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  2. Per- and polyfluoroalkyl substances - Wikipedia

    en.wikipedia.org/wiki/Per-_and_polyfluoroalkyl...

    Skeletal structure of PFOS, an effective, persistent and bioaccumulative fluorosurfactant A physical sample of PFOA, appearing as a white solid as seen here in a relatively pure form. It is commonly referred to as the main harmful PFAS chemical and PFOA is responsible for many of the negative health effects commonly associated with PFAS.

  3. Perfluoroalkoxy alkane - Wikipedia

    en.wikipedia.org/wiki/Perfluoroalkoxy_alkane

    Perfluoroalkoxy alkanes (PFA) are fluoropolymers. They are copolymers of tetrafluoroethylene (C 2 F 4) and perfluoroethers (C 2 F 3 OR f, where R f is a perfluorinated group such as trifluoromethyl (CF 3)). The properties of these polymers are similar to those of polytetrafluoroethylene (PTFE). Compared to PTFE, PFA has better anti-stick ...

  4. Performic acid - Wikipedia

    en.wikipedia.org/wiki/Performic_acid

    Performic acid (PFA) is an organic compound with the formula CH 2 O 3. It is an unstable colorless liquid which can be produced by mixing formic acid with hydrogen peroxide . Owing to its oxidizing and disinfecting action, it is used in the chemical, medical and food industries.

  5. Perfluorooctanoic acid - Wikipedia

    en.wikipedia.org/wiki/Perfluorooctanoic_acid

    In a U.S. Food and Drug Administration (USFDA) study, lipophobic fluorotelomer-based paper coatings (which can be applied to food contact paper in the concentration range of 0.4%) were found to contain 88,000–160,000 parts per billion PFOA before application, while the oil from microwave popcorn bags contained 6–290 parts per billion PFOA ...

  6. Paraformaldehyde - Wikipedia

    en.wikipedia.org/wiki/Paraformaldehyde

    Paraformaldehyde (PFA) is the smallest polyoxymethylene, the polymerization product of formaldehyde with a typical degree of polymerization of 8–100 units. Paraformaldehyde commonly has a slight odor of formaldehyde due to decomposition.

  7. Polyoxymethylene - Wikipedia

    en.wikipedia.org/wiki/Polyoxymethylene

    To make polyoxymethylene homopolymer, anhydrous formaldehyde must be generated. The principal method is by reaction of the aqueous formaldehyde with an alcohol to create a hemiformal, dehydration of the hemiformal/water mixture (either by extraction or vacuum distillation) and release of the formaldehyde by heating the hemiformal.

  8. 'Not our best, but closer' - how high can Man City finish? - AOL

    www.aol.com/not-best-closer-high-man-220555005.html

    After a dreadful run of form during November and December, Manchester City looked more like their old selves as they thrashed Ipswich 6-0 on Sunday.

  9. Food and Drug Administration - Wikipedia

    en.wikipedia.org/wiki/Food_and_Drug_Administration

    The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services.The FDA is responsible for protecting and promoting public health through the control and supervision of food safety, tobacco products, caffeine products, dietary supplements, prescription and over-the-counter pharmaceutical drugs (medications), vaccines ...