It is this range of properties together with their low cost that has driven the annual worldwide demand for plastics to reach 245 million tonnes ( PlasticsEurope 2008) today. Plastics have a range of unique properties: they can be used at a very wide range of temperatures, are chemical- and light-resistant and they are very strong and tough, but can be easily worked as a hot melt. The success of plastics as a material has been substantial they have proved versatile for use in a range of types and forms, including natural polymers, modified natural polymers, thermosetting plastics, thermoplastics and, more recently, biodegradable plastics. Development of modern plastics really expanded in the first 50 years of the twentieth century, with at least 15 new classes of polymers being synthesized. Developmental work continued through the nineteenth century on natural/synthetic polymers producing such notables as celluloid for billiard balls, polyvinyl chloride (PVC), which is used in myriad applications, and viscose (rayon) for clothing. In 1839, Goodyear invented vulcanized rubber, and Eduard Simon, a German apothecary, discovered polystyrene (PS).
In the intervening years, man has relied increasingly on plastics and rubber, first experimenting with natural polymers, horn, waxes, natural rubber and resins, until the nineteenth century, when the development of modern thermoplastics began.
Humans have benefited from the use of polymers since approximately 1600 BC when the ancient Mesoamericans first processed natural rubber into balls, figurines and bands ( Hosler et al.
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