Historic documents, protection

Another use for inert atmospheres is in protecting historic documents. Suppose the Declaration of Independence were simply left on top of a table for people to see. The paper and ink in the document would soon begin to react with oxygen in the air. They would both begin to decay. Before long, the document would begin to fall apart. 

The same polyester can be fabricated into a particularly strong film called Mylar. Mylar polyester film is used for the long-term protection of artwork and historical documents because of its transparency, strength, and inertness. Mylar is popular for its use in the manufacture of balloons for festive occasions. Mylar was also used to cover the 94-foot wingspan of the Gossamer Albatross, a human-powered aircraft used to fly the English Channel in 1979. Only two pounds of the polyester was needed to cover the entire wingspan, and the polyamide Kevlar was the material used for construction of the rudder of this aircraft In the United States, production of polyester fibers exceeds 3 billion pounds per year. 

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