Demnum® fluids

For comparison, oxetanes are oligomerised in an analogous way to give intermediate polyfluoro-polyethers that are then further fluorinated to give perfluoro-polyethers in the process for the production of Demnum fluids (Daikin Co.) [188] (Figure 8.59). 

Perfluoropolyethers have found widespread use as high-performance lubricants and several companies manufacture a range of these materials (Krytox , Du Pont Fomblin , Montefluos Demnum , Daikin). The Fomblin fluids and Krytox require the use of fluorine in the finishing stages [81] whilst Demnum is synthesised by polymerisation of the fluorooxetane 16 followed by per-fluorination using fluorine (Fig. 27) [82]. 

Ohsaka, Y. Perfluoropolyether fluids (Demnum) based on oxetanes. In Organofluorine Chemistry. Principles and Commercial Applications Banks, R.E., Ed. Plenum Press New York, 1994 pp 463 67. 

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