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Hermann Staudinger (; 23 March 1881 – 8 September 1965) was a German organic chemist who demonstrated the existence of macromolecules, which he characterized as
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. For this work he received the 1953
Nobel Prize The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
in Chemistry. He is also known for his discovery of ketenes and of the
Staudinger reaction The Staudinger reaction is a chemical reaction of an organic azide with a phosphine or phosphite produces an iminophosphorane. The reaction was discovered by and named after Hermann Staudinger. The reaction follows this stoichiometry: :R3P + ...
. Staudinger, together with Leopold Ružička, also elucidated the molecular structures of pyrethrin I and II in the 1920s, enabling the development of
pyrethroid A pyrethroid is an organic compound similar to the natural pyrethrins, which are produced by the flowers of pyrethrums ('' Chrysanthemum cinerariaefolium'' and '' C. coccineum''). Pyrethroids are used as commercial and household insecticides. ...
insecticides in the 1960s and 1970s.


Early work

Staudinger was born in 1881 in Worms. Staudinger, who initially wanted to become a botanist, studied chemistry at the University of Halle, at the TH Darmstadt and at the LMU Munich. He received his "Verbandsexamen" (comparable to Master's degree) from TH Darmstadt. After receiving his Ph.D. from the University of Halle in 1903, Staudinger qualified as an academic lecturer at the University of Strasbourg in 1907. It was here that he discovered the ketenes, a family of molecules characterized by the general form depicted in Figure 1. Ketenes would prove a synthetically important intermediate for the production of yet-to-be-discovered antibiotics such as
penicillin Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from '' Penicillium'' moulds, principally '' P. chrysogenum'' and '' P. rubens''. Most penicillins in clinical use are synthesised by P. chrysogenum usin ...
and amoxicillin. In 1907, Staudinger began an assistant professorship at the Technical University of Karlsruhe. Here, he successfully isolated a number of useful organic compounds (including a synthetic coffee flavoring) as more completely reviewed by Rolf Mülhaupt. Here too he guided future Nobel laureates Leopold Ružička (1910) and Tadeusz Reichstein to their doctorates.


The Staudinger reaction

In 1912, Staudinger took on a new position at the Swiss Federal Institute of Technology in Zurich, Switzerland. One of his earliest discoveries came in 1919, when he and colleague Meyer reported that organic azides react with
triphenylphosphine Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C6H5)3 and often abbreviated to P Ph3 or Ph3P. It is widely used in the synthesis of organic and organometallic compounds. PPh3 exists ...
to form phosphinimines (Figure 2). This reaction, commonly referred to as the
Staudinger reaction The Staudinger reaction is a chemical reaction of an organic azide with a phosphine or phosphite produces an iminophosphorane. The reaction was discovered by and named after Hermann Staudinger. The reaction follows this stoichiometry: :R3P + ...
, produces a high phosphinimine yield.


Polymer chemistry

While at Karlsruhe and later, Zurich, Staudinger began research in the chemistry of
rubber Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and ...
, for which very high molecular weights had been measured by the physical methods of Raoult and
van 't Hoff Van 't Hof and Van 't Hoff are Dutch toponymic surnames meaning "from the homestead". Other variants are ''Van Hoff'', ''Van den Hof'', ''Van der Hoff'', ''Van't Hof'' and ''Vanthof''. Notable people with these surnames include: ;Van 't Hof / Van' ...
. Contrary to prevailing ideas (see below), Staudinger proposed in a landmark paper published in 1920 that
rubber Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and ...
and other
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 such as
starch Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human die ...
,
cellulose Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wa ...
and
proteins Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
are long chains of short repeating molecular units linked by covalent bonds. In other words, polymers are like chains of paper clips, made up of small constituent parts linked from end to end (Figure 3). At the time, leading organic chemists such as Emil Fischer and Heinrich Wieland believed that the measured high molecular weights were only apparent values caused by the aggregation of small molecules into colloids. At first, the majority of Staudinger’s colleagues refused to accept the possibility that small molecules could link together covalently to form high-molecular weight compounds. As Mülhaupt aptly notes, this is due in part to the fact that molecular structure and bonding theory were not fully understood in the early 20th century. In 1926, he was appointed lecturer of chemistry at the University of Freiburg at Freiburg im Breisgau (Germany), where he spent the rest of his career.Biography on Nobel prize website
/ref> In 1927, he married the Latvian botanist, Magda Voita (also shown as; german: Magda Woit), who was a collaborator with him until his death and whose contributions he acknowledged in his Nobel Prize acceptance. Further evidence to support his polymer hypothesis emerged in the 1930s. High molecular weights of polymers were confirmed by membrane osmometry, and also by Staudinger’s measurements of
viscosity The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the int ...
in solution. The X-ray diffraction studies of polymers by Herman Mark provided direct evidence for long chains of repeating molecular units. And the synthetic work led by Carothers demonstrated that polymers such as
nylon Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic. Nylon is a silk-like thermoplastic, generally made from pet ...
and
polyester Polyester is a category of polymers that contain the ester functional group in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include natura ...
could be prepared by well-understood organic reactions. His theory opened up the subject to further development, and helped place polymer science on a sound basis.


Legacy

Staudinger's groundbreaking elucidation of the nature of the high-molecular weight compounds he termed ''Makromoleküle'' paved the way for the birth of the field of polymer chemistry. Staudinger himself saw the potential for this science long before it was fully realized. "It is not improbable," Staudinger commented in 1936, "that sooner or later a way will be discovered to prepare artificial fibers from synthetic high-molecular products, because the strength and elasticity of natural fibers depend exclusively on their macro-molecular structure – i.e., on their long thread-shaped molecules." Staudinger founded the first polymer chemistry journal in 1940, and in 1953 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 ...
for "his discoveries in the field of macromolecular chemistry."The Nobel Prize in Chemistry 1953
(accessed Mar 2006).
In 1999, the
American Chemical Society The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all ...
and Gesellschaft Deutscher Chemiker designated Staudinger's work as an
International Historic Chemical Landmark The National Historic Chemical Landmarks program was launched by the American Chemical Society in 1992 to recognize significant achievements in the history of chemistry and related professions. The program celebrates the centrality of chemistry. ...
. His pioneering research has afforded the world myriad plastics, textiles, and other polymeric materials which make consumer products more affordable, attractive and enjoyable, while helping engineers develop lighter and more durable structures.


See also

* Beta-lactam *
Carbene In organic chemistry, a carbene is a molecule containing a neutral carbon atom with a valence of two and two unshared valence electrons. The general formula is or where the R represents substituents or hydrogen atoms. The term "carbene" m ...
* Hypervalent molecule * Polyoxymethylene * Pyrethrin *
Triphenylphosphine phenylimide Triphenylphosphine phenylimide is the organophosphorus compound with the formula Ph3P=NPh ( Ph = C6H5). It is a white solid that is soluble in organic solvents. The compound is a prototype of a large class of Staudinger reagents, resulting from ...
* Heidegger and Nazism: denounced or demoted non-Nazis


Notes


References

* * *


External links

* * * Staudinger's Nobel Lectur
Macromolecular Chemistry
{{DEFAULTSORT:Staudinger, Hermann 1881 births 1965 deaths ETH Zurich faculty 20th-century German chemists Organic chemists German Nobel laureates Nobel laureates in Chemistry Polymer scientists and engineers People from Worms, Germany People from Rhenish Hesse Martin Luther University of Halle-Wittenberg alumni University of Strasbourg faculty Karlsruhe Institute of Technology faculty University of Freiburg faculty Commanders Crosses of the Order of Merit of the Federal Republic of Germany Technische Universität Darmstadt alumni Swiss Nobel laureates