Inside the Collection

What is plastic? a chemical controversy

Bust made of orange plastic
Collection: Powerhouse Museum

Bakelite is rightly famous as the first fully synthetic plastic (defined as an organic material that can be moulded under heat and/or pressure). Its name immortalises its inventor, Leo Baekeland. The Museum’s bust of this balding moustachioed chemist and industrialist, made from a translucent red version of his phenol-formaldehyde resin, also celebrates his place in technological history.

Unfortunately, we have no bust of Hermann Staudinger, the balding moustachioed Nobel-Prize-winning chemist whose work underpins the scientific understanding of plastics. His story is one of heroic struggle against orthodox thinking and the eventual acceptance of his revolutionary idea: that plastic materials consist of long chain molecules called macromolecules.

Staudinger first formulated this theory in 1920, in opposition to the theory that plastics consist of aggregates of small molecules. Organic chemistry had thrown much light on naturally occurring substances, and it had done this by extracting and studying a wealth of small molecules of fixed, reproducible composition. Staudinger’s huge macromolecules, made up of variable length chains of atoms, did not fit neatly into this picture.

Plastic horn comb
Collection: Powerhouse Museum

Humans have used natural plastics for thousands of years, moulding and carving them to make useful and decorative objects. This back-comb made from horn in Scotland in the late 1800s is an elaborate example. It is stained to look like tortoiseshell, a more prized material than horn.

A collection of 1933 plastic casein objects
Collection: Powerhouse Museum. Gift of Messrs Galalith Hoff & Co, 1933

These casein products were made in 1933. Made from milk protein and formaldehyde and easily pigmented, casein was patented in Germany in 1899. It was one of several semi-synthetic plastics that initiated the plastics age in the nineteenth century: Parkesine, xylonite and celluloid were all derived from cellulose; and vulcanite and ebonite were made from rubber.

Plastic cell acetate glasses
Collection: Powerhouse Museum. Gift of Commonwealth Moulding Co, 1945

Cellulose acetate was another early plastic. This spectacle frame is a typical product made from cellulose acetate, which can also be extruded to make fibres. Huge quantities of cellulose are used to make rayon; if you wear clothing made from this semi-synthetic fibre, remember that it started life as a tree!

Plastic Razor Scuttlebug
Razor Scuttlebug. Collection: Powerhouse Museum. Gift of Funtastic Ltd, 2006

When you contemplate the range and usefulness of plastic objects today, I hope you remember Staudinger’s story. He studied rubber, cellulose and synthetic polymers, devising ways to measure the mass of their molecules and designing experiments to discover their chemical reactions. His wife and co-worker, Magda Staudinger, applied a range of microscopy techniques to studying macromolecules. All the evidence his team accumulated eventually convinced other chemists, and he was awarded the Nobel Prize for Chemistry in 1953, a third of a century after he proposed his revolutionary idea.

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