Fluorocarbons manufacturing methods

Almost all of the biomedical research done in the 25 years following the liquid-breathing work was conducted with commercially available fluorocarbons manufactured for various industnal uses by the electrochemical Simons process (fluonnation in a hydrofluoric acid solution) or the cobalt fluoride process (fluori-nation with this solid in a furnace at about 200 C) These processes tended to yield many by-products, partly because they were, to some extent, free radical reactions and partly because it was difficult to easily achieve complete fluonnation Aromatic hydrocarbons gave better products with the cobalt tnfluonde [73] method, whereas saturated hydrocarbons yielded better products with fluonnation using diluted or cooled gaseous fluorine (Lagow) Incompletely fluormated matenal was either... 

Fluorocarbons are made commercially also by the electrolysis of hydrocarbons in anhydrous hydrogen fluoride (Simons process) (14). Nickel anodes and nickel or steel cathodes are used. Special porous anodes improve the yields. This method is limited to starting materials that are appreciably soluble in hydrogen fluoride, and is most useflil for manufacturing perfluoroalkyl carboxyflc and sulfonic acids, and tertiary amines. For volatile materials with tittle solubility in hydrofluoric acid, a complementary method that uses porous carbon anodes and HF 2KF electrolyte (Phillips process) is useflil (14). 

The electrochemical production of fluorocarbons was developed by Simons (112) and is the method applied by the Minnesota Mining and Manufacturing Co. A pilot plant study of this method was reported in Simon s book (110). 

Building material and method of its manufacture is included in invention. Product includes an extrudable thermoplastic (e.g., PVC of the above formulation) or thermosetting substrate having a fluorocarbon-based capstock layer... 

Method 413 has recently become controversial in the fact that the manufacture of the common extraction solvent used in the method, 1,1,2-trichlorotrifluoroethane (TCTFE), itself a fluorocarbon (Freon 113), is banned. The attributes of TCTFE are such that it enabled this method to move from a purely gravimetric approach, EPA Method 413.1 (Gravimetric, Separatory Funnel Extraction), to an instrumental approach whereby the carbon-to-hydrogen stretching frequency in the infrared spec-... 

---