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(inspired of “Chemistry and physicochemistry of Polymers” by Mr. Fontanille and Y. Gnanou, Dunod, Paris, 2002) What a polymer? It is a term used since 1866 by Berthelot who, in an article published in the Bulletin of the Chemical Society of France, noted that “styrolene (styrene), heated at 200° during a few hours, transforms itself into a resinous polymer”. It was the first recognized synthetic polymer. But it was Hermann Staudinger, in the year 1920, which was the first to propose the concept of polymers in the sense we use today. It lead to the Nobel prize in 1953 for his work which is at the base of all science of macromolecules. It is, however, only during the following decade that the “macromolecular” theory definitively replaced the “micellar” theory to which it was opposed. Man had always used natural polymers in the form of textile fibres and material shapes. The scarcity of some of them had mobilized researchers, at the end of 19th century, to transform natural polymers into artificial polymers. Thus, they created nitrocellulose (celluloid, artificial silk) for the replacement of the ivory, silk…, or many materials presenting of the new properties likely to generate new applications (ebonite by extreme vulcanization of the natural rubber). An important stage had been reached with the industrial production of the first synthetic polymers (Bakelite, synthetic rubbers). But it is a result of the theory suggested by Staudinger that their variety increased in a considerable way. He was the seminal researcher and the majority of synthetic polymers used today result from its work. In 1933, the firm ICI (Imperial Chemical Industries), in the United Kingdom, succeeded for the first time in the polymerization of ethylene. The result was a completely new material: low density polyethylene. It is about a polymer of extreme importance, still produced nowadays on the scale of several tens of million tons. It is during this same decade (1938), that W. Carothers and his research team (Dupont de Nemours), discovered polyamides (nylons) and showed that the chemistry of polymers could generate materials whose mechanical characteristics could be higher than those of natural polymers. As of the decade 1940-1950, polymers were used as substitutes for a number of traditional materials. This operation was not always treated with the respect it deserved, which lead to a reputation of poor quality of the objects manufactured. The research carried out in the industrial and academic laboratories resulted in reducing and eliminating the principal defects of the polymers, which are now used for the most sophisticated applications and the most advanced fields of technology. The juries of the Nobel prize wanted to honor this still young science, by awarding the prizes of Chemistry or Physics to a number of its representatives: Staudinger was the rewarded first, but subsequent prizes include Ziegler and Natta, Flory, McDiarmid, Shirakawa, Heeger, and more recently, the trio of Chauvin, Grubbs and Schrock. Pierre-Gilles de Gennes was also honored by the jury with the Nobel Prize; polymers were only one of his centers of interest but his name is known to of all polymer scientists for his theories in the field of the science of polymers. Because of their economic importance, the industry of polymers has produced a multitude of research tasks and stimulated, upstream, academic research of great quality. This is strongly supported by industrial circles with their strength in developing basic research into products. The universality of polymers is now well established. They are present in all fields of industrial production as an additive or structural materials and are impossible to circumvent. The improvement of their properties gradually removed their bad reputation and, at the present time, one can now say “There are no bad polymers, only bad applications of them”. In the table hereafter, some major dates which marked the important stages of this young science are shown. Important stages in the history of polymers
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