Royal Society of Chemistry Fluorocarbon and Related Chemistry: Volume 3 (Specialist Periodical Reports - Fluorocarbon and Related Chemistry)

Reflecting the growing volume of published work in this field, researchers will find this book an invaluable source of information on current methods and applications. Excerpt. © Reprinted by permission. All rights reserved. Fluorocarbon and Related Chemistry Volume 3 A Review of the Literature Published During 1973 and 1974 By R. E. Banks, M. G. Barlow The Royal Society of Chemistry Copyright © 1976 The Chemical Society All rights reserved. ISBN: 978-0-85186-524-9 Contents Chapter 1 Saturated Fluorocarbons, Fluorocarbon Hydrides, and Fluorocarbon Halides By R. E. Banks, 1, Chapter 2 Per-and Poly-fluorinated Olefins, Dienes, Heterocumulenes, and Acetylenes By M. G. Barlow and D.R. Taylor, 49, Chapter 3 Aliphatic Per-and Poly-fluorinated Carbonyl and Thiocarbonyl Compounds By A. E. Tipping and V. J. Davis, 127, Chapter 4 Per-and Poly-fluorinated Aliphatic Derivatives of the Main-Group Elements By R. E. Banks, 187, Chapter 5 Per-and Poly-fluorinated Aliphatic Derivatives of the Transition Elements By R. Fields, 308, Chapter 6 Per-and Poly-fluorinated Aromatic Compounds By J.M. Birchall and W. T. Flowers, 356, Appendix, 468, Author Index, 471, CHAPTER 1 Saturated Fluorocarbons, Fluorocarbon Hydrides, and Fluorocarbon Halides BY R. E. BANKS 1 Fluorocarbons More information concerning the preparation, properties, and applications (lubricants, seals, and bearing; cathode components for high-energy batteries; g.s.c. stationary phase; precursor of diamonds and fluorinated diamonds) of poly(carbon monofluoride) ('graphite fluoride') is now available. Detailed experimental procedures for the direct fluorination of regular or pyrolytic graphite using autoclave, fluidized-bed, or normal flow techniques are now to hand; production of snow-white superstoicheiometric poly(carbon monofluoride), [CF1.12[plus or minus]0.03]n, by the flow or fluidized-bed method demands a reaction temperature range of 627 [plus or minus] 3 °C, outside which either carbon tetrafluoride plus soot (at > 630 °C) or black-to-grey substoicheiometric material (e.g. black [CF0.68]n at 540 °C) are formed. At atmospheric pressure, fluorine does not appear to attack graphite at temperatures below 450°C, but at pressures greater than 225 lbf in-2, reaction occurs spontaneously at 20°C and can lead to a violent explosion if the rate of introduction of fluorine into the autoclave is not regulated carefully. No decomposition of superstoicheiometric poly(carbon monofluoride) appears to occur at 650 — 700 °C in the presence of fluorine. More structural data for poly(carbon monofluoride) are available following an X-ray powder diffraction study on material pressed at 20 kbar and 150 °C and determination of the n.m.r. absorption mode second moment of commercial Fluorographite samples (see Vol. 2, p. 1, ref. 2) of stoicheiometry CFl.06 and CF1.15; the results of the latter study indicate that the most plausible layer structure comprises an infinite array of cis-trans-linked cyclohexane boats . Direct fluorination (flow method) of 'graphite oxide', [C8O2(OH)2]n (from graphite/KMnO4-NaN03-H2SO4 at 66 °C) at 20 °C and 1 atm yields a powdery, pale grey, thermally (above 50 °C) and hydrolytically unstable 'oxyfluoride' (16.25 — 22.4% F; λmax 1095 cm-1 (C — F stretch); c[florin].1 [C4F]n 1090 cm-1, [CF1.12[plus or minus]0.03]n 1217s ([??]C — F), 1342m, 1072w (peripheral CF2) cm-1}.1 Full details have been published of the direct fluorination of hydrocarbon polymersl6 by the so-called LaMar procedure, the principal feature of which is inhite dilution initially with helium or nitrogen followed by gradient changes of fluorine concentration ; with substrate particle sizes greater than lo0 mesh a hydrocarbon core is retained, and large fabricated items such as polyethylene bottles can be given a fluorocarbon skin of thickness ca. 0.2. Complete, or almost complete, fluorination of finely powdered (< 100 mesh) polyethylene, polypropylene, poly(ethylene-co-