The process of 'vulcanization', that converts natural rubber into a long-lasting material, was invented by Charles Goodyear in the year 1839.
Rubber is one of the most commonly and extensively used commodity in today's world. It is used in the manufacturing of tires, toys, belts, and gaskets, along with many other things. There are two varieties of rubber available to choose from - natural and man-made. Natural rubber is obtained from the exudation of plants, while the man-made variant, known as synthetic rubber, is synthesized from petroleum byproducts.
Since the invention of vulcanization, rubber has been used on a large scale in industries. The demand further increased with an increase in the manufacturing of automobiles. Thus, it was only natural for people to start looking into its composition. For this purpose, rubber was heated in order to break it down, and scientists found that it contained isoprene. Methyl isoprene, a type of synthetic rubber, was synthesized for the first time in the year 1909, by a team that was led by Fritz Hofmann working at Bayer laboratory in Elberfeld, Germany.
Both the World Wars had played a vital role for different nations to look for options beyond natural rubber. During the First World War, there was a drop in the availability of natural rubber from the countries in South America, mainly Brazil. During the war, rubber became an essential commodity, as it was of use in each and every place and thing imaginable, like battlefields, residences, and various industries.
Yet, the need to give an emphasis on the production of synthetic rubber was not as pronounced as it was during the Second World War. The plantations in Southeast Asia were under the control of the Japanese, which gave the Axis powers control over almost all the market of natural rubber. This prompted the United States to take major steps to drastically improve its production of synthetic rubber in a short span of time. Along with this, they also had subjected the rubber manufacturing plants of Germany to cripple their manufacturing of Buna rubber, that was made from butadiene (Bu) and Sodium (Na).
The production of synthetic rubber received a major boost during WWII; however, the demand for synthetic rubber continued to remain high even after the war had come to an end. Since then, there have been attempts to reduce the dependency on natural rubber. In the latter half of the 20th century, with improvement in quality, the demand for synthesized rubber had grown over its natural variant. Today, close to two-thirds of the total rubber that is used around the world is synthetic.
Various types of rubbers have been synthesized since the invention of synthetic rubber. Given below are some of the common types of synthetic rubbers that are used in different industries.
- Polychloroprene (CR): It is also commonly known as 'neoprene' and shows a greater resistance to heat along with better chemical stability. Owing to these properties, it is used in laptop sleeves, gaskets, fan belts of automobiles, and hoses.
- Styrene-Butadiene (SBR): This rubber shows better resistance to abrasion as well as wear and tear, and is hence used in tires, mainly of buses and aircraft. It is also used in conveyor belts and the soles of shoes.
- Ethylene Propylene Diene Monomer (EPDM): Along with heat and weather, this rubber shows good resistance to various chemicals. It is used in the heat collectors present in solar panels, mechanical vibrators, electrical insulation, and radiators.
- Acrylonitrile Butadiene (NBR): It shows better resistance to chemicals. This makes it useful in the production of lab gloves and oil seals. It is also used in synthetic leather, V belts, and O rings.
- Polysiloxane (SI): It provides electrical insulation, and has low chemical and thermal conductivity. Also known as silicone rubber, it is used in coatings, as a sealant, and to make molds like the ones used in dentistry.
- Chloro Isobutylene Isoprene (CIIR): It has good physical properties, and shows resistance to heat and weathering. It is used as a additive in oils and fuels. It is also used in the manufacturing of various sports goods, and chewing gum as well.
- Chlorosulphonated Polyethylene (CSM): Along with resistance to chemicals and temperature, this rubber also is resistant to UV light. It is used in coating as well roofing materials, and foldable kayaks.
- Perfluoroelastomer (FFKM): This rubber has good resistance to chemicals and temperature. It is used in the fabrication of silicon wafers. It is also used in chemical processing and high-pressure seals.
- Thermoplastic Polyether-ester (YBPO): This rubber has high flexibility, and shows good resistance to chemicals. It is used as buffers, and in the production of belts and moldings.
Apart from the uses mentioned above, some other uses of synthetic rubber include,
- Production of weather balloons.
- In mattresses and pillows.
- In fuel for launching rockets during WWII.
- As it is waterproof, it is used in the manufacturing inflatable boats and diving suits.