Cornell Center for Materials Research

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Not All Recyclables Are Created Equal
Question
Now that we are all recycling, what are some of the products that are made from recycled materials that we should be buying to complete the cycle?

Question
The short answer to this question is anything made with glass, aluminum, and steel. According to Lynn Leopold, Recycling Specialist for Tompkins County Solid Waste Mgmt. Div., items made of these materials are completely recyclable. What makes these three more attractive than plastic or paper? Recycled glass, aluminum, and steel can be melted and processed in the same way as their mined counterparts. Aluminum and iron (steel) are metallic elements that remain undamaged after each round of recycling. Glass, aka silicon dioxide, is composed of the elements silicon and oxygen and also remains pristine during many lifetimes as a beverage container.

Conversely, paper and plastic are composed of fibers and polymers. These fibers and polymers can degrade over time just like the fibers in a well-worn shirt or teddy bear. Office paper tends to be composed of the newest fibers, and is recycled to provide recycled office paper, which in turn becomes cardboard. Well-worn fibers tend to find their resting place in the form of tissue paper that most of us are very pleased not to recycle. Not all polymers find themselves in a downward spiral towards the dump. Some polymers, like PETE (code 1), are broken back down to their starting components and reused completely or the polymers are reformed into fibers for clothes and plastic lumber. Chemists are discovering new methods to make polymers from renewable and completely recyclable materials, but until these are available glass, aluminum, and steel provide the most bang for your recycling buck.

 
Edited on: 19 June 2007 2:37 pm