|
|
The Accidental Superpolymer
| Article
# : |
15043 |
|
|
Section : |
NATURAL SCIENCE
|
| Issue
Date : |
9 / 1988 |
2,591 Words |
| Author
: |
Michael Woods
|
In the spring of 1938, a young chemist named Roy J. Plunkett was trying to synthesize new refrigerant gases at an E.I. du Pont de Nemours and Company laboratory in Deepwater, New Jersey.
His assistant, Jack Rebok, opened the valve on a small cylinder of tetrafluoroethylene gas--similar to products known as Freon--which Plunkett was using in the experiments. The gas hissed softly from the cylinder valve through flowmeters and into a chamber where it reacted with other chemicals.
Unexpectedly, the flow of gas stopped.
"Hey, Doc," Rebok asked, "did you use all this stuff up last night?"
"No, I don't think so," Plunkett responded, noting that the cylinder, which rested on a laboratory scale, still contained about two pounds of what had to be tetrafluoroethylene gas.
Plunkett opened the valve completely and ran a wire into the valve opening, but no gas escaped. He unscrewed the valve, tipped the cylinder upside down and, to his amazement, a white, waxy powder spilled onto the laboratory bench. He cut the cylinder open with a hacksaw and obtained a larger quantity of the granular material.
Unexpected Discovery
That was mankind's first glimpse of Teflon, the marvel of the plastics world, which is celebrating its 50th birthday this year. Teflon's birth ranks as one of the classic examples of serendipity in science--happy, unexpected discoveries made by accident to the enormous benefit of mankind.
Plunkett could have been forgiven if he had missed the discovery of Teflon. For the opportunity came when he was young and inexperienced, only a few years after he completed his graduate work at Ohio State University. And Teflon was not the goal of his research at Du Pont. It did not come as the result of a trial-and-error process or a carefully designed research effort to polymerize fluorocarbons. The discovery required an essential characteristic referred to by Louis Pasteur, the great nineteenth-century French scientist, who observed, "Chance favors the prepared mind." It also required the curiosity and motivation to investigate the unexpected.
Plunkett recalled that it was immediately obvious, upon seeing the white powder inside the cylinder, that the tetrafluoroethylene had spontaneously polymerized. And there was no question about investigating its properties. Indeed, it is possible to sense Plunkett's mounting excitement from the terse entries in his laboratory notebook as he found the mysterious substance resistant to ever-more-powerful chemicals.
Yet the initial discovery was only the beginning of the Teflon story. During World War II and even until the late 1950s, Teflon had limited use, primarily because it was a carefully guarded military secret. It played a key role in the development of the atomic bomb. The process of producing highly enriched or weapons-grade uranium requires combining natural uranium with fluorine to form uranium hexafluoride. Physicists and engineers needed a material for use in seals and lubricants in reaction vessels that
...
Read Full Article
|
|
