Mixed, fluorine-containing

The mixed, fluorine-containing halomethyl cations, CFC12+,13 16 CF2C1+,14,15 CFBr2+,13,15 and CF2Br+ 13,15 have been generated in the gas phase by various... 

Boron trichloride has been reported to react with pseudohalide ions to give the mixed halogen-pseudohalogen ions BCl Z4 n (Z = CN-, NCO NCS, N3 ), none of which were isolated (107). However, only for the BC1 (CN)4 series were any individual mixed-ion llB resonances reported. The BX3OMe" ions [X = F (117), Cl (54), Br (54)) apparently disproportionate rapidly to give the BX4 ions. Early reports of fluorine-containing BF X4 species (X = halide, hydroxyl, etc.) have been summarized (162). 

The polymerization of unsaturated halohydrocarbons has been studied most extensively in the case of vinyl chloride and closely related compounds. Kainer 1S6) published a book recently on polyvinyl chloride and mixed polymers of vinyl chloride. In addition to chlorovinyl polymers, Schildknecht includes fluorovinyl polymers in his book Hl). Books covering plastics generally include material on the halohydrocarbon polymers (14, 144)- Several papers ISS, IS, 135,143) have been published in the last couple of years dealing with the polymerization of fluorine-containing compounds. Articles on polymerization of chloroprene 14 ), fluoroprene 1S8), chlorotrifluoroethylene 140), tetrafluoroethylene 1S9), vinylidene fluoride (157), and dichlorodifluoroethylene 1S7) have appeared in recent years. 

By analogy with photosensitive anodic films appearing over the surface of silicon during its treatment in fluorine-containing electrolytes, it can be suggested that the built-in film represents a mixed phase of electrochemical reaction products or results from the anodized surface amorphization [27,28]. In its turn, this indicates that under potentiostatic conditions the chemical processes at the SiC/HF junction are predominant. The results obtained emphasize that not every porous-like phase formed as a result of SiC anodization can be considered as PSC. 

Fuels that contain potentially harmful chemicals may produce effluents that contain hazardous materials. For example, fuels containing benzene could produce benzene in the exhaust under certain conditions. Since benzene is a hydrocarbon, it is generally easy to completely destroy if there is adequate oxygen, temperature, and mixing. Fuels containing chlorine or fluorine can produce dioxins and furans that are toxic. These are not as easy to eliminate from the exhaust, so some type of posttreatment system is often required to minimize these pollutants to acceptable levels. 

The so-called anode effect on carbon electrodes in fluoride-containing melts is probably the most vivid manifestation of a dielectric FS. This phenomenon was first related to the industrial electrolysis of aluminium in Hall-Heroult cells and, thus, is widely known for more than a 100 years. Nevertheless, a generally acknowledged theory is not achieved yet. Several possible causes have been considered nonwettability of the electrode surface, electrostatic repulsion of the bubbles of the gas evolved at the anode, hydrodynamic crisis of the gas evolution and, finally, the formation of a fluorocarbon dielectric film [18-20]. This latter explanatimi had been developed since then, mainly by Japanese researchers, relatively to the electrochemical production of fluorine [21]. A fluorocarbon film is now widely recognized as a cause of the anode effect both in fluoride and in mixed fluoride-containing electrolytes. 

Coswami, G. et al. (1990) Phase formation during sintering of magnesium and fluorine containing raw mix in cement rotary kiln. Zement-Kalk-Gips 43,253-256. 

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]. 

The fluorine containing compounds are added to the raw cement mix to accelerate the formation of cement minerals. The effect of additionof fluorides sueh as LiF, NaF and KF on the reactions in the system CaC03-Si02 has been followed by DTA.t l The results are shown in Fig. 7. In the absence of the additions, the curve (solid line) shows a slope at about 920°C while those treated with the fluorides exhibit a slope at a temperature of about 700°C, indicating early commencement of reactions. The effectiveness of other mineralizers have also been examined by DTA. The influence of mineralizers such as ZnO, CuO, and Mn02 on the formation of alite from a mixture of calcium carbonate and a silica-bearing material such... 

Mixed systems containing fluorinated surfactants and hydrocarbon surfactants are currently investigated for several theoretical and practical reasons ... 

The anionic fluorinated surfactant (SPFO) forms with the nonionic or the amphoteric hydrocarbon surfactant mixed micelles containing both types of surfactants. Both systems exhibit a negative deviation from ideality. Changes of the F and H chemical shifts of the two surfactants upon mixing are consistent with pseudophase diagrams, calculated from the cmc dependence on the fluorinated surfactant mole fraction. The interpretation of data was based a modified regular solution theory and the phase-separation model. 

Perfluorinated acid fluorides containing heteratoms are also accessible by ECF. Long-chain perfluorinated acid fluorides produced by ECF containing nitrogen (10—12), oxygen (13), and sulfur (14,15) have been reported. The fluorinated mixed sulfonic acid—carboxyflc acid precursors are also known. ECF of hydrocarbon sultones has led to formation of FS02(CF2) C0F, where n = 2,3 (16). 

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