PAUL J. FLORY Stanford University Stanfwd, Califmia
Interview with Paul J. Flory edited by
Inhmkmd by
ROBERT C. BRASTED
David W. Ridgway
University of Minnesota Minneapolis. Minnesota
University of California Berkeley, 94720
PETER FARAGO Burlington House London. England
h.F l w . since vou are one of the r n recent Nobel Award winners in chef&ry, our readers have an understandable interest h wur back&, W t i n f l w m d the develoansnt of your career in the field of polymers, andalso son&thing about you personally. Perhaps you might start at the beginning. Flory: I was born on 19 June, 1910, in Sterling. Illinois of HuauenotGerman parentage, mine being ihe & h generation native fo America. My faliw was Ezra F W , a c - w m my mother, nee Martha ~rumbaugh,hadbeen a schoolteacher. Both were descended from generations of fanners in the New World. They were the first of their families of record to have anendsd coilege. My interest in science, and in chemistry inpartIcular, was kindled by a remarkable teachar, Cari W. Holl, Pmfessorof Chemisirv at Manchester Collem. - . a liberal arts collece In Indiana. &re /graduatedin 1931. WMI his eIXX)UBge&nt lentered the Graduate Schoai of The Ohio State Universiiy where my interests turned to Physical Chemistry. Research for my dissertation was in ihe field of photochemistry and Spectroscopy. It was carried out under the guidance of ihe late Professor HerrickL. Johnston whose boundless zeal for scientific research made a lasting impression on his students. Upon completion of my PhO In 1934. Iloined ihe Central Research Department of the DuPont Company. Then,ii was my good fonune to be assigned to the small group headed by Dr Wallace H. Carothen- inventa of WkmandNeopene. a scientist of exiraordinary breadih and originality. was thrihe assmiation with him lhat I fimt became interested in exploration of the fundamentals of polymerization and p o l y m i c substances. His conviction lhat polymers are valid objects of scientific inquiryproved cofnagiws. The time was propitious, for the hypothesis that polymers are in fact covalently linked macromolecules hadbeen established by the works of Staudinger and of Carothers only a few years earlier. A year after the untimely death of Carothers In 1937, 1 joined the Basic Science Research Laboratory of ihe Universiiyof Cincinnati fora periodof twoyears. With the ouibreak of World War Ii and the urgency of research anddevelopment on synthetic rubber, the supply of which was imperiled. I rehwned to industry, first at the Esso (now ExxonJ Laboratories of the Standard Oil Development Company (1940-43) and later at the Research Laboratory of the Goodyear Tire and Rubber Company (1943-48). Provision of opportuniiies for continuationof basic research by these two indusirial laboratories to the limit that the severe pressures of the times wouldaliow, and their liberalpolicies on Ri%lwav:
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publication, permined continuation of the beginnings of a scientific career which might otherwise have been stifled by the exigencies of those difficult years. In 1948 i went to the Chemistry Department at Cwnell Universityand then, afiera brlefpedcdat Hx,Meikm ImtiMe, I came to Stanford in 196 1. Ridgway: You have enjoyed the opprtuniiy of working both In unlversities and in private indushy. What are ihe relatlve advantages and disadvantages of each? F b y : While the situation will surely vary from instiMion to instiiutkm and from company to company, there are ran,constrainis on the chemist working inprivate industry--also, it s e e m to me that there is a greater tendency to become isolated h the industrial lab&atory. The professor at a universiiy certainly has greater opportunities to indulge his flights of fancy and may cultivate a broader range of interests. On the othw hand, the industrial scientist can have ihe satisfaction of concrete achievements from his efforts. Ridgway: In your speech at the time you received the Nobel Award you said, "Inquiry into the spatial configuration of these longchain nwlecuies, fascinating in M f , derives wmpelling motivation from ifs close relevancy to thePoperlies imparted by such moiecules to the materials comprising them." Was there a point that you can remember when this compelling motivation came into focus? F b y : /I!ms a gradualprmess, born of e x p l e n c e endassoclatiom. The relevancy is self evident. lt surely was in the back of Carothers' mind. When he was browhi to DuPom to do basic research, ha carefully considered whet area of science he could devote himself to, which would, at once, have merlt as scientific endeavor, for which he hadgreat talent, andat the same time, offerpromise of benefit to his employer. He decided that the opining field of polymers was such an am-where science was ~ g e n i l yin need of motivathm and where practical applications were conceivably very great. We are now in the "polymer age" where polymeric materials are replacing both metals and non-metals. We are actually at the point where polymers are becoming more prevaleni as materials than metab. 1 am told that ihe volume usedalreadl.exceeds that of metals. Sfrmgih, elasticity, and durabilitv are the orooerties that commend them. . . Ridgway: Wimn World War 11 came along, was lt the extreme urgency of research and dewloomem in the fkldof svnthetk rubbers that demanded your affention? Flow: Yes. ~idgway: DMywr c m t i v e Mees concerning synthetic rubbers derive from your earlierstudies of ~olvmersand natural rubber? Flory: Yes, but they were by no means earth-shaking. My concerns mmr with physical and t'mofetlcal shdies in this field. In the Volume 54, Number 6. June 1977 / 341
30's there had been some p o d scientific work carried out on natural rubber. A swwisino arrav of information and knowledge about natural rubber, iocludlng its physical properties, had been acquired. The birth of the theory of rubber elasticity dates from about 1934-35. At the time of World War ii we hadat least a working idea, a conceptuaily valid, albeit imperfect, theory of the molecular basis of elasticity of rubber. Scientific understanding was at hand to guide the work that had to be carried out in great haste in order to create a synthetic rubber industw. And now, forty years later, we are still working at, and bn, the theory df rubber elasticity! R!dgway: Of your many co~'bvtionsmade to chemistry, which ones do YOU think have had the greatest imoacton the chemical community? Flory: Robably my book pubiished in 1953, "Principles of Poiymer Chemistry" a m u g h that's dodging the question a bit. That book was an effort to present principles and fundamentals of ihe fieidas of that date, cowing ihe wak of many people, including some of my own. We aN hadandhave a common obiective-to advance knowiedae in ihe fieid of w . lm . ers and macromolecules. Ridwav: - . You have always been. it seems to me. exiremehmodest: this is exemplified particularly in your & k n o w i ~ n tof what so mawneonie .. . d i d h the fiekt You always acknowiedge the team efforts. Flory: I've been accused to the contrary sometimes, but n's nice to hear you say it. Rtdgway: You have emphasized ihat you wen, e member of a teem of many people working to achieve some particular objective. F i w : Yes, knowiedgs in the flsM. R!dgway: Next l e t m a s k whatyarwnsideryougwatest~bution to. w what has chanoed the mode of iivlno or the activities of, the broad community the most? l a m suggesting contributions outside the field of chemistry. The replacement of many metals b y p o l m , for instance, has certainly hadan effect. You did make a contribution to that. Flory: Yes, indirectly, but quite indirectly. I think one couM correctly state that the cambiiiiv of a civilization. w esmcialiv ihe technical rciantific sector of a civilizatioi, is determined by ihe levelof its kmw)edss. mis doubtless is ihe limrtino factw h other areas of human endeavor as well. This is why we send c h i h n to schoolandon to wilege- to raise that level. So I think that if you pose a question-with respect to appiications, i would answer by suggesting that fundamental studies in the polymer field have raised the level of the understanding of it by the community ofscienlists, pure and applied, so that they can tackle problems intelligently and make greater advances. ThaI's not the reason that I find the advances in mivmer science most satisfvino, necessaritv. it isnl, i think, &t motivates most of us &&I in this fiek. Macromolecules are aliabout us and we ought therefore to try to understand them. Substances so intimate to us, and in us for that matter, should surely engage the interests of the scientist. Should he not turn to the scientific quest of these of aflsubstances that are so vitally important, both in living organisms, and in the world of man's creations and mifa&? Absbaci curiositymay be the main motivation. But it is more than abstract curiositv in this case-ii's concrete curiosityabout the materials that abound on every hand. Ridgway: That sounds iike an exiremely important kind of mtivation. As one chemist i was talking to aptlysaid, "Ws fun to know': When mere is somethino to which vw don't have an answer. s if you don? necessarily ask the &stlon, exactly what i w i n o to be mod for? Flory: ce;fainiy not! 6 n the other hand, I don9 want to discount the i-m of those who sirive to appw scieniifffi knowledge to create materials or to correct environmental sltustions or to amlv science h other ways. I think such motivations are exh&iy important, andone can derive a great deaiof satisfaction from feeiing that he has madesofns contribution,
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342 i Journal of Chemical Education
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even vicariously, to he$ those who are so committed. Ridgway: What was the state of the art h your field when you first became interested h macromolecules? Flory: It was a time when, at scientific gatherings, one's contemporaries midget up and raise ihe question openly, "Are ihese redly moi~coles?"Are ihey i ~ l covalent y molecules of such great size? The Issue had been largely resolved by Staudinger's work and advocacy, mainly in the 1920's. Staudinger's efforts, his experiments, his repeated long articles asserted that polymers are molecules and not aggrepeted colloids, as had previously been thought for forty w fifty years. Carothers commenced his work about that timeabout 1928 when he joined the DuPont Company. He considered that the issue of molecuiarity of potymers c w M be laid to rest by straightforward methods of organic synthesis. That is what he set out to do-not to develop Nylon, not to make Neoprene-but just to understand and to establish whether Or not these were molecules. Hisappmach was ihe epitome of clarity of concept and of simplicity. He set out to synthesize polymers of high molecular weight byprocedures free of ambiguity. He would then examine their prop erties. M they had the properlies of substances iike rubber and other materials, whose molecular nature was in contention, his evidence would be compelling. He convinced himself and his contemporariesquickly that they ware really macromolecules. He then became interested h studying them further and in synthesizing them in evergreater variety. AHhough that was the state of the art, there were still disbelievers. Methods for determining molecular weights w e not WeIiesfabiiM. There werea few but ihe pmblems of exirapolating to infinite ditution remained to be solved. There were osmometers but few people knew how to use them properly. Light scaiiering mNwds had to waitanother ten years for Debye to reveal iheirpotemiai. Omerphyscai methods mm, primitive. Unlike most chemicalsubstances where there is a one-to-one correspondence between the substance and a unique molecule of which it is composed, polymers c o r n prise a whie distribution of molecular species. The pmblem of molecular distribution,particularly the statistics of distribution, hadto be facedbefore one couldmake rational molecular interpretations. Ridgway: Do you feel that the subject of the macromolecular state represents uniquely complex systems? Fiory: On the contrary, the subject isn't complicated, and I would present arguments that macromolecules, as subjects of investigation, are no m e complicated than anything else. # depends, of course, on your point of view and approach. if one sets out to define the moiecuie uniquely and then determine all of its normal modes and all of its properties in detail, then of c o w polymers are hopelesslycompiex.Basr in mind, however, that whereas there are attainable goals for one small molecule, treatment of the assembly of such molecules comprisinga liquid in the same detail is likewise unthinkable. A iiquid consisting of polymeric molecules is not intrinsically a more difficuii object of inquiry than liquid hexane for example. In some respects, the polymer may be less rmndite. Truly, compiexityand difficuw are subjedive jujgments. Ridgway: Did funding fw equipment svpplles,andso rath e w p s e m any problems to you? Did you or have you fen constrained by unique barriers? Fiory: icwidnot always get ail of the funds i wanted, but I must admd to having wuaily hadas much as my needs required. If one can't purchase an expensive piece of equipment, then he may turn to pencil and paper. Sometimes that turns out to be more productive. Pmgress is aiways confronted by barriers. I'm fnrstrated m s t of the time-scientifically. Always lhers are problems I woutd like to solve that i can'tget roper hold of. One needs to have mon, than one problem to think about. Otherwise he may bruise his head on the proverbial
stone wall to the point of suffering a concussion. There is a difficun m a w of balance here which e v e m has to work oui for h l m i f . To hop hornone problem to another can lead to superficiality. One needs to dig in, in depth. Just brush aside all the debris on the desk and concentrate on one thing at a time-as long as ha doesn't reach the wall of uner fmtratia~.One has to know when he is at ihat poiniand ihan turn to another problem. Later, he may reiurn and try agah. Ridgway: What do you see in the future in tha area of macromolecules? Flory: lam concemedthat the fieldis not receiving enough anention in the domain of pure science, of basic chemistry and physics. Ii's being relegated to ihe appliedandengineering branches. ldon'tmean to suggest ihat this is undesirable in iiseif. Thwe is much merii in the giuwing interest in the field in materials science departments, in chemical engineering deparimenb, and, in someplaces, in appliedphysics. At the same time, the fieidshouldattract to it students and faculiy with more abstract andbasic science orientations. Neglect in this respect, I think, wili not only be to the deiriment of polymer chemistry, but to the detriment of chemistry as a whole. The field of chemistry cannot afford to abandon a sector of such widespread relevancy. Ridgway: Are we evergoing to run out of materials forpolymers and plastics in the way we are in danger of exhausting some of our other natural resources? Fiory: Certainly we face a raw material problem. The major source at present b petroleum. We could shin to coal. Then in a century or so from now, as our coal resources dwindle, we might turn to agricultural sources. This approach, however, would compete with food. At least there is a diversity of potential sources of raw materiab. i would make the Observation that the development of an abundance of Cheap, iow-grade polymeric materiab for everyihing under the sun has spawned a throw-away economy that is wasteful to a degree that we cannot long tolerate. h ihe future we should turn to development and production of more durable, bener materials, Replacement turn-over would be lessened and raw material requirements couMbe rmch mdw& Examples are ttm aramide synthetic fibers that are now coming into uK, for tire cords and certain other nonwearing apparel applications. Their strength is five times that of steel, if figured on a weight bask. This was unforeseen five or ten years ago. We should not assume necessarily ihat this is the limit. Improved polymeric materials will extend their use, and their replacemmi of other materials will continue. But we must usepolympmperlyandefficiently. This willrequiread~saf deal of discipline both on the part of industry and of the consuming public. We may have to change our anitudes toward polymeric materials as cheap products that can be used once and thrown away. We must insist on quality and durability in order that smaller quantities will serve a given function better and longer. Ridgway: What new t w l s are now available that might provide the expeciation of large or quantum jumps in our knowledge? Flory: h e r e is a continuing developmeniof inshnnenfs, aliImI!gtI not at a rapid rate. Because most of the effort has been in indusirial laboratories, the emphasis has been on mechanical measurements. The development of sophisticated instruments for fundamental studies has received less attention. Ridgway: Many of our readers are persons concerned with graduate school and, eventually, a thesis adviser. What do you look for in a young person who wants to come and work for YOU? Flory: Some evidsnce ihat he Is genuinely interested In the flald or has a mtivation toacquirean interest in the field, but Ihave no g a w ihat wouldapply to every candate graduate studsnt and post doctoral fellow. I haven't found such an instrument. Ridgway: Regarding those t r a k whichyou consider Important, do y w
ihink ihat over the years there are indications ihat the training they have gonen prior to arrival has been getting beiisr or worse? Flory: Unfortunately, most students graduating from college have virtualiy no exposure to macromolecules or to the basic I only principles of macromolecular science. They know / superficially in terms of its applications in industfy and in biology. I'm retired now, but even before retirement I wasn't allowed to teach undergaduate courses at Stanford. lmight have indoctrinated students with false and dangerous ideas. Ridawav: - , Has ihere beenan increased Interest h wlvmer chamistrv and macromolecules at the undergraduate level? F b v : If so. it has not been e v M . Mast of ttm interest b fmm .m ~ . l e outside ihe university. Some instructors pay lip service by iniectino materiaion macromolecules in one or two lectwes . at the end of a course, or by adding a chapter at the end of the text. This is worse ihan nothing. lishouid be interwoven into the syllabus of the course orinto the textbook. Ridgway: Did you enjoy teaching? Flory: Yes. Ridway: Presumably, i f y w are teaching, fhose i h a t w are teaching know less abiuf the subject ihan you do. is it possible for students at any level to contribute to research ihatyou are doing, which is actually far in advance of theC thinking? Flory: Everyone who has taught, and I enjoy teaching, has sought to recast his subject maner from a fresh viewpoint, and this quest ofien brings forth points of view that have been overlwkedor forgotten..This is helpful to the teacheras weNas to ihe student. The reaction of studenb is ofien stimulating, t w . and has suggestive Dower that can carry over into re: search. I don i iirnk one should teach lor ;he purpose of benetiting from the reactions of his srudents, but that ihis can be a sowce 01 ideas andst;mulationis a fact. But bear in mind that time devoted to research does take away time which might be devoted to teachingand teaching takes rime that mtght be devoted to research. My answer is still that there Is a positive correlation between the two activities. This fa. m b i e m i a t i o n d o e s cot take intoaccornt the i o s of time of one for the othar, but ihis is like everything eke in life. We have to make choices and balance objectives, one with the other. The indusirial researcher tends to become isolated from the core subjeci matter. Ridgway: Can you suggest changes in Me structure of Chemistry Departments, or even the universiiy, which would provide for greater Droductivity in facilities while stMi maintaining, or &en improving, tNK) quality of education? Your wide s,mchrm of industrial and academic ekwrkllce would make your suggestions unique. F W : I think there are departments over the counir~that, from my obsewations, have tended to become fragmented. This is a widely recognized malady. There is nothing novel about this answer. According to my observations. Chemistry Departments have become fragmented into as many different branches as there are pr&ssors. This tends to isolate people-faculty and students as well. Students are more adept at overcoming ihis ihan facuKy. y . readily tramqess the artificial boundaries of the "sub-sub"discip1ines and speciaities. I think fragmentation is a growing problem. It's w-ly r e c q i l e d , however, and therefore, willbe addressed and orobablv be remedied in due course. Unfortunatelv. anyihing admlnisirators are likely to do probably would be in the wrong direction. I think it is a problem forthe individual faculty to solve. Responsible faculty are well aware of the oroblem. On the oositive side, let me sav that in my . opinion . our universities, aided by government grants, have made enormous coniributions to science in the m t - w a r Years. This willsurely be lwkedupon as anage in which science. including chemistry, has flourished. Ridgway: Are there special responsibilities ihat tha scientist should bear towards society other than those m l l y encountered in the life of a community? What is the scientist's special
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role, pariicularly with regard to helping with decision making concerning the various technologicaldevelopments which affect all of us? Flory: Hs shouldmake his e x w i s e available and take positive steps to bring it to bear on issues. However. I think he has a responsibility to confine h b rerommendations and unerallces to ihme areas in which he is knowledgeable. To make public statements wh& ones area of expertise canbe mislsadng to others. Ws a form of dishonesty. Yet, as a cliimn one has a responsibflityto make his v i e w known. He cannot excuse himself from making value judgments altogether, even outs& of his professional fietd. He must play the part of a gwd cifizen. Om w t d like to be able to say. "These are the facts within the purview of my special knowledge': then draw a line and say, "Mw, as a citizen, my valuejudgmsnt is so and so." The clear distinction behveen two such assertions is an ideal seldom achieved in practice. Ridgway: Do you have any suggestions for administrativeor political bodies concerning the environment and its protection? Flory: Scientish are taking an increased interest in environmental problems, even beyond the limits of the s u m they get fw their researches in this area. A great deal, I'm sure, needs to be done. R's exceedingly important. The trade-offsaren'i always appreciated. There are those who say ihat polymers are using up raw materials too rapldly hbwever, a closer analysis may show that the increasing use has bean more ihan justified by the relief to other sources of raw materials including agricumKa1 lands much needed fcffood prcductbn. For instance, the resourceful organic chemists can synthesize the raw materials from virtually any source of carbon. /f you recall the times of World War 11, there were efforis backed by a lobby to make synthetic rubber from grain aC cohol, an agriculturalsource. They ignored, or chose not to "advertise", the fact that grain alcohol coutd be produced more economicaliy fmmpeiroleum sources. To turn in that direction in the future would, of course, be possible, albeit at the expense of decreasing the available food. RMgway: Now let's toucha bit on thapersomlandnon-technicalaspects of ywr career. What extracurricular activities do you engage in? Flory: I'm too busy to do very much. 1like to visit art museums. We've collected a liitle. Some reading-to the extent that time permits. I like to bicycle, swim. and hike. RMgway: Have your interests and accomplishments hadan effect on the educational and professional accomplishmenh of your children? You have a preny nice family. Flory: Ithhk so. Because 1followedmy father's principle that ChiMren shouldmake their own decisions on careers, lresolvednot to interfere with theirs. Ironically, my olderdaughter majored in mathematics, the second one in physics, and my son majored in chemisiry, then switched to biology and biophysics. I had nothing to do with their decisions. Rldgway: Isn't iipossible that as a scientist andas a parent, that you had more to do with their decisions than you may thinkperhaps Sheer admiration for your own accomplishments? Flory: I Idon't know. 1don't mink admire is the rigM word. 1lihink a young person could admire his parents and yet devote himself to an entirely different field. Admiration need not lead him necessarily into the same direction. It might even repel him
344 / Journal of Chemical Eduoltion
and I think ihat ~ o m e t l m ehappens. ~ I'm sure there were influences that moved them into academic circles. it was a l w q taken for granted ihat they were going to college. They were encouraged to love books, and my wife, their mother, was always interested in exposing them to cultural opportunities appropriate to their ages. This has carried through to their interest in art, music, andgood reading. Rtdgway: Thb is one of the kinds of things thata lot of youngsters in underpiivilegedhomes just simply don't get. Flory: T m . Rldgway: You always had books around for your youngsters. Flory: Before hvo years of age, they were all read to-whether they really followed it or not, we are not sure. Rldgway: I bet they were aN reading before they went to schwl. Flory: Yes. Ridgway: Do you see any areas of our science or relatedareas that are being neglected? F W Aciualty, 1thmink my own fietdis neglected I think there am many areas of sclence that are neglected. If a young man is aleri to those tantalizing aspects of nature, on?encloseat handeven hitting him in the face, so to speak--he might be aware that here before him is a neglectedscientific field. Then he should engage himself in it. RiaJway Let's assume ihat you are againa 21-year old, emerging with a BS a BA degree. Are there durllenges or f~Iffulareasnow ihat would suggest some other career than the one you pursued? Flory: If I were to responddirectly to that questlon, my opinion would be of linle worth as a recommendation. So much depends upon the individual. He must consider his interests andabilities andhow they relate to what he would like to do. Idon't thinkanyone else cananswer for him. There is anotherpoint ihat must be taken into consideration. At age 21, for some ii's all laid out-he knows exactly what he wants to do. Another may have to stumble about in the wilderness for 10 years before he finds his bent. I don't think you can sayabstractly that this a that $ a fmitfularea. It becomes fruitful when s o m has an idea, a concept. He planh a seed. M cultivates it. AN science is a human creation that seeks to understand and describe observable phenomnra in fhe wwM and universe about us. A fieldof science isn't a preexistent thing. It is what man makes of it. So I wouldn't look for the latencies to be developed. I think it depends on what individuals discover to develop in response to stimuli from experience. There are many branches and sub branches of chemistry where very significant coniributbns will be made. Thase that do flourish willdo so because of the people who become interested in them. Rldgway: I'm reminded of the reason you took your first job. The objective there, it seems, was that you had to make a living. Flory: You're so right, it was! R was an urgent objective. Ridgway: Do you think that now, because things are relatively more prosperous, it is more difficuli to come to decisions about what one wants to do? The demand to make a decision is certainly less urwnt. Flory: Yes. If may be more difficuli for young persons today because the pressures for an immediate decision are not so great. But to leave the mamK h r e is to fwget the s e w @ o f ihme economic pressures forty years ago.
