The plastics industry manufactures polymer materials—commonly called plastics—and offers services in plastics important to a range of industries, including packaging, building and construction, electronics, aerospace, and transportation. It is part of the chemical industry. In addition, as mineral oil is the major constituent of plastics, it is regarded[by whom? as a part of the petrochemical industry. Besides plastics production, plastics engineering is an important part of the industrial sector. The latter field is dominated by engineering plastic as raw material because of its better mechanical and thermal properties than the more widely used commodity plastics.
source: wikipedia