The Boy Chemist at 75, continued
The Great Discovery began over a cup of green tea in Tokyo, in the mid-1970s. MacDiarmid and his host, Dr. Hideki Shirakawa, a polymer chemist, talked about a silly lab error: A Korean graduate student in Shirakawas lab, hindered by language barriers, mistakenly used 1,000 times the requisite amount of catalyst for a chemical reaction. The result was a jelly-like plastic that shone like metal. As mistakes go, the story should have ended there.
But chance favors the prepared mind, and MacDiarmid was prepared. He coaxed his Japanese colleague into spending a year at Penn to help him study this unique material. Along with a third researcher, Dr. Alan Heeger, then a professor of physics at Penn, they would discover a unique class of plastics that conduct electricitywhich would eventually win them worldwide recognition in the chemistry Nobel.
In a brilliant interdisciplinary collaboration, the three researchers enhanced the conductivity of that first shimmery polymer, polyacetylene, by spiking it with the highly conductive element, bromine. They then worked around the clock to develop similar polymers of even greater conductivity. We were very excited because we were getting observations that no one else had previously attained, MacDiarmid says. But we were very doubtful about whether we were correct or not. The researchers gained more confidence in their results once others began to duplicate their data.
With the birth of the field of conducting polymers, an international floodgate of research in the chemistry and physics of these novel plastics swung open. Twenty-or-so conducting polymers have since been developed throughout the world, and they have been used in cell-phone and pager displays, transistors, light-emitting diodes, and lightweight electromagnetic shields. Now in development are virtual-reality displays and electroluminescent wallpaperwhich can provide power-saving illumination for occupants, who will be able to manipulate the paper colors and patterns at willthat use conducting-polymer technology. Penn holds some 20 patents on conducting polymers.
At the time MacDiarmid and his two colleagues carried out the meat of their work on conducting polymers, there were no laptops, cell phones, or other immediate applications for their new technology. Conducting polymers were an answer waiting for the pertinent question, which had not yet been asked, he says.
For MacDiarmid, the pleasure was derived from the journeythe intellectual pursuit of answersmore than the destination, but he points to a general moral regarding the practicality of scientific investigations. So often when I give a lecture people say, Thats very interesting, but how can we use it?, to which I reply, Of what use is a beautiful poem?
Certainly, there is something almost poetic in MacDiarmids hard-line science. In a lecture on science and creativity presented last December at the Einstein Forum in Potsdam, Germany, MacDiarmid discussed the limitations of conventional wisdom. Twenty-five years ago, he explained, plastics were considered strictly electrical insulators. His revolutionary research, however, bucked this long-held notion. Because MacDiarmid, Heeger, and Shirakawa yielded to real-life observations rather than to theory, plastics having high electrical conductivityconducting polymers, electronic polymers or synthetic metalsare now well known.
What is at the edge of scientific or social acceptability today is often commonplace tomorrow, he says. Whether something is good or bad, hot or cold, black or white, theres so much in the eye of the beholder. The greatest limitation on social progress is the mind.
For example, We were always told that the inert gasesthose with eight electrons in their outer shellcannot form chemical compounds. Eventually one of these, xenon, was found to be reactive, he continues. Then people throughout the world started reporting the production of xenon compounds. And all those years, people had accepted [the alternative] as fact. But finally, peoples minds were released to produce new compounds.
MacDiarmid tells his students and research assistants to question everything, verbal or written, and its a rule he lives by as well. Dr. Page McAndrew, senior research scientist at Atofina Chemicals, Inc. in King of Prussia, Pennsylvania, worked in MacDiarmids lab for four years in the early 1980s. He can still hear the oft-repeated words of his Ph.D. adviser: MacDiarmid used to say, Theories come and theories go, but the facts go on forever. So you have to get the facts correct.
MacDiarmid is a man of many mottoes, and sprinkles his conversation with those that inspire him the mostsome borrowed, some his own: The harder I work, the luckier I seem to be. When you stop learning, you start dying. Be very slow to say that others are wrongno matter how strongly you think you are correct. And, perhaps his favorite, We all stand on the shoulders of giants, a humbling saying that, he says, pays homage to the work of other people in other years, other centuries.
Quotes help MacDiarmid to reinforce his convictions, he says, and that is why he likes them. Perhaps his strongest conviction is the power of persistence. Before embarking on his research on conducting polymers, MacDiarmid had had a thriving career in the field of silicon chemistry for two decades. When McAndrew came to work with him in 1980, he was impressed by his optimistic, indefatigable approach to challenges. He made sure that for every observation we made, we were going to get some good out of it. When they tried to produce a battery using conducting polymers, the initial results were not what they had hoped for, McAndrew remembers. But he said, Theoretically, it should give us x, y, and z. So he kept changing the design until he got x, y, and z. It was a process that took many months, says McAndrew, a time scale in which a lot of people would have just bagged it.
MacDiarmid credits his persistence to growing up poor, which, he says, made him self-reliant. Born in Masterton, New Zealand, in 1927, MacDiarmid remembers well the Great Depression, which hit the country hard during the 1930s. His father, an engineer, became unemployed during this time. During grade school, MacDiarmid had an early-morning job delivering milk by bicycle for a local farmer. The family had no telephone or refrigerator, they rationed their food, and Alan and his four older siblings rotated through the same bath water during their weekly bath night. From his close-knit clan, he learned interpersonal skills that would serve him in his professional life.
He would help his older brother to make printing paper and mix developer chemicals for his darkroom at home. He remembers the awe and curiosity he had for this magical process whereby a photographic image appears on a previously blank sheet of paper. When he was about 10 years old, his interest in chemistry became crystallized when he found one of his fathers old chemistry text books. I spent hours poring over the pages in complete confusion, but with burning curiosity! he recalls. The turning point came when he found a childrens book called The Boy Chemist at his local library. Elated that he finally had a chemistry book he could understand, MacDiarmid renewed the book continually for over a year, carrying out most of the experiments in it.