A polymerisation or polycondensation process is used to make plastics from natural materials such as cellulose, coal, natural gas, salt, and crude oil.
Natural, organic resources such as cellulose, coal, natural gas, salt, and, of course, crude oil are used to make plastics. Crude oil is a complicated mixture of thousands of components that must be treated before usage. The distillation of crude oil at an oil refinery is the first step in the manufacturing of polymers. This divides the heavy crude oil into fractions, or groups of lighter components.
Each fraction is made up of a variety of hydrocarbon chains (chemical compounds made up of carbon and hydrogen) with varying sizes and structures.
One of these fractions, naphtha, is a key ingredient in the manufacture of plastics.