paints, elastomers and adhesives. By mixing nanostrands into a matrix, volume resistivities as low as 0.001 ohm-cm have been achieved, at less than 20% loading. However, if the matrix is added to the compressed nanostrand preform, then a volume resistivity of .0002 ohm-cm can be achieved at about 20% loading. This is a remarkable amount of conductivity for a material that is still over 80% matrix.
Surface resistivities as low as 0.050 ohm-per-square have been achieved for sprayed nanostrand polymer mixtures on non-conductive substrates, and as low as 0.010 on carbon fiber substrates. When mixing nanostrands into a resin, the conductivity is also affected by the diameter, length, aspect ratio and orientation of the nanostrands.
Mixing Methods
Nanostrands are unique from other nanomaterials in that it does not take much energy to disperse them into most resins. In fact, too much energy will shear the strands apart, and reduce them to particulate powder. Low shear and low viscosity methods have shown the most success for dispersing nanostrands. Low volume and low loading applications have been successful with very simple dispersion methods, while larger volume or more highly loaded systems have been very successful with centrifugal dispersion tools.