HOME

TheInfoList



OR:

Paul John Flory (June 19, 1910 – September 9, 1985) was an American chemist and
Nobel laureate The Nobel Prizes ( sv, Nobelpriset, no, Nobelprisen) are awarded annually by the Royal Swedish Academy of Sciences, the Swedish Academy, the Karolinska Institutet, and the Norwegian Nobel Committee to individuals and organizations who make o ...
who was known for his work in the field of
polymers A polymer (; Greek '' poly-'', "many" + '' -mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic a ...
, or
macromolecules A macromolecule is a very large molecule important to biophysical processes, such as a protein or nucleic acid. It is composed of thousands of covalently bonded atoms. Many macromolecules are polymers of smaller molecules called monomers. The ...
. He was a leading pioneer in understanding the behavior of
polymer A polymer (; Greek '' poly-'', "many" + '' -mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic a ...
s in solution, and won the
Nobel Prize in Chemistry ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "M ...
in 1974 "for his fundamental achievements, both theoretical and experimental, in the physical chemistry of macromolecules".


Biography


Personal life

Flory was born in Sterling, Illinois, on June 19, 1910. He was raised by Ezra Flory and Nee Martha Brumbaugh. His father worked as a clergyman-educator, and his mother was a school teacher. He first gained his interest in science from Carl W Holl, who was a professor in chemistry. Holl was employed in Indiana at Manchester College as a chemistry professor. In 1936, he married Emily Catherine Tabor. He and Emily had three children together; Susan Springer, Melinda Groom and Paul John Flory jr. They also had five grandchildren. All of his children pursued careers in the field of science. After graduating from Elgin High School in
Elgin, Illinois Elgin ( ) is a city in Cook and Kane counties in the northern part of the U.S. state of Illinois. Elgin is located northwest of Chicago, along the Fox River. As of the 2020 Census, the city had a population of 114,797, the seventh-larg ...
in 1927, Flory received a bachelor's degree from
Manchester College (Indiana) Manchester University (formerly Manchester College) is a private liberal arts university associated with the Church of the Brethren and two locations, a residential campus in North Manchester, Indiana, and a second location in Fort Wayne, Indiana ...
(now Manchester University) in 1931 and a Ph.D. from the
Ohio State University The Ohio State University, commonly called Ohio State or OSU, is a public land-grant research university in Columbus, Ohio. A member of the University System of Ohio, it has been ranked by major institutional rankings among the best pub ...
in 1934. His first position was at
DuPont DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in ...
with
Wallace Carothers Wallace Hume Carothers (; April 27, 1896 – April 29, 1937) was an American chemist, inventor and the leader of organic chemistry at DuPont, who was credited with the invention of nylon. Carothers was a group leader at the DuPont Experimen ...
. He was posthumously inducted into the
Alpha Chi Sigma Alpha Chi Sigma () is a professional fraternity specializing in the fields of the chemical sciences. It has both collegiate and professional chapters throughout the United States consisting of both men and women and numbering more than 70,000 me ...
Hall of Fame in 2002. Flory died on September 9, 1985 due to a massive heart attack. His wife Emily died in 2006 aged 94.


Schooling

Flory attended graduate school at the Ohio State University. He originally entered the University under the major of just physical science. The research for his work included the studies of
photochemistry Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet ( wavelength from 100 to 400  nm), visible light (400� ...
and spectroscopy. He completed his Ph.D. at Ohio State University in 1934. Durings his studies at Ohio State University, he discovered the understanding that as temperature decreases, the polymer ends up contracting. This leads to the establishment of forces balancing one another's temperature. He ended up with receiving a master's degree in organic chemistry. He received his masters in organic chemistry, rather than physics due to insecurity. After facing his fear, he was able to graduate in 1934 with his doctorate in physical chemistry. While receiving his doctorate, he was supervised by Herriacc Johnston with his thesis on photochemistry of nitric oxide. In 1934, after receiving his Ph.D, he joined the Central Department of Dupont and Company. Throughout this organization he gained an interest in the fundamentals of polymerization and polymeric systems. Flory discovered that polymers that are valid objects of scientific were proved contagious. He proved the hypothesis by Staudinger and Carothers, “polymers are in fact covalently linked macromolecules”. After the death of Carother in 1937, Flory was involved for two years at the Research Laboratory located in the University of Cincinnati.


Work

During the time of World War II, there was a need for research having to do with the development of synthetic rubber. Flory became reinvolved with the industry work. The first industry we worked from 1940 to 1943 was Standard Oil Development Company. Which is located in Linden, NJ. Working here helped with his development of mechanical statistical theory of polymer mixtures. During 1943 to 1948 was the Research Laboratory of the Goodyear Tire and Rubber Company. In fact, he was the director of research at the Goodyear Tire and Rubber Company, leading the team for studies on polymers. After working in the industry, Flory left to work at Cornell University for a lectureship. The lectureship was with the George Fisher Baker Non-Residents. During the lectureship, Flory was able to study and understand a way to treat the effect of the excluded volume. According the nobelprize.org polymers, “would be nonasymptotic with the length of the chain, that is the fear of the contribution by the exclusion of the segment of the chain from the space occupied would increase without a limit as the chain is lengthened. This was the volume on the configuration of polymer chains. In 1957, Flory and his family decided to make the move to Pittsburgh, Pennsylvania. The reason he and his family moved from New York to Pennsylvania was for him to be able to develop a program of basic research in chemistry at the Carnegie Mellon Institute. After his work at the Carnegie Mellon Institute, he accepted a professorship position at Stanford University in the department of chemistry. While he was at Stanford University, he changed his direction of research. The change of view in his studies has to do with the spatial configuration having to do with chain molecules. This have to do with configuration treatments having to do with chain molecules. The treatment is the dependent properties through mathematical methods. Not only is mathematical methods the only treatment but so is the thermodynamics of solutions. After his retirement he Flory remained still very active in the world of chemistry. He was a consultant for Dupont and IBM, not long after he retired. Flory also was involved with the study of the foundations in the Soviet Union started off by the professor MV Volkenstein and his collaborators. He also worked with the late professor of Kazuo Nagai in Japan. He felt the need to fight for scientists who were oppressed in various countries. In addition, he also spoke as the “Voice of America”, during a broadcast in Eastern Europe as well as Soviet Union. Flory also worked for the “Committee on Human Rights” which is known as the National Academy of Sciences from 1979 to 1984. During 1980, he worked as a delegate at the scientific forum in Hamburg.


Research

After receiving his doctorate in 1934, he dealt with a variety of issues with physical chemistry. This having to do with the kinetics and mechanisms of polymeric substances. Having to do with the distribution of molar mass, solution of thermodynamics and hydrodynamics. In addition, during 1934, he also was able to discover that when polymeric chains will keep growing if they are mixed with other molecules when present. Flory also discovered the understanding of the term ‘theta.’ In other words, is the constant of hydrodynamic. With the theta point that is the neutral volumes interactions. In conclusion to the development of the theta point it has been confirmed and studied in a variety of laboratories by many scientists. Both natural and synthetic polymers have been studied throughout the theta point. Throughout this a better understanding of macromolecules was provided. It helped with the creation of basis under rational interpretations of physical measurements. The measurements have relations to both the solutions of polymers and quantitative characteristics. Some work completed by Paul Flory during his time includes the development in the quantitative correlations between the chain molecules and chemical structure of properties. This has to do with the way polymers are composed and what are composed of polymers. One piece of material formed through polymers is plastic. In the mid 1930s, Flory discovered how polymers are dissolved in a solvent. Leading to becoming outstretches which is caused by the forces of both polymers and solvent parts. He even had part finding a solution to polymers.


Career and polymer science

Flory's earliest work in polymer science was in the area of
polymerization In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many f ...
kinetics Kinetics ( grc, κίνησις, , kinesis, ''movement'' or ''to move'') may refer to: Science and medicine * Kinetics (physics), the study of motion and its causes ** Rigid body kinetics, the study of the motion of rigid bodies * Chemical kin ...
at the DuPont Experimental Station. In
condensation polymerization In polymer chemistry, condensation polymers are any kind of polymers whose process of polymerization involves a condensation reaction (i.e. a small molecule, such as water or methanol, is produced as a byproduct). Condensation polymers are ...
, he challenged the assumption that the reactivity of the end group decreased as the macromolecule grew, and by arguing that the reactivity was independent of the size, he was able to derive the result that the number of chains present decreased with size exponentially. In
addition polymerization Chain-growth polymerization ( AE) or chain-growth polymerisation ( BE) is a polymerization technique where unsaturated monomer molecules add onto the active site on a growing polymer chain one at a time. There are a limited number of these acti ...
, he introduced the important concept of
chain transfer Chain transfer is a polymerization reaction by which the activity of a growing polymer chain is transferred to another molecule. :P• + XR' → PX + R'• Chain transfer reactions reduce the average molecular weight of the final polymer. Ch ...
to improve the kinetic equations and remove difficulties in understanding the polymer size distribution. In 1938, after Carothers' death, Flory moved to the Basic Science Research Laboratory at the
University of Cincinnati The University of Cincinnati (UC or Cincinnati) is a public research university in Cincinnati, Ohio. Founded in 1819 as Cincinnati College, it is the oldest institution of higher education in Cincinnati and has an annual enrollment of over 44,0 ...
. There he developed a mathematical theory for the polymerization of compounds with more than two functional groups and the theory of polymer networks or
gels A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state, although the liquid phase may still dif ...
. This led to the Flory-Stockmayer theory of gelation, which equivalent to
percolation Percolation (from Latin ''percolare'', "to filter" or "trickle through"), in physics, chemistry and materials science, refers to the movement and filtering of fluids through porous materials. It is described by Darcy's law. Broader applicatio ...
on the
Bethe lattice In statistical mechanics and mathematics, the Bethe lattice (also called a regular tree) is an infinite connected cycle-free graph where all vertices have the same number of neighbors. The Bethe lattice was introduced into the physics literature ...
and in fact represents the first paper in the percolation field. In 1940 he joined the Linden, NJ laboratory of the
Standard Oil Standard Oil Company, Inc., was an American oil production, transportation, refining, and marketing company that operated from 1870 to 1911. At its height, Standard Oil was the largest petroleum company in the world, and its success made its co- ...
Development Company where he developed a statistical mechanical theory for polymer mixtures. In 1943 he left to join the research laboratories of Goodyear as head of a group on polymer fundamentals. In the Spring of 1948
Peter Debye Peter Joseph William Debye (; ; March 24, 1884 – November 2, 1966) was a Dutch-American physicist and physical chemist, and Nobel laureate in Chemistry. Biography Early life Born Petrus Josephus Wilhelmus Debije in Maastricht, Netherland ...
, then chairman of the chemistry department at
Cornell University Cornell University is a private statutory land-grant research university based in Ithaca, New York. It is a member of the Ivy League. Founded in 1865 by Ezra Cornell and Andrew Dickson White, Cornell was founded with the intention to tea ...
, invited Flory to give the annual Baker Lectures. He then was offered a position with the faculty in the Fall of the same year. He was initiated into the Tau chapter of
Alpha Chi Sigma Alpha Chi Sigma () is a professional fraternity specializing in the fields of the chemical sciences. It has both collegiate and professional chapters throughout the United States consisting of both men and women and numbering more than 70,000 me ...
at Cornell in 1949.Fraternity – Awards – Hall of Fame
Alpha Chi Sigma (May 23, 2018). Retrieved on 2018-07-17.
At Cornell he elaborated and refined his Baker Lectures into his magnum opus, ''Principles of Polymer Chemistry'' which was published in 1953 by
Cornell University Press The Cornell University Press is the university press of Cornell University; currently housed in Sage House, the former residence of Henry William Sage. It was first established in 1869, making it the first university publishing enterprise in ...
. This quickly became a standard text for all workers in the field of polymers, and is still widely used to this day. Flory introduced the concept of
excluded volume The concept of excluded volume was introduced by Werner Kuhn in 1934 and applied to polymer molecules shortly thereafter by Paul Flory. Excluded volume gives rise to depletion forces. In liquid state theory In liquid state theory, the 'excluded ...
, coined by Werner Kuhn in 1934, to polymers. Excluded volume refers to the idea that one part of a long chain molecule can not occupy space that is already occupied by another part of the same molecule. Excluded volume causes the ends of a polymer chain in a solution to be further apart (on average) than they would be were there no excluded volume. The recognition that excluded volume was an important factor in analyzing long-chain molecules in solutions provided an important conceptual breakthrough, and led to the explanation of several puzzling experimental results of the day. It also led to the concept of the theta point, the set of conditions at which an experiment can be conducted that causes the excluded volume effect to be neutralized. At the theta point, the chain reverts to ideal chain characteristics – the long-range interactions arising from excluded volume are eliminated, allowing the experimenter to more easily measure short-range features such as structural geometry, bond rotation potentials, and steric interactions between near-neighboring groups. Flory correctly identified that the chain dimension in polymer melts would have the size computed for a chain in ideal solution if excluded volume interactions were neutralized by experimenting at the theta point. Among his accomplishments are an original method for computing the probable size of a polymer in good solution, the Flory-Huggins Solution Theory, and the derivation of the Flory exponent, which helps characterize the movement of polymers in solution.


The Flory convention

:''see Flory convention for details.'' In modeling the position vectors of atoms in macromolecules it is often necessary to convert from
Cartesian coordinates A Cartesian coordinate system (, ) in a plane is a coordinate system that specifies each point uniquely by a pair of numerical coordinates, which are the signed distances to the point from two fixed perpendicular oriented lines, measured in ...
(x,y,z) to
generalized coordinates In analytical mechanics, generalized coordinates are a set of parameters used to represent the state of a system in a configuration space. These parameters must uniquely define the configuration of the system relative to a reference state.,p. 39 ...
. The Flory convention for defining the variables involved is usually employed. For an example, a peptide bond can be described by the x,y,z positions of every atom in this bond or the Flory convention can be used. Here one must know the
bond length In molecular geometry, bond length or bond distance is defined as the average distance between nuclei of two bonded atoms in a molecule. It is a transferable property of a bond between atoms of fixed types, relatively independent of the rest of ...
s l_i,
bond angle Bond or bonds may refer to: Common meanings * Bond (finance), a type of debt security * Bail bond, a commercial third-party guarantor of surety bonds in the United States * Chemical bond, the attraction of atoms, ions or molecules to form chemical ...
s \theta_i, and the
dihedral angle A dihedral angle is the angle between two intersecting planes or half-planes. In chemistry, it is the clockwise angle between half-planes through two sets of three atoms, having two atoms in common. In solid geometry, it is defined as the un ...
s \phi_i. Applying a vector conversion from the Cartesian coordinates to the generalized coordinates will describe the same three-dimensional structure using the Flory convention.


Awards and Honors

Flory was elected to the United States
National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nat ...
in 1953 and the
American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, a ...
in 1957. In 1968, he received the
Charles Goodyear Medal The Charles Goodyear Medal is the highest honor conferred by the American Chemical Society, Rubber Division. Established in 1941, the award is named after Charles Goodyear, the discoverer of vulcanization, and consists of a gold medal, a framed ...
. He also received the
Priestley Medal The Priestley Medal is the highest honor conferred by the American Chemical Society (ACS) and is awarded for distinguished service in the field of chemistry. Established in 1922, the award is named after Joseph Priestley, the discoverer of oxygen ...
and the Golden Plate Award of the
American Academy of Achievement The American Academy of Achievement, colloquially known as the Academy of Achievement, is a non-profit educational organization that recognizes some of the highest achieving individuals in diverse fields and gives them the opportunity to meet ...
in 1974. He received the Carl-Dietrich-Harries-Medal for commendable scientific achievements in 1977. Flory received the
Nobel Prize in Chemistry ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "M ...
in 1974 "for his fundamental achievements both theoretical and experimental, in the physical chemistry of the macromolecules." Additionally in 1974 Flory was awarded the
National Medal of Science The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social scienc ...
in Physical Sciences. The medal was presented to him by President
Gerald Ford Gerald Rudolph Ford Jr. ( ; born Leslie Lynch King Jr.; July 14, 1913December 26, 2006) was an American politician who served as the 38th president of the United States from 1974 to 1977. He was the only president never to have been elected ...
. This award was given to him because of his research on the "formation and structure of polymeric substances".


Published books

With over 300 writings, both published and unpublished, throughout his lectureship at the University with the research and teaching led to his first published book. The book published by Cornell University was called the “Principles of Polymer Chemistry.” The book was then the basis use of information for undergrad students. It was the standard principle for many decades, used by many professors. Another book which was published by Flory was “Statistical Mechanics of Chain Molecules.” The book was published in 1969, worked to summarize different parts both molecules theories and applications. In 1985, the book written by Paul Flory called, “Selected Works of Paul Flory.” This summarized much of his work and studies.


Bibliography

*Flory, Paul. (1953) ''Principles of Polymer Chemistry''. Cornell University Press. . *Flory, Paul. (1969) ''Statistical Mechanics of Chain Molecules''. Interscience. . Reissued 1989. . *Flory, Paul. (1985) ''Selected Works of Paul J. Flory''. Stanford Univ Press. .


References

*Paul J. Flory – Facts. NobelPrize.org. Nobel Media AB 2019. Wed. 19 Jun 2019. *Somsen, Geert. Paul J Flory. Encyclopædia Britannica. June 15, 2019. https://www.britannica.com/biography/Paul-J-Flory *Paul John Flory. Stanford Chemistry. https://chemistry.stanford.edu/people/flory.


External links

* Chemistry Tree
Paul J. Flory Details
* A short autobiography of Paul Flory
Nobel lecture by Paul Flory
*
Paul J. Flory papers
at th
Hoover Institution ArchivesNational Academy of Sciences Biographical Memoir
{{DEFAULTSORT:Flory, Paul John 1910 births 1985 deaths People from Elgin, Illinois People from Sterling, Illinois American Nobel laureates Nobel laureates in Chemistry Ohio State University alumni American physical chemists National Medal of Science laureates Polymer scientists and engineers Fellows of the American Physical Society Members of the American Philosophical Society