Raw materials used to make plastic include carbon-rich oil and carbon compounds, called monomers, that are mixed with oxygen, sulfur or nitrogen. Organic compounds, such as ethylene, propylene, styrene, phenol, formaldehyde, ethylene glycol, vinyl chloride and acetonitrile, can also be found in plastics.
Organic or non-organic substances can be added to the plastic mix to change the nature of the plastic. The average content of additives is 20 percent by weight. Additives and fillers are used to reduce the cost of plastic production. Thermoset, or thermosetting, plastics cannot change form once they've cooled. In contrast, thermoplastics are more malleable, and when heat is applied to them they can return to their original form or be easily molded into another shape.
In 1870, chemist John Hyatt reacted nitrocellulose with camphor to make celluloid, a plastic polymer that was then used in camera film, pool balls, dental plates and ping-pong balls. In the 1930s, a chemist from the company Dupont, Wallace Carruthers, invented a plastic polymer made from the condensation of adipic acid and a certain type of diaminohexane monomer. The mixture created a type of plastic that could be formed into a more fibrous substance, like a fabric. Other plastic derivatives include Dacron, Styrofoam, polystyrene, polyethylene and vinyl.