Why are unsaturated hydrocarbons useful as petrochemical feedstocks?

Unsaturated hydrocarbons are highly valued as petrochemical feedstocks primarily because of their chemical reactivity. Unlike saturated hydrocarbons, which contain only single bonds and are relatively unreactive, unsaturated hydrocarbons possess one or more double or triple carbon-carbon bonds.123

These multiple bonds are chemically unstable and reactive, allowing the molecules to be easily transformed into a wide variety of other chemical products. Their utility in manufacturing stems from several key characteristics:12

• Addition Reactions: The double or triple bonds allow other atoms or groups to be added directly to the molecule, a process that serves as the foundation for synthesizing numerous industrial chemicals.4
• Polymerization: The presence of a double bond is the essential feature that enables olefins like ethylene and propylene to undergo polymerization. Under the influence of catalysts, heat, and pressure, these bonds open to link molecules into long, chainlike structures, forming polyolefins such as plastics and synthetic resins.5
• Versatility: Because they are reactive, they serve as essential building blocks for diverse products, including polyester fibres, synthetic rubber, solvents, and various chemical intermediates.2