Image Gallery: Green Science
Image Gallery: Green Science

Could you imagine using biodegradable plastic? Bioplastics may help make that possible. See more green science pictures.

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Bioplastics -- that is, plastics derived from plants -- have the potential to alleviate some of the long-term pollution problems caused by conventionally made plastics. From manufacturing processes that release less global warming related pollution to the ability to biodegrade, bioplastics seem environmentally friendly. However, bioplastics are currently more expensive than standard plastics, and they might not be as eco-friendly as they seem.

What's the difference between bioplastics and regular plastics? Most plastics are made through petrochemical processes. In other words, they start out as the chemical byproducts of oil refining, which are turned into a variety of plastics through chemical processes that form long molecular chains known as polymers. These polymers give plastics their structure. You can find out more details on the manufacture of petrochemical plastics in How Plastics Work.

Bioplastics, on the other hand, are derived from plant-based sources. They can be made from cane sugar, corn, or from plant byproducts like wood bark and corn husks. Pepsi is even trying to incorporate potato and orange peels into the manufacture of bioplastics [source: de Guzman]. Switchgrass is another great source for bioplastics – it grows pretty much anywhere, is drought resistant, and grows quickly. Since it isn't a primary food source, using it for bioplastics won't affect food prices.

You may have heard that bioplastics are biodegradable, but this isn't necessarily true. The term bioplastics refers to the plant-based manufacturing method. Some types of bioplastic are biodegradable, some aren't. Some bioplastics will degrade in your home compost bin, while some require industrial composting. In fact, many bioplastics won't degrade at all if placed in a landfill with other garbage.

With so much potential, yet so many challenges, what does the future hold for bioplastics?