When was polymer discovered

British and French chemists in the 19th century showed that natural rubber was a polymer of isoprene C 5 H 8 , and a synthetic version of it was produced in Germany in During the first world war, several combatants used rubber substitutes, and research continued afterwards, driven by fears that natural sources would not meet the increasing demand.

Staudinger played little part in the industrial dimension of this activity, and patented very few of his discoveries. His chief concern was the chemical composition of these problematic polymers. Leading European chemists, like the German Carl Harries and the Swiss Paul Karrer, had long argued that natural materials such as rubber, cellulose, and proteins consisted of aggregates of relatively small molecules, loosely linked by intermolecular forces weaker than normal valence bonds.

They thought individual molecules with relative masses greater than about units must be unstable, and would disintegrate spontaneously if synthesised. Staudinger, however, argued that polymers linked only by normal chemical bonds could have molecular masses measured in millions. Resolving this dispute was difficult, because with standard laboratory solvents these substances — even when pure — generally formed colloidal suspensions rather than solutions.

In Staudinger lacked conclusive evidence for his thesis — getting it would require much effort and ingenuity. In , Staudinger and his assistants tested this hypothesis by hydrogenating rubber to open up its double bonds. Apparently, hydrogenation had not broken up the hypothetical aggregates. But his critics remained unconvinced, and Staudinger was challenged vigorously on his return to Germany in His new appointment at the University of Freiburg was doubly controversial.

For many, his wartime pacifism remained as objectionable as his ideas on macromolecules. Staudinger must have expected some hostility when he accepted the Freiburg chair. But he could scarcely have foreseen that the Nazi coup in would put his career, his liberty — and possibly his life — at risk.

Dorothea remained in Zurich with their children, and subsequently married a communist. In , Herman married Magda Voita, a Latvian biologist whose research on plant physiology and particularly on cell wall membranes closely paralleled his own. Magda became his life-long collaborator, and oversaw the posthumous publication of his complete works.

To convince his critics, Staudinger sought more data about the colloidal suspensions which so many natural products formed with standard solvents. A fresh approach to them had recently emerged from studies of Brownian motion — the random buffeting of barely detectable colloidal particles by invisible solvent molecules. Calculations by Albert Einstein then a Swiss citizen and Polish physicist Marian Smoluchowski, when applied to observations by the French physicist Jean Perrin, now made it possible to estimate the mass of these particles.

Nevertheless, Staudinger could not yet prove that colloid particles were individual macromolecules, rather than the aggregates posited by his opponents. There were similar objections to estimates of the molecular masses of colloids calculated from osmotic pressure measurements. By varying the reaction conditions for a given monomer, they generated a range of products which could be ordered like a homologous series. Starting with simpler substances of known composition and upscaling to more complex ones, they established a relationship between viscosity and molecular mass, now known as the Staudinger law.

The x-ray crystallographer Herman Mark was more sympathetic to the macromolecular idea, but remained unconvinced until later x-ray observations began supporting it. Meanwhile, fresh data was generated by the ultracentrifuge , an instrument developed by Swedish physical chemist Theodor Svedberg when he was a visiting professor at the University of Wisconsin in the US in This enabled him to isolate pure substances, and — by comparing rates of sedimentation — to estimate their molecular masses.

In Svedberg found the relative mass of the haemoglobin molecule to be approximately 68, units, and in he put the molecular mass of haemocyanin the blood pigment of the snail helix pomatia at about 5 million. Naturally, Staudinger was keen to acquire his own ultracentrifuge, but he could not raise the necessary funds. Meanwhile, chemical research in the US was being generously supported by industry. The creation of new materials also helped free people from the social and economic constraints imposed by the scarcity of natural resources.

Inexpensive celluloid made material wealth more widespread and obtainable. And the plastics revolution was only getting started. In Leo Baekeland invented Bakelite, the first fully synthetic plastic, meaning it contained no molecules found in nature. Baekeland had been searching for a synthetic substitute for shellac, a natural electrical insulator, to meet the needs of the rapidly electrifying United States.

Bakelite was not only a good insulator; it was also durable, heat resistant, and, unlike celluloid, ideally suited for mechanical mass production. While Hyatt and Baekeland had been searching for materials with specific properties, the new research programs sought new plastics for their own sake and worried about finding uses for them later.

World War II necessitated a great expansion of the plastics industry in the United States, as industrial might proved as important to victory as military success.

The need to preserve scarce natural resources made the production of synthetic alternatives a priority. Plastics provided those substitutes. Nylon, invented by Wallace Carothers in as a synthetic silk, was used during the war for parachutes, ropes, body armor, helmet liners, and more. Plexiglas provided an alternative to glass for aircraft windows.

The surge in plastic production continued after the war ended. After experiencing the Great Depression and then World War II, Americans were ready to spend again, and much of what they bought was made of plastic. In the postwar years there was a shift in American perceptions as plastics were no longer seen as unambiguously positive. Plastic debris in the oceans was first observed in the s, a decade in which Americans became increasingly aware of environmental problems.

In a major oil spill occurred off the California coast and the polluted Cuyahoga River in Ohio caught fire, raising concerns about pollution. As awareness about environmental issues spread, the persistence of plastic waste began to trouble observers.

Plastic also gradually became a word used to describe that which was cheap, flimsy, or fake. Audiences cringed along with Hoffman at what they saw as misplaced enthusiasm for an industry that, rather than being full of possibilities, was a symbol of cheap conformity and superficiality. Plastic became a special target because, while so many plastic products are disposable, plastic lasts forever in the environment.

In particular, recent measurement techniques were introduced to evaluate the limited number of new polymers with high T g and T m. Thermal diffusivity was measured by micro-scale TWA 38 see Fig. Ultra-fast scanning nano-scale calorimetry FSC, 40 see Fig. The digital data in PoLyInfo were manually extracted because acquisition using an application programming interface is not currently supported.

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