00:00:00BOHNING: [...] This is Jim Bohning of the Center for the History of Chemistry, speaking with Dr. Roy Plunkett in his hotel rin the Marriott Marquis, on April 14, 1986, on the occasion of the 191st national meeting of the American Chemical Society. Dr. Plunkett, you were born on June 26, 1910 in New Carlisle, Ohio. Can you tell me
something about your father and your mother--their names and their occupations?
PLUNKETT: My father was Joseph Henry Plunkett. He was born and raised in
Franklin County, Virginia. He was the son of a mountaineer farmer. Before he
went to Ohio in 1907 he met my mother, whose name was Elizabeth May Garst, of
Roanoke, Virginia. Her father was both a farmer and a railroad man and they
00:02:00lived right outside of Roanoke. She went to visit my father in the summer of
1909 and while she was there they decided to elope to Kentucky and get married.
That was the beginning of my parents' family life. I came along nine months later.
BOHNING: But they didn't stay in Kentucky?
PLUNKETT: That's right. They went back to Ohio. I was born in New Carlisle,
Ohio, which is about fifteen or twenty miles northeast of Dayton, near Vandalia.
My father was a farmer all of his life. He spent most of it in Ohio in Miami
00:03:00county. He did return to Virginia for a short period in the early 1920s but it
didn't suit him and he went back to Ohio.
BOHNING: You were raised on a farm?
PLUNKETT: I was raised on a farm except for that year and a half when I was in
Roanoke, Virginia. I graduated from Newton High School in Pleasant Hill, Ohio,
in 1927. I was one of twenty-four in the graduating class.
BOHNING: I'd like to talk about the schools you attended but before I do, let me
ask if you have any brothers or sisters?
PLUNKETT: I have three sisters and a brother. My brother is the youngest. He is
nineteen years younger than I, and the three sisters are spaced in-between.
00:04:00BOHNING: As you went through school in Ohio, were there any teachers that had
any particular influence on you?
PLUNKETT: Yes. For the first six or seven years, I went to a one-room
schoolhouse. There were two or three different ones until about 1925, when my
father and mother went back to Virginia for awhile. When I came back to Pleasant
Hill I went into high school. I had a teacher there named William White. He was
a math-science teacher and he had some influence on me. I remember one time that
00:05:00somebody asked me what I wanted to do. I said I wasn't sure what I wanted to do
but I wanted to get my hands on the reins. There was another teacher by the name
of Virden Thompson who I believe is still living in Pleasant Hill, Ohio. He was
principal of the high school for a long number of years. He influenced me and my
brother and sisters.
BOHNING: Did you have any chemistry when you were in high school?
PLUNKETT: I had very little chemistry in high school. This was a little country
school, even though it was a consolidated school. They didn't get into chemistry
00:06:00very much, although Mr. White was interested in chemistry and I got a little
interest from him. I don't remember it too well. At least he spurred my interest
BOHNING: What was it like growing up in a small country town in Ohio?
PLUNKETT: I was a young kid. My parents were Dunkards, Church of the Brethren
Dunkards. I was raised pretty strictly in the teaching of the Dunkard Church. I
was raised not to fight, turn the other cheek and so forth. I didn't get into
much trouble in those days. [laughter]
BOHNING: You went to Manchester College in Indiana. How did that selection came about?
00:07:00PLUNKETT: Manchester College is a church school of the Church of the Brethren.
My family and I went to the Church of the Brethren in Pleasant Hill, Ohio. When
I graduated from high school I was interested in going to college. It was the
natural flow of things, to be interested in going to Manchester College.
BOHNING: In making your decision to go to college, had there been any influence
from your family to do that, or was that something you did on your own?
PLUNKETT: I think the urge was as much mine as anybody's, but my mother
definitely taught me to learn. There is one example I can tell about my mother.
My younger sister came home one day and said to my mother, "So-and-so gets a
00:08:00dollar when she gets an 'A'." My mother said to her, "Well, you better worry
about what you will get if you don't get an 'A'." [laughter]
BOHNING: Had you selected an area to concentrate in when you went to Manchester?
PLUNKETT: I had not. I think I didn't know enough at that point in time. I had
enough to know that I wanted to start studying chemistry some, and I did start
taking chemistry in Manchester. I was influenced a lot there. Dr. Carl W. Holl
was a chemistry teacher and Dean of the College at Manchester when I was there.
00:09:00He had a Ph.D. from Ohio State. I had a lot of inspiration from him. I got on
his staff in the college and did some laboratory assistantship work for him. He
encouraged me and definitely had an influence in my going on to the university.
BOHNING: Can you describe the department at that time? How many people were in
the chemistry department?
PLUNKETT: It was a small college. At that time, in the late 1920s and early
1930s, there was a total student population of five or six hundred. The
chemistry department was pretty small. I would say there were only two on the
staff of the chemistry department -- Dean Holl, and another man by the name of
00:10:00[Don] Martin. Martin graduated the year I was a freshman and went on the staff
to teach as an assistant professor.
BOHNING: How many other students were there in chemistry?
PLUNKETT: If I think through the four years that I was there, there were
probably eight or ten that were chemistry students. One of my friends who was at
Manchester when I was there was later an outstanding chemistry student at Ohio
State. He combined his schooling, doubling up summers and winters, and got
00:11:00through a year and a half ahead of me. He got his Ph.D. at Ohio State and as
soon as I mention him, you're going to know him. He turned out to be a Nobel
Laureate. That's Paul J. Flory.
BOHNING: Oh, yes. I should have made that connection earlier. Did you have much
interaction with Flory?
PLUNKETT: We had a lot of interaction. We started school at the same time. We
were together essentially three years at Manchester. As I recall we roomed
together with two other fellows at an outside boarding house for at least one
year. We got into a lot of scrapes together as well.
BOHNING: What kind of scrapes, if I may ask?
PLUNKETT: Halloween pranks. [laughter]
00:12:00BOHNING: That's very interesting. You said you roomed at a boarding house off
campus. I know costs were quite different, but what kind of support did you have
while you were going to school? How did you meet your expenses?
PLUNKETT: I only had a few sources. I had direct help from my father, what
little bit he could do. I had help from the college and I had part time work. I
did janitorial work. I did laboratory assistant work in the chemistry department
and I did work downtown in a clothing store on weekends. Then in addition, I got
some help, backed by my father, in loans from a banker back in my hometown.
00:13:00BOHNING: You have already mentioned Professor Holl's influence on you. As you
finished your four years at Manchester had you thought about trying to seek a
job at that point or had you already decided to go on to graduate school?
PLUNKETT: I graduated from Manchester College in the spring of 1932. I don't
know whether you remember that time or not but that was the absolute bottom of
the Depression. I could not find any work tied in with chemistry at that time.
At the urging of Dr. Holl, I wrote to practically all of the universities in the
country. I wrote to one hundred and twenty-five universities, trying to get some
00:14:00assistance to get on their staff to go to school that fall. One of my very good
friends was able to get in at Ohio State. There was only one who could get in,
and he made the grade at Ohio State and I didn't. He was supported by Dr. Holl.
Well, it looked pretty hopeless to me. When I graduated in the spring of 1932, I
owed the college a little bit of money and Dr. Holl said, "You stay on for six
weeks for the first term of summer school and do some work for me and we'll wipe
that out." I did that. I went home and helped my dad on the farm. What was I
going to do? I couldn't find anything.
This friend who had gotten on the staff of the university was from a nearby town
and he was going. We started to pool our resources and he said, "I'll help you
00:15:00out a little if you can get over there and get started." My dad didn't have
anything. We were as poor as church mice. But he said, "I have a friend where we
used to live that owes me fifteen bucks. If you can talk him out of that fifteen
bucks, you can have it." I talked it out of him and I went to the university
with that fifteen bucks in my pocket. And that's all I had. My friend loaned me
a few bucks to help me pay the first fees I had to pay. I washed dishes three
times a day for my meals. I got some help from one of the chemistry professors
00:16:00to do some laboratory work in connection with a practice teaching school nearby.
I wormed my way into the university and eked my way through the first year and
got on the staff for the second year.
BOHNING: When you say you got on the staff for your second year, does that mean
you started to do some teaching?
PLUNKETT: I was a laboratory assistant.
BOHNING: What kind of courses did you take when you first started there?
PLUNKETT: I took nothing but chemistry essentially, except for some required
things. I took German and French to meet my language requirements. I took
advanced organic chemistry, advanced quantitative chemistry, and thermodynamics.
00:17:00BOHNING: Do you recall the professors you had?
PLUNKETT: Yes. The head of the chemistry department was Dr. William Lloyd Evans.
He was quite renowned in carbohydrate chemistry. I worked on him to take me on
as a protégé. I had it in the back of my mind that this would help get me on
the staff. So I went to work for Evans doing research in carbohydrate chemistry,
and did get on the staff. I also did my thesis work in carbohydrate chemistry.
BOHNING: Did you continue your thesis work with Evans?
00:18:00PLUNKETT: Yes I did. Another man on the staff was Melville Wolfrom. He was also
a carbohydrate chemist and he was sort of an inspiration because he was sort of
a renegade, one that you looked up to.
BOHNING: In what respect was he a renegade?
PLUNKETT: He was sort of rough-and-ready and gruff.
BOHNING: Not in keeping with the older school.
PLUNKETT: That's right, not in keeping with the older school. I remember Edward
Mack. He was a physical chemist and I got inspiration from him. I made the
00:19:00remark that "all you have to do is listen to what that guy says. If you remember
what he says you can get an "A" in his class." [laughter] He was good. I
remember another physical chemist, Herrick Johnston. He taught thermodynamics.
He would start out at the beginning of the class period way around in one corner
and would write and talk, write and talk, and go around the room and cover the
blackboard full of equations. If you didn't get them all down and remember them
you didn't get anything out of his course. [laughter]
BOHNING: I was going to ask you earlier about your math background. You've now
mentioned physical chemistry twice. What kind of math experience did you have?
PLUNKETT: I didn't have anything much in high school but algebra and geometry.
00:20:00In college I got advanced algebra and calculus. I didn't get any advanced
mathematics there. I got some when I got into thermodynamics at the University.
BOHNING: You mentioned Paul Flory before. Did you interact with him at Ohio State?
PLUNKETT: Yes. He had been there a year and a half before I got there and was
pretty well established. We used to socialize together and go to meetings
together and things like that. We spent some summer-time activity together. His
father was a Brethren minister and at the time lived in Elgin, Illinois. We
00:21:00visited back and forth. I remember one time while I was at the university we
went to the Chicago World's Fair in the summer of 1933.
BOHNING: Are there any other student colleagues besides Flory that you remember?
PLUNKETT: I remember Homer Wilson, who was the one who loaned me a little bit of
money to help me get started in my first year of graduate school. He was a
pretty smart fellow. He went through and got his degree and worked for Rohm and
Haas. But in the meantime he had fallen in love with a Brethren girl and they
00:22:00got married. He left chemistry and went into missionary work. I lost track of
him for a long time after that.
BOHNING: I realize this was still the Depression but what were your career goals
while you were a student at Ohio State? Were you looking beyond that point?
PLUNKETT: Yes. It wasn't long after I got to Ohio State that I heard of the Du
Pont Company. One of the ways that I heard of the company was through the
fellowship Du Pont established at Columbus. As a matter of fact, Paul Flory had
that fellowship for one year. We were there wondering if anybody was going to
talk to us. I got to the Fall of 1935, and I was in my fourth year at the
00:23:00university. I had already taken my preliminary examinations and was doing my
research work. I got a letter in November of 1935 wanting to know if I would
come to Wilmington, Delaware to talk to some of the Du Pont people at Jackson
Laboratory. The king wants to talk! [laughter] So I came to Wilmington on the
train and went down to the Du Pont building to meet with a gentleman by the name
00:24:00of Ivan Gubelmann. He was one of the top men in the Organic Chemicals
Department. I met with him and he told me how to get across the river to Jackson
Laboratory. I went to Jackson Laboratory and there I met with the head of the
laboratory Bill [William S.] Calcott. He had some tie-in with the neoprene work.
I spent the whole day at Jackson Laboratory, talking with the people there. At
the end of the day Calcott offered me a job. Well, it was a lot different in
00:25:00those days than it was some twenty or thirty years later when guys were getting
eight to ten job offers. I had a job offer, and I said YES! [laughter]
BOHNING: I can appreciate that. Now you still had to go back and finish up.
PLUNKETT: I still had to back to Columbus and finish up. But I had a job! What
do you know, the next week after I got back to the university I got another
letter from Du Pont at Richmond, Virginia! [laughter]
BOHNING: My goodness.
PLUNKETT: But I had already accepted the job at Jackson Laboratory.
BOHNING: What was the Virginia offer?
PLUNKETT: The Virginia offer was in textile fibers. That was a rayon plant in
Virginia. They had some nylon later on in the area and I guess they have Lycra
00:26:00there now. It was textile fibers. I get nostalgic about it, as you see already.
I usually made up my mind in a hurry and if Du Pont's willing to talk to me, I
wanted to go with them.
BOHNING: Had Flory gone down to Du Pont then?
PLUNKETT: Flory was already at Du Pont. He was at the Experimental Station, the
forerunner of the Central Research Department. I think he was already working
with Dr. Wallace H. Carothers.
BOHNING: Did you ever meet Carothers?
PLUNKETT: I met Carothers, but that's all. I never had any working relationship
00:27:00with him. I went to Jackson Laboratory. I had social contact with Flory
afterwards because he met and married a Philadelphia girl and I had married a
Columbus girl and we had a social life together.
BOHNING: What was your first assignment when you got to Du Pont?
PLUNKETT: When I got to Du Pont I was assigned to work in the fluorochemical
field. I've got a story that ties in with what I'm going to talk about on
Wednesday. Would you like to hear it?
PLUNKETT: I'll give you a little bit of the story of how Teflon came about. I'm
00:28:00going to say Wednesday afternoon that I'm proud of my participation in this
development, proud of the company with whom I've worked, proud of what has
happened, and most of all I'm proud of the benefit to mankind from this original
invention. The discovery of PTFE [polytetrafluoroethylene] has been variously
described as an example of serendipity, a lucky accident, or a flash of genius.
Perhaps all three were involved. But regardless, all are agreed as to the
results of that discovery. It has revolutionized the plastic industry and led it
into rigorous applications not otherwise possible.
I want to tell you a little bit about some of the things that had to occur
00:29:00before the discovery of PTFE could take place. In 1851 a U.S. patent was issued
to Dr. John Gorrie for "an appliance for the artificial production of ice in
tropical climates." This can be considered to be a
forerunner of the household refrigerator. Next, the Belgian chemist [Frederick]
Swarts did a lot of work on the substitution of fluorine for chlorine in organic
molecules in the 1890s. He learned how to make
chlorofluoro derivatives of carbon tetrachloride, chloroform, and similar
00:30:00compounds. They were essentially laboratory curiosities until the 1920s. By that
time the household refrigerator had been developed to the point that it
resembled today's machines. But there was one very serious drawback, and that
was the refrigerants. They used such things as ethylene, sulfur dioxide,
ammonia, and methyl chloride which were flammable or otherwise noxious
materials. The refrigeration machines used in those days were not nearly as good
as the machines of today. They would leak and discharge flammable and noxious
gases, much to the consternation of the housewife.
00:31:00[END OF AUDIO FILE 1.1]
PLUNKETT: "Boss" [Charles F.] Kettering of General Motors fame was very much
interested in the refrigerator business and was concerned about the lack of
adequate refrigerants. He called upon Tom Midgley, Albert Henne, and Robert
McNary to look for a safe refrigerant, one that would be colorless, odorless,
tasteless, non-toxic, and non-flammable. These gentlemen then made a study of
00:32:00all the known compounds that might fit the bill, from a physical constant
standpoint, as refrigerants and tabulated them and plotted them in accordance
with the atomic table. Their deliberations led them to postulate that a fluoride
or a fluorocarbon might be suitable. They were not aware, of course, that all
fluorine compounds were poisonous. At least, that's what most people thought in
those days. So they decided to repeat some of Swarts' work and actually did make
some CCl2F2 and found that its physical properties were such that it might be useful.
00:33:00Midgley reported at an ACS meeting in Atlanta in 1930 that they had tested
CCl2F2 and that it had promise as a refrigerant. They demonstrated it and said
it could be safe -- you could smell it and you could stick a match in it.
Midgley reported later when he was being awarded the Perkin Medal that there
might have been some fortuitous circumstances in their work. He called up a
supply house and ordered five one-ounce bottles of antimony trifluoride, the
entire country's supply as far as he knew. They used one bottle of antimony
00:34:00trifluoride and and produced some CCl2F2. They put it into a bell jar with a
guinea pig and the guinea pig just lapped it up and said, "Boy, this is fine."
They were elated that they had made something and it looked like it might be
worthwhile. Later they used another bottle of antimony trifluoride and repeated
the experiments. They did everything as before but this time the guinea pig
kicked up its heels and died. They were dismayed. On further examination they
found that of the five bottles of antimony trifluoride Midgley had originally
gotten, one of them was anhydrous and the rest had water of crystallization. Of
course, when they reacted that with HF, they got some phosgene-like materials,
and that was the cause of their problem. If they had not chosen the anhydrous
00:35:00bottle first they might have given it up as a bad hunch. That was the start.
The people at Du Pont carried on and developed manufacturing processes for a
total of five fluorochloro chemicals over the first five years of the 1930s and
marketed them through Kinetic Chemicals Incorporated, a joint venture of Du Pont
and General Motors.
BOHNING: Do you know anything about the origin of that name, Kinetic Chemicals?
PLUNKETT: I don't know anything specific about how they chose the word kinetic.
No, I don't, and I guess I was too naïve to even ask the question myself in
those days. [laughter]
BOHNING: How long did that company last?
PLUNKETT: That company lasted for fifteen to twenty years, essentially the life
00:36:00of the original commercial patent for refrigerant 12, as Freon refrigerant. When
it was dissolved, Du Pont bought out the General Motors interest and Du Pont
continued to manufacture refrigerants.
PLUNKETT: That company lasted for fifteen to twenty years, essentially the
life of the original commercial patent for refrigerant 12, as Freon
refrigerant. When it was dissolved, Du Pont bought out the General Motors
interest and Du Pont continued to manufacture refrigerants.
BOHNING: Now this was where you came in?
PLUNKETT: This is where I came into the picture. Now, the next thing that I
ought to record is that in 1932, which I'm sure you will recall, was the low
point of the Great Depression. In 1932, I received a bachelor of science degree
in chemistry from Manchester College. At that time, there was no possible way I
could find any employment as a chemist, and I tried to figure out what I was
00:37:00going to do. I would like to have gone on to university but I could hardly see
how it was possible. I wrote to 125 different universities trying to get onto
their assistant staff with no success. Finally, with the collusion of a friend
of mine who was going to Ohio State and had already gotten on the staff, I
wormed my way into the university and spent four years there and ended up with a
PhD and in 1936 I was invited to join the Du Pont company. I did, and was
immediately assigned to work in the fluorine chemical field in the Jackson Laboratory.
BOHNING: Who did you report to when you first arrived? Who were your people?
00:38:00PLUNKETT: I was assigned to work in the fluorocarbon division. Frederick B.
Downing was the division head and Anthony F. Benning was group leader of the
group to which I was directly assigned. The first couple of years that I was at
Du Pont I did whatever jobs came along working on fluorochemical compounds.
Early in 1938 a crisis arose because of the proprietary ownership by Frigidaire
of CF2Cl-CF2Cl (refrigerant 114) which they would not permit to be sold to any
00:39:00competing refrigerator manufacturers. Other refrigerator manufacturers were
asking Du Pont to do something. "Find us a way to get something we can use in
competition with this material." I was assigned to work on the problem of
getting another refrigerant. I and my associates decided to make CF2Cl-CF2H, a
compound which we thought would have some similar refrigerant properties to
Freon 114 which was already being produced.
I set out on a proposition to make this material. Up until that time,
tetrafluoroethylene [TFE] was almost a laboratory curiosity. It had been
00:40:00reported as being made a number of times in the early literature, but the
circumstances were not too clear cut. In 1933 [Otto] Ruff had reported making
TFE by decomposing CF4 in an electric arc. He took the
crude TFE that was produced and reacted it with bromine to get the
dibromotetra-fluoroethane compound. Then he pulled the bromine out with zinc in
ethanol and got a purified TFE. He characterized the compound and determined
some of the physical properties.
A year or so later Henne reported pulling Cl2 out of tetrafluorodichloroethane
00:41:00in a similar manner. I decided to try to make the
compound tetrafluorochloroethane by making some TFE and then adding HCl to it. I
chose to make the TFE by pulling the chlorine out of the
tetrafluorodichloroethane. I was ambitious and decided to make one hundred
pounds of the material. I did set up the apparatus and did convert the material
to about one hundred pounds of TFE and then purified it in the laboratory by
distillation. I stored it in small cylinders in a dry ice chamber and set it
aside to use later to make the proposed refrigerant.
00:42:00BOHNING: Why did you select one hundred pounds? Was there any reason you made
such a large amount of it at the beginning?
PLUNKETT: We wanted to have enough to evaluate it as a refrigerant and to
evaluate it thoroughly toxicologically for its effect on animals. So it just
seemed like a round number.
BOHNING: You stored this in small cylinders?
BOHNING: You must have had a huge collection of cylinders.
PLUNKETT: Yes, I had quite a few. I set the limit at one to two pounds per
cylinder so there were about fifty cylinders. I scrounged bug-bomb type
cylinders and small cylinders of all kinds. I rinsed them out and used them to
store my TFE.
BOHNING: They were all kept at low temperatures?
PLUNKETT: Yes, at dry ice temperature.
00:43:00BOHNING: What happened on April 6, 1938?
PLUNKETT: After having made the TFE, I then had to set up a laboratory apparatus
to add HCl to the TFE. I would put the cylinder of TFE on a scale and vaporize
the TFE through a metering device into a electric-heated carbon-bed catalyst
tube reactor. At the same time I was leading from another system a stream of HCl
which I generated. That was the way I was making the tetrafluorochloroethane.
On the morning of April 6, 1938, after having selected one of the cylinders we
had been using previously, my helper said, "Hey Doc, did we use all of the gas
00:44:00in this cylinder?" And I said, "No, I don't think so." He said, "Well, nothing's
coming out. I don't know what the heck is wrong." On further examination it was
quite evident that there was material in the cylinder but there was no gas pressure.
BOHNING: That was from the weight of the cylinder?
PLUNKETT: Right. From the weight, there was still material in the cylinder but
there was no pressure and the valve was completely open. No gas would come out.
On further checking, we actually opened up the cylinder and let a wire down
through the valve to be sure there was no gas pressure. Later, we took the valve
out of the cylinder and shook out some powder which proved to be the first
evidence of a polymer of TFE.
00:45:00BOHNING: How did you conclude that polymerization had taken place? Were you
aware of polymerization as a chemical phenomenon?
PLUNKETT: I was familiar with the fact that monomers do polymerize and you make
polymers out of polymerizing monomers. I was not aware that TFE would
polymerize. As a matter of fact, I think the teaching of that time would be that
no fully halogenated ethylene molecule would polymerize. This was like a
proverbial bumblebee. It didn't know it couldn't polymerize and went right ahead
and did so. Somebody asked me in the past, "What was your reaction?" My reaction
was, "Well, we have to start over now. Particularly if all of this other stuff
has polymerized like this."
00:46:00BOHNING: You had made a large amount of HCl addition product before this
particular incident happened. So this wasn't the first cylinder that you used.
PLUNKETT: This wasn't the first one. How many cylinders we had used is a hazy
memory now. I don't know how many we had. I know we had made a fair amount of
the proposed refrigerant and we still had a lot of cylinders of TFE left.
BOHNING: You also mentioned your helper. What was his name?
PLUNKETT: His name was Jack Rebok. He was a local, southern New Jersey boy from
Paulsboro, New Jersey who came to work with Du Pont after he finished high school.
BOHNING: Did he have any reaction when this occurred?
PLUNKETT: His reaction was, "What the hell is going on, Doc?" And he thought the
same thing I did. "Well, we're going to have to start all over. We're going to
have to make this stuff."
00:47:00BOHNING: When did you realize that that white powder had unusual properties?
PLUNKETT: Not right away because all I could see was the powder. I soon started
to examine some of it to see whether I could dissolve it in something. I
couldn't find anything in the laboratory that would dissolve it at all in any
shape or form. It didn't react with anything. There were no chemical reactions
that I could determine so those facts themselves said that there was something
unusual about this material.
BOHNING: Did you do that the same day?
PLUNKETT: I did some of it the same day.
BOHNING: Did you eventually work your way through the rest of the cylinders to
see what they contained?
PLUNKETT: Well, I don't remember how many cylinders were cut open but there was
a substantial number.
00:48:00BOHNING: Certainly more than one.
BOHNING: Probably even more than two or three?
BOHNING: In terms of the patents you've had, the Teflon patent didn't come until
1941 and the others came in 1946 and later.
PLUNKETT: Right. After having found out that the TFE does polymerize, one of the
things I set about to do soon thereafter was to make TFE polymerize. I did set
up some experiments in which TFE was put into glass tubes without any designated
catalyst, with potential catalysts, and with a solvent. Under all conditions I
00:49:00did get some polymerization. Those studies provided the basis for the patent
claims on the original patent of PTFE as a composition of matter and how to
BOHNING: But the other processes came later. You filed for a patent in 1939 and
it was granted in early 1941. You also had patents on the preparation of TFE and
on the CHF2-CClF2, but they came after the war.
PLUNKETT: Right. They came afterwards because they got caught in the Patent
Office secrecy order to cover up all the work on fluorine chemistry.
00:50:00BOHNING: This probably comes a little bit later but I wanted to ask it now. You
refer to it as PTFE. When did the name Teflon come into existence?
PLUNKETT: The Teflon name for PTFE resin was coined in 1944.
BOHNING: Oh, that much later. Were commercial uses coming into being at that time?
PLUNKETT: That was still 1944 and we were still under wartime secrecy. Du Pont
had made some evaluations of potential uses. Maybe we should back up a little
bit. The next question was, "What are you going to do with this stuff?" I didn't
00:51:00know much about what to do. I didn't know anything about polymer chemistry
itself but I was fortunate to be with the Du Pont Company who had a lot of
chemists and engineers doing work in polymer fields. So we asked some of our
associates in the Central Research Department to take some of this powder and
see if they could mold it in some way and characterize it a bit. They did, using
powder metallurgical techniques. They compressed the powder under pressure and
temperature in a mold, and did do some molding. By examination of that we
00:52:00started to get some physical properties. This led of course to examinations and
postulations of what could be done with it, what it would take to manufacture
it, and what it was going to cost. Those deliberations at that point in time
weren't too encouraging. This stuff was going to cost so much that nobody was
ever going to buy it.
BOHNING: Were those decisions made by marketing people?
PLUNKETT: I don't know whether the marketing people had gotten into it at that
time or not. There were probably deliberations only by research people at that
00:53:00time. But, then we came to the time when the country formed the Manhattan
Project. The Manhattan Project people began to study ways and means to separate
uranium isotopes and found out that they wanted to make fluorides of uranium and
try to separate them that way. They recognized that they were going to need a
lot of materials. Du Pont reviewed this with some of the Manhattan Project
people. When General [Leslie] Groves, who was director of the Manhattan Project,
heard about this new plastic material, he said, "That sounds like something
we're going to need. You had better get a hold of it and develop it or we're
going to take it away from you." That was about the way it was. [laughter]
00:54:00And so with that encouragement, and with the interest of Du Pont people, work
was stepped up on the fundamental studies and to develop some techniques that
could at least be a basis for a pilot plant. In the early 1940s there actually
were pilot plants set up to make TFE, to polymerize TFE, and to mold and
fabricate PTFE. All three separate strings were coming together. This work was
going on while they were making stuff. I think one of the Du Pont men was
00:55:00talking this morning about Du Pont's experience in fluorochemicals and said all
of it that was made during the whole war period wasn't very much. But a lot of
it got used by the military and by the Manhattan Project. I'm sure that Du Pont
had opportunities to evaluate it for some of their own uses at that time.
There is one point I can relate to you. At the Chambers Works they had a dye
process that involved nitrations with seventy percent fuming nitric acid. This
00:56:00mixture had to be pumped and it was a very corrosive operation. The pump failed
at least once a week and had to be torn down and rebuilt. One of the early tests
of Teflon was to pack this pump and valves with Teflon packing. It ran so well
that six months later, as I remember the story, it was decided to tear down the
pump assembly to see how it had stood up. It was torn down and everything was
still working alright. So there had been some cases where it might be too
expensive, but here was a case in point where it was cheap at any price.
00:57:00BOHNING: Does your original laboratory notebook still exist?
PLUNKETT: My original notebook which records my observations of the day that
PTFE was discovered does exist. It's in the hands of Du Pont and recently some
of the Du Pont European people made some copies of this two page spread and blew
them up and asked me to sign numerous copies of them. If you talk to Lana Kirch
maybe you could get a copy.
BOHNING: We'll have to see if we can get a hold of one. That would be excellent
00:58:00There are a number of things that are curious to me after this event occurred in
April of 1938. Your involvement changed rather quickly.
PLUNKETT: My involvement changed within a very short period of time. This had
nothing to do with what I wanted to do or what I might not want to do or what
somebody else wanted to do. There was another fellow that was working on
tetraethyl lead research and was getting a promotion. They took him out of doing
direct laboratory work to be assistant director of the laboratory. They needed
somebody to pursue that tetraethyl lead work. I was chosen to do that. So within
00:59:00months after the discovery I was transferred into doing tetraethyl lead work. I
know it was within months because on January 1 of 1939 I was transferred from
the laboratory to the tetraethyl lead manufacturing organization as chief chemist.
BOHNING: What was your position before that?
PLUNKETT: Research chemist.
BOHNING: In the Jackson Laboratories?
PLUNKETT: Yes. I was a research chemist assigned to fluorine and a research
chemist assigned to lead and then I got transferred from the research
organization to the manufacturing organization in tetraethyl lead.
BOHNING: You were with the tetraethyl lead plant from 1939 to 1949?
01:00:00PLUNKETT: Right. In 1939 when I was transferred to the tetraethyl lead
organization the use of antiknock compounds were expanding rapidly and continued
to do so for the next year or two.
01:01:00[END OF AUDIO FILE 1.2]
PLUNKETT: Then along came Pearl Harbor and the U.S. involvement in World War II.
One of the first things that happened was that the government stopped the
manufacture of automobiles. Stopping the manufacture of automobiles stopped the
demand for tetraethyl lead. We in the operations group that was making
01:02:00tetraethyl lead were faced with what to do. What we did was to convert our
facilities from making tetraethyl lead to making one of the synthetic rubbers.
We developed a process for making synthetic rubber using our tetraethyl
equipment. We just got to the point where we had a conversion and were starting
to make synthetic rubber when Roosevelt said we're going to build millions of
airplanes -- warplanes! Then all hell broke loose. [laughter] We had to get back
into making tetraethyl lead! [laughter]
BOHNING: How long were you involved with synthetic rubber before you moved back?
PLUNKETT: About a year or a year and a half.
BOHNING: What was your function in that process?
01:03:00PLUNKETT: In the tetraethyl lead organization I was the chief chemist. We were
just all given the job of converting to rubber manufacturing, and I kept the
BOHNING: Were you actually involved in the manufacturing process?
PLUNKETT: I was involved in developing the manufacturing process and the
conversion process. Actually we were working with one of the Thiokol rubbers. We
met with the Thiokol people and got their process information which we tried to
transmit to fit the kind of apparatus we had.
BOHNING: I notice you have three patents on tetraethyl lead.
01:04:00[recording runs while Bohning and Plunkett look over patent documents]
PLUNKETT: Yes, I have some patents on tetraethyl lead. They were on methods of
improving the yield of tetraethyl lead in the manufacturing process during the
reaction of ethyl chloride with lead monosodium alloy.
BOHNING: It's not clear in my mind what you did after 1945.
PLUNKETT: In 1945, which was approaching the end of the war period, we had an
01:06:00organizational upheaval in the tetraethyl lead groups. The head man (the
superintendent) and the second head man (the chief supervisor) were removed.
They picked up Plunkett and said, "You're boss." So I got promoted to being
superintendent of the tetraethyl lead area in early 1945. I had that position
until 1949 at which time I was transferred to a similar position. I was made the
superintendent of the plant producing vat dyes.
BOHNING: It was the Ponsol colors area. What does the word Ponsol mean?
PLUNKETT: Ponsol was a part of a trademark for vat dyes.
01:07:00BOHNING: So in that 1945-1949 period, I can imagine TEL [tetraethyl lead] became
very important again.
PLUNKETT: TEL became very important again. Until then, Du Pont and Ethyl
Corporation had a manufacturing and service agreement type of arrangement. Then
in the period of time we're talking about Du Pont and Ethyl Corporation split.
Du Pont went out to manufacture and sell tetraethyl lead on their own and Ethyl
Corporation went out to manufacture and sell tetraethyl lead on their own. I was
deeply involved in working out the details of that schism because we had a
manufacturing plant at Chambers Works and one that we were operating for Ethyl
01:08:00Corporation in Baton Rouge, Louisiana. I spent half of my time on the train
going back and forth to Baton Rouge for several years.
BOHNING: Now with the dye area...
PLUNKETT: I was transferred in the latter part of 1949 into this dye operation
as superintendent over the top of everyone else who was there. I was a bad boy,
and I was resented. I only stayed there nine months. In June of 1950 I got
promoted to assistant plant manager of the Chambers Works. All of the resentment
01:09:00that I felt when I moved into that dye business was gone by that time.
BOHNING: Do you think that resentment was in part due to your association with Teflon?
PLUNKETT: At that point in time it wasn't that clear that I was associated with
the development of Teflon. It hadn't yet become too widely known. The first
public recognition that I received as inventor of Teflon was in 1951 when I was
awarded the John Scott Medal by the city of Philadelphia. That was in 1951 but I
01:10:00didn't receive the medal until June of 1952. Du Pont had several hundred people
come to a banquet at a country club in Penns Grove, New Jersey. I was presented
with the John Scott Medal and they had a big to-do. Professor [Hubert N.] Alyea
from Princeton came down and talked about it. He eulogized my work. That was the
first public recognition of many. Also, it was the first time that anybody in
this country saw any cooking utensils lined with Teflon. They made muffin tins
01:11:00lined with Teflon and gave them out as favors to all the attendees of this
banquet. Some of those muffin tins are still in existence. I have one of them at home.
BOHNING: In talking about this as the first public recognition that you had, how
did the company react? It must have taken some time before the full impact of
what you had done was recognized.
PLUNKETT: I think it did take quite awhile. Of course, it didn't amount to
anything financially to Du Pont until probably 1950. Maybe later because during
its early stages it was costing them a hell of a lot more to produce it than
01:12:00they were getting for it. Even though they were selling it for twenty-five
dollars a pound or something like that and even though little gasket companies
like the U.S. Gasket Company in Camden, New Jersey had the Teflon delivered to
their bank vault in Camden. If they wanted to use some, they had to go over to
the bank to get it. [laughter] That's an absolute true story.
BOHNING: Do you think the company eventually recognized you properly?
PLUNKETT: Oh the company recognized me. There's no question in [Edward G.]
01:13:00Jefferson's mind who's responsible for Teflon. I hadn't seen Ed for several
years until after I retired down at Corpus Christi in 1983, which was the tenth
anniversary of the set-up of the Corpus Christi plant. Ed was down there to give
a talk. I had seen him just shortly before the talk. Ed used the occasion to
recognize me and eulogize me right there on the spot.
BOHNING: That's wonderful.
PLUNKETT: Last year when I got notification that I had been nominated for the
Inventor's Hall of Fame, I got a call from the senior vice president of the
01:14:00Central Research Department. He called and told me that Ed [Jefferson] had asked
him to call me. A day or two later I got a letter from Ed telling me about about
this. This was in early December of 1984. In early January of 1985, I got a call
from the Public Affairs Department. Lois was home and I was on the golf course.
They told her, "Well, have him call. How would he like to have a vacation in
Delaware?" She said, "What, in January?" [laughter]
01:15:00I did go that next week and they had been commissioned to see that I was
properly recognized. I came up there and spent a whole day talking to a group of
people and spent a day in the photo shop and things like that. When it came to
the time of the presentation of the award, the inductees were feted at a banquet
on Saturday night and the award presentation took place on Sunday afternoon.
I was called to Wilmington several days ahead of this presentation and they had
the public relations group from Philadelphia to come and spend almost a day
01:16:00interviewing me. Then I spent more time with the photographers. Then I went to
Washington. There was a public relations outfit down there to set up interviews
with me from all of the TV, radio, newspapers, and magazines. I was in
Washington from Friday until Tuesday evening and I was constantly in a Mercedes
limo being pushed from one place to the other. Du Pont had a press breakfast on
01:17:00Tuesday morning following the presentation of the award, to which they had
invited a lot of people to come. It was a big press breakfast they had set up in
my honor. They had a big banner up, "A New Name in the Hall of Fame," and they
had several of the Du Pont people including the head of the Central Research
Department. They had somebody from Bell Laboratories and the engineer in charge
of restoring the Statue of Liberty, and several others. I got up and said a few words.
01:18:00On Monday morning there was an article in the Washington Post and it seemed the
White House saw this article in the Washington Post which was about me and some
others, but this story was mainly about me. The President was having a luncheon
on Tuesday of one hundred scientists and engineers and he said, "Get these guys
here." So I had lunch with the president on Tuesday.
But on Sunday, after I got the award, the first thing I did was to get in an
airplane and fly to New York to appear on the Today show on Monday morning and
01:19:00be interviewed by Jane Pauley and fly back to Washington before noon. I think
they recognized me.
BOHNING: The reason behind that original question was that the company itself
took awhile to realize the impact of the work.
PLUNKETT: Oh, yes. There was no question that I was a god, because if you have a
list of the Teflon patents, it's the most widely patented material the Du Pont
company ever had by far. Through the years, I was continually being called up to
sign a patent application. Every time it was patented in a new country, I had to
sign another patent application. There was no question about who made the
01:20:00discovery. Whether I was naïve or whatever -- I made the discovery and I knew
what I had chemically. I didn't know all it was valued for but I had made the
discovery. I say sometimes when I talk to high school kids -- I've done that a
number of times -- one of the things you go to school for is to learn how to
think. You have to have a prepared mind when you get into situations like this.
And I think I had a prepared mind.
BOHNING: I am intrigued by the fact that you worked very quickly on the
01:21:00properties and were able to determine exactly how unusual this material was. The
next step then was to perfect the production of the polymer.
PLUNKETT: It was to demonstrate that I could make something.
BOHNING: So then you had a way of doing it routinely.
PLUNKETT: At least I had a basis for a patent. I don't know if I had a basis for
a routine. Some other people got in to do that. But I did immediately do
something to try to find out what it was.
BOHNING: Let's go back to 1940.
01:22:00PLUNKETT: The Manhattan District work gave the impetus to develop the processes
for making and handling and fabricating Teflon. That work was successful and
they found a lot of military applications and numerous applications in the
chemical processes in connection with the Manhattan Project. One of the first
military uses was in the nose cone for proximity fuses on proximity bombs. It
would transmit the radio waves for awhile. That was one of the first uses. But
it got a lot of uses, even in the early days, in electrical and electronic
applications. Of course those are the greatest users today. The
01:23:00tele-communications field is the single greatest application of Teflon even
today. At the end of World War II, patent secrecy was lifted, and at the end of
1946, there were publications and patents granted. There were about thirty
patents granted in 1946 related to Teflon materials.
BOHNING: Were these all Du Pont patents?
PLUNKETT: I think that I'm talking only about Du Pont now. No, I doubt that
there were because Du Pont had apparently gotten some other people working on it
01:24:00by that time. It's one of the things about it because there's been many chemists
and engineers and entrepreneurs that have contributed to the development of
Teflon and PTFE and all of its uses. But in 1946, the Du Pont Experimental
Station people put out a paper in which they described some of the work done
during World War II. The Plastics Department people
put out a paper in Industrial and Engineering Chemistry in which they described
the processing applications. There had to be lots of
inventions just to learn how to handle the damn stuff. One of the things was a
01:25:00ram extrusion press in which you feed the powder in through a bin and compress
it in a heated zone and come out with a rod or tube or something. It was
processing Teflon under controlled conditions. They would come out with little
rods to big tubes to great big batches of the stuff. Obviously, it took an awful
lot of work and people to develop it.
BOHNING: Who were some of the people that worked in the area after you left it,
that picked up where you left off?
PLUNKETT: Butch [William E.] Hanford and Bob [Robert M.] Joyce were two people
that did work in the early 1940s in the Central Research Department and they
01:26:00published the 1946 paper.
BOHNING:: Was their work mostly characterization?
PLUNKETT: Their work was process work for methods of polymerization. They
developed the basis for the emulsion polymerization process and they
characterized the polymer. They did some of the early characterization work.
Then in the Plastics Department, there was Malcolm Renfrew.
BOHNING: I talked to him just yesterday.
PLUNKETT: You did?
BOHNING: Yes. He's here for the ACS meeting.
01:27:00PLUNKETT: Yes. He and [Ernest E.] Lewis were both at Arlington at the time and
they did a lot of the work in connection with developing techniques of handling
BOHNING: I didn't realize Malcolm was involved. What years would that have been?
PLUNKETT: The early 1940s, because the paper was published in 1946. It was after
the secrecy was lifted. Then of course the process for making TFE from the
pyrolysis of CHClF2. That was developed and perfected by the people at Jackson
01:28:00Laboratory, [Anthony F.] Benning and [Robert C.] McHarness.
BOHNING: Did you keep up with what was going on in Teflon while you were over in TEL?
PLUNKETT: I didn't keep up as much as I might have because I was not in on the
secrecy of the Manhattan Project work. I knew the Manhattan Project was going on
because we had the pilot plants there in the Chambers Works, right next door. I
was aware that the work was going on but I was not part of it. I was one of the
01:29:00first guys that was called after the bomb was dropped in 1945. I got a call from
one of my bosses who said that they just dropped a bomb on Hiroshima.
I have a couple of paragraphs in my talk which indicate that from stove tops to
outer space, from electronics to ecology, from architecture to the Statue of
01:30:00Liberty, Teflon touches everyone of us some way almost every day and it is an
integral part of all of the things that makes the machinery of commerce work today.
Then I want to add one more thing at the end. It's been exciting to be a part of
this thing, to have a part in it and to know that it's been a benefit to real
people, not just to imaginary people but real people that I know. Several years
ago, I attended a dance near Wilmington and a doctor friend of mine said, "Roy,
I want you to meet somebody here. See that gentleman out here dancing. He's here
01:31:00dancing only because he's wearing a Teflon aorta which I installed." So I add to
that, that over the years I've experienced or heard of many instances like that
and it makes me realize that I've been more than just helpful.
[END OF AUDIO FILE 1.3]
BOHNING: How do you view today what occurred back on April 6, 1938? You
01:32:00essentially answered your reaction to that. I'm sure you couldn't imagine at
that time what was going to come in the future but you evidently had some idea
that this was something very important that was going to develop.
PLUNKETT: In a certain period of time I realized that it had potential and I've
indicated that there were times when there were doubts over the economics of it.
That certainly has been proven out again and again.
BOHNING: Did you have trouble convincing anyone of what had occurred then?
PLUNKETT: No I don't think I had any problem convincing anybody of what had
01:33:00taken place. I knew what had taken place and I think they knew.
BOHNING: How did your colleagues react to that when they heard the news?
PLUNKETT: It's too hazy in my mind. I don't know what happened there. It took
quite awhile before there was anything significant.
BOHNING: We left off at 1952 when you moved to the Organic Chemicals Department.
PLUNKETT: Oh, yes. In 1950 I became assistant manager of the Chambers Works. I
01:34:00spent a year and a half in that position. In January of 1952 I was transferred
to Wilmington as manager of the plants chemical section for the Organic
Chemicals Department. I had charge of the chemical development on all of the
organic chemicals department plants. A little bit later I became assistant
manager of the plants technical group which put engineering and chemistry
together and later I was manager of the plants technical organization. That
01:35:00lasted until about 1960 when the Organic Chemicals Department had a major change
in organization. They divided the businesses into several business groups. One
of them was the Freon business group. There was a business director. I became
director of research for the Freon Products Division in 1960. I spent ten years
in that position.
BOHNING: You were almost coming back to where you had been at the beginning.
PLUNKETT: Right. During that period from 1960 to 1970, my staff and I developed
some new processes for large scale production and integration of the
manufacturing of Freon products and formed the basis for establishing the plant
01:36:00in Corpus Christi, Texas. In 1970 I was moved out of research and was given the
job of director of operations. The main job was to get that plant into being.
BOHNING: That explains why you're in Texas now. [laughter]
PLUNKETT: That explains how I got to Texas. [laughter]
BOHNING: I had wondered about that. I remember people talking about your
retiring to Florida. I wondered how you had arrived at Texas.
PLUNKETT: I probably would have ended up in Florida if it hadn't been for Texas.
I fell in love with Texas when I became acquainted with the people. Of course I
was in Wilmington all of the time. I was not personally down there, but I was in
charge of the plant. I went back and forth to Texas once a month for five years
01:37:00and I got kind of familiar with how to get there.
BOHNING: I have read somewhere that you are quite a collector of antiques.
PLUNKETT: I did do quite a bit of collecting of antiques back in the 1950s and
earlier. I did a lot of restoration. My previous wife and I did collect
antiques. I did furniture restoration and bought an old house. It was one of the
taverns on the King's Highway in southern New Jersey. I spent a little time
there. Lois and I have some antiques now but we're not doing as much as I did earlier.
01:38:00BOHNING: I also understand that you have two sons.
PLUNKETT: Yes. Michael will be forty-five this fall. He is a technical
representative for Du Pont's carpet fibers and works out of the Charlotte office
for the Textile Fibers Department. He apparently is a very much respected person
in his field. At least he's still being sent to a lot of meetings and is pretty
01:39:00effective in the carpet fiber sales business.
My other son, Patrick, will be forty-two this fall. He is sort of a renegade. He
was always pretty lazy but pretty smart. He came back from Vietnam in 1969 and
said, "Dad, I'm going to be a ski bum for a year." And that lasted about eight
years. I guess he was a pretty good ski bum. He's located in Washington, D.C.
01:40:00now and is a computer software consultant. He and two or three other fellows
have formed a little company which they call Internet. The name almost tells you
what it is. They're doing network studies for connecting computers. He just
recently got married and is looking forward to raising a family.
BOHNING: One of the reasons I asked a question like that is curiosity about
whether they may have followed you scientifically.
PLUNKETT: Neither one of them did. Michael came closer. He got a degree in
mechanical engineering but somewhere along the line the magic left him. They had
01:41:00an interest in the early days when they were small. "Daddy, that's what I want
to do. I want to become a chemist." In the early days Patrick had a little
chemistry set. In 1955 when the boys were about fourteen and eleven, and I was
away in Trinidad, they blew up that chemistry set. Both of them went into the
hospital. The younger one had a piece of shrapnel that went through his forearm
and severed off the artery. It's still severed. My other son, who was closer to
01:42:00the set, got burns on both eyes but he didn't lose any sight. So, I don't know
whether that pushed them away from science or not.
BOHNING: It's amazing that there are a number of people with established careers
in polymer science whose children never went into chemistry.
Is there anything else that you would like to add at this point that we haven't
talked about? We've primarily concentrated on the early period.
PLUNKETT: I think that that pretty well covers it. I can relate to you a couple
01:43:00of instances. I mentioned earlier that during the years I've gotten a lot of
honors. Do you have one of my bio write-ups?
BOHNING: Yes, I have some information, but it's back in Philadelphia.
PLUNKETT: Did that come from Du Pont?
PLUNKETT: I've received a whole array of various types of honors -- Modern
Pioneer in American Industry, Modern Pioneer in the Institute of Chemists.
They're all recorded in this bio-script. I've gotten three honorary D.Sc.
01:44:00degrees. The first one I got from Manchester College in 1952. The second one I
got from Washington College in Maryland in 1968. The last one I got from Ohio
State in 1977. And after that one, until I got the National Inventor's Hall of
Fame, I thought I had arrived. [laughter] Somebody said to me at the time of my
induction into the Inventor's Hall of Fame, "What do you think about this?" I
said, "Well, I don't know. I'm riding on cloud nine but I wonder what the hell a
little old country boy from Ohio is doing in this crowd."
BOHNING: Well, there were a lot of people with similar backgrounds. Paul Flory
is one example. Harold Urey was a country boy from Indiana.
01:45:00PLUNKETT: Jane Pauley said, "Well, Edison was a country boy." [laughter] When
she shook hands with me when I finished my interview with her she said, "I think
Edison is in good company."
BOHNING: When did that interview take place?
PLUNKETT: February 11 in 1985.
BOHNING: We might see if we can get a hold of a copy.
PLUNKETT: I think Lana Kirch may be able to get you a tape of that. A public
01:46:00relations firm in Philadelphia were the ones who arranged it.
BOHNING: I guess that brings us to a close. Again, I would like to thank you
very much for taking the time to chat with me this afternoon.
PLUNKETT: I'm happy to cooperate, Jim. It's important to do these things.
[END OF AUDIO FILE 1.4]
01:47:00BOHNING: Dr. Plunkett, I want to thank you again for agreeing to spend some time
with me this morning. In reviewing the transcript of the talk we had in New
York, one of the areas I want to go back and perhaps get a little more
information on is your association with Paul Flory. When did you first meet Paul Flory?
PLUNKETT: I first met Paul Flory when we entered Manchester College in the fall
BOHNING: I believe you mentioned that his parents and your parents knew each other.
PLUNKETT: That is not true. My family were members of the Church of the Brethren
01:48:00and Paul's father was a minister in the Church of the Brethren. Paul's uncle was
also a minister in the Church of the Brethren and he was the minister for a
period of time at the church that my family attended in Ohio.
BOHNING: But you never met him before you went to Manchester?
PLUNKETT: No. The other Flory had a son who went to Manchester at the same time.
So Paul and his first cousin were at Manchester at the same time.
BOHNING: Do you remember the names of the cousin and the other minister?
PLUNKETT: The cousin's name was John. I don't remember his father's name.
BOHNING: I think you said that you and Flory also roomed together when you were
01:49:00PLUNKETT: I think that Paul and I roomed together in the third year that I was
at Manchester. He and I and two other fellows roomed together. We had the
upstairs of a nearby house that was a certified rooming house for the college.
We roomed together that year which was the last year that he was at the college.
It was my third year. He got ahead by going to summer school and finished up the
following summer. He then went on to the university. I was out what would have
been my fourth year because my father was ill and I had to run the farm.
BOHNING: I see. Let me go back to your first meeting with Flory. I assume you
01:50:00took the same classes together. Did you both come in as chemistry majors?
PLUNKETT: When we came in to the college I don't know that we decided that we
were going to be chemistry majors. But it so happened that we did essentially
take the same classes the first year and the second year.
BOHNING: Did you socialize at all during that time or was your contact mainly
PLUNKETT: It was a small college. The student body was not more than about six
hundred at that time. That means the freshmen class was probably two hundred. It
drifted down a bit toward the senior class so that you pretty well got to know
everybody. Yes, we did socialize in college functions.
BOHNING: What about during the summers when you were back home?
PLUNKETT: He lived in Illinois and I lived in Ohio but I remember one summer.
01:51:00This was after college because we both went together to the World's Fair in
Chicago. I believe it was the summer of 1933. That was after we had both graduated.
BOHNING: Could you tell me something about Flory in terms of how you remember
him as a student? What he was like as a student in the classes you attended?
PLUNKETT: I always recognized Paul as being a very smart fellow. He knew what he
was doing, where he was going, and he was always at the lead of any group that
01:52:00he was associated with. I tried to keep up with him but I couldn't quite do
that. He not only exhibited that he always wanted to be at the top -- he was
always there. I'm sure that he always had the urge to be there. It was always my
goal. I didn't like to be second best. I never was always best, but I didn't
like to be second best. I think Paul inspired everybody he worked and associated
with. He was recognized as a leader in whatever way. This sometimes carried over
to mischief too. So on mischief nights such as Halloween, he would get into
01:53:00mischief and he was a good leader for mischief too. [laughter]
BOHNING: Are there any specific examples that you care to share?
PLUNKETT: I'll share one. One Halloween, we found an old horse-drawn milk wagon
that was a mile or so from the college. Paul and I and a few other fellows -- I
don't specifically remember who they were -- decided that we were going to get
that milk wagon and take it into the auditorium and set it up on the stage. And
we did that. Halloween night we went to bed and set our alarms for about one
o'clock, got up, went out and got the milk wagon, and pushed it up to the
01:54:00administration building. We got the side doors open to the auditorium, took the
wheels off the wagon, carried the body into the auditorium, put it up on stage,
and then put the wheels back on. Then we went home and went back to bed. [laughter]
Part of our glee was taken out of it though because when we got up the next
morning, the president had found it, got somebody else to take it out and we
couldn't tell anybody. [laughter]
BOHNING: How did the faculty at Manchester respond to him?
PLUNKETT: I think by and large he got A's in practically all of his classes --
not all of them. The dean of the college and the head of the chemistry
01:55:00department responded to him very much because as he got interested in chemistry,
the dean encouraged him to try a few things. He had him doing experiments, I
believe, at the beginning of his third year. He just inspired everybody. He was
proper. He was not a braggart but he also wasn't too modest. We knew he was
there. I remember one time when I gave a talk at Cornell. I was talking to him
afterwards and he said, "Don't be so damn modest." [laughter]
01:56:00BOHNING: Let me back up a moment. Had he focused on chemistry early or do you
know if he was considering other possibilities at Manchester?
PLUNKETT: I'm not sure. He finished up his third year at Manchester in 1930. He
had enough to qualify for his degree so that he went to university in the fall
of 1930. By that time he had certainly settled on chemistry. He then went right
straight through at Ohio State and I think he got his Ph.D. in 1934.
01:57:00BOHNING: When he went to Ohio State you were still at Manchester.
PLUNKETT: I was still at Manchester but I had two things happen to me. He got
out a year early and I lost a year because of taking care of my family. So, it
was two years later when I got through. I got out in 1932 and I went to Ohio
State in the fall of 1932. Paul was pretty well established at that time in
doing his doctorate research. I don't know what year it was but he was a Du Pont
fellow at Ohio State.
BOHNING: Did you have any contact with him during that two year period?
01:58:00PLUNKETT: Yes. We occasionally met at social affairs. He was a member of the
Gamma Alpha society and so was I. I think we both lived at the house part of the time.
BOHNING: What about the time that he was at Ohio State and you were not? That
two year period between 1930 and 1932.
PLUNKETT: I don't remember specifically about there being any contact because
usually the summer periods evolved from the winter and whatever we did in the
summer got planned in the winter. So, I don't recall much activity during that
period of time. Anyway, I was pretty busy running my dad's farm for about
01:59:00BOHNING: You said you lived in the Gamma Alpha house together.
PLUNKETT: Yes, we lived in the Gamma Alpha house and we sometimes went to
parties that involved girls. I got married after he was gone. I believe that I
lived in the Gamma Alpha house and he did too during the last year that we were
BOHNING: Did you keep in contact with him over the years?
PLUNKETT: Yes. He came to Wilmington when he went to work with Du Pont in late
02:00:001934. I came to Wilmington to work at Du Pont in 1936. During the time that we
were both there, we frequently met on social occasions. We didn't have any
direct connection workwise. He was working with Carothers in the Experimental
Station. I was working in Jackson Laboratory and the twain seldom met so that I
didn't see him directly at work. But we did meet at parties. I forget just when
he and Emily got married but it was sometime during that period of time. We
would have some visits house to house. He left Du Pont and went to Exxon first,
I believe. Then he went to one of the rubber companies. He went to the
02:01:00University of Cincinnati to teach for awhile. He had another industrial
connection and then he went to Cornell. He then went from Cornell to Mellon
Institute and from there to Stanford. Those were essentially the movements that
he made in his career.
I kept in touch every year all the time at Christmas time. During that whole
period of time there was at least an exchange at Christmas time. I would quite
frequently write him a note if I saw something that had been recognized of his
and occasionally got one from him. Several years ago he gave the Franklin Medal
talk at the Franklin Institute. When he came to give that talk I received an
invitation at the suggestion of Dr. Flory.
02:02:00BOHNING: I think you also said that you were at the Priestley House in 1974.
PLUNKETT: Yes, when he gave the Priestley Award lecture out at Priestley's home.
Actually he gave the address at a place nearby, but received the award at the
house. There were quite a few of us who drove up there that were former
associates. Don Martin, who had been a student of Holl's and a teacher at
Manchester, was at the time located in the Wilmington area and associated with
02:03:00Hercules. He and I and one or two others and I believe his son-in-law was with
us. His daughter married a man who turned out to be a chemist and worked for
Hercules. Right now I can't think of his name. But we went there and I think we
spent the night. It was a late night program.
BOHNING: Yes. The dinner was late in the evening. Did you have a chance to talk
to him then?
PLUNKETT: Yes, but not much. He was pretty busy. I had a chance to chat with him
and congratulate him. I saw him most often for a period of years after he went
02:04:00to Stanford. I would frequently in my capacity as a research director at Jackson
Laboratory have the opportunity to visit several of the California schools.
Usually when I visited Stanford, I would have dinner with Paul and Emily and
sometimes stay the night with them. So we would keep in contact that way.
In the fall of 1981, Washington College in Chestertown, Maryland had a two
hundredth anniversary and they had a day called "Two Hundred Years of
Chemistry." They invited a number of people there. Flory was invited and I was
invited. Part of that came about because one of the prominent members of the
02:05:00Board of Governors of Washington College was a man by the name of Phillip
Wingate who retired as a Du Pont vice president. He was a graduate of Washington
College and knew both Paul and me as associates because he started with Du Pont
at about the same period of time that we did. He had earlier been instrumental
in seeing that I got an honorary doctorate from Washington College. So he helped
put together the invitation list for this two hundred year anniversary. We got
to visit with Paul and Emily and had a special dinner at the house of the
02:06:00president of the college. That's the last time that Paul and Emily and Lois and
I were together.
BOHNING: I think that information is very helpful in filling in some more of
your association with Paul Flory. What I would like to do now is move to 1938 to
the Teflon work and ask you a few additional questions. Let me ask you about
Jack Rebok who was your lab assistant. How long had he been with the company?
PLUNKETT: All I can say, Jim, is several years. I don't know know that I ever
knew exactly when he started work. He was a top notch technician when I got
there in 1936.
02:07:00BOHNING: What was his background?
PLUNKETT: He was a local born and raised from Paulsboro, New Jersey. He lived at
Paulsboro when he retired and I think he still lives there. Paulsboro is just
across the river down there. Whatever training he got was mostly by osmosis with
people he worked with.
BOHNING: Was he assigned to you specifically?
PLUNKETT: At the time he was my helper on this project.
BOHNING: What kind of scientific reading were you doing at that time?
PLUNKETT: At that time I received the Journal of the American Chemical Society.
02:08:00I received Industrial Engineering Chemistry. I received Science and of course
the ACS news magazine. I read those pretty regularly in those early days. I
didn't read them as much in later years. I would read special things that came
along but I don't think there's anything else that I can say that I read
regularly. Well, for awhile I read the English magazine Nature that was similar
02:09:00to Science. I was reading that at the time. Other than that, my reading was what
I was looking up in the library that was connected with my work.
BOHNING: Did you select the target molecule that you were trying to make as a
PLUNKETT: I don't know that I did it alone. I certainly participated in the
decision because we wanted to get as close to the properties of the
dichlorotetrafluoroethane as we could. The boiling points were not far apart.
Therefore, the pressures and so forth would be about the same. We saw it was
going to be easy to make.
02:10:00BOHNING: The addition of HCl to TFE was already established in the literature.
PLUNKETT: I think the addition of HCl to TFE had already been done. There
certainly had been things added across the TFE double bond. I don't remember any
patent related to the other one. So it must have been done. The extraction of
the chlorine had been demonstrated by Henne a year or two before, and it just
02:11:00BOHNING: The route to TFE was also in the literature.
BOHNING: But it was not done in the scale that you were working with.
PLUNKETT: I have made the statement a number of times, but I don't know that I
could quantify it completely. I said until that time it was available in a few
grams at a time. Sometimes less than that.
BOHNING: I'm still intrigued by the quantity that you made. How long did it take
you to make the hundred pounds?
PLUNKETT: Well, Jim, I don't know now. I think I said someplace that I was
02:12:00assigned this problem in 1938. The Teflon discovery came on April sixth so it
got done in that period of time. [laughter] What I had to decide was what kind
of apparatus to use. I used a fairly large volume. I don't know whether I did it
all at once or not but I ran the Freon 114 into the alcohol-zinc solution. I
presume it had some temperature involved. The gas evolved and was collected in a
cylinder. It was cooled sufficiently to get it to condense. Then I took that
cylinder of gas and distilled it in the laboratory. That's how I got the
material I stored in the little bottles.
BOHNING: How did you maintain this at a low temperature? You said you had to
02:13:00keep it in dry ice. That's a large quantity to keep at such a low temperature.
PLUNKETT: We did quite a bit of work with low temperature materials in the
refrigeration business. We had a laboratory that had a good size storage box
that was kept cool all the time with carbon dioxide. So I kept it in the storage locker.
BOHNING: We've already covered the events of April sixth pretty thoroughly. When
did you decide to try and reproduce the polymerization? You started to look at
properties pretty quickly after you found the powder. But there's one other
thing I would like to ask you before that -- the decision to cut the tank open.
02:14:00I found that that's not on the transcript of our previous conversation. We only
talked about taking the valve off.
PLUNKETT: For years, I've said that after we didn't get enough out by scraping
and dumping it out, we decided to cut the tank open. I have been asked if it was
that day and I've got to say I don't remember exactly but it was very close. We
wanted to find out what happened to the weight. So I did cut it open but there
02:15:00was nothing mentioned of that on the sixth or the eighth. I haven't re-examined
that. A notebook might reveal it but I don't know right now.
BOHNING: Did you ever go back and make the original potential refrigerant that
you had set out to make?
PLUNKETT: I had made quite a bit of it. I don't remember now how much I made
afterwards. I'm sure that I did make some more because at the time we were in
the process of exposing guinea pigs to constant conditions of this new compound
mixed with air. It was really to see what the effects would be. The guinea pigs
were sacrificed after some periods of exposure and judged on whether there had
been any detrimental effects.
02:16:00[END OF AUDIO FILE 2.1]
BOHNING: Did that compound ever become a real refrigerant?
PLUNKETT: Yes, it did. It never reached commercialization. The impetus, as you
recall, is that the Frigidaire Corporation had proprietary rights to the other
02:18:00molecule. Such people as General Electric wanted to use it but Frigidaire
wouldn't let them use it. So they came to us to get a substitute. Frigidaire was
claiming some special properties and advantages for the 114. As time went on,
they apparently didn't maintain that advantage position and it got de-emphasized
so that the others didn't have the desire to compete. Of course, Freon 12, or
refrigerant 12 [CCl2F2], became the one of choice for the household refrigerator
almost exclusively and it still is today.
BOHNING: Were your activities after April sixth divided? Were you looking at
some of the properties of the polymer and also at the refrigerant?
02:19:00PLUNKETT: I'm sure they were. I recall that it was within a few months that I
got a completely new assignment. In that period of time, whatever I did was
joint. I don't know exactly when I got this other assignment. I think it might
have been as late as August. But in January of the next year I was transferred
to the manufacturing organization in the tetraethyl lead business.
BOHNING: You did some work on trying to repeat the polymerization.
02:20:00PLUNKETT: Yes. I ran a number of experiments in which I sealed TFE gas into
pressure tubes and stored it under various conditions with or without a specific
catalyst and with a specific catalyst in a solvent. I found that under those
broad conditions, I could get polymerization. I never did have a chance to do
enough of it to get any good at specifying the conditions. That was developed by
the people at the Experimental Station.
BOHNING: Did you have any specific reaction when you were transferred out of
that one position to the TEL plant?
PLUNKETT: No. My feeling has always been, Jim, that I was there and I accepted
02:21:00Du Pont as the place to work and if Du Pont thinks it's good for me, then it
must be good for me and so I'll do it. I never seriously questioned not doing
what they asked me to do.
BOHNING: At that point there was no realization of what this material really was
in terms of its commercial potential.
PLUNKETT: Yes. There was no realization of what Teflon might amount to.
BOHNING: As the development of Teflon continued later on, were you contacted at all?
PLUNKETT: I had contacts not in the technical sense but in the legal sense
because patents were being applied for and the original patent was issued in
02:22:001941. But then it was also patented in quite a few countries. Every time they
put one in a different country I had to sign a piece of paper.
BOHNING: In terms of the patent process, once you made your observations on
April sixth, this patent was applied on July first.
PLUNKETT: July 1, 1939.
BOHNING: So it was a year later. Would you as the person in the laboratory
initiate the patent process?
PLUNKETT: Yes. Any researcher could propose a patent on anything that he had
02:23:00done. The researcher had to make the original search as to whether it was
patentable or not. He had to make a scientific judgment as to whether it could
be patented and make a proposal for it to be patented.
BOHNING: You did that then?
PLUNKETT: As far as I know.
BOHNING: Is that lag of about a year normal for patent applications to take place?
PLUNKETT: They can vary all over the map. It takes a long time to get the
chemists and the lawyer to agree on what they're going to say. [laughter] It's
just like all other legal aspects. You get something to the lawyer and it may be
02:24:00a month or two months later before something comes back. That's not unusual. I
kept in touch in a way by knowing what was going on and knowing people who were
doing the work. I was also aware, in a minor way, of the Manhattan District work
that was going on at the site. Have you ever met Blaine McKusick?
PLUNKETT: Blaine McKusick was a research director at the Du Pont Experimental
Station when I was with Du Pont. He was the first one that made a contact with
me last year to give the talk that I gave yesterday at the AAAS meeting. He's
taken over leadership of the AAAS chemistry division from Rustum Roy, who I
02:25:00believe is now the chairman. I saw him yesterday afternoon and he asked me, "Did
the Manhattan people ever get you into the process?" I said, "If they did, I
didn't know it."
In the meantime, I was pretty well ensconced in the manufacturing of tetraethyl
lead and it was a pretty important field. When I expressed an interest at one
point in time of possibly doing more by offering my services to the country,
somebody said, "Well, if you do, you'll be right back here in a private's
uniform." [laughter] So that discouraged me from doing that.
02:26:00BOHNING: You did some of those early experiments to cause the polymerization. Do
you know when the first large scale polymerization started to take place? Was
that the work of Joyce and Hanford?
PLUNKETT: It grew out of what Joyce and Hanford did but they were doing
laboratory size things -- bench-scale stuff. The people at Jackson Laboratory,
Benning and McHarness and the group that I had been associated with, they
developed a larger scale process for making TFE and developed the pyrolysis of
02:27:00Freon 22. Then the group at Arlington did the
polymerization scale-up work. They were in the Plastics Department of DuPont.
The decision was made that they were going to let the Plastics Department
develop the material. This came in the early 1940s. The first large scale pilot
plant didn't get built until after the war. There were pilot plants of different
sizes. I don't know what to call large scale. But if you want to talk pound
quantities at a time, a few pounds or something like that, I'm sure that took
place in 1941, 1942 or somewhere in there.
02:28:00BOHNING: What was the catalyst of choice in the polymerization eventually?
PLUNKETT: I believe that the first commercial catalyst was persulfate. Aqueous polymerization.
BOHNING: I think I've asked the questions that I needed to tie up the loose ends
with. Is there anything else that you would like to add at this point?
02:29:00PLUNKETT: I can't think of anything right now. I've been happy to participate
with you in going over these things. You've tried to jar my memory and sometimes
it won't jar very well.
BOHNING: I appreciate all of the time that you spent with us and your
willingness to take more time this morning. Thank you very much.
[END OF AUDIO FILE 2.2]