1. Valcanization (1839)
Goodyear uses heat and sulfur to increase the usefulness of rubber.
The idea of curing rubber goes back to prehistoric times. The Aztecs, for example, processed rubber by mixing latex with vine juice. However, vulcanization, as we now think of it, was invented by Charles Goodyear (1800-1860) in 1839 (according to his own account). Although Goodyear patented his invention in 1844, he died with huge debts in 1860.
Named after Valcan, the Roman god of fire, valcanization is a process of curing rubber using high temperatures and the addition of sulfur. In its nature state, rubber is sticky, deforms when warm, and is brittle when cold. But by linking together the polymer molecules in rubber with bridges of sulfur atoms, it become much harder, less sticky, more resistant, and much more durable. As a result, valcanized rubber has a whole rang of useful applications, not least in sealing gaps between moving parts, thereby playing a crucial part in the development of more efficient industrial machines. The ability of vulcanized rubber to absorb stress then revert to its originl shape has made it an idea material for products such as tires, shoes, and rubber bands, while its water- resistant qualities make it perfect for boots, wet weather clothes, and waterproof linings and coatings.
While valcanization revolutionized manufacturing processes in the nineteenth and twentieth centuries, environment concerns now focus on how to recycle valcanized rubber. Some one billion rubber tires, for example, are produced annunally but only about 10 per cent of waste rubber is reused. Efforts are now being made to find ways to devucanize rubber without losing all those important properties.
This Woodcut Form 1867 Shows The Process Of Valcanization At A German Rubber Factory.
2. Artificial Fertilizer (c. 1839)
Von Liebig makes a scientific approach to maintaining soil fertility.
Until Justus von Liebig (1803-1873) investigated continuance of soil fertility, agricultural fertilizer came in the form of animal dung, cinder, or ironmaking slag. Von Liebig, a chemist by training, rejected the hypothesis that plants gained all their nutrition from partially or completely decayed animal and vegetable matter in the soil, suggesting instead that plants gained carbon and nitrogen from carbon dioxide and ammonia in the atmoshere. These gases would be in plentiful supply since the process of decay would return the gases to the atmosphere, so the only nutrients supplied by the soil were minerals. Since these would be the limiting factor in the growth of crops, all a farmer had to do was determine which mineral each plant needed, by analysis of its ashes, and provide the soil with the requisite chemical compounds.
Von Liebig's initial experiments in this area were a failure as he had taken pains to add alkaline compounds in an insoluble form, which- while avoiding their being washed away by rain- also precluded their being taken up by plant roots.
Von Liebig's work led directly to the development of artifical fertilizers and their widespread use in farming. Unfortunately the overuse of chemical fertilizers is now through to have a widespread environmental impact, being held responsible for the accumulation of heavy metals in soil. The leaching of nitrates into waterways leads to the process of eutrophication, causing a sudden growth of algae that removes oxygen from the water, killing fish and plants.
Currently efforts are being made to reduce fertilizer use worldwide by applying it more efficiently.
Drawing Of The First Practical Teaching Laboratory Used By Von Liebig At The University Of Giessen, Germany.
Goodyear uses heat and sulfur to increase the usefulness of rubber.
The idea of curing rubber goes back to prehistoric times. The Aztecs, for example, processed rubber by mixing latex with vine juice. However, vulcanization, as we now think of it, was invented by Charles Goodyear (1800-1860) in 1839 (according to his own account). Although Goodyear patented his invention in 1844, he died with huge debts in 1860.
Named after Valcan, the Roman god of fire, valcanization is a process of curing rubber using high temperatures and the addition of sulfur. In its nature state, rubber is sticky, deforms when warm, and is brittle when cold. But by linking together the polymer molecules in rubber with bridges of sulfur atoms, it become much harder, less sticky, more resistant, and much more durable. As a result, valcanized rubber has a whole rang of useful applications, not least in sealing gaps between moving parts, thereby playing a crucial part in the development of more efficient industrial machines. The ability of vulcanized rubber to absorb stress then revert to its originl shape has made it an idea material for products such as tires, shoes, and rubber bands, while its water- resistant qualities make it perfect for boots, wet weather clothes, and waterproof linings and coatings.
While valcanization revolutionized manufacturing processes in the nineteenth and twentieth centuries, environment concerns now focus on how to recycle valcanized rubber. Some one billion rubber tires, for example, are produced annunally but only about 10 per cent of waste rubber is reused. Efforts are now being made to find ways to devucanize rubber without losing all those important properties.
This Woodcut Form 1867 Shows The Process Of Valcanization At A German Rubber Factory.
2. Artificial Fertilizer (c. 1839)
Von Liebig makes a scientific approach to maintaining soil fertility.
Until Justus von Liebig (1803-1873) investigated continuance of soil fertility, agricultural fertilizer came in the form of animal dung, cinder, or ironmaking slag. Von Liebig, a chemist by training, rejected the hypothesis that plants gained all their nutrition from partially or completely decayed animal and vegetable matter in the soil, suggesting instead that plants gained carbon and nitrogen from carbon dioxide and ammonia in the atmoshere. These gases would be in plentiful supply since the process of decay would return the gases to the atmosphere, so the only nutrients supplied by the soil were minerals. Since these would be the limiting factor in the growth of crops, all a farmer had to do was determine which mineral each plant needed, by analysis of its ashes, and provide the soil with the requisite chemical compounds.
Von Liebig's initial experiments in this area were a failure as he had taken pains to add alkaline compounds in an insoluble form, which- while avoiding their being washed away by rain- also precluded their being taken up by plant roots.
Von Liebig's work led directly to the development of artifical fertilizers and their widespread use in farming. Unfortunately the overuse of chemical fertilizers is now through to have a widespread environmental impact, being held responsible for the accumulation of heavy metals in soil. The leaching of nitrates into waterways leads to the process of eutrophication, causing a sudden growth of algae that removes oxygen from the water, killing fish and plants.
Currently efforts are being made to reduce fertilizer use worldwide by applying it more efficiently.
Drawing Of The First Practical Teaching Laboratory Used By Von Liebig At The University Of Giessen, Germany.
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