Alkenes, also referred to as olefins, are a class of hydrocarbons characterized by the presence of at least one carbon-carbon double bond. These unsaturated compounds are highly reactive, making them invaluable in various industrial applications.

One of the primary uses of alkenes is in the production of plastics. For instance, polyethylene, a widely utilized plastic, is synthesized from the alkene ethene ($C_2H_4$). This versatile material is commonly found in packaging, bottles, and numerous everyday products.

Alkenes also play a crucial role in the manufacture of synthetic rubber. The alkene butadiene ($C_4H_6$) undergoes polymerization to create a type of rubber that closely resembles natural rubber. However, synthetic rubber can be produced more cost-effectively and in larger quantities. This material is essential in a variety of applications, including tires, gloves, and adhesives.

In the realm of detergents, alkenes are similarly important. The alkene propene ($C_3H_6$) is utilized to produce linear alkylbenzene sulfonate, a vital component in many laundry and dishwashing detergents. This compound is favored for its biodegradability and its minimal contribution to foam formation in natural water bodies, such as rivers and lakes.

Beyond these applications, alkenes serve as intermediates in numerous chemical synthesis processes. For example, ethene ($C_2H_4$) is crucial in the production of ethanol ($C_2H_5OH$), a key ingredient in alcoholic beverages, as well as ethylene glycol ($C_2H_6O_2$), which is commonly used in antifreeze formulations. Additionally, propene is employed to manufacture propylene oxide ($C_3H_6O$), which is essential in producing polyurethane foams.

These examples illustrate just a few of the many significant roles that alkenes play in industrial processes, highlighting their importance across a wide range of applications.