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Mark, Herman F.

MARK, HERMAN F.

(b. Vienna, Austria, 3 May 1895; d. Austin, Texas, 6 April 1992),

chemistry, polymer chemistry, molecular structure, education.

Mark was cited in a memorial program after his death as one who had “earned a lasting place in the history of polymer science through his research contributions, the successes of his students, his organizational genius, and his timeless promotion of polymer science. It is entirely accurate to say that Mark found polymers a curiosity and made them a science.” Linus Pauling, while admitting that most chemists thought of Mark as a polymer pioneer, stressed that he thought of Mark “with affection and admiration, as a pioneer in modern structural chemistry and an important early contributor to its development” (Pauling, 1984, p. 337).

Early Life . This dichotomy is further emphasized by the two distinct phases of Mark’s life—the years he spent in Europe and the years he spent in Canada and the United States. Born in Vienna, Mark was the oldest of the three children of Hermann Carl and Lili Mueller Mark. (He originally spelled his own name “Hermann,” but dropped the final “n” when he emigrated.) His father was a surgeon, a graduate of the Viennese School of Medicine, who spoke four languages fluently. Mark recalled in his autobiography that his early years up to his graduation from high school were a mixture of the discipline exacted by his parents when it came to school work and the freedom that ensued after that work was completed.

Mark filled his spare time with sports of all kinds, especially soccer and tennis, with skiing and skating occupying the winter months. As amateur musicians his parents instilled in him a love of music that was further bolstered by exposure to the Viennese music scene of world-class orchestras, operas, and plays. His interest in science was first implanted by Franz Hlawaty, his teacher in mathematics and physics, who made these traditionally hard subjects clear with his lucid explanations of principles and applications. It was further nurtured by a close high school friend, Gerhardt Kirsch. Four years older than Mark, Kirsch enrolled at the University of Vienna after graduation and took Mark, still a high school student, to hear lectures by such luminaries as Emil Fischer, Albert Einstein, Ernest Rutherford, and Marie Curie. At home, some of his father’s classmates at the university, including Sigmund Freud, came to dinner. Listening to discussions between his father and some Zionist friends about Theodor Herzl and Chaim Weizmann, Mark became aware of potential changes in politics and culture, not realizing that his own idyllic youthful existence was soon to change.

Military Service and Education . Graduating from high school in 1913, Mark opted to get his required military service out of the way immediately by volunteering for a one-year stint, intending to start at the university in 1914. As a member of a mountain infantry regiment in the Austrian-Hungarian army, Mark was close to completing his year of service when World War I broke out. Mark served on the Russian and Italian fronts, rising to rank of lieutenant. He was wounded three times and received fifteen medals, including one of Austria’s highest awards for bravery. In September 1914, Mark was sent home to recuperate from a serious leg wound and managed to complete one semester of graduate study in chemistry before he returned to the Austrian-Italian front. The war dragged on for three more years, and in 1918 Mark’s unit was captured by the Italians. He spent the next eleven months as a prisoner of war in Monopoli.

Finally returning to Vienna in 1919, Mark immediately resumed his studies in chemistry with Wilhelm Schlenk and received his PhD in organic chemistry in 1921. In an oral history interview Mark said Schlenk was an attractive teacher whose techniques Mark adopted in his own career—“be very simple, make experiments, address the people visually and personally, and then always tell a few interesting stories in between. Don't make it too dry” (1986, p.1)

Molecular Structure Research . When Schlenk moved to the University of Berlin in 1921, Mark went with him as one of his assistants. Here he continued his research on trivalent carbon, which had been the subject of his PhD thesis, but within a short time Schlenk introduced him to Nobel laureate Fritz Haber, who was organizing a research institute on fiber chemistry within Kaiser Wilhelm Gesellschaft, the so-called Kaiser Wilhelm Institut für Faserstoffchemie. Haber explained why he needed an organic chemist with an interest in physical chemistry, and Mark quickly accepted the offer because “it was a new horizon and a big new institute with a lot of money” (Mark, 1986, p. 4). In August 1922 Mark married another Viennese, Marie Schramek, and they started their life together in a one-room apartment in Dahlem, a Berlin suburb.

The fiber research group was charged with improving the synthetic rayon fiber that the Germans made from cellulose because this rayon could not compete with natural fibers such as cotton and wool being used in other European countries. Told by institute director Reginald Oliver Herzog to determine the structure of rayon and cotton and cellulose with x-ray diffraction, Mark’s group, headed by Michael Polanyi, embarked on a remarkable series of experiments. Because x-ray diffraction was a new technique, they constructed their own instrument with the assistance of other institutes in physics and physical chemistry. According to Polanyi, “Mark’s experimental skill bordered on genius” (Morawetz, 1985, p. 593).

Because “you don't start climbing Mount Everest before you have climbed a large number of other peaks” (Mark, 1986, p. 5), Mark’s group started by using x-rays to determine the structure of tin and zinc, progressing through inorganic compounds to larger organic compounds, and finally cellulose and rubber. Over the next four years more than fifty papers detailing their results brought considerable recognition to Mark’s group. Einstein visited Mark’s laboratory on a number of occasions and asked him to use their equipment to verify the Compton effect, which was crucial to Einstein’s work, then being questioned by William Duane at Harvard because he could not repeat Compton’s work. Mark’s work was the first independent confirmation of the Compton effect, which pleased Einstein greatly.

Mark’s work placed him in the middle of the ongoing controversy about whether natural fibers were large molecules, as claimed by Hermann Staudinger, or whether their properties could be explained by colloid chemistry. In the end, the conclusions from the work on fiber formers were simple enough. They all consisted of long-chain molecules with molecular weights above 100,000. Some had a regular structure and could crystallize, while others could not. They all behaved like organic substances with respect to stereochemistry, composition and reactivity of functional groups. Most of their properties could be understood with covalent bonding along the chains and the van der Waals interactions between them.

I. G. Farben . In the summer of 1926 Haber introduced Mark to Kurt H. Meyer, a member of the board of directors of the German chemical company I. G. Farben. It was a repeat of the meeting Mark had with Haber four years earlier, only this time Mark was told that I. G. Farben was actually making fibers such as cellulose acetate and rayon that Mark had been studying from the loftier academic viewpoint. But the problem was still the same—the synthetics had a beautiful luster and were easily dyed, but they could not compete with the natural fibers on wet strength and abrasion resistance. I. G. Farben was setting up a fundamental fiber research laboratory, and they wanted Mark to work there, applying what he had learned in Berlin to help the company. They essentially wrote Mark a blank check, and he accepted, on the condition that he could do some fundamental research as well.

For the next six years, first as group leader and then as assistant research director, Mark produced another series of highly important papers on the chemistry of large molecules, including fiber structure, fiber spinning, synthetic rubber, and plastics. Applying fundamental studies to a technologically important problem, Mark showed that his crystallographic data could be used to predict the strength of an ideal fiber where it is only the breaking of covalent bonds that leads to mechanical failure.

At the same time, Mark and his assistant Raimund Wierl had discovered that the structure of gas molecules could be determined by studying their diffraction of a beam of electrons. In 1930 Mark showed the results to the visiting Linus Pauling, who later admitted that he could not contain his enthusiasm as he realized the impact of the discovery. Mark told Pauling he was not going to continue this work and gave Pauling the plans of the apparatus. When Pauling returned to California he constructed an instrument and over the next twenty-five years used it to determine the structure of 225 different substances that were crucial to his work in structural chemistry. Pauling was forever grateful to Mark not only for discovering the technique, but especially for Mark’s generosity in sharing it with him.

By 1932 Mark had established himself as a gifted experimentalist who had made significant contributions to the structure of molecules and whose results were placing the fledgling concept of polymers on a firmer footing, as evidenced in part by the publication in 1930 of a handbook on polymer chemistry coauthored by Mark and Meyer.

Mark once said there were three main turning points in his life, and none of them was planned. The first was his meeting with Haber in 1922, the second was his meeting with Meyer in 1926, and the third was a meeting with I. G. Farben board member Wilhelm Gaus in 1932. According to Mark, Gaus told him bluntly that the company expected Adolf Hitler to gain power in Germany in the near future and that if he did, employment conditions would probably change although they could not predict how at the moment. Gaus projected that because Mark was a foreigner with a Jewish father, he might face difficulties beyond the company’s control in the future. Because Mark had an excellent reputation in academic circles and had published widely, Gaus suggested that Mark look for a university position (Stahl, 1981, p. 66; Mark, 1986, p. 28).

Academic Program in Polymers . Mark found a haven in his native Vienna, where in 1932 he accepted an appointment as a professor of physical chemistry and director of the first chemistry institute at the University of Vienna. Mark set as his goal the organization of an institute for polymer research and education. With the assistance of some capable people Mark completed the task by 1936, when a new curriculum was in place to produce a polymer chemist.

Because he knew that industry was heavily involved in polymer synthesis, Mark decided instead to focus his research on the kinetics and the mechanism of polymerization reactions. Mark’s efforts to establish a new program in polymer chemistry soon became well-known and attracted many students, some even from Russia. The chemical industry also made it clear that they were interested in hiring the graduates from Mark’s program.

Mark’s research on polymers continued unabated in Vienna, although now viscosity measurements, osmotic measurements and diffusion measurements replaced x-ray diffraction, and his papers were more theoretical in nature. During this very productive time he published more than seventy research papers and six books. In addition to looking at the mechanism of polymer formation in solution, Mark and his coworkers also focused on solution viscosity and its application to polymer systems. One important result was the Mark-Houwink equation, conceived by Mark and Roelof Houwink independently about the same time. Although it was semiempirical and unsophisticated, it was used for more than four decades to determine the approximate viscosity-average molecular weights of linear polymers and it still finds important applications in polymer chemistry today. Mark also collaborated with Eugene Guth in formulating a statistical theory of the elasticity of a flexible chain molecule, another important contribution from his Vienna years.

Now that his reputation as a polymer chemist was firmly established, Mark also needed to ensure the success of his institute in Vienna by securing funding from the chemical industry, primarily in England, publicizing it through lectures given throughout Europe and Russia, and attending scientific meetings in many different countries. All of this helped solidify his institute and Mark himself as a leader in the new science of polymer chemistry.

Escape to Canada . In the midst of deteriorating political conditions in Austria, Mark received a letter from Carl B. Thorne, the managing director of the Canadian International Paper Company in Montreal in May 1937. Noting Mark’s work with cellulose, Thorne explained that “our lifeblood is cellulose.” Thorne was concerned that their research laboratory was becoming obsolete because both the customers and the competition were becoming more sophisticated. Thorne wondered if Mark would be interested in becoming the research director of his paper company.

When Thorne came to Europe that summer, he cabled Mark and asked to meet in Dresden. Thorne repeated his offer, but Mark explained that it would not be possible to just walk away from his research institute and his students and never come back. Seeking a compromise, Mark suggested that he might come for a short time to reorganize the laboratory and train the people there in the new polymer techniques. After that, he could make periodic visits as a consultant. But Thorne really wanted a full-time research director, and though interested in Mark’s proposal, he left the meeting with a curt “Let me see what else I can do.”

Mark never realized at the time that this meeting would be his lifesaver after the Germans invaded Austria on 12 March 1938. Mark was arrested the next day and put in a Gestapo prison where he was interrogated about his association with I. G. Farben and Engelbert Dollfuss, a close friend who had served in Mark’s unit in World War I. Dollfuss became the chancellor of the Austrian Republic and vainly tried to keep the country independent of the Nazis until he was assassinated in 1934. After four days Mark was released, but not before his passport was taken and his correspondence with Einstein confiscated.

After his release Mark went to the Canadian embassy and wired Thorne that he was ready to come to Canada. Thorne agreed, and arranged for an official letter of employment. With employment in Canada secured, Mark was able to get a Canadian visa, and with that came visas to pass through Switzerland, France, and England. To get his passport back, Mark appealed to a former schoolmate who was also a Nazi lawyer. It cost Mark a year’s salary in bribes, but eventually the passport was returned.

Unable to withdraw any funds, Mark discreetly purchased platinum and iridium wire, which he shaped into coat hangers. On 10 May 1938, Mark, his wife, two boys, and a Jewish niece who was a prominent harpsichordist mounted a Nazi flag on the hood of their car, strapped skis and other gear to the top of the car, put their clothes on the coat hangers, and drove into Switzerland. Their passage to Canada was almost leisurely, thanks to Thorne who arranged for them to spend the summer in Switzerland, France, and England. Mark used the time in England to do some research on fibers, and even during the transatlantic voyage he worked on finishing the English edition of his Physical Chemistry of High Polymeric Systems. He arrived at the company plant in Hawkesbury, Ontario, on 26 September 1938. Mark would later exclaim, “Canada was heaven. Not only because it was in America, but because it had such a good reputation as a country and as a beautiful country. From then on everything was easy” (1986, p. 36).

Advancing Polymer Science . Mark found the laboratory at Hawkesbury to be the “state of the art cellulose chemistry of the early 1920s.” It took him well over a year to bring the laboratory up to current standards. Much of this was supported and encouraged by du Pont, who was one of Thorne’s best customers. Du Pont was using the wood pulp from the paper company to make a rayon that was a soft and luxurious textile fiber. In 1939 du Pont found that they could also make a rayon that was stronger, harder, and more durable. It was not very good for textile applications, but it made an excellent tire cord. Du Pont called it Cordura. Canadian International’s wood pulp was not suitable for making Cordura, and Mark attacked the problem with his usual enthusiasm. He found that there was a substantial amount of low molecular weight material in the textile rayon, which was good as a plasticizer for extensibility, but was bad for tire cord tensile strength. After removing the low molecular weight material Mark made a number of samples of the new rayon and made Cordura from it. Within a year Mark had worked out all of the details to go from raw pulp to the final pulp that was suitable for Cordura.

In Canada, Mark renewed his contact with Eric S. Proskauer, a publisher of one of his books on polymers in Germany. Proskauer had emigrated to the United States in 1937 and with another émigré, Maurits Dekker, established Interscience Publishing Company. At a meeting in Montreal in 1939 Mark told Proskauer he would probably be returning to academia in the near future, and that it was time to think of resuming publications in polymer science. Proskauer agreed. Because they were both immigrants, it was decided to begin with a volume on someone already established in the United States, and that was Wallace H. Carothers, the du Pont polymer chemist who discovered nylon and neoprene. Because Carothers had committed suicide in 1937, they felt this would be a fitting tribute to his genius. This was the first monograph in “High polymers; a series of monographs on the chemistry, physics and technology of high polymeric substances” that spanned more than thirty years and twenty-five volumes.

Brooklyn Poly . After solving the Cordura problem, Mark did not see any exciting problems in the future. To Mark, scaling up the Cordura process was an engineering problem and held no interest for him. When Mark reminded Thorne of a previous discussion in which he had said that he did not want to stay at the paper company forever, Thorne was furious. Thorne recalled how he helped Mark escape the concentration camps, and Mark knew he was in a difficult situation because he did owe his freedom to Thorne. Mark talked to the plant manager, Sigmund Wang, who advised him that the magic word was du Pont. “All you need to appease the boss is the word Du Pont,” Wang said. “If you can convince him that Du Pont would look favorably on your move to the United States to a university which is somehow in contact with Du Pont, he would be agreeable because the whole mill lives from Du Pont” (Mark, 1986, p. 42). Between the two of them they eased Thorne’s anger and opened the way for Mark to leave the paper company.

Through the development of the Cordura process Mark had made several contacts with du Pont people, and eventually made several trips to Wilmington, Delaware. One of those contacts was William Zimmerli, who was on the board of directors of the Polytechnic Institute of Brooklyn (now Polytechnic University). Because of his success on the Cordura project, Mark was recommended by Zimmerli to Raymond E. Kirk, Polytechnic’s chemistry department chair, and Harry S. Rogers, the president, because Zimmerli felt that Polytechnic should become involved with polymers. Mark was given an adjunct professorship that was paid for by du Pont.

Kirk assigned Mark to the Shellac Bureau, a group that tested shellac being imported from India and then bleached it and delivered it to customers. Because the war was interfering with the shellac shipments, and Mark had experience with synthetic resins that mimicked shellac, he was able to help the bureau’s research. But Mark’s vision went far beyond shellac. With Kirk’s blessing, Mark slowly began to develop a polymer program at Polytechnic which in 1946 became the Polymer Research Institute, the first of its kind in the United States.

But the war years saw Mark involved in some unusual projects. Because he had made measurements on the shear strength of snow and published papers on the heavy water content of glaciers, Mark was asked by the U.S. Army to assist in the field tests of a vehicle called the Weasel that would be used for combat in snow conditions. Mark and Turner Alfrey went to the Canadian Rockies where they made measurements relating the snow shear strength to the composition, and the slope angle under which the Weasel could maneuver.

This was so successful for the use of the Weasel in northern Europe that the army enlisted Mark’s aid on the Ducq, an amphibious landing craft. Mark and Alfrey were able to determine the conditions under which the Ducq could be safely released from transport ships. Another wartime project was the so-called floating landing strip where the addition of a small amount of wood pulp to ice reduced its brittleness. The results have been used ever since in the construction of roads, air strips, bridges, and habitats in Arctic areas.

Polymer Research Institute . Toward the end of the war Mark turned his attention back to Brooklyn, where he intended to make the Polymer Research Institute a group with an international reputation. He also planned to initiate and sponsor the founding of similar institutions that would constitute a network of polymer research centers cooperating closely with each other. To this end Mark headed the planning committee of the Chaim Weizmann Institute of Science in Israel and maintained a lifelong association with that organization.

Mark served as director of the Polymer Research Institute until 1964, when he became emeritus. With his exceptional organizational skills he developed a curriculum, hired faculty, and began a research program. When the research began paying dividends Mark found that submitting papers to traditional journals resulted in a cursory dismissal with the explanation that the journal did not publish polymer papers. Undaunted, Mark founded the Journal of Polymer Science. New courses meant that new textbooks and reference works were needed, and they were quickly produced and published by Interscience. There were seminars and symposia, drawing people to Brooklyn and showcasing the developing polymer program there. And the tireless Mark was everywhere he could be, giving papers at scientific society meetings, industrial venues, and academic departments. In essence, Mark became the spokesperson for polymer science. He organized a special issue of Scientific American on polymers in which he wrote the lead article. He was profiled in the New Yorker under the title “Polymers Everywhere,” and the New York Times carried articles about him for more than forty years, including the announcement of his receiving the National Medal of Science from President Jimmy Carter in 1979.

Graduates of the Polymer Research Institute had no difficulty finding jobs, not in academia, necessarily, but in the chemical industry, which was exploiting this new science to make new products that would impact almost every facet of daily life. And those who did maintain academic careers often set up their own polymer centers that produced more research and more experts in the field.

Mark remained active long past his obtaining emeritus status, and was noted for always looking ahead to the future of his science. For example, in the 1980s he led a study of fire-resistant polymers used in public places. Mark received many tributes to his scientific prowess, including numerous honorary degrees and medals. Polymer chemist Raymond Boyer explained that Herman Mark’s contributions to the American plastics industry “has been immeasurable because it had so many primary and secondary effects of a highly ramified nature on all phases of polymer activity in the United States” (Boyer, 1966, p. 111), and Sir Eric Rideal noted succinctly that “there are no workers in the world in polymer science who at some point in their investigations are not indebted to his pioneering work” (Stahl, 1981, p. 80). Mark died after a brief illness at the home of his son, Hans Mark, chancellor of the University of Texas, at the age of ninety-six.

BIBLIOGRAPHY

WORKS BY MARK

With Hartmut Kallmann. “Über einige Eigenschaften der Compton-Strahlung” [Some properties of Compton radiation]. Naturwissenschaften 13 (1925): 1012–1015.

With Kurt H. Meyer. Der Aufbau der hochpolymeren organischen Naturstoffe [The structure of high molecular organic natural substances]. Leipzig, Germany: Akademische Verlagsgesellschaft, 1930.

With Eugene Guth. “Zur Statistchen Theorie der Käutschukelastizitat” [On the statistical theory of the elasticity of rubber]. Zeitschrift fur Elektrochemie 43 (1937): 683–686.

The General Chemistry of High Polymeric Substances. New York: Elsevier, 1940.

Physical Chemistry of High Polymeric Systems. New York: Interscience Publishers, 1940.

With George S. Whitby. Collected Papers of Wallace H. Carothers on Polymerization. New York: Interscience Publishers, 1940.

With Arthur V. Tobolsky. Physical Chemistry of High Polymeric Systems. 2nd ed. New York: Interscience Publishers, 1950.

“Giant Molecules.” Scientific American 197 (March 1957): 80–89.

Giant Molecules. New York: Time, 1966.

“Polymer Chemistry: The Past 100 Years.” Chemical & Engineering News (6 April 1976): 176–189.

“The Planning of the Weizmann Institute.” Rehovot 9, no. 1 (1980): 3–7.

“Polymer Chemistry in Europe and America—How It All Began.” Journal of Chemical Education 58 (1981): 527–534.

Interview by James J. Bohning and Jeffrey L. Sturchio at Polytechnic University, Brooklyn, New York, 3 February, 17 March, and 20 June 1986. Philadelphia: Chemical Heritage Foundation, Oral History Transcript #0030.

From Small Molecules to Large: A Century of Progress. Washington, DC: American Chemical Society, 1993. This autobiographical work is part of the series, “Profiles, Pathways and Dreams,” edited by Jeffrey I. Seeman.

OTHER SOURCES

Boyer, Raymond I. “Herman Mark and the Plastics Industry.” Journal of Polymer Science, Part C 12 (1966): 111–118.

Ginsberg, Judah. “The Geheimrat.” American Chemical Society. Available from http://acswebcontent.acs.org/landmarks/landmarks/polymer/pol_5.html.

Hunt, Morton M. “Polymers Everywhere.” New Yorker 34 (1958): 13 September, 48–50; 20 September, 46–79.

Morawetz, Herbert. “Herman Mark—A Legend in His Lifetime.” Unpublished typescript, oral history transcript #0030, research file, Chemical Heritage Foundation, Philadelphia. This research file is rich in other resources on Mark, including photocopies of New York Times articles taken from Mark’s 85th birthday scrapbook.

_____. “Herman Mark, ‘The Geheimrat’ at 90.” Macromolecules 18 (1985): 593–594.

Pauling, Linus. “Herman Mark and the Structure of Crystals.” Chemtech (June 1984): 334–337.

Program for “Polymers to the Year 2000 and Beyond, a Memorial Symposium for Herman F. Mark.” Polytechnic University, Brooklyn, New York, 9 October 1992.

Proskauer, Eric. “A Tribute to Dr. Mark.” Journal of Polymer Science, Part A: Polymer Chemistry 26, no. 9 (1988): vii–ix.

Saxon, Wolfgang. “Herman F. Mark Dies at 96; A Pioneer in Polymer Chemistry.” New York Times, 10 April 1992.

Stahl, G. Allen, ed. Polymer Science Overview: A Tribute to Herman F. Mark. Washington, DC: American Chemical Society, 1981.

James J. Bohning

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