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Polyvinyl chloride is produced from its monomer, vinyl chloride ( chemical formula C H2= C H Cl). PVC is a hard plastic that is made softer and more flexible by the addition of phthalates (plasticizers).
There are many uses for PVC including vinyl siding, gramophone records (hence the ones made of this material are sometimes called vinyl records) pipe/plumbing/conduit fixtures, bean bags; and, in its soft form, for clothing, upholsteryUpholstery is the work of providing furniture, especially seats with padding, springs, webbing, and fabric or leather covers. Classes Furniture upholstery Automobile upholstery Marine upholstery Specific projects Slipcover Canvaswork Throw pillow Tools Up (car seats), etc.
Polyvinyl chloride was accidentally discovered on at least two occasions in the 19th century, first in 1838 by Henri Victor RegnaultHenri Victor Regnault ( July 21, 1810 January 19, 1878) was a French chemist and physicist best known for his careful measurements of the thermal properties of gases. Born in Aix-la-Chapelle in 1810, he moved to Paris following the death of his parents at and in 1872 by Eugen Baumann . On both occasions, the polymer appeared as a white solid inside flasks of vinyl chloride that had been left exposed to sunlight. In the early 20th century, the RussiaThe Russian Federation ( Russian: , transliteration: Rossiyskaya Federatsiya or Rossijskaja Federacija , or Russia (Russian: , transliteration: Rossiya or Rossija , is a country that stretches over a vast expanse of eastern Europe and northern Asia. Withn chemist Ivan Ostromislensky and Fritz KlatteFritz Klatte ( 1880- 1934) was the discoverer of polyvinyl acetate, with German patent (GP 281687 1912) for its preparation from acetylene gas. Polyvinyl chloride (PVC) was discovered by French physicist Henri Victor Regnault, and Klatte designed the prod of the GermanThe Federal Republic of Germany ( German: Bundesrepublik Deutschland is one of the world's leading industrialized countries, located in the middle of the European Union. It is bordered to the north by the North Sea, Denmark and the Baltic Sea, to the east chemical company Griesheim-Elektron both attempted to use PVC in commercial products, but difficulties in processing the rigid, sometimes brittle polymer blocked their efforts.
In 1926, Waldo SemonWaldo Lonsbury Semon ( September 10, 1898- May 26, 1999) was a renowned American inventor born in Demopolis, Alabama. Semon put his name into the history books for inventing vinyl, the world's second most used plastic. He found the formula for vinyl by mi of B.F. Goodrich developed a method to plasticize PVC by blending it with various additives. The result was a more flexible and more easily processed material that soon achieved widespread commercial use.
Most vinyl products are believed to be generally harmless when used properly. However, some of the additives and softener s leech out of certain vinyl products. Even though soft PVC toys have been made for babies for years, studies find that these additives leech out of soft toys into the mouths of the children chewing on them. Vinyl IV bags used in neo-natal intensive care units have also been shown to leach DEHP (di-2-ethyl hexyl phthalate), a phthalate additive. In Europe, phthalate additives in PVC toys for children under the age of three have been banned and in the USA, most companies have voluntarily stopped manufacturing PVC toys for this age group or have eliminated the phthalates. However, alternative softeners have not been properly tested to determine whether they are safe. Other vinyl products like brand new car interiors, shower curtains, and flooring, to name a few, initially release chemical gases into the air. Some studies indicate that this outgassing of additives may contribute to health complications, but the information on this is preliminary and needs further study.
According to some medical studies, the plasticizers added to PVC may cause chronic conditions such as Raynaud's syndrome, scleroderma, cholangiocarcinoma, angiosarcoma, brain cancer and acroosteolysis .
In the late 1960's, Dr. John Creech, and Dr. Maurice Johnson, were the first to clearly link and recognize the carcinogenicity of vinyl chloride monomer to humans; workers in the polyvinyl chloride polymerization section of a B.F. Goodrich plant near Louisville, Kentucky, were diagnosed with liver angiosarcoma, a rare disease. Since that time, studies of PVC workers in Australia, Italy, Germany, and the U.K. have all associatied occupational cancers with exposure to vinyl chloride.
The environmentalist group Greenpeace has advocated the global phase-out of PVC because dioxin is produced as a byproduct of vinyl chloride manufacture.
In 2004, a joint Swedish-Danish research team found a very strong link between allergies in children and the phthalates DEHP and BBzP, commonly used in PVC.
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