Perfluoropolyethers, synthesis

Buhler, E. Dobrynin, A. V. DeSimone, J. M. Rubinstein, M. Light-Scattering Study of Diblock Copolymers in Supercritical Carbon Dioxide C02 Density-Induced Micellization Transition. Macromolecules 1998, 31, 7347-7355. Bunyard, W. C. Romack, T. J. DeSimone, J. M. Perfluoropolyether Synthesis in Liquid Carbon Dioxide by Hexafluoropropylene Photooxidation. Macromolecules 1999, 32, 8224-8226. 

Scheme 9.5 Perfluoropolyether synthesis through photooxidation of hexafluoropropylene.

McLeod, M.C., McHenry, R.S., Beckman, E.J. and Roberts, C.B. (2003) Synthesis and stabilization of silver metallic nanopartides and premetallic intermediates in perfluoropolyether/C02 reverse micelle systems. Journal of Physical Chemistry B, 107 (12), 2693-2700. 

Work from our research group at the University of Texas on the synthesis of perfluoroethers and perfluoropolyethers by direct fluorination is revolutionizing and, in fact, has revolutionized this field. Our laboratory has been responsible for putting at least 30 new perfluoropolyethers into the literature and in some cases they are now on the commercial chemical market. Exfluor Research Corporation prepared several hundred new perfluoropolyethers expanding upon the work from... 

H2O, H00CCF20(CF2CF20) .2CF2C00H +2CF3COOH + 2HF Figure 14.7. Synthesis of functional perfluoropolyethers. 

A promising and extremely interesting new area of research is the synthesis of perfluoropolyethers by the reaction of elemental fluorine with hydrocarbon polyethers (34, 35). An extensive recent research program at the University of Texas at Austin has succeeded in establishing the generality of this approach. In the initial study, polyethylene oxide was reacted with elemental fluorine under... 

The high-molecular-weight perfluoropolyethers obtained in the first step have excellent thermal stability (TGA initial decomposition >370°C) and chemical resistance and are true fluorocarbon elastomers that are, in contrast to polytetrafluoroethylene, flexible. Other methods for the synthesis of perfluoropolyethers and functionalized perfluoropolyethers are under development in our laboratories. 

Hexafluoropropylene oxide is an important intermediate in fluoroorganic synthesis. It is useful in the production of surfactants, perfluoropolyether oils, solvents, perfluorinated alkylvinyl ethers, and other materials. 

Li GX, Wie JJ, Nguyen NA, Chung WJ, Kim ET, Char K, Mackay ME, Pyun J (2013) Synthesis, self-assembly and reversible healing of supramolecular perfluoropolyethers. J Polym Sci Polym Chem 51(17) 3598-3606... 

The use of water-in-C02 microemulsions in particle synthesis has been extended recently to palladium [425]. An aqueous solution of PdCl2 was dispersed in supercritical CO2, and the surfactants NaAOT and (about twice its concentration of) perfluoropolyether phosphate (PFPE-PO4) were used for microemulsion stabilization. As in other similar cases, the formation of microemulsion and particle synthesis took place within a high pressure cell (at 200 atm). Reduction of palladium was caused by hydrogen gas (unlike in other similar investigations) because of its... 

A recent work [445] used the water-in-C02 microemulsion technique for the synthesis of silver halides using NaAOT as the surfactant and perfluoropolyether phosphate as the co-surfactant. The reaction between AgN03 and NaX (X = I, Br, Cl) in H2O took place in a pressurized (200 atm) cell. The particle size, when measurable, was found to be 3-4 nm. 

Phosphate surfactant Fig. 4 Synthesis of perfluoropolyether-based intermediates and surfactants... 

The H-NMR (300 MHz) analyses performed by using a CDCl3/l,l,2-trichloro-l,2,2-trifluoroethane (TCTFE) mixture as the solvent were applied for the monitoring of the degree of synthesis and structural investigation of the UPRs modified with perfluoropolyethers [71]. The number-average molecular weight (Mn) of the used telechelic-fiuorinated macromers based on perfluoropolyethers (HO-Rh-PFPE-Rh-OH) was determined by F-NMR. 

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