Fluorination liquid containment

To determine the suitability of fluorinated HDPE containers as packaging material for the solvent-based formulations, the containers were placed in well-ventilated ovens at 50°C for 28 days. During this period the mass loss of the contents was monitored. To date more than 130 liquid crop protection chemical formulations have been evaluated at the AEC by this method with at least 91 of them having serious permeation problems through the untreated HDPE containers. In only two cases fluorinated containers did not have acceptable barrier properties. 

Polyester cloth-backed flat PP sheets (fleece-backed sheets) are normally used to manufacture large reservoirs for liquid containment purposes. Typically, such reservoirs are reinforced on the outside with fiberglass. The polyester mat backing serves as an adhesion key between the PP and the fiberglass resin. Fluorine surface activation can be used as a substitute for the fleece-backed material at a considerable cost-saving. Table 16.12 shows a comparison between the adhesive performance of the materials with two polyester resins. 

V. Strehmel, B. Stiller, B. Strehmel, A. M. Sarker, and D. C. Neckers, Fluorinated Distyrylbenzenes Containing Copolymers for Photoinduced Formation of Anisotropic Materials as Photoalignment Layers for Liquid Crystals. In Photoinitiated Polymerization, Vol. 847, K. D. Belfield and J. V. Crivello, Eds., American Chemical Society, Washington, DC, 2003, p. 482. 

Hydrophobicity or hydrophilicity is also an important property, which can be controlled by selecting an appropriate cation and anion combination. Longer alkyl chains on the cation have been found to result in increased hydrophobicity [80, 81]. Hydrophobicity also depends on the identity of the anion. For example, ionic liquids containing fluorinated anions such as tetrafluoroborate and hexafluorophosphate are considerably more hydrophobic than the halide salts of the same cation. Ionic liquids containing the bis(trifluoromethanesulfonyl)amide anion [NTf2] are extremely hydro-phobic whereas their non-fluorinated analogues are sometimes completely miscible with water [82], The immiscibility of the ionic liquid with water or other solvents may be useful for phase separations, but it also has implications on the greenness of the ionic liquid in the event of accidental release into the environment [80],... 

Figure 14 Fluorinated liquid crystal containing trifluoromethyl or fluorophenyl moieties.

F.B. Meng, C. Du, N.Y. Zhou, X.Z. He, H.B. Chen, Synthesis and characterization of fluorinated liquid-crystalUne elastomers containing chiral liquid-crystalUne crosslinking units, Eur. Pol. J. 49 (10) (2013) 3392-3401. 

Such trailer mounted units consist of three concentric tanks. The liquid fluorine is contained in an inner baffled tank made of Monel metal or stainless steel. The inner tank is enclosed by a stainless steel tank filled with liquid... 

The subject of safety devices for a liquid-fluorine storage container should be considered individually for each location and application. In the case at hand, a gauge is included in the gas-phase piping, and this gauge incorporates a warning device set for 10 psi. Should the fluorine pressure reach this level, an alarm is sounded in the test cell control room and simultaneously in the Security Guard office, in order to provide protection for periods when the base is not in operation. Further protection is afforded by a gas-phase rupture disc with a burst value of 60 psi. The vent from the rupture disc, as well as the normal vent, is piped to a burner stack where it is burned in combination with propane gas. 

IPS mode is useful not only for large TVs, but has also been used in many small-and medium-sized panels and touch panel display types, and the future will bring more useful applications. Figure 1.20 shows the correlation between Ae and yi/ 22. and the improvement of the response time of IPS mode liquid crystal materials that contain fluorinated liquid crystal compounds from the third to fifth generations of materials is very obvious. 

Photofluorination of Nylon 6 in liquid hydrogen fluoride furnishes a C-fluorinated polyamide containing 1-25 g atom of F per unit mol. 

Weight gain is noted with some chlorinated and fluorinated liquids that contain no hydrogen (Ref 82). The weight increase decreases with increasing crystallinity (Ref 78). 

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