The production of plastics requires chemical ingredients such as ethene, propene and ammonia as well as various other ingredients such as methanol, ethanol or acetic acid. For their extraction, elements are needed, including oxygen (O), nitrogen (N), sulphur (S), chlorine (Cl) or fluorine (F) and, last but not least, carbon (C) and hydrogen (H). Hydrocarbons (CmHn) form the chemical backbone of carbon-based polymers and thus of all common plastics.
Usually, hydrocarbons [CmHn] are obtained from fossil resources such as crude oil, natural gas or coal; a small part is produced from renewable raw materials. After appropriate pre-treatment and fractionation, smaller hydrocarbon units (monomers) are cross-linked by chemical reactions such as polymerisation, polycondensation or polyaddition to form larger units, the macromolecules (polymers). These become plastics. Which source the ingredients come from is irrelevant for the manufacturing process. What matters is the result.