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Materials Research Essay Research Paper Material science

Materials Research Essay, Research Paper

Material science is the study of the properties of solid materials and how those properties are determined by a material s composition and structure. Most engineers have the primary function of relating the design and production of machinery and components. Materials science and engineers are involved with all aspects of engineering and provide the best material for a large variety of applications. In the workplace materials science and engineers can specify, test, and qualify the materials used by their companies. They can also perform the research and development that is necessary to provide the materials of the future that will enable other engineers to extend the capabilities of their products. Material science and engineers work with all classes of materials such as steel, fiber ceramic composites, metallic super alloys, and electronic polymers. Materials science and engineers use different kinds of methods to advance the use of all materials and discover the properties of different materials (What do Material Scientists and Engineers Do?, Georgia Institute of Technology).

With today s new technology there are many things that materials science and engineers are doing that they could not do before. One of the newest advancements made by materials science and engineers is the discovery of conductive polymers. A conductive polymer is a chemical compound or mixture of compounds formed by polymerization whose electrons need to be free to move and not bound to the atoms. In the past one major difference between polymers and metals is their low electrical conductivity. However, there has recently been a new class of organic polymers capable of conductivity. Commonly referred to as doping, this new process through reduction and oxidation causes polymers to become conductive. The advantages to the discovery of these new conductive polymers are a full range of conductivity from insulators to metallic conductors (Technology Development, Panipol). I believe that the discovery of conductive polymers is going to change the way we live dramatically in the near future. Conductive polymers can be produced quickly and cheaply; they can increase the effectiveness of phones and televisions, and are energy savers. Some of the materials that are used now as conductors will be replaced by some kind of polymer that is more effective and useful.

Polymer conductivity was discovered coincidently in the 1970 s by chemists Hideki Shirakawa, Alan J. Heeger, and Alan G. MacDiarmid (Vetenskapsakademien, Nobel Prize). Japanese chemist Shirakawa found that it was possible to synthesize hydrocarbon polyacetylene, a flat molecule with an angle of 120 degrees between the bonds, in a new way. Shirakawa s discovery enabled him to control the proportions of cis-and trans-isomers in the black polyacetylene film that appeared in the reaction vessel. One day Shirakawa made the mistake of adding too much a thousand-fold catalyst. Shirakawa s mistake surprisingly added a beautiful silvery film. The silvery film was trans-polyacetylene and as Shirakawa changed the temperature and concentration of catalyst a corresponding reaction occurred. This discovery was decisive for what was about to happen (Vetenskapsakademien, Nobel Prize).

Meanwhile in the United States, chemist MacDiarmid and physicist Heeger were experimenting with a metallic-looking film of the inorganic polymer sulphur nitride. All of MacDiarmid s, Heeger s, and Shirakawa s research would have come to an end if MacDiarmid and Shirakawa didn t meet accidentally during a coffee break. MacDiarmid immediately invited Shirakawa to the University of Pennsylvania in Philadelphia after hearing about Shirakawa s discovery of an organic polymer that also gleamed like silver. The three started modifying polyacetylene by oxidation with iodine vapor. After Shirakawa informed MacDiarmid that the optical properties changed in the oxidation process, MacDiarmid suggested that they ask Heeger to look at the films. One of Heeger s students measured the conductivity of the iodine-doped trans-polyacetylene and discovered that the conductivity had increased ten million times (Vetenskapsakademien, Nobel Prize). These discoveries led to the conclusion that doping introduces carriers. In the summer of 1997, Shirakawa, MacDiarmid, and Heeger published their findings and won a Nobel Prize for work on conductive polymers. Since then, the field of conducting polymers has greatly expanded and it has led to the development of such devices as plastic transistors and plastic batteries (Dance, 50).

Since the discovery of conductive polymers there have been many applications made to our society. These applications include the emission of light in new ways and new developments in the battery. The light from a light bulb results after the metal wires that conduct electricity light up after a strong enough current is passed through. By the principle of electro luminescence that is used in photodiodes, a type of plastic, polymers can also be made to light up. Photodiodes are more energy saving and generate less heat than light bulbs. Today the uses of photodiodes have caused an extensive commercial interest (Vetenskapsakademien, Nobel Prize). Conductive polymers have also affected the use of batteries. The lightweight characteristic of plastics is perfect for the low weight requirement of batteries for portable devices and vehicles (Salamone, 497). With the discovery of the process of electrochemical doping of polyacetylene, a basis for the electrochemistry of the battery was developed. The availability of a reversible electrochemical doping system provides a rechargeable battery system. The all plastic battery has conducting polymers functioning as both cathode acceptors and anode polymers. This process causes the battery to be lighter, more effective, and last longer (Salamone, 497-498). Conductive polymers have made a major impact in our society by making some of the everyday things that we use more effective. Turning on a light or using something that contains batteries can become more efficient just by the use of conductive polymers.

Conductive polymers have a great commercial potential because they can be produced quickly and cheaply. The use of conductive polymers in the future will make the use of batteries, telephones, and many other electronic devices more efficient. Some electronic components based on polymers will soon find a place in consumer products where low processing costs will be more important than high-speed production (Vetenskapsakademien, Nobel Prize). The number of conductive polymers continues to expand and now includes a wide range of molecular configurations as viable polymer candidates. Researchers today know that there are still many significant breakthroughs yet to be made and that there are still many phases of development ahead (Salamone, 501).

The importance of conductive polymers and different materials in today s world shows the importance of materials science and engineers will continue to be in demand in the future (What do Material Scientists and Engineers Do?, Georgia Institute of Technology). Conductive polymers will continue to be made more efficient by material science and engineers in the future. The use of conductive polymers will become more popular worldwide and help make almost anything they are used in more efficient. It will take a combination of material science and all different kinds of engineers to make polymer conductivity as efficient as it can be. I see conductive polymers as a major step in saving time, energy, and money. With the combined efforts of all different kinds of engineer s conductive polymers could be one of the most efficient discoveries of the past fifty years. However, conductive polymers will not be able to become more advanced without the combined effort of all engineers, because each individual engineer depends on every other engineer.




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