Plastic is a polymer, chains of simple organic chemicals (monomers), linked together in long chains. The monomers are synthesized in refineries, from oil. The linking of the monomers in the polymer chain is done inside polymerization reactors until the desirable average molecular weight is achieved for the polymer. Then dyes and other additives are added to the molten polymer and the material is extruded into filament, granules or flakes and cooled.
Plastics are sold in these forms as raw materials to the various manufacturers. Recycled plastic can be molten and re-extruded or directly crushed into granules or torn into flakes.
Plastic products are made out of raw plastic using a host of moulding techniques which always involve mixing and melting of the raw material inside a screw extruder.
Most plastic molecules are just hydrogen and carbon atoms, or mostly hydrogen and carbon with some oxygen, sulfur, nitrogen or chlorine atoms as well. They take advantage of the ability of carbon atoms to bond their electrons together in long flexible chains in order to create long flexible molecules.
When we combine monomers, we generate polymers or plastics.The plastic production process begins by heating the hydrocarbons in a “cracking process.” The resulting resins may be molded or formed to produce several different kinds of plastic products with application in many major markets.