Fluorotélomère

Fluorotelomers are fluorocarbon-based oligomers, or telomers, synthesized by telomerization. Some fluorotelomers and fluorotelomer-based compounds are a source of environmentally persistent perfluorinated carboxylic acids such as PFOA and PFNA, while others are under extended investigation. There are many broad categories of fluorotelomers: Fluorotelomer alcohols (FTOH) Fluorotelomer ethoxylates (FTEO) Fluorotelomer fumarates Fluorotelomer methacrylates (FTMAC) Fluorotelomer sulphonates (FTS) In the radical telomerization of fluorotelomer molecules, a variety of fluorinated alkenes can serve as unsaturated taxogens including tetrafluoroethylene, vinylidene fluoride, chlorotrifluoroethylene, and hexafluoropropene. However, many fluorotelomers, such as fluorotelomer alcohols, are fluorocarbon-based because they are synthesized from tetrafluoroethylene. In addition to alcohols, synthetic products include fluorotelomer iodides, olefins, and acrylate monomer. Polymerized acrylate from iodide and alcohol monomers represent >80% of the global manufacture and use of fluorotelomer-based products. Fluorotelomers are used in fire-fighting foams, grease-resistant food packaging, leather protectants and stain-resistant carpeting, textiles, anti-fogging sprays and wipes. Fluorotelomers are applied to food contact papers for their lipophobicity, making paper resistant to absorbing oil from fatty foods. Fluorotelomer coatings are used in microwave popcorn bags, fast food wrappers, candy wrappers, and pizza box liners. Fluorotelomers that contain PFOA precursors can be metabolized into, and degrade to, PFOA, a persistent global contaminant found in people in the low-parts per billion range. Toxicologists estimate microwave popcorn, because of the high heat and coated bag, could account for about 20% of the PFOA levels measured in an individual consuming 10 bags a year if 1% of the fluorotelomers are metabolized to PFOA. PFOA is also formed as an unintended byproduct in the production of fluorotelomers, and is thus present in finished goods treated with fluorotelomers, including those intended for food contact.