Plastic is a solid whose basic components are synthetically or semi-synthetically produced polymers (molecule chains) with organic groups. A basic distinction is made between chain polymerisation and step polymerisation.
A plastic workpiece consists of millions of very long, intertwined chains of molecules, which are composed of constantly repeating monomers (basic units). The plastic polypropylene consists z. B. from multiple repeating propylene units.
Plastics have the outstanding property that their technical characteristics (formability, hardness, elasticity, breaking strength, temperature and heat resistance and chemical resistance) can be varied widely through the selection of manufacturing processes, starting materials and the admixture of additives.
Plastics are processed in many ways and are used e.g. as packaging materials, textile fibers, floor coverings, and are components of adhesives and cosmetics. They are used in electrical engineering and vehicle construction and are further processed into molded parts, semi-finished products, fibres, foils and much more.
Precursors of plastic existed in all cultures. In the 17th and 18th centuries, naturalists brought elastic masses from Brazil and Malaysia that were obtained from milky tree sap. The term rubber was introduced for this in Germany, and a rapidly growing rubber industry has developed since the middle of the 19th century. Later, cellulose nitrate was developed in England to impregnate textiles, and shellac was developed in the USA. The patent for polymethyl methacrylate (PMMA) registered by Otto Röhm in 1928 marked the beginning of an era that has lasted to this day.
In the years 1910 to 1950, plastic went from being a substitute material to being a material for industrial mass production. Even today, the plastics industry is still a growth sector, with the production capacities in Asia overtaking the regions of Europe and North/South America in the meantime.