The Multiplicity of Industrial R&D That Produced High-Strength Aramid Fibers

Home , Du Pont family, Wallace Carothers

Technology In Society 21 (1999) 37–61

A battle of giants: the multiplicity of industrial R&D that produced high-strength aramid ﬁbers Karel F. Mulder* Faculty of Technology and Society, Delft University of Technology, De Vries van Heystplantsoen 2, 2628 RZ Delft, The Netherlands

Abstract

There have been several long and expensive legal disputes on important results of industrial R&D. These disputes are often very destructive for all parties involved; the lawsuits are very expensive, market development for new products suffers from the uncertainty of uninterrupted supply, and the parties involved are often forced to publish technological and trade secrets, thereby helping third parties. This article analyses the R&D, starting shortly after World War II, that led to high strength/high tenacity aramid fibers in the 1970s and 80s. The development of these fibers led to an enormous patent litigation case between the chemical giants Du Pont (US) and AKZO (Europe). This paper will show that industrial research and development, especially pioneering research, is not so straightforward as is supposed in international patent law: often research findings cannot be covered easily and effectively with patents; “inventions” are often the result of research findings in various laboratories. Competitors can often improve on the product or the process, and thereby claim patent licenses. Therefore, patent rights are in practice more or less a matter of negotiation while the legal situation is often rather unclear. This paper will briefly describe how, amongst others, Du Pont, Monsanto, AKZO, and the Soviet VNIIV and VNIISV institutes contributed to the creation of various high performance aramid fibers. It will also describe how the patent litigation struggle between AKZO and Du Pont started, and will finally evaluate this battle of giants, which cost the parties about US$200 million only for lawyers, and probably a multiple of that amount to cover other expenses.  1999 Elsevier Science Ltd. All rights reserved.

Keywords: Patent litigation; Industrial research; High performance ﬁbers

* Tel.: 31-15-278-1043; fax: 31-15-278-3177; e-mail: [email protected]

1. Introduction

There have been several long and expensive legal disputes over important results that have evolved out of industrial R&D. Some well-known examples are the patent litigation cases between Polaroid and Kodak over the instant camera; the case between Alpex and Nintendo regarding video game graphics [1], and between Du Pont, Montecatini, Phillips, Hercules and Standard Oil of Indiana over polypropylene [2,3]. Disputes over appropriation of industrial technologies are often destructive for all the involved parties. Lawsuits are expensive, market development for new products suffers from uncertainties of supply, and the parties are often forced to publish technological and trade secrets—often beneficial only to competitive third parties. These conflicts cannot be satisfactorily explained in the rational economic terms whereby large industries generally formulate their strategy. This paper aims to elucidate the process by which these conflicts arise. It begins by analyzing the post-World War II R&D that led to the development in the 1970s and 1980s of high strength/high tenacity aramid1 fibers like Kevlar and Twaron2 in the 1970s and 1980s. The development of these fibers brought on patent litigation between the chemical giants Du Pont (US) and AKZO-Nobel (The Netherlands/Germany). From 1979 on, these two companies filed various suits against each other, finally reaching agreement in 1988. However, the animosity between these adversaries remained, and in the 1990s they filed suit again, this time alleging unfair trading practices. In some respects this paper is a simplification of reality: it deals only with Du Pont, Monsanto, AKZO, and two Soviet research institutes. In fact, several other corporations have contributed to this field of research, such as Celanese, ICI, Hoechst, Rhoˆne Poulenc, Teijin, and Asahi. The paper illustrates several key points: ț that industrial R&D, especially basic research, is not as straightforward as is supposed in international patent law; ț that research findings often cannot be covered easily and effectively with patents; ț that “inventions” frequently result from combinations of research findings, all of which are known. Moreover, although it might be hard to believe, there are numerous examples of similar research results that have been independently achieved at various disparate

1 Aramid fibers: aromatic polyamide fibers. Fibers are measured in denier, a traditional textile standard. If a fiber is 1 denier, its weight is 1 g for 9000 m of fiber. Fiber strength is measured in grams per denier (gpd). The strength in gpd means the maximum weight that a fiber can carry at break, divided by its denier number. The tenacity of a fiber is expressed by its modulus. The modulus is defined as the relative tension applied to a fiber (g/denier) divided by the relative increase in its length. Therefore, a 1-denier fiber with a length of 1 m, to which a force is applied of 1 g gravity, increasing this length by 10 cm, has a modulus of 10 g/denier. 2 Registered trademarks of Du Pont and AKZO-Nobel, respectively. K.F. Mulder/Technology In Society 21 (1999) 37–61 39 locations. Independent research frequently continues after the “invention” has been patented: competitors often improve on the product or the process, and then claim patent licenses. Therefore, in practice patent rights are more or less a matter of negotiation. This creates an opening for intimidation on the part of corporations that may try to scare off competitors simply by threatening litigation. Because the situation is so murky, corporate patent attorneys face a difficult job. They can be pressured to yield to the demands of researchers and managers who often assess legal situations in their own favor. However, serious trouble can arise even if they are able to make a proper judgment of patent positions regarding a specific technology.

2. Du Pont

In the 1920s and 1930s new research had created a scientiﬁc basis for polymer technology [4]. The US company Du Pont was notably at the forefront of polymer science. The company had positioned itself at the center of a network of polymer scientists. Its main polymer scientist, Wallace H. Carothers, not only contributed enormously to polymer science, but also invented nylon and neoprene rubber [5].When Carothers was hired, his teachers, Roger Adams and Carl Marvel, also became Du Pont consultants. When war began, Du Pont arranged for the Jewish- Austrian refugee, Herman Mark, to become a consultant, and he was appointed a professor at Brooklyn Polytechnic [6]. Mark was also in regular contact with other corporations such as Dow Chemical, Shell, 3M and Monsanto Plastics [7]. However, he visited Du Pont about once a week, and the others about once a month [8]. Paul Flory was also in regular contact with Du Pont. He started his career at Du Pont’s nylon research labs in 1936.3 Nylon was a successful, shining example of industrial R&D. At Du Pont, the search focused on new nylons [10] and the research that ultimately resulted in nylon

3 These scientists all have to be ranked as belonging to the top of American polymer science: Mark had made a career in Europe. He had worked at the Kaiser Wilhelm Institut in Berlin, at IG Farben in Ludwigshafen, and had been a professor in Vienna. He played a profound role in the scientific controversies on Staudinger’s macromolecular theory. After World War II, he founded the first scientific journal on polymer science. In the 1960s, he was the editor of the Encyclopedia of Polymer Science. Flory left Du Pont in 1938. Afterward, he worked for Standard Oil and Goodyear. He also worked at the Mellon Institute, and was a professor at Cincinnati, Cornell, and Stanford Universities. His book on polymers [77] became the basic textbook for students of polymer science. He received the Nobel Prize in 1974. Flory died in 1985 [9]. Marvel and Adams were both professors at the University of Illinois. Carothers was a graduate student under them. In 1928, they began alternate monthly visits to Du Pont. Forty-six of Marvel’s Ph.D. students joined Du Pont. One, Salzberg, became head of Du Pont’s Chemical Department in the 1950s. Marvel was also a consultant for the Air Force program on heat resistant fibers in the 1950s. After his retirement in 1960, he worked at the University of Arizona. It is estimated that during his career he stayed at the Hotel Du Pont in Wilmington for 1320 nights (three and half years) while consulting with the corporation. Marvel died in 1987. 40 K.F. Mulder/Technology In Society 21 (1999) 37–61 typified the trust that Du Pont’s leadership placed in its chemists: “Better things for better living$through chemistry.”4

2.1. Low temperature polycondensation5 research

Du Pont’s laboratory for new fiber R&D was the Textile Fibers Division’s Pion- eering Research Laboratory (hereinafter referred to as “Pioneering”). In October 1948, Pioneering manager Hale Charch, set out 11 goals for the future development of new fibers. Charch believed that Du Pont was at the beginning of a “synthetic textile revolution”. He stated: “As our basic knowledge of fiber properties is enlarged, we are truly approaching the time we can deliver fibers to predetermined specifi- cations” [11]. He believed that synthetic fibers would have great potential, and that Du Pont would be in front owing to its enormous technical lead over its competitors [12]. Among the goals was the development of fibers that would remain stable at high temperatures, high-strength fibers, inexpensive fibers, wool-like fibers, and elas- tic fibers. In 1948, Emerson L. Wittbecker tried to make polyurethanes in a new way. He worked on a polymerization method that was studied by IG Farben and described in a report from the Allied Technical Industrial Intelligence Committee [13]. The key feature of the new method was making polymers at the interface of two immiscible solvents each of which contained a monomer [14]. In 1950, Wittbecker success- fully created polyurethanes of relatively high molecular weight.6 These polyurethanes were still not suitable for making fibers. But Wittbecker and his fellow scientists recognized that the method could probably be applied to other polycondensation reactions, in which case many new polymers could be produced because, contrary to conventional methods, no heat was involved. It was therefore possible to use thermally unstable intermediates. By the end of 1950, various Pioneering scientists began to use the method, which became known as “interfacial polycondensation”. The following procedure was used:

Two monomers were dissolved in two immiscible solvents (one of which was generally water and the other an organic solvent), after which the polymer formed at the interface of the solvents which were normally vigorously stirred [15].

With this procedure, many new polymers were made: “The number was so great, about 10 each day, that people became worried whether one could evaluate all of them” [16]. The scientists decided to divide the ﬁeld into areas that could be studied by small teams. In January 1951, Paul W. Morgan was invited to study the fundamentals of

4 The corporate slogan adopted by Du Pont in 1939. 5 Nylon is a speciﬁc type of polyamide, polyamide 6,6. Polyamides are made by polycondensation reactions. 6 The main problem Wittbecker had to overcome was the hydrolysis of one of the intermediates during the reaction. Hydrolysis terminated the reaction and the polymers that resulted had a low molecular weight. K.F. Mulder/Technology In Society 21 (1999) 37–61 41 the process [12]. Morgan was just the right kind of person for basic research in an industrial setting. He combined academic interest in the nature of polymer formation with the attitude that this research had to bring something tangible to the company [17]. Although the scientists were enthusiastic, no interesting new products initially came from the research. Still, conﬁdence was not lost. A spectacular trick, developed by Morgan in 1951, impressed many people:

Nylon intermediates were dissolved in two immiscible solvents. When they were poured into the same beaker, a film formed at the interface. As the film was pulled out, it collapsed to form a rope. New film formed continuously and lots of nylon rope could be drawn. If the rope was led over a pulley, it was drawn further by its own weight [18].

However, a disadvantage of the new method rapidly became apparent. In contrast to polymers made by conventional methods, the molecular weights of the polymers made by the new method were dispersed over a wide range. Attempts by the nylon laboratory to make nylon ﬁbers using the new method failed, as did the preparation of more complex polymers. Consequently, Morgan tried to make polymers in a somewhat different way. In 1953, he succeeded in carrying out polycondensations in a single-phase solvent system. This method was quite attractive because it created the ability to feed the solution in which polymers were made directly into spinning machines to form ﬁbers.7 Therefore, much effort was invested in the optimization of this solution polycondensation method [12].

2.2. Heat-resistant ﬁbers: MPD-I

A special class of polymers, known as aromatic polyamides, could not be made by conventional methods because the monomers of these polymers were thermally unstable. Thus, the low-temperature method seemed to hold great potential for making them. Pioneering scientists expected these polymers to be highly stable, just as half-aromatic polyesters were more stable than their non-aromatic equivalents. Improved stability would mean fibers with improved heat resistance and greater mechanical strength. Perhaps an aromatic polyamide fiber could also be used as a non-flatspotting nylon tire cord,8 an important R&D aim. In the early 1950s, Pioneering made numerous wholly aromatic polyamides. Most of them could not be processed into fibers because they were generally intractable and their molecular weights were often too low. Another Pioneering scientist, Wilfred Sweeney, tried to determine the best building blocks for an aromatic polyamide.

7 When the interfacial method was used, the polymer had to be separated from the solvents in which it was formed and redissolved before wet or dry spinning could be applied. 8 Flatspotting, which only occurred in the 1950s and 1960s, refers to the ﬂat spot which tires get when they cool down. These spots are a nuisance when driving off again. 42 K.F. Mulder/Technology In Society 21 (1999) 37–61

While Morgan and his co-workers had rejected all meta-configured building blocks9, and the para-configured polymers proved to be intractable [11], Sweeney succeeded in making a high molecular weight, wholly aromatic polyamide, known as MPD- I,10 by using a modified interfacial polycondensation process. He was able to spin a fiber and also realized high heat and flame resistance [12]. The process of polymerization and spinning were further improved by Morgan and Kwolek [19]. They discovered that molecular weights could be improved by the addition of salts. This discovery was unforeseen:

At the time the only available source of pure meta-phenylenediamine was the di- hydro-chloride. So we used the salt with four moles of triethylamine: two were to free the diamine from the unreactive salt and two to neutralize the byproduct, hydrogen chloride, of the polymerization. High polymer resulted. Later when pure, free diamine became available, we only obtained low polymers. The difference was traced to the extra byproduct, salt [20].

This modified interfacial polycondensation process was used to produce MPD-I fiber on a somewhat larger scale. In the summer of 1955, production of a good fiber became possible. This was the first fiber that could be heated above 300°C. Its strength was similar to nylon, but the tenacity of the fiber was about three times that of nylon. In addition, MPD-I could also be used to make a paper. This paper was a good insulator which could replace cellulose-insulating paper in electrical machinery. This use increased the attractiveness of the development of the MPD-I fiber. When the MPD-I fiber became producible on a larger scale, Wayne Sorenson was assigned to develop the most viable means of making the fiber. The main problem in a solution polycondensation process had been to keep the polymer in solution long enough to form high polymers while at the same time the hydrochloric acid that was formed had to be removed. Sorenson discovered that he could simplify the polymerization system by using amide solvents11 that could accept the hydrochloric acid. This procedure became known as “modified solution polycondensation”. The modified solution polycondensation method became the basic procedure for making aromatic polyamides [21]. In 1958, Du Pont began a development project for the MPD-I fiber [11]. The project and the fiber were given the name HT-1. In 1961, a decision was made to build a small plant in Richmond, Virginia, which came onstream at the end of 1962 [22]. The HT-1 fiber was given the trademark name Nomex. Various Nomex applications were developed, such as conveyer belts reinforcements, special tires, hoses, protective garments, and filter cloth.

9 “Para” means that these elements of molecules are straight. “Meta” means that the elements are bent. Meta elements were therefore rejected, as they could never create crystalline structures. 10 Meta-Phenylene-Diamine combined with Isophtaloyl-chloride. 11 For example, dimethylacetamide, N-methyl-pyrrolidone, tetramethylurea and hexamethylphosphortri- amide. K.F. Mulder/Technology In Society 21 (1999) 37–61 43

2.3. An information leak?

In the early 1950s, Pioneering scientists believed they were breaking new ground, and consultants were almost never used: “When we were working in a field which was rather unique, we were trying at least to keep it quiet until we were at a point that we could get patents and publish” [23]. The US Air Force Materials Laboratory was approached to discuss the properties of the MPD-I fiber [24]. Contrary to expectations, the Air Force was much more interested in this fiber as a heat-resistant material for drogue chutes for jets and spacecraft, and far less interested in its use as a non-flatspotting tire cord for aircraft tires. Du Pont consultant Marvel played an important role in setting up the Air Force R&D program on heat resistant fibers. The Air Force Materials Lab thoroughly evaluated the fibers [25]. Unfortunately, the Lab did not maintain confidentiality regarding Du Pont’s data. In August 1955, the Weatherhead Company approached Du Pont. The Air Force had told Weatherhead about Du Pont’s new fiber, and Weatherhead wanted to use it to make an aircraft hose assembly. A little later, General Electric also approached Du Pont to hear more about the fiber. Du Pont fiercely denied having a high-temperature fiber and supposed that the Air Force had only been confused by a market study that Du Pont had been carrying out on the potential market for such a fiber [24]. In November 1955, scientists visited US Rubber and agreed that this company would evaluate MPD-I tire cords under strict conditions of confidentiality. The relationship between Du Pont and US Rubber could be controlled by the fact that the Du Pont family held 17% of the outstanding stock of US Rubber, and had appointed a board member [26]. Pioneering asked Herman Mark to keep an eye on the efforts of competitors.12 In 1956, Mark presided at a IUPAC polymer conference in Japan. He had an audience with the Japanese emperor who was keenly interested in natural sciences. Because a first patent had been issued, and after long deliberations, Mark was allowed to show the nylon rope trick to him [6,8] (pp. 88–89). Meanwhile, Pioneering scientist Marvel remained an important consultant; Adams had died; and the relationship with Flory had been terminated because it was incom- patible with his position at the Mellon Institute. Around 1956, scientists from competing firms had uncovered clues about Pioneering’s work and urged Morgan to publish. Permission for publication, which any Du Pont department could oppose, was withheld until 1957. In that year, the interfacial polycondensation method was presented at the annual Gordon Conference, a rather informal meeting of polymer scientists. No papers were presented nor were there any transcripts. In 1958, several Pioneering scientists presented papers on the interfacial polymerization method at the annual American

12 Mark visited many laboratories. He later called himself, “a trading post of information on polymer science developments between the U.S., Europe, and Japan” [27]. “Mark constituted a one-man early warning system on new developments in polymers for a number of research laboratories for whom he consulted” [28]. 44 K.F. Mulder/Technology In Society 21 (1999) 37–61

Chemical Society Meeting in Chicago [17,29]. However, their papers only appeared in print in 1959 [15,18]. The single-phase method was kept secret until 1963 [30]. Just before he died in 1958, Hale Charch had approved publication of the research work. Georg Lanzl followed Hale Charch, and he had been involved in this decision. He later said that if he had known what was going to happen, he would never have allowed publication. People from other companies told several Du Pont managers that publication of those papers helped their scientists tremendously [31]. However, the Air Force was probably more responsible for leaking than the publications of the scientists. Anyway, rumors about Du Pont’s work were spreading among polymer scientists. In the 1950s, various other corporations began to use similar methods, paying little attention to Du Pont’s work. Examples include Celanese, which applied solution methods to make polyurethanes; Bayer [32,75], and General Electric, both of which made polycarbonates [33]. The Pioneering scientists rightfully feared that they were losing their priority claims.

3. Chemstrand

Chemstrand, a joint venture of Monsanto and Avisco, was one of the corporations that heard rumors about Du Pont’s “solution polycondensation” method. Monsanto, based in St Louis, Missouri, went into fibers in 1942. In 1949, it took Avisco as a partner in order to commercialize its new acrylic fiber, Acrilan. Initially, the joint venture was not particularly successful. However, it acquired the first license to produce nylon, which proved to be a gold mine for the venture. At Chemstrand headquarters in New York City, the company “ran its own show”. Chemstrand managers sometimes boasted, “We are no chemists”, and talked about Monsanto as “the guys out in the prairies” [34]. In January 1961, Chemstrand became a wholly owned subsidiary of Monsanto. However, the company retained its own culture. It resisted a transfer of the headquarters to St Louis by claiming that Chem- strand had to be where “the textiles action is”: New York City. Shortly before the Monsanto takeover, Chemstrand’s R&D facilities were transferred to new facilities at Durham, North Carolina.

3.1. Low-temperature polycondensation

In the 1950s, Chemstrand scientists were eager to become involved in the new and challenging research on heat-resistant fibers. They approached the Air Force and tried to establish better relations with Marvel and his research group. In 1958, patents revealed some features of the new low-temperature polycondensation methods developed by Du Pont. The Air Force Materials Laboratory did not want to be wholly dependent on Du Pont. Therefore, it gave Chemstrand a piece of Du Pont’s HT-1 fiber. As a result, Chemstrand scientists learned what Du Pont was working on, and soon they were able to duplicate the fiber. However, they expected that Du Pont K.F. Mulder/Technology In Society 21 (1999) 37–61 45 would have several patent applications pending. Therefore, several Chemstrand research groups explored various ideas that could possibly lead to a similar fiber but one that would probably not be covered by patents. The Air Force encouraged this exploration by granting some research contracts. Chemstrand scientists began working in several directions: (a) One research group made an analogue of HT-1.13 This work was finished suc- cessfully and the fiber had most of the properties of HT-1 [35]. (b) Another group managed to synthesize an all-para, wholly aromatic polyamide [36]. However, this polymer was too intractable to form a fiber. (c) The US Air Force supported a research project to develop a phenyl-triazole fiber. These polymers were first made by Marvel [37]. It was discovered that these polymers were not appropriate for fibers, and the project was terminated. In December 1964, a proposal was made to the Air Force to make a number of other heat-resistant polymers instead, but the Air Force was not interested in them.

3.2. Aromatic polyamides

The preparation of the all-para wholly aromatic polyamide was a great achievement. Du Pont’s scientists were shocked when they learned about it [12]. A laboratory technician, Herbert Morgan, achieved another important result. He elaborated on an almost unknown spinning method. This air gap spinning method14 worked well for aromatic polyamides and gave superior fiber properties [38]. Because (b) and (c) above had failed, only the project which used the analogue polymer of HT- 1 was left. Later on, it turned out that Du Pont patents covered the analogue as well. Then someone conceived the idea of using as one of the intermediates diamines that contained two or more aromatic rings connected by amide linkages. The advan- tage of this method was that part of the polymerization was already done when this diamine was made. Thus, there was lower heat and less hydrochloric acid as a byproduct to dispose of when the actual polymerization was performed. In this way one could also polymerize with terephtaloyl chloride which was cheaper than isophtaloyl chloride.15 Various polymers were made using this new approach [39]. A polymer called M3P16 was found which could be spun into a fiber with properties almost identical to those of Du Pont’s HT-1. The intermediates would be somewhat more expensive than those of HT-1, but fiber manufacture would be less complicated and ultimately cheaper. The project and the fiber were given the name X-101. In 1964,

13 This is a polymer with slightly different ordering of the building blocks. 14 This is also known as “dry-jet-wet spinning”: leaving an air gap of about 1 cm between the nozzle and the spin bath. 15 That is, one did not react single aromatic rings with two functional units (NH or CO) attached to them. Instead, one first made diamines which contained two or more aromatic rings that were connected by amide bonds. These diamines were polymerized with phtaloyl chlorides. 16 M3P: three meta linkages in the pre-formed diamine polymerized with one para terephtaloyl-di- chloride. The resulting polymer had the ABAABABB order. 46 K.F. Mulder/Technology In Society 21 (1999) 37–61 some of the properties of this polymer and other related polymers were published [40]. The Products Research Group published the fiber properties in January, 1966 [41]. The X-101 fiber was evaluated by the Air Force and found to be somewhat better than Nomex. However, Air Force interest diminished because Nomex was already available [42]. Moreover, new difficulties appeared: ț Du Pont had patented many solvents for polycondensation reactions. Monsanto needed a solvent that was not covered by a Du Pont patent and therefore the scientists were looking for alternatives. When they were unable to come up with anything, Monsanto’s patent lawyers were willing to contest Du Pont’s patent claims. ț Monsanto worked with Hooker Chemical Company to supply the diamine with the preformed amide bonds. However, it was not possible to enter into a price agreement with Hooker. This resulted in a stalemate. In the meantime, the fiber business was deteriorating. In 1967, when a real crisis in the business occurred, Monsanto’s Textiles Division canceled its plans for X-101.

4. Soviet fiber research L.B. Sokolov began the Soviet research on aromatic polyamides. Sokolov worked in Vladimir, 200 km east of Moscow, at the Institute of Synthetic Resins, and was Professor at the local Polytechnic. In 1958, he carried out his first experiments using interfacial polycondensation [43]. He continued this work until his death in the early 1980s, and became the most respected Soviet expert on low temperature polycondensation. E.P. Krasnov, Deputy Director of VNIISV, a large R&D establishment at Kalinin, had been one of Sokolov’s students. In the early 1960s, Sokolov asked Krasnov to develop fibers based on aromatic polyamides that he had made (including MPD-I). Sokolov had given these aromatic polyamides the name Fenilon. Du Pont’s R&D on low-temperature polycondensation gradually became known at the VNIISV. This aroused the interest of the scientists, and the military authorities showed some interest in a fiber with increased thermal resistance. It was suggested by VNIISV scientists that the Soviet Ministry of Chemical Industry (MCI, which commissioned research projects) commission a project on Fenilon, which it did. Two groups began working on the project: one group, headed by A.S. Chegolya, began working on the synthesis of the polymer, and another group started work on the spinning process. At the beginning of the 1970s, when VNIISV scientists were scaling up the process to produce Fenilon, MCI chose to continue its development and terminated a similar research project at the VNIIV17 in Moscow.

17 The VNIIV, at Mytischy near Moscow, was the All Soviet Research Institute for the Fiber Industry. It was part of the Ministry of Chemical Industry. The VNIISV split off from the VNIIV by the end of the 1950s. It was located at Kalinin (nowadays renamed Tver) and dealt especially with nylon and polyester ﬁbers. K.F. Mulder/Technology In Society 21 (1999) 37–61 47

The development of Fenilon applications was a task for institutes that belonged to other ministries. Therefore, the development of end products did not automatically result from the Fenilon pilot plant production. The Central R&D Institute for the Sewing Industry in Kalinin played an important role in developing textile Fenilon applications. Since there were good private contacts with this institute in the same city as the VNIISV, it was not too hard to obtain cooperation. The All-Union Research Institute for cellulose paper production in Leningrad carried out R&D on the production of Fenilon paper for high voltage insulation. In Kalinin, scientists continued studying the production process of Fenilon and optimal ﬁber properties. By the end of the 1970s, MCI was not convinced that it was feasible to build an industrial-scale Fenilon plant as an alternative to buying Du Pont’s Nomex. However, when US President Reagan imposed a ban on Nomex exports to the Soviet Union, the military production ministries urged MCI to secure a supply of Fenilon. A plant was built in Kustanay, in the Kazachstan Republic.18

5. Further Du Pont research

Early in the 1960s, research related to HT-1 gradually began to decrease at Pion- eering. Scientists were looking for other things to work on. Only a few details of HT-1 were still being studied [23]. In 1963 John Griffing was appointed new director of Pioneering. Griffing emphas- ized the study of heretofore intractable polymers. The para-aromatic polyamides were among these. Morgan had made some of these polymers in 1958, but they were thought to be too intractable to be of any interest. In March 1964, a Belgian patent issued to Monsanto’s Preston and Smith was published which claimed the polymerization of an all-para, wholly aromatic polyamide. However, this polymer could not be used to form fibers. At Pioneering, it was decided that Morgan would review his records regarding these polymers. In May, he developed a patent proposal on poly-paraphenylene-terephtalamide that he had once made. (US patent law allows filing a patent within one year of a foreign patent if one can prove that it is based on prior art.) However, support records for the early experiments were meager and therefore Du Pont did not file [12]. In 1963, George Lanzl had given Morgan several months off from his regular work in order to write a book on the 1950s solution polycondensation research [44]. It was decided to assign Stephanie Kwolek to making these all-para aromatic polyamides. Kwolek worked on her own and reported directly to John Griffing. She started her project in June 1964. First, she tried to synthesize PBA and PPD-T,19 but the intermediate for PBA was hard to make. While PBA was described in the Preston/Smith patent, and the monomer synthesis was described in a 1948 publication

18 Neither the construction of the plant nor its coming into operation in 1985 was published. When I visited the VNIISV in 1990, some interviewees even doubted if they were legally allowed to tell me about the existence of the plant and its site. 19 PBA: poly(para-benzamid); PPD-T: poly(para-phenylene-terephtal-amide). 48 K.F. Mulder/Technology In Society 21 (1999) 37–61 by the University of Montevideo, the monomer was susceptible to hydrolysis and deactivation. Nevertheless, on 14 September, Kwolek produced a high polymer that was even better than the one described by Preston/Smith. Both PBA and PPD-T were hard to dissolve. Concentrated sulfuric acid was not considered to be a viable choice as a solvent. George Lanzl, who regularly visited Kwolek, objected to its use. To break the impasse, Kwolek spun a PBA fiber from concentrated sulfuric acid. The fiber seemed interesting: it was not strong, but it had exceptional tenacity; its modulus was about 400 gpd, which at that time was almost a record for a fiber. By the end of 1964, Kwolek had found a way to dissolve PBA. And when dissolv- ing the polymer, she also noted some unusual observations: the solution was like buttermilk, and it stayed that way even after filtering. The viscosity rose as the polymer concentration increased; however, when the polymer concentration exceeded a certain point, the viscosity decreased again.20 The polymer solution was so unusual that a technician at first refused to spin it. In January 1965, a fiber was spun. This fiber had an unusually high modulus [12]. Kwolek was afraid of making a blunder, so for a while, she did not tell her colleagues about her results [45,46]. When she finally did so, it was clear to everyone that this was probably a result with great potential. At a meeting, the physical chemist Paul Antal suggested that they were dealing with liquid crystals. Nobody at Du Pont had any experience with liquid crystals. A literature search was conducted, quantities of academic work were retrieved, and some patents gathered on the spinning of liquid crystalline polymers. However, no reference was found to liquid crystals based on wholly aromatic polyamides and nobody had predicted high strength/high modulus (HS/HM) fibers [12]. Paul Flory21 came to Pioneering as a consultant to help interpret Kwolek’s data [23]. In the 1950s Flory had predicted that polymers that were completely inflexible (“rigid rod”) would behave differently in solutions when a certain concentration was exceeded [47]. Now these liquid crystal polymers were made and processed into fibers. Some expressed doubts about hiring Flory: he might be working on the subject himself; could he be approached yet not give him too many clues about this highly sensitive subject? Pioneering researcher, John Schaefgen, who had worked with Flory at Goodyear in the late 1940s, approached him as a personal friend [48]. Laboratory director John Griffing and George Lanzl, who had now become research director, were enthusiastic about the fiber, and they sold management on the project [33]. Pioneering continued development of the PBA fiber. In June 1965, it was given the project code PRD-27. The process changed several times, with the result that fiber characteristics jumped. It was possible to reach a modulus of 1200 gpd and strengths of 20 gpd. A heat-treated version of this fiber, which was even stronger and had a higher tenacity, was given the code PRD-49. Stephanie Kwolek was assigned to

20 Normally, viscosity only goes up (the solution becomes less fluid) as the polymer concentration increases. 21 Flory had worked at Du Pont before World War II, but lost contact when he worked at the Mellon Institute. He left Mellon to join Stanford University in 1961. K.F. Mulder/Technology In Society 21 (1999) 37–61 49 further study PBA and similar polymers. As the intermediate for PBA was difficult to synthesize, a second project was started which aimed at making other rigid rod polymers.22 In November 1965, Paul Morgan assigned Thomas Bair to study PPD-T and similar polymers. Bair succeeded in making Chloro-PPD-T, which was more soluble than PPD-T. The Chloro-PPD-T fiber had properties that were not as good as the PBA fiber but it was somewhat less expensive. Some time later, Bair also succeeded in spinning PPD-T from highly concentrated sulfuric acid. The properties of these fibers were also less interesting than those of PBA fiber. So, three alternatives had thus far been studied: ț PBA was expensive because of the intermediate, but the development of this fiber was the most advanced and the properties of this fiber could not be attained with other polymers. ț Chloro-PPD-T was developed further because it was somewhat less expensive than PBA. ț PPD-T was much less expensive but could only be spun from concentrated sulfuric acid which nobody liked. Moreover, its properties were not satisfactory. In November 1966, Bair made some progress in spinning PPD-T fibers. In fact, this came about by accident. Bair was working with standard commercial sulfuric acid (96%). When he ran out of the solvent, he obtained more from the analytic laboratory. Suddenly he began achieving amazing results, because it turned out the analytic laboratory was using 100% sulfuric acid. In 100% sulfuric acid, the PPD- T polymer also became liquid crystalline. However, the properties of PPD-T fiber were still less than those of PBA fiber. Harold Mukamal was able to make further progress in 1968. He spun fibers from the polymerization dope which had almost the same properties as PBA fibers. These fibers, however, were rather not uniform in their cross-section, and this problem could only be solved at the expense of fiber strength. Therefore, further studies were made. By mid-1969, polymerization had been further improved. This resulted in such high molecular weights that the polymers could only be dissolved in sulfuric acid. The spinning dopes of PPD-T were very viscous, which limited spinning speed considerably. Fiber properties were within 5% of those of PBA fiber [12]. In the meantime, work on Chloro-PPD-T had also been taken up again. Its polymerization was probably simpler than that of PPD-T; it could perhaps overcome the non-uniformity problems of PPD-T, and would probably be cheap. Much progress was made. It was even possible to produce better fibers than PBA. However, Chloro- PPD-T was rather sensitive to heat treatment. Moreover, one of its monomers showed instability during distillation which would make the process much more expensive. By the end of 1969 a decision had to be taken. There were four alternatives:

22 Kwolek studied the AB type polymers, as opposed to the AABB type that were studied by Mor- gan’s group. 50 K.F. Mulder/Technology In Society 21 (1999) 37–61

1. PBA, 2. PPD-T spun from 100% sulfuric acid, 3. PPD-T spun from its polymerization solution, 4. Chloro-PPD-T. A small breakthrough occurred for the PBA fiber which lowered the costs of the intermediate significantly. As a result, the Chloro-PPD-T project was terminated [49]. Consultants were brought in and the decision was made that PBA was the fiber to commercialize. It was renamed Fiber B, and it was decided to initiate a pre-venture, the first step to commercialization. Mario Cichelli, an engineer, was to head this pre- venture which was scheduled to start in April 1970. The researchers that had been working on PPD-T and Chloro-PPD-T were reassigned to PBA. However, the PPD-T work of one scientist, Herbert Blades was continued. In June 1969, he was assigned to study the basics of the wet spinning process. When he started, a lore had already evolved by which the people were working:

It was just a mysterious art. The ﬁber had a strength of about 10–12 and a modulus of about 500 gpd. That was accepted. Economical speeds could not be reached; they could just reach about 100 yards a minute. In order to be useful, one had to spin at a speed of at least 300 yards a minute, which could not be done.

Blades presented his first results at Pioneering in November 1969. A co-worker, Peter Boettcher, suggested that an air gap between the spinneret and the bath would give improved results.23 Blades reached a breakthrough at the end of 1969. By spinning PPD-T from concentrated sulfuric acid using the air gap spinning method, Blades succeeded in improving spinning speed considerably. In March 1970, when he had his own special mixing equipment to prepare higher solutions of PPD-T in sulfuric acid, he reached amazing results. He spun PPD-T fibers from highly concentrated solutions which had a strength (before heat treatment) as high as 18 gpd.24 These properties could only be matched by PBA if it was spun in the same way. Blades presented these results on 16 April 1970. A new project, PRD-58 was initiated. Since the intermediates for PPD-T were far cheaper than the intermediate for PBA, a PPD-T fiber now seemed to be far more attractive. However, the Fiber B Venture Steering Committee (a joint committee of the manufacturing, technical, and sales divisions of the Textile Fibers Department and the corporate Engineering Department) was well on its way to building a PBA pilot plant and developing applications for this fiber, sometimes in cooperation with customers. Eugene Magat presented the results, but the reception was more or less as a “scientific curiosity”. In particular, the engineers were not willing to give up the pilot plant they had

23 This method had been published on 3 December 1968, in H.S. Morgan’s Monsanto patent. In the Du Pont/AKZO patent litigation case, Du Pont denied having knowledge of this method prior to Blades’ invention. 24 Heat-treated PBA had a strength of about 20 gpd. K.F. Mulder/Technology In Society 21 (1999) 37–61 51 designed: “Part of the problem there was the NIH, Not Invented Here, syndrome of the engineers” [16]. Harry Corey of the Cost Analysis Group made some cost calculations. These showed definite cost-performance advantages in PRD-58. Blades and his assistant Chaffee even improved their fibers. Twelve researchers worked on a process to make a PPD-T fiber according to Blades’s results. In August, the Fiber B Steering Commit- tee agreed on a comparison between PRD-58 and Fiber B. In October 1970, a decision was made to switch to PRD-58. By November 1970, PRD-58 was taken over by Cichelli’s pre-venture [12].

Everything had to be changed, the polymer composition, the whole spinning process. The equipment that had been specially designed went out the window. The site where we had been spinning became unsuitable. It took a complete rethinking from the very ﬁrst brick when we made that change [49].

At the time that the decision was taken, Du Pont had given samples of PBA fiber to Goodyear and others. This had become known in the trade as Fiber B. In February 1970, J.W. Hannell of the Industrial Products Research Laboratory, which had been designing and developing Fiber B tires, announced that Du Pont would introduce Fiber B. He stated that this fiber was especially suited for the reinforcement of high- performance tires. It was possible to make high-performance bias ply tires that gave a much softer ride than the steel-reinforced radial tires [50,76]. Although Hannell did not disclose the fiber’s polymer, many competitors soon found out that it was PBA.25 No PRD-58 was taken out until April 1971, after patents had been filed. In the summer of 1971, B.F. Goodrich scientists disclosed the existence of an “improved Fiber B”.26 This improved Fiber B was PRD 58, the air gap spun PPD-T. By the end of 1973, Du Pont’s pilot plants had produced over 1 million pounds of fiber. To sell the new fiber, it was given a real trademark: Kevlar.

6. Monsanto

Besides developing the heat-resistant fiber X-101, the Monsanto scientists in Dur- ham were looking for fibers with even better heat resistance. In 1963–64, Huffman’s research group studied all-para, wholly aromatic polyamides by using the X-101 approach, i.e., using aromatic diamines that contained amide bonds. A fiber was made which had a remarkably high modulus. To improve its properties, the scientists proposed to spin it from sulfuric acid. However, the head of the department rejected this as being too expensive; he also believed that Celanese had tried this method

25 Almost all the interviewed scientists in Du Pont’s competitors, except for the Russians, said they had heard rumors about Fiber B before. 26 The first Fiber B had a tenacity of 12 g/denier; improved Fiber B had 18 g/denier [51]. Later 20– 22 g/denier was reported [52]. 52 K.F. Mulder/Technology In Society 21 (1999) 37–61 earlier without success. Moreover, heat resistance was important, whereas improved mechanical properties were not a research target. However, Monsanto scientists came across an HS/HM fiber a second time. In the summer of 1966, the laboratory was reorganized. Bruce Black became manager of polymer science in the same department as his friend, Jack Preston. Together, they discussed making heat resistant fibers containing oxadiazole units by a new approach: they would first make polymers containing hydrazides, then form a fiber, and finally heat the fiber to convert the hydrazides to oxadiazoles.27 When the first spinning of such a polymer was done, the as-spun fiber (before converting hydrazides to oxadiazoles) showed extremely high modulus and strength.28 Black and Preston agreed to forget about heat resistance; now the focus would be HS/HM fibers such as tire cord, reinforced composites, and so forth. The project was given the name X-500. However, their manager did not want to pay for the expensive spinning experiments that had to be carried out. The fiber could probably be produced rather cheaply, but it was uncertain whether the specific combination of strength and modulus that was needed for a normal tire cord could be reached.29 Moreover, the fiber business was deteriorating. R&D budgets were being cut, and some scientists were looking for new jobs. Because of tighter budgets and doubtful prospects for developing an X-500 tire cord, Monsanto’s Textiles Division management did not want to invest in a large-scale development project for X-500. The 1967 crisis in the US fiber market considerably affected the X-500 project. The Durham laboratory was virtually taken over by St Louis. Like all R&D projects, X-500 was presented to the Monsanto New Enterprise Division. Engineered com- posite systems were one of the five main activities which this division tried to establish. There was never any doubt that X-500’s prospects for reinforcing composites were very good. It was decided that X-500 would be developed for this division. However, the Durham scientists would no longer study related polymers. X-500 was the product and it had to be developed as fast as possible. In June 1967, the development of X-500 started in earnest. A pilot plant was built in Pensacola, Florida. At the end of 1967, it began to make large quantities of X- 500 fiber. Much of the evaluation was done internally. Pre-pregs to be used in composites were made and tested. The US Army Natick Laboratories tested X-500 for ballistic protection.30 And actions were taken to secure a sound patent position. However, opposition to the X-500 project was gradually growing. Most people at the Textiles Division were used to being second to Du Pont: “The general opinion was that it was good being second. We, as scientists, sometimes tried to be better

27 This idea was patented almost simultaneously by Ashland Oil & Refining Co [53]. There were some strange rumors concerning the cause of this simultaneity. 28 After some heat stretching, the strength was 15–16 g/denier and the modulus was more than 500 g/denier. 29 The importance of improved tire cords had grown, due to safety demands and the introduction of radial tires. 30 Some of Natick’s studies were later published [54,55]. K.F. Mulder/Technology In Society 21 (1999) 37–61 53 than Du Pont” [56]. Monsanto had never been first to commercialize a new fiber. “Our marketing people said, ‘How can we possibly market this product? There is nothing like it on the market.’ This made our [scientists] mouth drop open; how could anybody be so stupid. It is exactly what you want–‘nothing like it on the market’” [42]. Scientists who were working on carbon fiber in Monsanto’s Dayton research center did not like this competing project. The research groups devolved into a culture of professional jealousy. In September 1968, one was ready to announce X-500 as a new product. A trademark had been chosen: Fibron 500. The bulletins were ready. Then, suddenly, the whole project was cancelled. The reason? A negative report about Boeing’s interest in the product.

7. Further Soviet research

In Mytishchi near Moscow, Professor Kudryavtsev’s group at the All-Union Research Institute for Artificial Fibers (VNIIV) discovered liquid crystal polymers at the end of 1968. In 1969, a fiber of extremely high modulus and strength was made.31 This fiber was called Vniivlon. In 1970, the scientists published a scientific article on the polymer [57]. In 1971, a further statement on the properties of the fiber was published: Vniivlon’s mechanical properties were unequalled. It could be applied in cables, tire cords, nets and composites [58]. VNIIV management considered its fiber to be a major scientific achievement which could be of great commercial value. Therefore, the VNIIV patent department applied for patents in Western countries [59]. This was unusual because Western patents required a great deal of hard currency. Western corporations, such as Du Pont, Cel- anese and Dow Chemical, objected to these applications. This forced VNIIV to spend even more hard currency to protect Vniivlon. The Ministry of Aviation Industry (Minaviaprom) collaborated with a VNIIV department on the development of a carbon fiber for new lightweight composites in aircraft. When the military became aware of Vniivlon, it showed great interest. Because of this military interest, export abroad became undesirable. Since VNIIV was not quite satisfied with the representation of its interests before the Western patent authorities, it agreed to drop the patent case and to protect Vniivlon by secrecy. Control over this part of VNIIV’s R&D was transferred from MCI to Minaviaprom. Minaviaprom declared the project closed, that is, no results could be published. The properties of Vniivlon were improved further. A decision was made in 1974 to change the name of the fiber to SVM.32 SVM’s mechanical characteristics were superior to those of Kevlar [60]. However, its intermediates were much harder to produce. Since Kudryavtsev’s department worked under Minaviaprom, it had access to well-equipped military establishments which could manufacture these chemicals.

31 The polymer was based on terephtalic acid and 5,4-di-amino-2-phenyl-benzimidazole. 32 Sverchprogibks Visokomodulsyi Material: super strong, high modulus material. 54 K.F. Mulder/Technology In Society 21 (1999) 37–61

Minaviaprom did not impose strong restrictions on R&D budgets. At VNIIV, SVM was seen as an original piece of research of which it could be proud. Minaviaprom could only obtain an HS/HM fiber from VNIIV. Since the beginning of the 1970s there had been a ban on Western exports of HS/HM fibers to the Soviet Union. For the production of SVM, a pilot plant was built in Mytishchi. While working under Minaviaprom, the experienced manufacturers of military equipment, who were under the control of this ministry, could be ordered to work for the project. High-quality equipment, normally only available to the military, could be obtained. Therefore, the pilot plants were built fairly quickly. The pilot plants supplied fibers to the R&D institutes which were developing high-performance composites for aircraft. Moreover, the military developed SVM bulletproof vests.33 Given the military use of SVM, almost no civil high-volume applications, like tire cords or rubber hoses, were developed. Pilot plant scale production units could easily satisfy the military needs, and there was no need to scale up production further [62].

8. AKZO-Nobel

AKZO-Nobel began its research project on strong fibers in 1970. A merger among several Dutch companies and one German company had recently formed the company, and AKZO had now become one of the world’s largest producers of industrial fibers. The researcher who started AKZO’s project on new strong fibers, Dr Leo Vollbracht, knew of Du Pont’s Fiber B project, but he had no idea what the project was about. Herman Mark visited AKZO, and he told Vollbracht that Du Pont was developing a so-called “ladder-polymer”. However, from the Bair/Morgan patent, Vollbracht learned that Du Pont was working on fully aromatic polyamides and that these polyamides looked rather promising for making strong fibers [63]. Other Du Pont patents from this research were still pending. At the end of 1970, Vollbracht and his two assistants began their first experiments. The AKZO patent office thought that the Bair/Morgan patent, like the Kwolek patent which had just been disclosed, would not prevent AKZO from working on aromatic polyamides. The AKZO researchers were primarily attempting to catch up with Du Pont. Du Pont’s announcement that it would introduce Fiber B on the market reinforced the support of the AKZO board for the research project. In 1973, AKZO was just about to produce its own strong aromatic polyamide fiber at laboratory scale. However, the spinning process was still causing problems. Blades’s patents, which had been published by then, showed the solution: the air gap spinning process. The AKZO patent office advised using parts of the process that were described in the Blades patents because of the prior description of the air gap spinning process in Herbert Morgan’s Monsanto patent [64].

33 At the beginning of the 1980s, Du Pont acquired an SVM bulletproof vest from US intelligence. It originated from the Soviet military in Iraq [61]. K.F. Mulder/Technology In Society 21 (1999) 37–61 55

In 1973, AKZO researchers started working on improvements that would place them in a better negotiating position with Du Pont. Vollbracht worked on new solvents for the polymerization process. Through trial and error, he managed to find an alternative to the solvent mixture used by Du Pont. On 21 February 1975, AKZO applied for a patent on their alternative solvent [65]. The worth of the alternative solvent grew enormously when Du Pont discovered, in September 1975, that its HMPA solvent was carcinogenic [66]. Du Pont’s Mitchel had warned his AKZO colleague, Van Berkel, by telephone of the carcinogeneity of HMPA. Van Berkel told him that this would not harm AKZO because AKZO would use an alternative. Du Pont embarked on a crash program to obtain such a solvent. At first there were negotiations about a license agreement. In these negotiations AKZO wanted a worldwide agreement which would enable the company to produce an HS/HM aramid fiber. Du Pont wanted a license for the new solvent but did not want AKZO as a second aramid fiber producer on the market. The negotiations failed, resulting in a conflict. Du Pont tried to block AKZO’s solvent patent application. Du Pont’s key argument hinged on polymerization studies that had been carried out by Sokolov’s institute in Vladimir in the early 1970s. After eight rejections and two refilings, a US patent was issued to AKZO in December 1981 [78]. AKZO came up with yet another process improvement. It had been extremely difficult to make a good PPD-T/sulfuric acid spinning dope. In 1973, board member Van Krevelen produced a report from the AKZO Pharmaceuticals Laboratory which stated that substances mix better in the solid state. Contact with these colleagues was established. PPD-T was mixed with frozen sulfuric acid and then the mixture was heated. This resulted in an excellent spinning dope. Much later AKZO applied for a patent for this invention after it was discovered that AKZO’s aramid fibers had better heat resistance than Du Pont’s Kevlar; this was due to an improved mixing of the spinning solution. AKZO was also able to control the infringement of this invention. Du Pont also objected to this patent application after it was published in 1981 [67,68]. To conclude, Du Pont’s Kevlar and Nomex were extraordinary products, and its creation was a major achievement but it was perhaps not as unique as was thought at Du Pont. In 1968, Teijin announced that it would commercialize a Nomex-like fiber under the trademark Conex [69]. Bayer and Rhoˆne Poulenc brought similar heat-resistant fibers to the development stage: ATF 2000 [70], and Kermel [71]. Besides Vniivlon/SVM and Fibron 500, by 1969 Bayer also had found a way to make a HS/HM aromatic polyamide fiber [72–74].

9. Patent conﬂicts

In 1978, AKZO started preparations for building full-scale aramid polymer and spinning plants. AKZO’s financial situation was not stable, however, and the company had to ask for support from Dutch government agencies. Du Pont reacted by threatening the Dutch government that it would lose the money it would give to AKZO, either as loans or as subsidies. The government asked an independent lawyer 56 K.F. Mulder/Technology In Society 21 (1999) 37–61 to make a report on the patent situation. Also, internal investigations were made on the patent situation. Although difficulties could be foreseen for AKZO, the report concluded that AKZO’s position was strong enough to go forward with production of the aramid fiber [67]. When it became clear that the Dutch government agencies were willing to help AKZO, Du Pont began to carry out its threats. First, Du Pont filed a complaint to a London court in November 1979. Shortly afterward, Du Pont also filed complaints in France. AKZO reacted by contesting Du Pont’s patents in a US court. The patent struggle spread throughout the world. In almost every industrialized country AKZO and Du Pont fought each other’s patents. Both claimed victories. Not surprisingly, they both won the legal battle in their home country. AKZO won its case in The Netherlands and, after some initial problems also won in Germany. In 1986, AKZO’s aramid fiber was banned from the US market by decision of the International Trading Commission. In the same year, the conflict became more and more a US–European trade conflict. As the legal procedures resulted in contradictory verdicts, the politics became more complex and involved. To create a better position for itself in this conflict, Du Pont decided to build a Kevlar spinning plant in Northern Ireland. In June 1987, AKZO’s aramid fiber was banned from the UK, but the ban was lifted in April 1988 and at that time it even became possible that AKZO could ban Du Pont’s Kevlar from the UK. This was a major victory for AKZO because Du Pont was just finishing the construction of its Northern Ireland plant. A ban on Kevlar imports for the UK would mean the US$60 million invested in the Irish plant would be spent in vain. Moreover, Du Pont’s Kevlar was banned by court decision from Germany. Finally, Du Pont had to sign an agreement which made the international aramid fiber market free for both companies. The patent case had cost each company at least US$100 million for legal costs and lawyers’ fees.

10. Analyzing the conﬂicts

“The discovery of the new concept leading to super-high tenacity, super-high modulus fibers is a striking example of a group effort”34. This observation is probably right, although there are more participants in this group effort than Magat identifies. From Wittbecker to Blades, Magat identifies all the Du Pont scientists and research managers who contributed significantly to Kevlar. However, I have shown that in the 1960s, Monsanto, through Herbert Morgan and Jack Preston, made some important contributions as well. In the 1970s, AKZO succeeded in improving upon Du Pont’s process through Vollbracht’s polymerization solvent and Lammers’ preparation of the spinning dope. Others also made minor contributions to the overall development. In addition, various other scientists had

34 Magat [12], who was involved in Kevlar development at Du Pont. K.F. Mulder/Technology In Society 21 (1999) 37–61 57 independently arrived at results that were more or less similar to Du Pont’s. Developing aramid fibers was an international group effort, with Du Pont’s Pion- eering researchers marching in front, but with many other scientists (even beyond those mentioned in this article) contributing to its momentum. There are two reasons why Du Pont’s Kevlar patent position was unsound: ț Some of the inventions, filed in the 1950s, had been described in the open literature and in patent applications, mainly by Du Pont itself. It is highly doubtful if all patent claims of the 1950s regarding para aromatic polyamides were actually based on experimental data. However, as these claims were filed, Du Pont was unable to make the same claims in subsequent patents. ț There were many inventions whose patents described parts of the Kevlar process. All of these small inventions could be claimed to be obvious or “hardly inventive” with regard to published data. Since there had been so many small inventions, it was impossible for Du Pont to file for an all-encompassing patent that would describe the invention of a product as superior as Kevlar. One could conclude that Du Pont’s patent department ultimately undermined its case by filing too much and too early. However, there were reasons for that: with hindsight, one could say that it might have been better to file for an all-encompassing Kevlar patent, but how could anyone know when Kwolek made her extraordinary fibers? Moreover, not filing for patents is risky since Du Pont’s competitors might achieve the same results.

11. Why such a struggle?

At Du Pont, there was, and probably still is, little appreciation for any of the other contributions that were made by scientists outside Du Pont. For years there had been a search for “new nylons” and Kevlar was seen as just such a new miracle of industrial research. Kevlar definitely was the “baby” of Du Pont’s Experimental Station, and this became important when R&D came under attack for being unproductive. Kevlar was the new miracle of R&D and had to be defended as such. In fact, a similar process can be seen at AKZO. Its aramid fiber project acquired a magic that went beyond the actual meaning of the fiber. The aramid fiber was branded as the product for the future of AKZO’s Fibers Division in a period when AKZO was forced to close down about half its fiber plants. For this reason, the project was presented more than once to the unions and the press. Du Pont’s resistance to AKZO entering this market was perceived as a denial of AKZO’s legal rights. In the Dutch press, AKZO’s fight against Du Pont was sometimes pictured as “Tom Thumb fighting the evil giant”. It was these cultural identities, subsequently attached to aramid fibers, that pre- vented reasonable agreement between the adversaries. Withdrawal of demands by one side not only would cause big financial losses but would especially damage the self-image of the corporations as well as their public image. However, continuation of the conflict was deleterious and harmful to both. As 58 K.F. Mulder/Technology In Society 21 (1999) 37–61 long as there was no final settlement, customers feared the uncertainty resulting from the court decisions. The marketing of the Kevlar and Twaron fibers could reach far better results if AKZO and Du Pont would cooperate. The patent conflict also helped competitive third parties to join the aramid fiber market after 1990 when most of the Du Pont patents expired. In court sessions much information, which was not presented in the patents themselves, was disclosed and there were many interested experts. In fact, this patent conflict was a classic form of the prisoner’s dilemma. The best way to solve the dilemma would have been by mutual confidence, but between AKZO and Du Pont there was very little of that. The events in the struggle between AKZO and Du Pont more or less became autonomous. Because these companies have been adversaries for years, many people have developed an image of one party or the other as the “absolute evil”. At the end of the 1980s, most people at AKZO’s Textile Fibers Department thought of Du Pont as “the company that intimidated others with a bundle of phony patents and was probably capable of committing various offenses to prevent fair competition”. At Du Pont, the general view of AKZO was that “this company tried to steal Du Pont’s invention”. On both sides, dubious rumors were spread about attempted brib- ery, espionage, and other criminal offenses. It is hardly surprising, then, that the hostilities continued even after a worldwide settlement on the patent issue was reached in May 1988. By July 1992, Du Pont had filed a “dumping petition” against AKZO, in which it complained that AKZO was selling its Twaron fiber too cheaply in the US.35 Du Pont was successful in its dumping claim: in August 1995, the US International Court of Trade turned down AKZO’s appeal against earlier rulings in favor of Du Pont. It sometimes seems as if the hostilities will continue forever.

References

[1] Slind-Flor V. $253 million jury verdict overturned, court ﬁnds no patent infringement by Nintendo. The National Law Journal, 25 November 1996:B-1. [2] Anonymous. Who owns Polypropylene? and Phillips ﬁnally wins its patent. Chemical Week, 23 March 1983:13–4. [3] McMillan, FM. The chain straighteners. Houndmills: MacMillan, 1979. [4] Furukawa, Y. Staudinger, Carothers and the emergence of Macromolecular Chemistry. Ph.D. disser- tation, University of Oklahoma, 1983. [5] Hermes ME. Enough for one lifetime: Wallace Carothers, inventor of nylon. Washington: American Chemical Society, Chemical Heritage Foundation, 1996. [6] Stahl GA. Herman F. Mark: the continuing invasion. In: Stahl GA, editor. Polymer science overview, a tribute to Herman F. Mark. Washington (DC): American Chemical Society, 1981. [7] Boyer RF. Herman Mark and the plastics industry. Journal of Polymer Science 1966;C12:111–8. [8] Mark H. Transcripts of interviews conducted by James J. Bohning and Jeffrey L. Sturchio at Brook-

35 This is probably caused by a difference in marketing strategies. AKZO wants to sell its Twaron with low proﬁt margins to achieve market growth. It therefore expanded production capacity in 1993. Du Pont, however, is selling Kevlar at the price level of a specialty. K.F. Mulder/Technology In Society 21 (1999) 37–61 59

lyn Polytechnic February 3, March 17, and June 20. Philadelphia: The Beckman Center for the History of Chemistry, 1986. [9] Seymour RB, editor. Pioneers in polymer science. Dordrecht/Boston/London: Kluwer Academic Publishers, 1989. [10] Mueller WF. The origins of the basic inventions underlying Du Pont’s major product and process innovations, 1920 to 1950. In: National Bureau of Economic Research, The rate and direction of inventive activity: economic and social factors. Conference proceedings. Princeton (NJ): Princeton University Press, 1962. [11] Hounshell DA, Smith JK. Science and corporate strategy: Du Pont R&D, 1902–1980. Cambridge: Cambridge University Press, 1988. [12] Magat EE. In the pursuit of strength–the birth of Kevlar. Manuscript: Eugene Magat, 109 Forest Drive, Chapel Hill (NC 27514), 1996. [13] Krammer A. Technology transfer as war booty: the U.S. technical oil mission to Europe 1945. Technology & Culture 1981;22:68–103. [14] Smith LH. Synthetic fiber development in Germany. New York: Textile Research Institute, 1946:700–10. [15] Wittbecker EL, Morgan PW. Interfacial Polycondensation I. Journal of Polymer Science 1959;XL:289–97. [16] Blades H. Interview conducted by Karel Mulder, Wilmington, Deleward, 8 November 1989. [17] Morgan PW. Interview conducted by Herman Skolnik at West Chester, Pennsylvania, March 15, 1986. Philadelphia: The Beckman Center for the History of Chemistry, 1986. [18] Morgan PW, Kwolek SL. The nylon rope trick: demonstration of condensation polymerization. Jour- nal of Chemical Education 1959;36(4):182–4. [19] Hill HW, Kwolek SL, Sweeny W. US patent 3.094.511, assigned to Du Pont, application 17 Nov- ember 1958 (1963). [20] Morgan PW. Interview conducted by Karel Mulder, Wilmington, Delaware, 8 November 1989. [21] Kwolek SL, Morgan PW, Sorenson W. US patent 3.063.966, assigned to Du Pont, 1962. [22] Hounshell DA. Du Pont Kevlar Aramid Industrial Fiber. Boston, MA: Publishing Division, Harvard Business School, 9-391-146, 1991. [23] Kwolek SL. Interview conducted by Karel Mulder, Wilmington, 8 November 1989. [24] Hagley Museum, accession number 1771, box 43. [25] Ross JH. High temperature fiber research. Textile Research Journal, September 1962:768–77. [26] Carr WHA. The Du Ponts of Delaware. London: Frederick Muller Limited, 1965. [27] Stinson S. Herman Mark wins Perkin Medal. Chemical & Engineering News, 3 March 1980:30. [28] McMillan FM. The chain straighteners. Houndmills: MacMillan, 1979. [29] Anonymous. Chemical & Engineering News, 15 September 1958. [30] Morgan PW. Low-temperature solution polycondensation. Journal of Polymer Science 1963;4:1075–96. [31] Morgan PW. Interview conducted by David Hounshell and John K. Smith, 16 October 1985. Hagley Museum & Library, Wilmington, DE, 1985. [32] Schnell H. Polycarbonate, eine Gruppe neuartige thermoplastische Kunststoffe. Angewandte Chemie 1956;68(20):633–60. [33] Morgan PW. Development of low temperature polycondensation processes and aromatic polyamides. Journal of Polymer Science 1985;72:27–37. [34] Forrestal DJ. Faith, hope and $5.00: the story of Monsanto, the trials and triumphs of the first 75 years. New York: Simon and Schuster, 1977. [35] Huffman WA, Smith RW, Dye WT. US patent 3.203.933, assigned to Monsanto, 31 August 1965. [36] Preston J, Smith RW. Belgian patent 637.260 assigned to Monsanto, application 11 September 1962 (1964). [37] Abshire CJ, Marvel CS. Some oxadiazole and Triazole Polymers. Die Makromolekulare Chemie, 1961:388–97. [38] Morgan PW. Condensation polymers: by interfacial and solution methods. New York: Interscience Publishers, 1965. 60 K.F. Mulder/Technology In Society 21 (1999) 37–61

[39] Preston J, Smith RW, Stehman CJ. Aromatic ordered copolyamides for temperature resistant fibers. Journal of Polymer Science 1967;19:7–15. [40] Preston J, Dobinson F. New high temperature aromatic polyamides. Polymer Letters 1964;2:1171–4. [41] Weiss JO, Morgan HS, Lilyquist MR. A new high temperature fiber, its properties and performance. Journal of Polymer Science 1967;19:23–39. [42] Preston J. Interview conducted by Karel Mulder, Raleigh, NC, 10–12 November 1989. [43] Sokolov LB, Gudakova TV. USSR patent 121.934, issued 18 August 1959. [44] Morgan PW. Condensation polymers by interfacial and solution methods. New York: Inter- science, 1965. [45] Kwolek SL. Liquid crystalline polyamides. The Chemist, November 1980:9–12. [46] Smith L. Miracle in search of a market. Fortune, 1 December 1 1980:92–6. [47] Flory PJ. Phase equilibria in solutions of rod-like particles. Proceedings of the Royal Society 1956;234:73. [48] Schaefgen JR. Interview conducted by Ferguson RC, Wilmington, DE, 3 April 1986. Philadelphia: The Beckman Center for the History of Chemistry. [49] Fitzgerald JA. Interview conducted by Karel Mulder, Wilmington, DE, 8 November 1989. [50] Hannell JW. Tire cords. Polymer News 1970;1:8–13. [51] Lee ZS, Skolnik L, Draves CZ. Survey of cord candidates for radial belts. Rubber World, July 1971:43n. [52] Wilfong RE, Zimmerman J. Future organic tire fibers. Journal of Applied Polymer Science 1973;17:2039–51. [53] Culbertson BM. US patent 3.389.122 assigned to Ashland, 18 June 1968, application 18 May 1966. [54] Laible RC, Figucia F, Ferguson WJ. The application of high modulus fibers to ballistic protection. Journal of Macromolecular Science-Chemistry 1973;7(1):295–322. [55] Laible RC, Figucia F, Kirkwood BH. Scanning electron microscopy of high speed fiber impact phenomena. Applied Polymer Symposium 1974;23:181–91. [56] De Winter W. Interview conducted by Karel Mulder, 18 September 1990, Mortsel, Belgium. [57] Kudryavtsev GI. Thermal stability of aromatic polyamides and polyimides. Vysokomolekulyarnye Soedenii 1970;12(10):2205–10. [58] VNIIV. The Superhigh-Tenacity Fiber Vniivlon N. Chemical Fibers. UNIIV: Khimisheskie Volokna, 1972:106–7. [59] Tokarev AV et al. Deutsches Offenlegungsnummer 2.208.811, assigned to VNIIV, application 24 February 1972 (1973). [60] Kudryavtsev GI. Ultrastrong high modulus synthetic fiber SVM. Chemical Fibers 1974;6:70–1. [61] Yang HH. Verbal comment during ACS meeting, Atlanta, 1991. [62] Mytishchy. Various interviews, August 1990. [63] Vollbracht L. Interview conducted by Karel Mulder, Arnhem, 5 January 1988. [64] Sieders R. Interview conducted by Karel Mulder, Arnhem, 16 December 1987. [65] Chemical Abstracts vol. 85, no. 160859v. [66] Zapp JA. HMPA, a possible carcinogen. Science 1975;190:422. [67] Weijland H. Interviews conducted by Karel Mulder, Arnhem, 14 January 1988; 12 December 1988; 16 February 1989; 12 March 1991. [68] Lammers HT. European patent application 21.845, assigned to AKZO, application 8 June 1979 (1981). [69] Anonymous. Cemical & Engineering News, 13 and 20 October 1969. [70] Von Falkai B. Herstellung und Eigenschaften von aromatisch-heterocyclischer Polyamidfasern. Lenzinger Berichte, February 1974;36:48–55. [71] Pigeon R, Allard P. Hitzebesta¨ndige und flammfeste Fasern. Angewandte Makromolekulare Chemie 1974;40,41:139–58. [72] Von Falkai B. Interview conducted by Karel Mulder, Dormagen, 2 December 1988. [73] Ku¨nzel H. Interview conducted by Karel Mulder, Dormagen, 2 May 1989. [74] Ku¨nzel HE et al. Soluble aromatic polyamides for making high elasticity-modulus fibers. Deutsches Offenlegungsnummer 2.144.126 assigned to Bayer, application 3 September 1971 (1973). [75] Scnell H. Chemistry and physics of polycarbonates. New York: Interscience Publishers, 1964. K.F. Mulder/Technology In Society 21 (1999) 37–61 61

[76] Anonymous. Chemical & Engineering News, 2 February 1970, 2 September 1970. [77] Flory PJ. Principles of polymerchemistry. Ithaca: Cornell University Press, 1953. [78] United States Court of Appeals for the Federal Circuit. Petition by Appelants for Rehearing and Suggestion for Rehearing in Banc. Appeal No. 86–1327.

Karel Mulder is a lecturer in Technology Assessment at Delft University of Technology. He also heads the Technology and Society Department of the Royal Dutch Institute of Engineers (KIVI). Mulder received an engineering degree from the University of Twente and received his Ph.D. in Management Studies from Gron- ingen University in 1992 on a historic study of research strategies. His research interests include the historic and sociological analysis of innovations in the chemical industry.