Elasticity and conductivity are often mutually exclusive in industrial materials, making it difficult to find a material that one could twist and bend and use for electric conduction at the same time. Electrical wires, often made out of copper or some other metal stretched out into threadlike widths, were invented to try and bridge the gap but was impractical if one wished to apply them to a surface. Metals are also highly reactive to chemicals and this is a problem if one wanted to use them for everyday purposes.

As its name suggests, Metal Rubber combines the properties of rubber and metal. It is highly elastic and chemically stable. At the same time, Metal Rubber is also durable and highly conductive.

One of the researchers at NanoSonic came up with the idea while looking for a way to add protective coatings to fiber optic cables. Six years later, the company released the first commercial Metal Rubber. The product was welcomed by the manufacturing industry because of its unique properties. Even if it sells for around $1000 for every six-inch square, one-millimeter sample, orders still poured in.

Manufacture of Metal Rubber

A 12×12-inch sample of Metal Rubber takes three days to manufacture. It is done using robots built specifically for the purpose and through the nanotechnology process, Electrostatic Self-Assembly (ESA), where molecules are piled on in layers on a surface.Metal Rubber

The process begins with a substrate – the surface on which molecules will be formed. This is alternately dipped into water-based solutions containing cationic substances and anionic polymers or polymer complexes. The substrate is repetitively dipped in each solution until layers build up on it. The substrate is then removed, leaving behind a piece of Metal Rubber.

The molecules from each substance form a very strong, near-perfect arrangement. Because of their energy configurations, the molecules from the different substances tend to seek each other out and form very tight bonds. The resulting material also inherits the properties of whatever substances were present in the aqueous solutions used.

Future Application of Metal Rubber: Flexi-Computers

Many companies already see industrial and commercial applications for the unique properties of Metal Rubber. It could, for example, be used to replace the traditional flex cable (known to break with extended usage) which is present in many mobile phones and laptops today. Metal Rubber's application in consumer electronics is also seen by many large companies; particularly, Metal Rubber is being considered as a replacement for today's circuits.

Because of its flexibility, Metal Rubber is also seen by many to be a step closer towards ultraportable computers and wearable electronics. There are also moves to use metal Rubber in the manufacture of artificial muscles; artificial muscles react – they flex and change their shape – when they are stimulated by electricity similar to biological muscles, hence the name.

NanoSonic is yet to scale their operations up to a commercial level, citing lack of funding as a big challenge. This is the main obstacle right now to extensive use of Metal Rubber.