Ethylene tetrafluoroethylene, colloquially known by its abbreviation ETFE, is a fluorocarbon-based polymer (a fluoropolymer): a kind of plastic. It was designed to have high corrosion resistance and strength over a wide temperature range. In addition it has a high melting temperature and does not emit toxic fumes when ignited.
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At the Beijing Olympics, the National Aquatics Center, or "Water Cube," is surrounded by a light-weight polymer foil that significantly reduces the energy that goes into construction. The thin transparent material, called ETFE (Ethylene Tetrafluoroethylene), is segmented into 3,000 air-filled cushions that let in light but hold in heat.
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