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Polytetrafluoroethylene is used as a non-stick coating for pans and other cookware. It is non-reactive, partly because of the strength of carbon–fluorine bonds, so it is often used in containers and pipework for reactive and corrosive chemicals. Where used as a lubricant, PTFE reduces friction, wear, and energy consumption of machinery.
A convenient, safe method for generating TFE is the pyrolysis of the sodium salt of pentafluoropropionic acid: [6]. C 2 F 5 CO 2 Na → C 2 F 4 + CO 2 + NaF. The depolymerization reaction – vacuum pyrolysis of PTFE at 650–700 °C (1,200–1,290 °F) in a quartz vessel – is a traditional laboratory synthesis of TFE.
Symptoms. fever, shaking chills, arthralgias, myalgias, headache, and malaise. Polymer fume fever or fluoropolymer fever, also informally called Teflon flu, is an inhalation fever caused by the fumes released when polytetrafluoroethylene (PTFE, known under the trade name Teflon) reaches temperatures of 300 °C (572 °F) to 450 °C (842 °F). [ 1 ]
e. Air pollution is the contamination of air due to the presence of substances called pollutants in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. [ 1 ] It is also the contamination of the indoor or outdoor environment either by chemical, physical, or biological ...
Per- and polyfluoroalkyl substances are a group of synthetic organofluorine chemical compounds that have multiple fluorine atoms attached to an alkyl chain. Different organizations use different definitions for PFAS, leading to estimates of between 8,000 and 7 million chemicals within the group. The EPA toxicity database, DSSTox, lists 14,735 ...
Smog, or smoke fog, is a type of intense air pollution. The word "smog" was coined in the early 20th century, and is a portmanteau of the words smoke and fog [1] to refer to smoky fog due to its opacity, and odor. [2] The word was then intended to refer to what was sometimes known as pea soup fog, a familiar and serious problem in London from ...
Phthalates are produced industrially by the acid catalysed reaction of phthalic anhydride with excess alcohol.The synthesis of diethyl phthalate is illustrative of this: . The properties of the phthalate can be varied by changing the alcohol, [12] allowing for an almost limitless range of products, although only around 30 are, or have been, commercially important.
You can help by adding missing items with reliable sources. This timeline of events related to per- and polyfluoroalkyl substances (PFASs) includes events related to the discovery, development, manufacture, marketing, uses, concerns, litigation, regulation, and legislation, involving the human-made PFASs.