polymer compositeconducting polymer

Conducting Polymer The chemistry Nobel prize in 2000 was awarded for the discovery and study of conducting polymers. Alan J. Heeger, Alan G MacDiarmid, Hideki Shirakawa (白川英樹) Conducting Polymers • Polymers are typically utilized in electrical and electronic applications as insulators where advantage is taken of their very high resistivities. • Typical properties of polymeric materials: Strength, flexibility, elasticity, stability, mouldability, ease of handling, etc. Conducting Polymers • Can provide electromagnetic shielding of electronic circuits • Can be used as antistatic coating material to prevent electrical discharge exposure on photographic emulsions • Can be used as hole injecting electrodes for OLEDS • Usage in electroluminescent displays (mobile telephones) • In use as emissive layer in full-color video matrix displays • Some are promising for field-effect transistors (Usage in supermarket checkouts) • Some absorb microwaves: stealth technique Conductivities [...]...•As synthesized conductive polymers exhibit very low conductivities It is not until an electron is removed from the valence band (p-doping) or added to the conduction band (ndoping, which is far less common) does a conducting polymer become highly conductive •Doping (p or n) generates charge carriers which move in an electric... electrodes This movement of charge is what is actually responsible for electrical conductivity Conjugation of p orbitals Conducting Mechanism • While the addition of a donor or an acceptor molecule to the polymer is called "doping ", the reaction that takes place is actually a redox reaction • The first step is the formation of a cation (or anion) radical, which is called a soliton or a polaron Pn ⇔ [Pn+... dianion) known as a bipolaron [Pn+ A– ] ⇔ [Pn2+ 2A– ] (reduction oxidation) • Alternatively after the first redox reaction, charge transfer complexes may form between charged and neutral segments of the polymer when possible [Pn•+ A–] + Pm → [(Pn Pm)•+ A–] Use triiodide to oxidize polyacetylene as a means to measure glucose concentration Discharge Protection Corrosion Protection . Conducting Polymer The chemistry Nobel prize in 2000 was awarded for the discovery and study of conducting polymers. Alan J. Heeger, Alan G MacDiarmid, Hideki Shirakawa (白川英樹) Conducting Polymers •. Polymers • Polymers are typically utilized in electrical and electronic applications as insulators where advantage is taken of their very high resistivities. • Typical properties of polymeric. materials: Strength, flexibility, elasticity, stability, mouldability, ease of handling, etc. Conducting Polymers • Can provide electromagnetic shielding of electronic circuits • Can be used as antistatic