Polyaniline is among a family of conductive polymers, and has properties similar to some metals. It was discovered as “aniline black” in an organic form as part of melanin, a type of organic polymer, in 1934. Melanin does many things in nature, including protecting the skin by regulating UV exposure through a polyaniline interaction. In a natural form, polyaniline is usually found folded with other polymers. In the late 1990s, it became evident that it was a flexible and highly useful polymer, and could be used in applications ranging from intelligent windows to computer chips.
This polymer is unusual because it is a type of semiconductor. Polyaniline can be configured to conduct across a wide range, from being utterly non-conductive for insulation use to highly conductive for other electrical purposes. Like other polymers, it is highly flexible, which makes it appealing for manufacturing use. Polyaniline comes in a granular form that can be mixed with an organic chemical and painted or sprayed onto a substance to form a smooth layer. It can also be molded into various shapes, as was done in 2000 when it was used to manufacture a computer chip.
Polyaniline is made by polymerizing aniline molecules through a chemical reaction with a substance such as hydrochloric acid. This is usually performed by oxidizing the aniline molecules and mixing them slowly. Depending on the desired conductivity of the polyaniline, the resulting polymer will be exposed to other chemicals in a process called doping. Doping it leads to a more stable polymer, and will also allow it to conduct current evenly.
There are a variety of applications for polyaniline, which can be easily combined with other polymers to form desired shapes. It is frequently utilized in the computer industry where it is incorporated into static free packaging, flexible electronic components, and in testing to shield against electromagnetic radiation. It also appears in construction applications, and is frequently included in corrosion resistant treatments for various surfaces.
In the 1990s, it was predicted that polyaniline could change the face of the manufacturing world, allowing the rapid and easy construction of electronic components, insulators, and a wide range of gadgets and tools for modern society. The successful construction of a computer chip in 2000 suggested that the material would work in practical applications, and new uses are constantly being discovered, with more manufacturers adopting the versatile material for a wide range of applications every day.