Strictly, any of a large class of chemicals (as distinct from fuels) derived from petroleum and natural gas .
The category has been broadened to include a much larger range of organic compounds and a few inorganic compounds (including carbon black, sulfur , and ammonia ). Some materials cannot be classifed unequivocally because they have alternative sources ( benzene from coal, hydrocarbon s. Petrochemicals used as raw materials (feedstocks) include ethylene , propylene, butadiene, benzene, toluene , xylene, and naphthalene . Among the myriad petrochemical products are plastics (e.g., polyethylene , polypropylene, polystyrene), soap s and detergent s, solvent s, drug s, fertilizer s, pesticide s, explosive s, synthetic fibres and {{link=rubber">rubbers s, paints, epoxies , flooring and insulating materials, luggage, and recording disks and tapes.