Vinylidene Fluoride-Hexafluoropropene Copolymer

In a more specialized approach, IL phases have been immobilized in membrane materials. Although the primary driver of this work was the use of these materials as electrochemical devices, they have also been investigated for catalytic applications [20]. Membrane materials composed of air-stable, room-temperature ILs and poly(vinylidene fluoride)-hexafluoropropene copolymers were prepared with the incorporation of the active catalyst species in the form of palladium on activated carbon. Optical imaging revealed that the prepared membranes contained a high dispersion of the palladium catalyst particles. Studies on the materials included evaluating their gas permeability and their catalytic activity for the hydrogenation reaction of propene. 

Crosslinking of CR, chlorobutyl rubber, chlorinated acryl rubber, epichlorohydrin rubber, ethylene-epichlorohydrin copolymer rubber, PVC, chlorinated ethylene and vinylidene fluoride-hexafluoropropene copolymer rubbers in presence of metal compounds such as MgO was studied in detail to elucidate mechanism, variables affecting reaction, points of crosslinking and relative reactivity of rubbers. Control techniques using retarders or accelerators, depending on halogen activity, were proposed. 17 refs. 

B.p. — 29X. Monomer used to form polymers (only under rather drastic conditions) or copolymers with C2F4 and vinylidene fluoride, CH2 = CF2. Hexafluoropropene may be prepared by thermal decomposition of CF3CF2CF2C02Na or is prepared commercially by low pressure pyrolysis of C2F4. 

Teblina et al. [26] studied the kinetics of radical polymerization of metha-crylic acid in the presence of a hexafluoropropene-vinylidene fluoride copolymer. The polymerization rate increased with conversion. A grafted copolymer was formed by a reaction analogous to eqn. (40) (with F instead of... 

Various copolymers of the fluorinated monomers have been prepared [243]. Copolymers of tetrafluoroethylene and hexafluoropropene have under vacuo a stability close to that of teflon (Fig. 66). Copolymers with trifluoronitroso me thane have a lower stability than PTFE (Figs. 66 and 67). The copolymer of vinylidenefluoride and hexafluoropropene is one of the most stable elastomers available at the present time (Fig. 66 and Table 12). For a typical copolymer containing 70% vinylidene fluoride, the rate of weight loss is 0.04% per min at 350°C and the activation energy is 57 to 46 kcal mole"1, according to Wright [243]. 

The exact location of the plasticizer is frequently evaluated to better understand the structure of plasticized polymers. In poly[(vinylidene fluoride)-co-hexafluoropropene], VDF/HFP plasticized with dibutyl phthalate, SAXS measurements indicate that DBP resides in the amorphous zone outside the lamellar stacks. If ciystallization is slow the inclusion of DBP inside the lamellar stacks is also possible. In another contribution for the same copolymer, plasticizer was also found in amorphous phase close to the interface with crystalline stmctures which was evidenced by almost constant spacing in the range of tricresyl phosphate studied.In the plasticized PVC, the plasticizer molecules were found in the amorphous area but were also present in the interlamellar, intefibrillar, inter-spheralitic regions and in the amorphous fold surfaces. ... 

In response to a market-driven need, Pennwalt developed a more flexible version of the fluoropolymer for certain applications. This fluoropolymer was introduced in 1984 under the trademark KYNAR FLEX 2800. KYNAR FLEX 2800 is a copolymer of vinylidene fluoride and hexafluoropropene (HFP). 

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