- Plastic
fantastic
Everybody knew plastics didn't conduct electricity. Then Professor of Chemistry
Alan MacDiarmid found one that did. For this he recieved a Nobel Prize.
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October 26, 2000
Q&A
Alan MacDiarmid
BY SANDY SMITH
The father of conducting organic
polymers said he owes his success to his colleagues, his students
and the institution that has been his home for 43 years.
Photo by Candace diCarlo
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Success, the old saw goes, has many fathers. Alan MacDiarmid has been
careful to acknowledge all of them whenever he talks about his latest
achievement.
And since winning the 2000 Nobel Prize in Chemistry Oct. 11, MacDiarmid,
the Blanchard Professor of Chemistry, has praised them all many times
over: at a same-day press conference for the local media, at receptions
in his honor thrown by his department and by President Judith Rodin, in
numerous interviews, including this one with the Current.
And still the reporters come, asking how it came to pass that MacDiarmid,
Alan Heeger and Hideki Shirakawa, working at Penn in the late 1970s, discovered
that with a little tweaking, they could make plastic conduct electricity.
That discovery ultimately led to the first homegrown Nobel in the sciences
for Penn.All of the basic research that led to the discovery of conducting
polymers took place in Penn labs — including the one right down the
hall from MacDiarmid’s office, which the local section of the American
Chemical Society named a historic site earlier this year. Heeger was a
Penn physics professor at the time.
Since we figure you’ve already heard about the history of MacDiarmid’s
research in one of the many stories that have appeared in the wake of
the Nobel, we’ll just give you the quick summary here. The man loves
pretty colors, and one day in the early 1970s, Heeger asked him to look
at an inorganic polymer that produced lovely golden crystals and films.
It proved to be a superconductor, the first non-metallic one. He later
spoke about this work in Japan, where Shirakawa, then a young Tokyo Institute
of Technology professor, told him of an organic polymer — a silvery
film consisting of impure polyacetylene — that also appeared conductive.
MacDiarmid invited Shirakawa to join him and Heeger for a year at Penn,
and, armed with $21,650 in seed money from the Office of Naval Research,
they went to work. They soon found that by exposing the polyacetylene
to bromine vapor, they could raise its conductivity significantly —
and from there, an entire field of chemistry was born, one that now promises
a number of novel commercial applications.
MacDiarmid is quick to point out that he and his Nobel co-laureates
could not have done their groundbreaking work on conducting polymers without
crucial government support, first-rate student researchers and an environment
that encouraged people to step outside the confines of their disciplines.
Q. What are some of the possible uses for these conducting polymers?
A. Penn has worldwide patent coverage on plastic rechargeable batteries.
Then other interests have involved electromagnetic shielding. … We’ve
looked into mixing polyaniline with traditional plastics to cut out electromagnetic
interference [from electronic equipment].
The really, really hot area at the moment is light-emitting diodes. In
1990, Professor Richard Friend of Cambridge University in England showed
that conducting polymers in their laundered form — certain of them
could emit light of different colors according to the polymer when anywhere
from about three volts to 10 volts were applied across them. Alan Heeger,
one of my co-awardees, started off a company in California which brought
up to an industrial-commercial stage light-emitting diodes from these
conducting polymers, and I understand a few months ago he sold his company
to DuPont.
One of the [other] things in which there is a huge amount of interest
is plastic electronics. Philips, the electronics company in the Netherlands,
has beautiful little plastic chips about the size of a 50-cent piece.
Flexible, you can bend them … and these they will be producing for
about one cent each. They will never replace durable silicon-chip technology
for use in outer space, where you’re going to have a satellite which
is going to last for 20 years, but if you just want to have something
which will be used once, which will have a life of, say, 20 days or 20
weeks or 20 months, and where cost is the important thing, then this is
fascinating.
Q. You’re originally from New Zealand. What led you to leave?
A. Well, New Zealand is one of the far-flung outreaches of the British
Commonwealth. Most of the people — well, not the Maori population
— were [migrants from Britain, and] we all considered it a new country.
It became a British possession in 1840, and we always referred to [Britain]
as home, even though you were born, your parents were born in New Zealand.
And all the young people always wanted to go home, which meant England.
We would see the ships in the harbors, and we’d say, Oh, that’s
the home boat, meaning that’s a boat that would go to England.
So I put in for a couple of fellowships to go to England, and I was turned
down. And at about this time the United States was just starting the Fulbright
Fellowships. So I put in for a Fulbright Fellowship, and I was fortunate
enough to get one. I went to the University of Wisconsin, where I did
a Ph.D. in radiochemistry, and while I was there, I applied for a fellowship
from New Zealand Shell [Oil Company] to go to Cambridge [University],
and I was lucky enough to get that. ...
[After] Cambridge, I was a junior assistant, temporary lecturer at the
University of St. Andrew’s [in Scotland] for a few months. And my
wife, who was American, lived in Wisconsin, found it bitterly cold there
and her health wasn’t too good. So we then searched around and then
we got this position at Penn. And it was interesting — I’m the
only person, I think, who’s ever been hired by Penn sight unseen.
And at the lowest possible position on the totem pole.
Q. A lecturer?
A. No. I was hired as an instructor. I was hired sight unseen by Charlie
Price, who was the chairman of the department then. [He is now an emeritus
University Professor.] I guess they thought they were taking quite a gamble.
… I got promoted after a year to assistant professor, and then things
started going. Incidentally, if anybody could help me locate Charlie Price,
I would be most grateful. He [once] said to me, Alan, you were the best
thing I ever did during my stay here at the University. So you can fool
some of the people all of the time.
Q. But why have you stayed here for all 43 years?
A. I, like many people on our faculty, have had many offers to move
elsewhere. And I find that Penn has such a very good academic atmosphere.
Has very good students at both the undergraduate and graduate level, and
has very good opportunities for research, so I thought, really, Penn is
pretty much ideal.
Q. I know they’re thrilled in 100 College Hall. How about your
students in Chemistry 461? What’s been their response?
A. Well, I must give you a lovely, cute little story. On Wednesday
morning, which was the morning after the announcement, I had the midterm
exam, and I was sorry it was the midterm exam right then. So just before
it started, a charming young lady in the second row put up her hand and
asked, May I say something? I said yes. She said, I liked your photo in
the DP. Do I get an A for that? And I said, No, you get an A-plus-plus
for that. [laughter]
One of the secretaries in the department told me a few hours later that
she was going up on the elevator on Wednesday morning. And in the elevator
was one of my Chemistry 461 students going to the exam. … And [the
student] said, Oh, at least my parents will be pleased, now they’re
paying out all this money to Penn, but they’ll have a Nobel laureate
as my teacher in senior inorganic class.
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