Hermann Staudinger

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German chemist Hermann Staudinger (March 23, 1881 – September 8, 1965) discovered a chemical reaction known as the Staudinger reaction. He later received the 1953 Nobel Prize in Chemistry for his characterization of polymers.

1 Staudinger’s early work: organic synthesis
2 The Staudinger reaction
3 The birth of polymer chemistry
4 A lasting legacy
5 References
6 External links

[edit] Staudinger’s early work: organic synthesis

Hermann Staudinger was born in 1881 in Worms, Germany. After receiving his Ph.D. from the University of Halle in 1903, Staudinger took a position at the University of Strasbourg.

Figure 1. The general structure of a ketene is R2C=C=O. Hydrogen atoms may take the place of the R-groups present in this diagram.

It was here that he discovered the ketene, a molecule 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 and amoxicillin.

In 1907, Staudinger began an assistant professorship at the Technical University of Karlsruhe where he successfully isolated a number of useful organic compounds (including a synthetic coffee flavoring) as more completely reviewed by Mülhaupt.^[1]

[edit] 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 azides react with triphenylphosphine to form phosphazide (Figure 2)^[2]. This reaction – commonly referred to as the Staudinger reaction – produces a high phosphazide yield.^[3]

Figure 2. Triphenylphosphine and an azide form a phosphazide and gaseous nitrogen by way of the Staudinger reaction.

[edit] The birth of polymer chemistry

While at Karlsruhe and later, Zurich, Staudinger began research in rubber chemistry. In a landmark paper^[4] published in 1920, Staudinger drew what was at the time an unusual and startling conclusion about the structure of rubber and other polymeric substances: he stated that polymers were long chains of short repeating molecular units linked by covalent bonds. In other words, polymers were like chains of paper clips; they were made up of small constituent parts linked from end to end (Figure 3).

Figure 3. A chain of paper clips (above) is a good model for a polymer such as polylactic acid (below). The polymer chain comprises small pieces linked together in a head-to-tail fashion.

This notion ran counter to the prevailing colloid theory whose proponents included prominent chemists Emil Fischer and Heinrich Wieland.^[5],^[6] 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^[7], this is due in part to the fact that molecular structure and bonding theory were not fully understood in the early 20th century. It was not until the 1930s that analytical techniques such as membrane osmometry emerged to prove Staudinger’s hypothesis.

[edit] A lasting legacy

Staudinger’s groundbreaking elucidation of the nature of the high-molecular weight compounds he termed makromoleküls^[8] 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 smartly 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.”^[9] Staudinger founded the first polymer chemistry journal in 1940^[10] and in 1953 received the Nobel Prize in Chemistry for “his discoveries in the field of macromolecular chemistry.”^[11] His pioneering research has afforded the world myriad plastics, textiles, and other polymeric materials which make consumer products more affordable, attractive, and fun.