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Retrospect

The plastic age

A hundred years ago, the first synthetic resin was invented

DAN PALATNIK / WWW.PALAT.COM.BRModel of radio in bakelite used after 1930DAN PALATNIK / WWW.PALAT.COM.BR

When they asked inventor and businessman Leo Hendriz Baekeland why he entered the field of synthetic resins, he replied without hesitating: “to make money.”

A Belgian who had settled in the United States at the end of the 19th century, Baekeland (1863-1944) was not only a brilliant chemist, but also an entrepreneur of vision. Before creating bakelite, the first synthetic plastic, in 1893 he invented Velox, a photographic printing paper sensitive to artificial light , and sold it six years later to George Eastman, the creator of Kodak, for almost US$ 1 million – an astronomical sum for the time.

Rich at the age of 36, the chemist began to look for another challenge. He found it in the midst of a serious problem for the growing electricity industry: where to get abundant, low-cost insulators? For centuries, the solution had been shellac, a product made from a natural resin produced by lac insects, a parasite (Laccifer lacca) that inhabits trees in Asia. But with the rapid industrialization of electricity, the demand for shellac exploded.

Baekeland decided to enter the race to find a synthetic replacement. For three years, he read everything about phenols and formaldehydes – abundant and cheap synthetic substances – and repeated experiments already done. He knew that the key lay in interrupting, at the right moment, polymerization (a process in which small molecules are aggregated to form macromolecules, which are longer).

He used all the known solvents, but he did not arrive at a synthetic product similar to shellac. When he noticed that phenol and formaldehyde together resulted in a hard substance, Baekeland gave a new direction to the research: why not make a resin that could be melted and modeled? Instead of retarding polymerization, he speeded it up with the use of heat and pressure. He used an autoclave machine and achieved an amber-colored paste that could be transformed into any object. The era of plastic began there.

The chemist arrived at this result in 1907 and formally presented it to the American Chemical Society two years afterwards. For being heat-resistant, and able to be laminated and molded in the initial stage of production and having a low cost, bakelite had many applications, besides being used as an insulator by the electrical industry. It was known as the “material of a thousand uses”: from radios to costume jewelry, from toys to telephones, from billiard balls to cameras. As it could not be remelted, it was even used as currency in Indonesia during the Second World War.

“With the development of new, less rigid, more resistant and lighter plastics, bakelite lost ground in all the markets as from the 1960’s” says Roberto Mendonça Farias, a researcher from the Physics Institute of the University of São Paulo in São Carlos and from the Multidisciplinary Polymeric Materials Institute. As to Baekeland, he attained his objectives. He founded the General Bakelite Corp and became even richer.

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