The accidental inventor - some inventions result from unexpected consequences - special issue: The Science of Creativity

Roy plunkett was only 27 years old and had been working as a chemist at the Jackson Laboratory at E. I. du Pont de Nemours and Company for just two years when, in the spring of 1988, he made a discovery that brought him lasting fame. He had been trying to invent a new type of Freon, a class of compounds that in the 1930s, were proving to be immensely useful as the principal gases in refrigerators and air conditioners. Today we call them chlorofluorocarbons, or CFCs, and know them to be a major culprit in depleting the atmosphere's ozone layer, but back then they were miracle substance - safe, non-flammable substitutes for toxic and even explosive refrigerants.

On an April morning 58 years ago, the young chemist could not have suspected that he was about to discover a material with such strange and unexpected properties that they had hardly even been dreamed of, a material that would eventually become an indispensable part of everything from space capsules to heart valves to frying pans - and one that had absolutely nothing to do with refrigeration. Roy Plunkett was about to discover Teflon.

The importance of Plunkett's story, however, lies not so much in the triumph of invention and commercialization as in what it suggests about the nature of invention itself. invention is often though of as systematic problem, solving, the kind that supposedly goes on at the well-manicured campuses of corporate research laboratories. In fact, many important inventions arose, and continue to arise, from die creative use of an accident or mistake. This is a unique and somewhat neglected form of creativity, every, bit as ingenious and awesome as the more deliberate sort.

Much of the act of invention is shrouded in mystery, to be sure. Even when people set out to act purposefully and rationally, they wind up doing things they did not intend. in principle, the accident or the unexpected obstacle that gives rise to a creative invention is not all that different from the unexpected traffic jam that forces us to drive through a new and interesting neighborhood, the pesky weed that turns out to enhance our garden's variety, or the empty shelf at the supermarket that spurs us to improvise a new recipe. But in practice, events like Plunkett's are far fewer, and we cannot help asking ourselves: What makes it possible to turn the unlooked-for-chance into novel fortune? Not surprisingly, we surroundings: a mind supple enough to turn a screwup into a creative opportunity, and an environment that makes such creativity possible.

By the time plunkett started working at Du Pont, the most widely used form of Freon was tetraflorodichloroethane, also known as refrigerant 114. This was manufactured bv a joint Du Pont-General Motors company called Kinetic Chemicals, which supplied it exclusively to the Frigidaire divisions of GM. Despite the Du Pont-GM link, the chemists at the Jackson Laboratory, were responding to the requests of other refrigerator manufacturers for an equally effective refrigerant that could be sold more widely. Plunkett and his colleagues were thus attempting to manufacture a Freon variant that would get around Frigidaire's patent control of refrigerant 114.

Plunkett hypothesized (correctly) that he could start with a compound called tetrafluoroethylene, or TFE., and cause t to react with hydrochloric acid to yield the desired alternative. To test this idea, he decided to make a large quantity of TFE, hitherto a rare and little studied compound. Following suggestions in the chemical literature, Plunkett set up an apparatus to make a hundred pounds of the gas. When asked later "Why a hundred pounds?" Plunkett replied that he needed a good bit, of the gas not only to test for refrigerant properties but also to conduct toxicological tests on animals, and a hundred pounds just seemed like a round number."

Because making this much TFE was a complex operation, Plunkett decided to get it out of the way first. A hundred pounds was a lot of TFE, and to store it he needed to round up ill the storage canisters he could get his hands on. The most convenient ones to obtain were metal cans, similar to the cans now used for hair sprays, insect poison, and other products in which CFCS serve as a propellant. He set his canisters on top of dry ice so that the TFE inside would liquefy and the pressure inside the cans would be kept low. Precisely these steps set the stage for Plunketts surprising discovery.

On the morning of April 6, Plunkett and his assistant, Jack Rebok, set up the apparatus for inducing their gas to react midi hydrochloric acid. They put a cylinder of TFE on a scale, opened a valve to release the pressure, and allowed the vapor to enter a heated reaction chamber. Then they released a stream of hydrochloric acid into the chamber. The two scientists had run this process so many times in the weeks before that they probably felt they could do it in their sleep, but on this day something went wrong. Once they had put the apparatus together and opened the proper valves, Rebok reported that nothing was coming out of the TFE cylinder. The heft of the cylinder told the men it wasn't empty, and the scale confirmed that it should contain most of the original gas, but even with the valve opened completely, nothing at all came out. They stuck a wire through the valve to unclog it, but even nothing happened.