Poly chloro-trifluoroethylene

Method A An aromatic or unsalurated compound and S02FCI or CC13F were placed in a poly(chloro-trifluoroethylene) reactor fitted with a Teflon stirrer and a Teflon-coated thermocouple. The mixture was cooled to — 25 C. Then a solution of VF5 in an equal volume of the solvent was added pordonwise, with stirring, at such a rate that the temperature was maintained at less than — 20 C. When the addition was complete, the mixture was poured onto crushed ice, the organic layer was separated, washed with cold H20, and dried (MgS04 or CaCl2). and the solvent was removed by distillation. 

Poly(chloro trifluoroethylene) is another macromolecule which can, at pressures as little as 10 MPa, be crystallized into extended chain crystals139). Little is known about the detailed process, but a high mobility state was assumed to explain the special crystallization 19). The only crystal structure reported is hexagonal with 17 monomers in the repeat distance along the chain axis. Conditions for conformational mobility seem favorable. 

Scheme 4.4 Synthesis of poly(chloro-trifluoroethylene) (PCTFE).

Figure Thermogram in an inert atmosphere of a poly(ethylene-alt-chloro-trifluoroethylene) sample using a heating rate of tCf C/min.

Poly(l-Chloro-l,2,2-Trifluoroethylene). Poly(l-chloro-l,2,2-trifiuoroethylene consists of linear chains in which the predominant repeating unit is... 

The matter of the head-to-head, tail-to-tail polymerization of vinyl fluoride, vinylidene fluoride, and trifluoroethylene and the copolymerization of vinyl fluoride with vinylidene chlorofluoride and l-chloro-2-fluoroethylene has been extensively studied by Cais and Kometani [24-27] and by Bruch, Bovey, and Cais [28]. The synthesis of pure head-to-tail poly(trifluoroethylenes) is described in Ref. [25]. Isomers of poly(vinyl fluoride) with controlled regiosequence microstructure are discussed in Ref. [27]. 

CO2 at or near room temperature and at pressures typically below 600 bar can dissolve many poly(dimethyl) and poly(phenylmethyl) siloxane, perflu-oroalkylpolyethers, chloro- and bromo-trifluoroethylene polymers, and poly(per-fluoropropylene oxide) (21,42-47). The polymers reported to have solubility in CO2 all possess some degree of polarity due to oxygen or other electronegative groups, such as chlorine or bromine, incorporated into the backbone of the polymer. In addition, the high solubility of the silicones in CO2 is likely due to the very flexible nature of these polymers that endows them with much larger free volumes than other polymers. 

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