MacDiarmid, << muhk DIHR mihd, >> Alan Graham (1927-2007), a New Zealand-born American chemist, won a share of the 2000 Nobel Prize in chemistry. He received this award for the discovery and development of plastic materials in which electric current can flow. Ordinary plastic materials cannot conduct (carry) current. MacDiarmid shared the Nobel Prize with two colleagues in this work, the American physicist Alan J. Heeger and the Japanese chemist Hideki Shirakawa. The three scientists conducted the research that led to their Nobel Prize at the University of Pennsylvania. They published their discovery in a scientific journal in 1977.
MacDiarmid and his colleagues won the prize for their work on special polymers, the basic substances of which plastics are made. A polymer is a huge molecule formed by the joining of many smaller molecules into a long chain. The small building units are called monomers. A monomer, in turn, consists of two or more joined atoms. The atoms within a monomer are joined to each other by means of connections known as bonds. Bonds between atoms also join the monomers that make up a polymer.
There are several kinds of bonds. MacDiarmid and his colleagues developed conducting polymers by manipulating covalent bonds. A covalent bond consists of a pair of electrons that are shared by two atoms. An ordinary electric current consists of a flow of electrons; the manipulation of the bonds freed a small number of electrons from bonds so that these electrons could flow.
A number of products use conductive polymers, and others are being developed. Major applications include antistatic materials for photographic film; solar cells, which use sunlight to generate electric power; and displays in mobile telephones and television sets.
MacDiarmid was born in Masterton, New Zealand, on April 14, 1927. He received a Ph.D. degree in chemistry from the University of Wisconsin in 1953 and a Ph.D. in chemistry from Cambridge University in the United Kingdom in 1955. He joined the faculty of the University of Pennsylvania in 1955 and taught there for more than 45 years. MacDiarmid became a United States citizen in 1966. MacDiarmid died on Feb. 7, 2007.
