Metal rubber is a broad, informal name for several
conductive plastic polymers with metal
ions
An ion () is an atom or molecule with a net electrical charge.
The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conven ...
produced by NanoSonic Inc. in cooperation with
Virginia Tech
Virginia Tech (formally the Virginia Polytechnic Institute and State University and informally VT, or VPI) is a public land-grant research university with its main campus in Blacksburg, Virginia. It also has educational facilities in six re ...
. This
self-assembling nanocomposite
Nanocomposite is a multiphase solid material where one of the phases has one, two or three dimensions of less than 100 nanometers (nm) or structures having nano-scale repeat distances between the different phases that make up the material.
The id ...
is flexible and durable to high and low pressures, temperatures, tensions, and most chemical reactions, and retains all of its physical and chemical properties upon being returned to a
ground state
The ground state of a quantum-mechanical system is its stationary state of lowest energy; the energy of the ground state is known as the zero-point energy of the system. An excited state is any state with energy greater than the ground state. ...
. NanoSonic’s Metal rubber™ is an electrically conductive and flexible
elastomer
An elastomer is a polymer with viscoelasticity (i.e. both viscosity and Elasticity (physics), elasticity) and with weak intermolecular forces, generally low Young's modulus and high Deformation (mechanics), failure strain compared with other mate ...
. It can be mechanically strained to greater than 1000% of its original dimensions while remaining electrically conductive. As Metal rubber can carry data and electrical power and is environmentally rugged, it can be used as a flexible and stretchable electrical conductor in the aerospace/defense, electronics, and bioengineering markets.
[Lalli, Jennifer & Claus, Richard & Hill, Andrea & Mecham, Jeffrey & Davis, Bradley & Subramanayan, Sumitra & Goff, R.. (2005). Commercial applications of Metal rubber (TM). Proceedings of SPIE - The International Society for Optical Engineering. 5762. 10.1117/12.606788. ]
Properties
Metal rubber needs to contain around 1% metal ions to maintain its conductive properties, allowing the material to retain an elastic quality as well as keeping the heavy metal component low. Metal rubber has a strain of 300% although the sheet itself can be mechanically strained to greater than 1000% of its original dimensions. The elastic modulus is 0.01 GPa and the service resistivity per square sheet is .1–100 ohms. The maximum service temperature is 170 degrees Celsius (338 degrees Fahrenheit), while the minimum service temperature is –60 degrees Celsius (–76 degrees Fahrenheit). It carries an electrical charge that can be used to transport power and data. It is typical of an elastomer to be an insulator but Metal rubber is highly conductive like metals.
Applications
Metal rubber is made through a modified molecular-level self-assembly production process using precursors which NanoSonic produces in-house. Materials are manufactured in a variety of sizes and geometries. The possible uses of such a product include
body armor
Body armor, also known as body armour, personal armor or armour, or a suit or coat of armor, is protective clothing designed to absorb or deflect physical attacks. Historically used to protect military personnel, today it is also used by variou ...
, durable electronic sensors, various
aerospace
Aerospace is a term used to collectively refer to the atmosphere and outer space. Aerospace activity is very diverse, with a multitude of commercial, industrial and military applications. Aerospace engineering consists of aeronautics and ast ...
-building materials, and alternate commercial building materials. Several industries have unique needs that are met by Metal rubber's characteristics.
1. Aerospace/Defense
:Robust under harsh conditions (high and low temperature/pressure).
2. Electronics
:Stretchable electrical conductors/sensors.
3. Bioengineering Markets
:Flexible with no corrosion. Useful for joint replacement instead of heavy metal implants.
:The thicker dimensions of the Metal rubber can be used for artificial muscles because of the flexibility and conductive properties for bio-electrical signals.
Current products
NanoSonic currently offers a variety of products that incorporates Metal rubber's unique properties.
1. Metal rubber Cables
:This product can be used to replace heavy metal power and data cables as well as make conductive fabrics and CNTs. Also used in lightweight
EMI shielding and can be used as an elastomer cover for hoses and tubing.
2. Metal rubber Shielding
:Based on nanostructured Metal rubber and carbon nanotubes, it is lightweight, environmentally durable and allows radio wave frequency selection and broadband connection.
3. Metal rubber Sensors
:Allows for shear force and pressure sensors in addition to water and wind tunnel analysis at moderate/high air pressure.
External links
Science Central – Metal rubber video 2004-Sep-14
NanoSonic's websiteVideo of Electrostatic Self-Assembly Process Animation
References
{{Virginia Tech
Virginia Tech
Conductive polymers