Silica interaction with fluorine

Arsenic trioxide reacts violently and nitrogen oxide ignites in excess fluorine. Bubbles of sulfur dioxide explode separately on contacting fluorine, while addition of the latter to sulfur dioxide causes an explosion at a certain concentration [1], Reaction of fluorine with dinitrogen tetraoxide usually causes ignition [2], Interaction with carbon monoxide may be explosive. Anhydrous silica incandesces in the gas, and interaction with liquid fluorine at — 80°C is explosive [3,4], Boron trioxide also incandesces in the gas [3],... 

Prior to the first report of platinum hexafluoride had observed that when platinum or platinum salts were fluorinated in silica apparatus a deep red solid was produced. This solid sublimed in a good vacuum, below 100. It was evidently an oxyfluoride, the oxygen being derived from interaction of fluorine with the siUca SiOg -f- 2Fg —> SiF + Og, since fluorination of platinum in nickel apparatus did not give it. 

Surface interaction of fluorine with silica- and alumina-based materials. 

The energy of interaction of these molecules with surface hydroxyl groups is 30-45% higher than for silica gels with methylated or fluorinated surfaces. 

The curing of an epoxy resin adj acent to an embedded silica optical fibre was monitored in situ by evanescent wave spectroscopy. The epoxy resin was partially fluorinated and had a lower refractive index than the silica fibre. The lower refractive index of the epoxy resin allowed the silica optical fibre to be used as a waveguide for the internal reflection of the near-IR light. The epoxy resin curing was determined as a function of time and temp, by analysis of the near-IR spectmm from the epoxy adj acent to the fibre obtained by the interaction of the evanescent wave that occurred at each internal reflection with the low refractive index epoxy resin. The results obtained showed that epoxy ring-opening and... 

Then they used these fluorinated PBIs for the preparation of the hybrid nanocomposite by mixing it with a silica precursor, tetraethoxysilane (TEOS), in a DMAc solution followed by hydrolysis and solution casting (Figure 5.19). The compatibility of the fluorine-containing PBI copolymer with the inorganic silica phase was good, and the bonding site enhanced the interfacial interaction between PBI chains and silica nanoparticles [33]. 

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