Early synthetic polymers
Early synthetic polymersEarly Synthetic Polymers
Polymers have been around longer than we have. In fact, polymers are as old as life itself, as all life on earth is based on three types of polymers, namely DNA, RNA, and proteins. But this report is about some of the earliest synthetic polymers, that is, polymers made by humans, specifically, the cellulose derivatives.
The very first synthetic polymer was of course leather, a modified natural polymer, an artificially crosslinked form of the proteins found in animal skins. Leather tanning was discovered thousands of years ago, but I'm going to talk about some synthetic polymers that came a bit later. These are the cellulose derivatives. They are also derivatives of a natural polymer, cellulose. They hold a special place in polymer
history, because their invention in a lot of ways was the beginning of an explosion in the invention of synthetic polymers which continues to this day.
Cellulose derivatives are forms of cellulose, a polymer found in wood, cotton, and paper, which have been chemically altered. Scientists first started to make them in the second half of the nineteenth century, long before we really even knew what a polymer was. The very first came about when a scientist reacted cellulose, in the form of cotton, with nitric acid. The result was cellulose nitrate. Cellulose nitrate, also called gun cotton, turned out to be a powerful explosive. It soon replaced common gunpowder as the explosive charge in the ammunition for rifles and artillery.
Cellulose nitrate was also used to make an early polymer containing composite material, safety glass. This was a sandwich made of a sheet of cellulose nitrate in between two layers of glass. The sheet of cellulose nitrate held the glass together when it was broken. This was great for automobile windshields. The glass would still break, but the broken pieces would stay stuck to the cellulose nitrate sheet, instead of flying into the faces of...
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