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Chemistry of Essential Oils
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
Ethylene provides a good example of a petrochemical feedstock for the synthesis of lipids and polyketides. It can be oligomerized to provide a variety of alkenes into which functionalization can be introduced by hydration, oxidation, hydroformylation, and so on. Of course, telomerization can be used to provide functionalized materials directly.
Innovative industrial technology starts with iodine
Published in Tatsuo Kaiho, Iodine Made Simple, 2017
In order for fluoropolymers to manifest such superior properties, the role of iodine in their production process is very important. A typical production process of fluororesin is known as telomerization (see the diagram). (1) iodine (I2) and iodine pentafluoride (IF5) react in pentafluoroethylene to create pentafluoroethyl iodide (C2F5I), known as telogen. (2) the elongation reaction of tetrafluoroethylene is used to create a fluorocarbon chain from the telogen. (3) Ethylene is added to form perfluoroalkyl iodide, which modifies iodine into a hydroxyl, and fluorotelomer alcohol is obtained. (4) Ethyl acrylate is composed from perfluoroalkylethyl alcohol and acrylic acid, and by reacting this with other comonomers (acrylate, metacrylate, vinyl chloride, vinylidene chloride), water and oil repellent fluoropolymers are obtained [34]. In addition to C2F5I, heptafluoropropyl iodide((CF3)2CFI) is also used as a telogen.
Dietary exposure to perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS): a review of recent literature
Published in Toxin Reviews, 2018
Perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) are members of a chemical group known as perfluorinated compounds (PFCs). PFCs are fully anthropogenic; since the late 1940s they have been synthesized either via electrochemical fluorination (ECF) or telomerization (Schultz et al.2003). Millions of kilograms of these compounds have been produced worldwide annually. Their oil-, water-, and stains-repellent properties have made them useful in a wide range of applications, and many products contain these substances, e.g. textiles, carpets, upholstery, leather, food package, waxes, polishes, adhesives, paints, cosmetics, aviation hydraulic fluids, fire-fighting foams, and papers (Post et al.2012). Due to this widespread usage, PFCs are widely distributed in the environment.