All the hippest, hottest scientists in 1988 wore Polytherm outfits. Except then they weren't hot anymore, because the polyethylene glycol-treated fabric keeps you cool in warm weather, and warm in cold weather. The chemical absorbs heat when it melts, and releases it when it solidifies. It also has some pleasant side effects: Polytherm clothes don't wrinkle, shrink or stain as easily as regular fabric. So if you spill hot coffee on yourself, your shirt will repel it and then cool you right down.
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