Topic of the Month April 2012

The life and work of Hermann Staudinger

Part 2: 1920-1932

The Twenties are generally idealised as the “golden age”. Contrary to the cliché, they were in fact a decade with both ups and downs – for Hermann Staudinger too. The chemist, who had been working in Zurich since 1912, started it spectacularly: in 1920, he published his “Macromolecular Manifesto”, which gave plastics chemistry its foundations but was rejected resoundingly by the organic chemistry establishment. The opposition that Staudinger faced as a result threatened to isolate him, but he defended his theory stubbornly and continued his attempts to prove experimentally the existence of the “giant molecules” he had postulated in theory. This was a project with an uncertain outcome at first and Staudinger suffered setbacks in his private life too: his father died in 1921 and he was divorced from his wife Dora, née Förster (1886-1964), who bore him four children in the 20 years of their marriage, in 1926. 1926 marked the start of a new stage in his career as well – and one that was to prove successful: Staudinger left Zurich and returned to Germany and a position at Freiburg University. He enjoyed recognition and fame here in the Breisgau region – and finally retired from his academic career there too. It was also a happy time for Staudinger again in his private life, once he married the biologist Magda Woit (1902-1997) in 1928, who was his companion in his scientific endeavours as well up to his death in 1965.

Germany at the beginning of the 1920s: the war was over and the monarchy was a thing of the past. Hitherto unknown Republican freedom quickly helped people to forget the authoritarian state. “Anything goes” was the message spread by intellectuals; cities became the stage for experimenting with “liberté” and “libertinage”. A great deal was changing in plastics chemistry too. New empirical findings demanded a theoretical basis, but rigid, outdated thinking could not simply be abandoned as long as the explanatory concepts needed were still nebulous. A paradigm shift was in the air, but the “experimental stage” had not been passed yet:

“The term ‘plastic’ very gradually started to establish itself via a magazine of the same name that was started in 1911 by the (German, editor’s note) chemist Richard Escales (1863-1924). Nothing at all was, however, known about how these plastics were in actual fact structured and by what principles they could be synthesised in a laboratory until late in the 20s. The progress that was nevertheless evident [...] was not based on systematic research but was instead attributable to an explosive cocktail mixed together from such ingredients as experience, speculation, acquired know-how and plenty of sheer luck.” (Heimlich 1998, 79)

Basic research was vital in this uncertain situation. Hermann Staudinger did pioneering work in this field at his chair in Zurich. He was interested in “determining the composition” (Staudinger 1938, 15 and 1961, 77) of polymers, i.e. of the fascinating class of substances that included such natural substances as rubber in addition to the innovative new synthetic ones – “proper” plastics – like celluloid (1869), Galalith (1897) or Bakelite (1908). Biopolymers include, in addition, proteins, enzymes, polysaccharides (e.g. cellulose, glycogen and pectin) as well as nucleic acids, the basic components of our genetic structure, as research in subsequent decades was to show.

Fascinating class of substances with exceptional properties

The polymers produced by mankind (“synthetic”) and the polymers that are already available without mankind doing anything (“natural”) have exceptional properties and behaviour in common that no other class of substances can boast:
• In contrast to, for example, a saline solution, which cannot be distinguished visually from clear water, polymers form colloidal, i.e. glue-like, solutions, which already move between liquid and solid states at relatively low concentrations and are sometimes viscous and sometimes jelly-like (cf. Krüll 1978a, 45).
• Other properties that should be emphasised are a marked ability to swell and form fibres, high elasticity, tremendous strength and “above all the unique combination of very high stability with multiple reactivity” (Staudinger 1961, 302; cf. ibid., 95 and Staudinger 1938, 14).

It was not, however, clear at the time what gave polymers all these physical characteristics, why a polymer, as it were, has no alternative but to display such properties. Staudinger was convinced that chemists had to find the answers to these questions: “The great variety of the individual phenomena is based [...] on the fact that the ( ) atoms are joined together in very different ways.” (Staudinger 1938, 5) In order to “obtain an understanding” of the properties of the polymers, it was therefore necessary “[...] to determine the structure of their molecules; the nature of the bonds and the arrangement of the atoms in the molecule therefore need to be specified” (Staudinger 1938, 9). Understanding the specific chemical reaction that led to the creation of polymers also promised to shed light on this matter. The aim was to have this process, which was known as polymerisation, take place in a controlled fashion and to discover suitable auxiliary materials that initiated, maintained and ended the process – not least of all in order to be able to develop versatile new plastics and manufacture them on an industrial scale.