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most sober ot economic forecasters. ! But while the generation gap seems ‘ to have disappeared, plastics are ; still very much with us. ■ Plastics are but one of a host of ! man-made polymers formed by che! mically combining small molecules ! into large, complex chains or stringlike molecules.
Molecules are the smallest parti| cles of a chemical substance capable ' of independent existence. To put their size in perspective, there are as many molecules in a teaspoon of water as there are teaspoons of water in the Atlantic Ocean.
Polymers are crucial to living things, providing basic structural materials and participating in life processes. They occur naturally in proteins, cellulose, wool, starches, and other organic material. They also occur in inorganic substances such as diamonds, quartz, and feldspar. Rubber is one polymer that is both natural and man-made.
Besides the one-liter plastic soft dnnk bottles and rubber gloves you might find about the kitchen, polymers are encountered daily in various forms of nylon, paper, concrete, paint, lacquers, films, styrofoams, and fibers. Polymers package the food you buy, form the dishes you eat from, and wrap the garbage you toss away. They compose familiar household products ranging from carpets to toothbrushes. And if your house is relatively new, you may find that the water pipes are plastic — lighter, stronger and less expensive than the older and heavier cast iron type.
But polymers pre not as new as you might think. Since 1920, the fundamental knowledge necessary for
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