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Geoffrey Coates: Most people would acknowledge that plastics are, they are really essential. [---1---]

You're listening to Geoffrey Coates, a chemist at Cornell University. [---2---]

Geoffrey Coates: [---3---] So, going to a renewable resource - something that's plentiful in the environment - is of a lot of interest.

[---4---] Coates said the biggest challenge was finding the right catalyst - that's a chemical that converts other chemicals from one form to another.

Geoffrey Coates: Carbon dioxide is a gas, and obviously plastic is a solid. [---5---]

Coates said that his environmentally friendly - plastics biodegrade more quickly than traditional plastics.

Geoffrey Coates: [---6---]

Our thanks today to the Camille and Henry Dreyfus Foundation. E&S, is a clear voice for science.

【視聽版科學(xué)小組榮譽(yù)出品】
To me, it'd be really hard to imagine a day without plastics. He's created a range of new plastics from renewable resources. There's a lot of interest in trying to get away from oil as a way to make plastics. One of his plastics is made using carbon dioxide, which Coates calls a 'virtually unlimited' resource, since it's abundant in the atmosphere. So, carbon dioxide is mixed with other chemicals, and they're hooked together to make these large molecular chains that we know as plastics. They have linkages in the backbone of the plastic that react with water over longer periods of time, unlike polyethylene and polypropylene, which can last for decades, if not centuries.