Authors:
Historic Era:
Historic Theme:
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July/August 1998 | Volume 49, Issue 4
Authors:
Historic Era:
Historic Theme:
Subject:
July/August 1998 | Volume 49, Issue 4
It is one of the most famous oneword lines in the history of Hollywood: “Plastics.” But however intergenerationally challenged that half-drunk friend of Dustin Huffman’s parents may have been in The Graduate, he was right about the importance of the materials revolution in the 20th century.
It has been a curiously silent revolution, however. When we think of the scientific triumphs of this century, we think of nuclear physics, medicine, space exploration, and the computer. But all these developments would have been much impeded, in some cases impossible, without.. . plastics. And yet plastic remains, as often as not, a term of opprobrium.
Plastics are mostly synthetic materials that, because of their chemical nature, can be cast, molded, drawn out, extruded, and otherwise manipulated into an infinity of shapes. Before the 1930s, almost everything people saw or handled was made of materials that had been around since ancient times: wood, stone, metal, and animal and plant fibers.
The first wholly synthetic substance with practical applications was called Bakelite, after its inventor, Leo Hendrik Baekeland, an immigrant from Belgium. As has happened again and again in the history of plastics, Baekeland was looking for one thing, in this case a substitute for shellac, and found another. Bakelite, initially marketed in 1909 (the year the word plastic was first used as a noun), is made by mixing phenol with formaldehyde (do not try this at home). Because, like most synthetic materials, it is nonconductive, Bakelite was mostly used as an electrical insulator. Its most visible use was in telephones, most of which were made of Bakelite until the 1950s.
Bakelite is what chemists call a polymer, a molecule composed of a long string of smaller molecular units, called monomers. Nature produces a host of polymers—cotton and silk, for instance—and the most famous polymer of all of course is DNA, the molecule of life.
Another natural polymer is rubber. Known since antiquity in the Americas, where the rubber tree is indigenous, rubber was first put to practical, if prosaic, use by the great eighteenthcentury chemist Joseph Priestley. He discovered that it could be used to rub off pencil marks on a piece of paper, an attribute that gave the substance its modern popular name. The Scotsman Charles Macintosh used it to make waterproof clothing. Then, in 1839, the American Charles Goodyear discovered that adding sulfur to rubber prevented it from becoming brittle at low temperatures and liquid at high ones, greatly increasing its utility. Rubber was soon indispensable in a number of industrial applications. With the arrival of the bicycle and the automobile, it became indispensable to everyday life.
But there was one big problem regarding rubber. Being native to the New World tropical rain forest, there were only a very limited number of places in the world where the trees could grow in commercial quantities on plantations. Most of these areas were part of the British