Smart rubber
Encyclopedia
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.
ing to hold itself together, rather than also on covalent bond
ing and ionic bond
ing, which are present in normal rubber.
Unlike the latter two types, hydrogen bonding can occur simply by pressing two faces of a substance together.
s and urea
. It is still too soft for most anticipated practical applications, like rubber gloves and shoe soleshttp://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 when torn.
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...
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 bondHydrogen bond
A hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, such as nitrogen, oxygen or fluorine, that comes from another molecule or chemical group. The hydrogen must be covalently bonded to another electronegative atom to create the bond...
ing to hold itself together, rather than also on covalent bond
Covalent bond
A covalent bond is a form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms. The stable balance of attractive and repulsive forces between atoms when they share electrons is known as covalent bonding....
ing and ionic bond
Ionic bond
An ionic bond is a type of chemical bond formed through an electrostatic attraction between two oppositely charged ions. Ionic bonds are formed between a cation, which is usually a metal, and an anion, which is usually a nonmetal. Pure ionic bonding cannot exist: all ionic compounds have some...
ing, 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 acidFatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
s and urea
Urea
Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....
. It is still too soft for most anticipated practical applications, like rubber gloves and shoe soleshttp://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 when torn.