Majority of the most commonly used plastics(commodity plastics) are derived from these chemicals :

1. Ethylene

2. Propylene

3. Butadiene

4. Benzene

These chemicals are intern derived from Naptha obtained during petroleum refining process or from Natural Gas,after processing.

A flow chat of the sources of commodity plastics and some other important plastics,rubbers and fiber materials is given below

Source: ICPE - ENVIS