Smart rubber

Smart rubber is a polymer that is able to "heal" when torn.

The edges of a tear can be held together, and they will simply re-bond into apparent solidity.

How it works

This is done by producing a polymer that depends only on hydrogen bonding to hold itself together, rather than also on covalent bonding and ionic bonding, which are present in normal rubber.

Unlike the latter two types, hydrogen bonding can occur simply by pressing two faces of a substance together.

Real-world versions

Materials of this type are still in development, for example a type invented at the Industrial Physics and Chemistry Higher Educational Institution ESPCI in Paris, France. Their translucent, yellowish-brown rubber is synthesized from fatty acids and urea. It is still too soft for most anticipated practical applications, like rubber gloves and shoe soles [http://technology.newscientist.com/channel/tech/dn13354-smart-rubber-promises-selfmending-products.html?feedId=online-news_rss20] .

Among the potential problems of the material is that it would also bond to itself any other way it came into contact, like upon closing the fingers or hand of a glove. This may be solved by coating objects made from the rubber with some other polymer, so that the smart rubber is only exposed to itself when torn.