GB1571356A - Polyfluoroallyloxy compounds their preparation and copolymers therefrom - Google Patents

Description

(54) POLYFLUOROALLYLOXY ('OMP()UNl)S, 'TItEIK PREPARATION AND COPOLYMERS THEREFROM (71) We, E. I. DU PONT DE NEMOURS AND COMPANY, a Company organised and existing under the laws of the State of Delaware, United States of America, of Wilmington, Delaware, United States of America, do hereby declare the invention, for which we pray that a patent may be grunted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to polyfluoroallyloxy compounds, processes for their preparation and copolymers prepared therefrom.

1. U.S. Patent 2,856,435 discloses the preparation of perfluoroallyloxy-1,1 dihydroperfluoroalkanes from 3-chloropentafluoropropene and a 1,1 dihydroperfiuoroalkanol in alkaline medium, e.g.

2. U.S. Patent 2,671,799 discloses a process for replacing the chlorine in perfluoroallyl chloride (3-chloropentafluoropropene) with methoxy, cyano, iodo and nitrate groups, e.g.

CF2=CFCF2Cl + NaOCH3 # CF2=CFCF2OCH3 3. M. E. Redwood and C. J. Willis, Canal. J. Chem., 45, 389 (1967) describe the reaction of allyl bromide with cesium heptafluoro-2-propoxide to form 2allyloxyheptafluoropropane: CH2=CHCH2Br + (CF3)2CFO-Cse # CH2=CHCH2OCF(CF3)2 + CsBr 4. J. A. Young, Fluorine Chemistry Reviews, 1, 389-393 (1967) surveys the formation of perfluoroalkoxide anions by the action of alkali metal fluorides on perfluoroketones, perfluoroalkyloxiranes, perfluorocarboxylic acid fluorides and perfluoroalkyl fluorosulfates. References 5-9 which follow are examples of the nucleophilic reactions of perfluoroalkoxide anions.

5. U.S. Patent 3,450,684 discloses the preparation of fluorocarbon polyethers and their polymers by reaction of perfluoroalkanoyl fluorides with potassium or quaternary ammonium fluoride and hexafluoropropene epoxide.

6. U.S. Patent 3,674,820 discloses the reaction of fluoroketones with an alkali metal fluoride and an omega-haloalkanoic acid ester to form an omega-(perfluoroalkoxy) alkanoic acid ester, e.g.

(CF3)2CO + KF + Br(CH2)4CO2CH3 o (CF3)2CFO(CH2)4CO2CH3 7. U.S. Patent 3,795,684 also discloses the reaction of hexafluoroacetone with potassium fluoride and an omega-haloalkanoic acid ester.

8. U.S. 3,527,742 discloses the reduction of the compounds of Reference 6 to the corresponding alcohols and their esterification to polymerizable acrylates.

9. U.S. 3,799,992 discloses the preparation of (perfluoroalkoxy)vinyl compounds by reaction of a perfluoroketone with an alkali metal fluoride and a 1,2-dihaloethane, followed by dehydrohalogenation of the intermediate 2-perfluoroalkoxyhaloethane.

10. U.S. Patent 3,321,532 discloses the rearrangement of perfluoro-2-alkoxyalkanoyl fluorides to perfluoroalkoxyolefins by passage over a metal oxide at 1()0-40() C, e.g.

According to the present invention there is provided a polyfluoroallyloxy compound having the general formula

wherein X is -Cl or -F;

W and Z independently are -F or together are -CF2-; D independently is F, ,F o CF3 - C'O\ /CF cP3 C IC\ X \ CF2=CFCF2O or -RF where -RF is a linear or branched perfluoroalkyl of 1 to 10 carbon atoms, interruptable no more frequently than every second carbon atom by from 1 to 4 oxygen atoms, having 0 to 2 functional groups selected from -SO2F, -COF, -CO2H, -CO2R3, -Cl -OCF2CF=CF2 and -OCF2CO2R3 where R3 is -CH3 or -QH5 E independently is -F, -CF3, -CF2Cl -CF2CO2R3, where R3 is as defined herein, or -RFȎCF(G)2; or D and E together form a 5-or 6-membered ring whose members are -RF-, where RF is a perfluoroalkylene chain of 4 or 5 members, interruptable by one or two oxygen atoms, and having 0 to 2 substituent -CF3 groups, or G is -F or -CF3.

There is also provided a process for preparing a polyfluoroallyloxy compound which comprises: (1) mixing and reacting a carbonyl compound having the general formula:

wherein A is -F, -COCF3 or -RF where RF is a linear or branched perfluoroalkyl of 1 to 10 carbon atoms, interruptable no more frequently than every second carbon atom by from 1 to 4 oxygen atoms, having 0 to 2 functional groups selected from -SO2F, -SO2OCF2CH3, -COF, -Cl, -OCF2CF=CF2, and -CO2R where R is -CH3 or -C2H5.

B is -F, -CF3, -CF2Cl, CF2CO2R where R has the meaning defined above, or -CF2ORF, where RF is defined above; or A and B together form a 5- or 6- membered ring whose members are -RF- where RF is a perfluoroalkylene chain of 4 or 5 members, interruptable by one or two oxygen atoms, and having 0 to 2 substituent trifluoromethyl groups with a metal fluoride of the formula MF where M is K-, Rb-, Cs-, or R4N- where each -R, alike or different, is alkyl of 1 to 6 carbon atoms; and (2) mixing the mixture from (1) with a polyfluoroallyl compound of the formula: wherein X is -Cl or -F:

W and Z independentely are -F or together are -CF2-, and Y is -Cl or -OCO2F. Preferably W, X and Z are -F and Y is -OSO2F.

Also provided is a copolymer of the aforesaid polyfluoroallyloxy compound with at least one ethylenically unsaturated monomer.

This invention relates to compounds of formula 4 prepared from starting materials 2 and 3 according to the following equation:

In the above equation, starting materials 1, 2, and 3 react to give product 4 and a metal salt 5. The letters A, B, D, E, G, M, W, X, Y and Z are as given above. Products represented by general structure 4 can be converted into useful copolymers especially with tetrafluoroethvlene. trifluoroethylene, vinylidene fluoride, and chlorotrifluoroethylene.

Preferred polyfluoroallyloxy compounds of formula 4 have D and E taken independently with D preferably being -F or RF and E preferably being -F, -CF3, -CF2Cl or CF2CO2R where R is CH3 or -C2H5. The preferred compounds also have W and Z taken independently and X as -F. RF is preferably a linear or branched perfluoroalkyl of 1 to 8 carbon atoms, interruptable with no more than 1 oxygen atom, having 0 or 1 functional group selected from -SO2F, -COF, -Cl, -CO2H, -CO2R , -OCF2CF=CF2 and -OCF2CO2R where R is -CH3 or -C2H5, for example -CF2OCF2COF.

Especially preferred polyfluoroallyloxy compounds of the invention have the formula:

wherein X is -Cl or -F (preferably -F); E is -F, -CF3, -CF2CO2R where R is -CH3 or -C2H5, or -CF2Cl (preferably -F -CF3 or -CF2CO2R3, especially -F) and D is -CF2R4 or

(preferably -CF2R4) where R4is -F, -SO2F, -COF, -CO2H, -CO2R , -OCF2CO2R where R is -CH3 or -C2H5, or -(CF2)xR5 where x is 1 to 6 and R5 is CF3, -COF, -CO2H, -CO2R , -SO2F or -OCF2CF=CF2, preferably R5 is -CF3 or -OCF2CF=CF2.

R4 is preferably -SO2F, -COF, -CO2H or -OCF2CO2R3, where R3 is -CR3 or -C2Rs (especially -SO2F).

The polyfluoroallyl group of the product 4 is derived from the corresponding polyfluoroallyl chloride or fluorosulfate (1) by nucgeophilic displacement of the chloride or fluorosulfate group with a preformed polyfluoroalkoxide anion derived from the metal fluoride (pb5) and the carbonyl compound (53. The synthesis is thus a one-vessel sequential addition of reagents 3 and 1 to a suspension or solution of 2 in a suitable solvent.

Polyfluoroallyl fluorosulfates are the preferred reagents for this dlsplacement, and they can be prepared conveniently by treatment of polyfluoroalkenes with sulfur trioxide, as described in B. E. Smart, J. Org. Chem., 41, 2353 (1976). Such reactions are typically carried out in sealed Carius tubes at temperatures of 25-95"C for periods of 16 hours to 4 days, and the product fluorosulfates are purified by fractional distillation. A preparation of the preferred perfluoroallyl fluorosulfate (pentafluoro-2-propenyl fluorosulfate) is given in Example 2.

Stable metal polyfluoroalkoxides are formed by the reaction of certain metal fluorides with polyfluorinated ketones and acid fluorides (J. A. Young, loc. cit.), thus:

The usefulness of such intermediate polyfluoroalkoxides is determined by their stability, as measured by their ease of thermal decomposition. Because their.formation is reversible, the equilibrium concentrations of various species in a given reaction mixture are important quantities which determine whether or not the subsequent displacement will occur to form product 4. Solutions in which the equilibrium lies towards the right (high concentration of anion) will be more effective than those in which it lies towards the left (high concentration of carbonyl compound).

Polyfluoroalkoxide anion formation and chemistry is dependent upon the following four conditions, discussed in further detail by J. A. Young, loc. cit., F. W. Evans, M. H. Litt, A.

M. Weidler-Kubanek and F. P. Avonda, J. Org. Chem., 33, 1837, 1839 (1968), and M. A.

Redwood and C. J. Willis, Canad. J. Chem., 45, 389 (1967). (1) Stable polytluoroalkoxide anions are formed when the carbonyl compound is highly fluorinated because the electron-withdrawing effect of the fluorine atoms distributes the negative charge over the entire anion. Substitution of some of the fluorine by chlorine, other fluoroalkyl groups or hydrogen destablizes the anion because these groups are less electron-withdrawing and the negative charge is not as readily accommodated. (2) Large cations such as K+, Rb+, Cs+ and R4N+ favor the formation of stable polyfluoroalkoxides more than small cations such as Li+ and Na+ because the lattice energy of metallic fluorides is inversely proportional to cation size. In other words, large cation size and small lattice energy favors disruption of the metallic fluoride crystal structure to form the anion. (3) Solvents which have a high heat of solution for the polyfluoroalkoxide favor its formation. Aprotic polar solvents such as N,N-dimethylformamide (DMF), acetonitrile, and 1,2-dimethoxyethane (glyme) are very effective for this purpose. (4) When there are fluorine atoms alpha to the oxygen atom in the anion, loss of fluoride ion may compete with the desired reactions, e.g.,

has no a-fluorine to lose and forms many stable derivatives.

requires a reactive compound such as allyl bromide for nucleophilic substitution. usually eliminates F-; nucleophilic substitution is known with perfluoroallyl fluorosulfate.

In the practice of this invention, the polyfluoroalkoxide anion is preferably preformed by the addition of the carbonyl compound to a stirred mixture of the metal fluoride in a suitable aprotic solvent. The completeness of formation of the anion is generally signalled by the extent to which the metal fluoride dissolves in the solvent as the reaction progresses.

The stoichiometry of polyfluoroalkoxide anion formation requires one molar equivalent of metal fluoride for each carbonyl group which is converted to its anion, e.g.:

The presence of up to a twice-molar excess of metal fluoride is generally not detrimental.

Two side effects of excess metal fluoride are: (1) to hinder the observation of the reaction endpoint because of the presence of undissolved solid in the reaction mixture, and (2) excess fluoride ion in solution may react directly with perfluoroallyl fluorosulfate to form hexafluoropropene.

Because of the limited thermal stability of polyfluoroalkoxides, their formation is usually accomplished between -20"C and +60"C, preferably with external cooling to maintain the temperature between 0 C and 10 C.

The time required to complete polyfluoroalkoxide formation varies with the carbonyl component, but it is preferably from 0.5 to 2 hours, each individual case being usually determined by how long it takes the reaction mixture to become homogeneous.

N,N-Dimethylformamide (DMF), acetonitrile, N,N-dimethylacetamide (DMAC), butyrolactone, 1 ,2-dimethoxyethane (glyme), 1-(2-methoxyethoxy)-2-methoxyethane (diglyme), 2,5,8,1 1-tetraoxadodecane (triglyme), dioxane, sulfolane, nitrobenzene and benzo nitrile are suitable, illustrative aprotic polar solvents for the preparation of polyfluoroalkoxides and their subsequent reaction with the polyfluoroallyl chloride or fluorosulfate. DMF, diglyme, triglyme and acetonitrile are preferred solvents for these reactions.

The apparatus, reactants and solvents should be adequately dried for use in the process of the invention because the presence of water hydrolyzes polyfluoroalkoxides:

Metal fluorides which are useful in this invention are potassium fluoride (KF), rubidium fluoride (RbF), cesium fluoride (CsF) and tetraalkylammonium fluorides (R4NF) such as tetraethylammonium fluoride ((CoHs)4NF) and tetrabutylammonium fluoride ((C,H9)4NF). R, alike or different, is alkyl of 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms. Potassium fluoride is preferred because of its availability, economic advantage, and ease of handling.

Polyfluorinated carbonyl compounds which are useful in this invention are ketones and carboxylic acid fluorides and a perfluorinated lactone 3,6.bis(trifluoromethyl)3,5,5,6- tetrafluoro-1,4-dioxan-2-one. Ketones and the lactone give branched fluorocarbon products, whereas acid fluorides give primary fluorocarbon products in which the new ether linkage is at the primary or secondary center:

( RF) 2C ) ( RF) 2Cl-O-CF2CF'Cr2 (,tn') Th Rr=c Rr Hzcoccp.cr2 (lxrz rX RFCOF W RFCFzOCF2CF"CF2 (cid Iluorldn) Polyfluorinated ketones which are useful include hexafluoroacetone, chloropentafluoroacetone, 1,3-dichlorotetrafluoroacetone, l,1-difluoroethyl 2oxopentafluoropropanesulfonate, dimethyltetrafluoroacetone- 1 3-dicarboxylate, 1,3-bis(2heptafluoropropoxy) tetrafluoropropanone, octafluorobutanone, decafluoro-2-pentanone, dodecalfluoro-2-hexanone, tetradecafluoro-2-heptanone, hexadecafluoro-2-octanone, octadecafluoro-2-nonanone, eicosafluoro-2-decanone, and hexafluoro-2,3-butanedione.

Hexafluoro-2,3-butanedione is a special case (Example 12) in that the initially formed perfluoroalkoxide reacts both with perfluoroallyl fluorosulfate and with another molar equivalent of hexafluoro-2,3-butanedione to form a mixture of two heterocyclic compounds.

Polyfluorinated acid fluorides which are useful include carbonyl fluoride, trifluoroacetyl fluoride, pentafluoropropionyl fluoride, heptafluorobutyroyl fluoride, nonafluoropentanoyl fluoride, tetrafluorodiglycolyl difluoride

undecafluorohexanoyl fluoride, tridecafluoroheptanoyl fluoride, pentadecafluorooctanoyl fluoride, heptadecafluorononanoyl fluoride, nonadecafluorodecanoyl fluoride, difluoromalonyl difluoride, tetrafluorosuccinyl difluoride, hexafluoropropane- 1 ,3-dioyl difluoride (hexafluoroglutaryl difluoride), octafluorobutane- 1 ,4-dioyl difluoride (octafluoroadipoyl difluoride), decafluoropentane-1,5-dioyl difluoride (decafluoropimelyl difluoride), dode cafluorohexane-l,6-dioyl difluoride (dodecafluorosuberyl difluoride), fluorosulfonyldifluoroacetyl fluoride, 2-(fluorosulfonyl)tetrafluoropropionyl fluoride, 2-(1heptafluoropropoxy)-tetrafluoropropionyl fluoride, 2-[2-( 1-heptafluoropropoxy) hexaf luoropropoxy]tetrafluoropropionyl fluoride, and 2-{2-[2-(1 heptafluoropropoxy)hexafluoropropoxy] hexafluoropropoxy}tetrafluoropropionyl fluoride, carbomethoxydifluoroacetyl fluoride.

The ketone 1, 1-difluoroethyl 2-oxopentafluoropropanesulfonate (Example 3) is a special case as a starting material because it is an in situ source of 2-oxopentafluoropropanesulfonyl fluoride since the latter has not been isolated.

Many of the above starting materials are commercially available, e.g. PCR, Gainesville, Florida is a supplier of fluorinated ketones and carboxylic acids. Examples 2, 3, 4, 5, 7, 9, 10. 11, 12, 13, 16 and 19 give sources and methods of preparation of some compounds which are not commercially available. Generally, perfluoroketones can be prepared from the esters of perfluoroalkanecarboxvlic acids and from the reaction of carbonyl fluoride with perfluoroalkenes (W. A. Shepp:drd and C. M. Sharts, "Organic Fluorine Chemistry", p.

365-368, W. A. Benjamin, New York, 1969, H. P. Braendlin and E. T. McBee, Advances in Fluorine ChemisQv, 3, 1 (1963)). Perfluoroalkanecarboxylic acid fluorides and pertruoroalkane-a.o-dicarboxylic acid difluorides are prepared by treatment of the corresponding acids with sulfur tetrafluoride, by the addition of carbonyl fluoride to perfluoroalkenes (F. S. Fawcett C. W. Tullock and D. D. Coffman, J. Amer. Chem. Soc., 84 4275. 4285 (1962)) and by electrolysis of alkanecarboxylic acids in hydrogen fluoride (M.

Hudlicky. Chemistry of Fluorine Compounds", p. 86, MacMillan Co., New York, 1962).

Perfluoroalkanedicarboxylic acids are prepared by oxidation of fluorinated a.co-dialkenes or fluorinated cycloalkenes (Hudlicky, loc. cit., p. 150-152). Perfluoroalkyl polyethers with a terminal acid fluoride group can be made from hexafluoropropene oxide and its fluoride ion induced oligomers, as described by R. A. Darby, U.S. Patent 3,450,684 (1969) and by P. Tarrant, C. G. Allison, K. P. Barthold and E. C. Stump, Jr., Fluorine Chem. Rev., S, 88 (1971).

The stoichiometry of the displacement with polyfluoroallyl chloride or fluorosulfate requires one molar equivalent of this reagent for each reactive center in the polyfluoroalkoxide anion. With a difunctional polyfluoroalkoxide, however, the stoichiometry can be adjusted to give either the mono- or the di-substitution product, thus:

(Example 5)

(Example 17) FCO(CF2)4COF + KF + CF2 = CFCF2OSO2F < CF2 = CFCF2O(CF2)sCOF (Examples 21, 22) FCO(CF2)4COF + 2KF + 2CF2 = CFCF2OSO2 F < (CF2=CFCF2OCF2CF2CF2)2 (Example 13) The formation of the polyfluoroalkoxide and its subsequent reaction with the polyfluoroallyl chloride or fluorosulfate can be carried out sequentially without isolation of intermediates in glass apparatus at atmospheric pressure using the normal precautions to exclude moisture. The use of cooling baths and low temperature condensers (e.g. those packed with dry ice and acetone mixtures) serves to moderate the reactions and facilitate the retention of volatile reagents and products. The progress of the displacement reaction is conveniently followed bv the appearance of a precipitate of the salt MY O, by gas liquid partition chromatography (glpc) and by fluorine nuclear magnetic resonance spectroscopy ("F NMR).

The displacement reaction can be carried out between -200C and +80"C, and is preferably between 0 C and 30"C. Typically, the reaction mixture is cooled externally to 0 C to 150C during the addition of the polyfluoroallyl choride or fluorosulfate, and is then allowed to warm up to 25"C to 30"C for the remainder of the reaction time.

The time required to complete the displacement reaction varies from one to 24 hours, and is preferably from 2 to 4 hours. Typically, the reaction mixture is externally cooled for 5 to 45 min while the polyfluoroallyl chloride or fluorosulfate is being added, and is then stirred at room temperature for 2 to 3 hours.

The products of the reaction are isolated by standard procedures. In some cases, the reaction product is appreciably more volatile than the high-boiling solvent used (diglyme bp 162"C. DMF bp 153"C) and can be distilled into a trap cooled to -800C by warming the reaction vessel to 30"C to 500C under a reduced pressure of 1 to 200 mm of Hg.

Alternativelv. the reaction mixture can be poured into five to ten times its volume of water; the insoluble lower layer of fluorinated product is separated, washed free of solvent with more water dried and fractionally distilled from phosphorus pentoxide or concentrated sulfuric acid.

The polyfluoroallyloxy compounds of this invention are unsaturated monomers which can be converted to new and useful polymers. Polyfluoroallyloxy monomers can be homopolymerized under high pressure to oligomeric compositions of matter. The economic factors of a costly monomer and the necessity for high pressure operation, however, make it preferable to incorporate these monomers into copolymers formed with less expensive ethylenically unsaturated monomers, e.g., olefins such as ethylene or propylene; halogenated olefins such as tetrafluoroethylene, trifluoroethylene, hexafluoropropylene, vinylidene fluoride, vinylidene chloride, trifluoromethyl trifluorovinyl ether and chlorotrifluoroethylene; and acrylic acid or methacrylic acid esters. Halogenated olefins are preferred, especially tetrafluoroethylene, chlorotrifluoroethylene, trifluoromethyl trifluorovinyl ether, hexafluoropropylene and vinylidene fluoride. Such copolymers have either more desirable or entirely new properties not possessed by e.g. poly(tetrafluoroethylene), poly(trifluoroethylene), poly(vinylidene fluoride), poly(chlorotrifluoroethylene) or polyethylene. Copolymerization may be defined as any process whereby two or more monomers are incorporated as integral parts of a high polymer. A copolymer is the product resulting from such a process. It is not necessary that the relative numbers of the different types of unit be the same in different molecules of the copolymer or even in different portions of a single molecule.

Copolymers which contain from about 5-55 weight percent (about 1-25 mole percent) of polyfluoroallyloxy comonomer have lower melting points than the corresponding polyfluoroolefins, and consequently are more readily molded and shaped into useful objects.

Copolymers which contain from about 0.1-10 weight percent, preferably about 1-10 percent (about 0.3-5 mole percent) of a polyfluoroallyloxy comonomer with pendant SO2F or COF groups can be partially hydrolyzed to a copolymer bearing SO2OR or CO2H groups which have an affinity for cationic dye molecules. Thus, it is possible to dye fluorocarbon polymers in a variety of colors. This cannot be done with polyfluoroolefins which do not have incorporated comonomer of this type. Copolymers which contain from about 5 to 35 weight percent (about 1.0 to 10 mole percent) of a polyfluoroallyloxy conomomer with pendant SO2F or COF groups can also be partially or essentially completely hydrolyzed to a copolymer bearing hydrophilic SO2Ofl and CO2H groups. Such a copolymer has an affinity for water and is water-wettable. Polyfluoroolefins which do not have incorporated a comonomer of this type are not wetted and are impermeable to water. A second important feature of copolymers which contain about 1.0 to 10 mole percent of a polyfluoroallyloxy comonomer bearing -SO2OR or -CO2H groups or ionized forms thereof; e.g.

-SO?O-Na or CO-Nat. is their capacity for ion exchange. A specific use for such polymers is in a chloroalkali cell, such as disclosed in German patent application 2,251,660, published April 26, 1973, and Netherlands patent application 72.17598, published June 29, 1973. wherein an ion-exchange polymer in the form of a film membrane or diaphragm is used to separate the anode and cathode portion of the cell from which chlorine and sodium hydroxide are respectively produced from brine flowing within the anode portion of the cell.

The properties of each copolymer depend upon the distribution of monomer units along the polymer chain since a copolymer is not a physical mixture of two or more polymers each derived from the respective monomers but a new material incorporating each monomer. It is well known that the composition of such a copolymer may also be quite different from that of the monomer mixture (feed) from which it is formed. Furthermore, "the relative tendencies of monomers to be incorporated into polymer chains do not correspond at all to their relative rates of polymerization alone....the reactive properties of a growing polymer chain depend primarily upon the monomer unit at the growing end, and not upon the length and composition of the chain as a whole.", C. Walling, "Free Radicals In Solution", pages 99-100, John Wiley & Sons, Inc., New York (1957).

The copolymerization reaction to prepare the present copolymers can be carried out either in a nonaqueous or an aqueous medium with the reactants and initiator in solution, suspension, or emulsion form in a closed vessel with agitation. This type of reaction is well known to those skilled in the art.

The copolymerization is initiated by a free radical type initiator which is generally present at a concentration of from 0.001 to 5 percent by weight of the reaction mixture, and is preferably from 0.01 to 1.0 percent by weight. Such free radical initiator systems are preferably operable at or below 25"C, and are exemplified by, but not restricted to pentafluoropropionyl peroxide (C2F5COO)2, dinitrogen difluoride (N2F2), azobisisobutyronitrile, ultraviolet irradiation and ammonium or potassium persulfate; mixture of iron (II) sulfate with hydrogen peroxide, ammonium or potassium persulfate, cumene hydroperoxide, t-butyl hydroperoxide; mixtures of silver nitrate and ammonium or potassium persulfate; mixtures of trifluoroacetic acid, pentafluoropropionic acid, heptafluorobutyric acid or pentadecafluorooctanoic acid with ammonium or potassium persulfate.

The peroxide systems may contain additionally sodium sulfite, sodium metabisulfite, or sodium thiosulfate.

When aqueous emulsion systems are used for copolymerization they contain emulsifying agents in the form of the sodium or potassium salts ot saturated aliphatic acids of between about 14 and 20 carbon atoms or of perfluoroalkanoic acids and perfluoroalkanesulfonic acids of between 6 and 20 carbon atoms, e.g., potassium stearate or potassium pentadecafluorooctanoate. These emulsifiers may constitute between 0.1 nd 10.0 weight percent of the reaction mixture and preferably constitute between 0.5 and 5 parts by weight percent.

Aqueous emulsion systems are customarily buffered to pH 7 or above by the addition of reagents such as disodium hydrogen phosphate, sodium metaborate, or ammonium metaborate to the amount of about 1 to 4 weight percent of the reaction mixture.

The following three types of copolymerization systems are preferred in preparing the preferred copolymers of this invention: 1) Solutions of two or more comonomers in 1,1,2-trichloro-1,2,2-trifluoroethane (FreonR 113) solvent containing pentafluoropropionyl peroxide are shaken in an autoclave at about 25 C for about 20 hours. The crude polymer is isolated by evaporation of the solvent and freed from monomers and lower oligomers by washing with more solvent.

2) An aqueous emulsion of two or more comonomers containing an emulsifier such as potassium perfluorooctanesulfonate and an initiator such as ammonium persulfate is ID=9.1 A mixture of commercial liquid sulfur trioxide (10 ml) and hexafluoropropene (45 g 0.30 mol) was sealed in a Carius tube at liquid nitrogen temperature, mixed well at 250C, allowed to stand for 4 days at 25 C. and finally heated in a steam bath for 6 hours. From two such tubes, there was obtained by distillation, 3-(trifluoromethyl)-3,4,4-trifluoro-1-oxa-2thiacyclobutane 2,2-dioxide (2-hydroxy-1-trifluoromethyl- 1 ,2,2-trifluoroethane sulfonic acid sultone, D. C. England, M.A. Dietrich and R.V. Lindsey, Jr.,J. Amer. Chem. Soc., 826181 (1960)) (25 g, 22%) bp 44 C, and pentafluoro-2-propenyl fluorosulfate (hereinafter refcrred to as perfluoroallyl fluorosulfate) (73 g 63%), bp 58-60 C. l'crfluoroallyl fluorosulfate is characterized by: #max 5.55 (C=C) and 6.75 ,um (SO2); l"F NMR, 46.1 (t J = 8.5 Hz, each member d J = 1.8 Hz) 1F, SO2F, -74.0 (d J = 28.2 Hz, each member d J = 13.9 Hz, d J = 8.5 Hz, d J = 7.8 Hz) 2F, -91.2 (d J = 50 Hz, each member d J = 40.5 Hz, t J = 7.8 Hz) 1F, -104.7 (d J = 119.4 Hz, each member d J = 50 Hz, d J = 2X.2 Hz) IF, and -192.4 ppm (d J = 119.4Hz, each member d J = 40.5 Hz, t J = 13.9 Hz, d J = 1.8 Hz) 1F.

B. 1-(1,1,1,2,3,3-Hexafluoro-3-chloro-2-propoxy)-pentafluoro-2-propene

A suspension of potassium fluoride (5.80 g, 0.10 mol) and diglyme (100 ml) was stirred at 20 C in a cooling bath while chloropentafluoroacetone (18.3 g, 0.10 mol) was distilled in.

After the potassium fluoride had dissolved, perfluoroallyl fluorosulfate (23.0 g, 0.10 mol) was added rapidly with cooling of the reaction mixture. The resulting exothermic reaction was accompanied by the precipitation of solid. The mixture was stirred at 25 C for one hour, and then the volatile components were transferred to a trap cooled to -800C by heating the reaction mixture at 42 C (5 mm Hg). The volatile product was distilled from phosphorus pentoxide to give 1-(1,1,1,2,3,3-hexafluoro-3-chloro-2-propoxy)-pentafluoro- 2-propene, (19.6 g, 0.059 mol, 59%) bp 85-86 C which was characterized by: #max 5.55 (CF = CF2) and 7-lí) m (CF, C-O); 1@F NMR, -68.6(m) 2F, CF2Cl, -69.1 (m) 2F, CF2O, -78.8 (m) 3F. CF3, -93.2 (d J = 54.7 Hz, each member d J = 39.8 Hz, t J = 7.5. Hz), 1F, cis-CF2-CF=CF, - 105.9 (d J = 116.7 Hz, each member, d j = 54.7 Hz, t J = 24.0 Hz) IF, trans-CF2-CF=CF, -141.2 (t J = 22.8 Hz, each member m) 1F, CF, and -190.4 ppm (d J = 116.7 Hz. each member d J = 39.8 Hz, t J = 13.4 Hz) IF, -CFCF=C.

Anal. Calcd for C6ClF11O: C, 21.67; Cl, 10.66 Found: C, 21.34; Cl, 10.21 EXAMPLE 3 2-(1-Pentafluoro-2-propenyloxy)hexafluoropropane-1-sulfonyl fluoride (2 Perfluoroallyloxypropane-1-sulfonyl fluoride)

(i) Dropwise addition of sulfur trioxide (12.8 g, 0.16 mol) to 2-ethoxy-1,1,3,3,3pentafluoropropene (D. W. Wiley and H. E. Simmons, J. Org. Chem., 29, 1876 (1964)) (29.0 g, 0.165 mol) produced an exothermic reaction. The black reaction mixture was distilled to give recovered 2-ethoxy-1,1,3,3,3-pentafluoropropene (6.3 g, 0.036 mol, 22%, identified by ir) and ethyl 2-oxopentafluoropropanesulfonate (20.2 g, 0.078 mol, 49% conversion and 63% yield) bp 47-48 C (12 mm Hg): #max 3.34 and 3.41 ( saturated CH), 5.60 (C = O), 7.09 (SO2O), and 7.6-8.5 m (C-F, SO2); IH NMR, # 4.59 (q J = 7.2 Hz) 2H, OCH2 and 1.51 ppm (t J = 7.2 Hz) 3H, CH3; 19F NMR, -75.0 (t J = 8.3 Hz) 3F, CF3, and -107.4 ppm (q J = 8.3 Hz) 2F, CF2.

(ii) The above reaction was repeated at 0-5 C with sulfur trioxide (88 g, 1.1 mol) and 2-ethoxy-1,1,3,3,3-pentafluoropropene (176 g, 1.0 mol). The colorless reaction mixture, which darkened on standing overnight, was distilled to give recovered 2-ethoxy-1,1,3,3,3pentafluoropropene (28.6 g, 0.16 mol, 16%) bp 46-48 C, ethyl 2oxopentafluoropropanesulfonate (145.1 g, 0.57 mol 57% conversion and 68% yield) bp 48-52 C (1 mm Hg), and a higher boiling fraction composed mainly of 2oxopentafluoropropanesulfonic acid. The crude acid was redistilled at 81-82 C (6.2 mm Hg), yield 35.6 g (0.16 mol, 16% conversion and 19% yield) of pure acid: #max (CCl4, CaF2 plates) 3.3 and 4.2 (broad) (SOH), 5.58 (C=O), 7.13 (SO2O) and 7.5 - 9 m (CF, SO2); 1H NMR # 10.2 ppm (s) SO2OH; 19F NMR, -76.2 (t J = 7.5 Hz) 3F, CF3, and -108 ppm (q J = 7.5 Hz) 2F,CF2).

Anal. Calcd for C3HF5O4S: C, 15.80; H, 0.44: F, 41.65; S, 14.06 Found: C, 15.95; H, 0.55; F, 41.55; S, 13.89 (iii) Ethyl 2-oxopentafluoropropanesulfonate (25.6 g, 0.10 mol) was stirred at 25 C and trated with trifluoroacetic acid (17.2 g, 0.15 mol). The mixture was allowed to stand overnight, and then it was heated to reflux (60 C) in a spinning band still. Fractional distillation of the mixture at a pot temperature below 100 C gave 2oxopentafluoropropanesulfonic acid (18.4 g, 0.81 mol, 81%) bp 73 C (2.5 mm Hg).

B. 1,1-Difluoroethyl 2-oxopentafluoropropanesulfonate

A metal tube containing 2-oxopentafluoropropanesulfonic acid (23.8 g, 0.10 mol) was cooled below -40 C and vinylidene fluoride (1,1-difluoroethane) (13 g, 0.20 mol) was added. The mixture was shaken and warmed to 250C where it was kept for 4 hours.

Distillation of the liquid product gave 20.4 g (0.07 mol, 70%) of 1,1-difluoroethyl 2-oxopentafluoropropanesulfonate, bp 62-63 C (50 mm Hg): #max (CCl4) 5.54 (C=O), 6.96 (SO2O) and 7.5-9 m (CF, SO2); 1H NMR, # 2.06 ppm (t J = 14.3 Hz) CH3; 19F NMR, 58.3 (q J = 14.3 Hz, each member t J = 7.1 HZ) 2F, OCF2, - 75.0 (t J = 8.0 Hz) 3F, CF3 and -106.1 ppm (q J = 8.0 Hz, each member t J = 7.1 Hz) 2F, CF2SO2.

Anal. Calcd for C5H3F7O4S: C, 20.56; H, 1.03; F, 45.52 Found. C, 20.73; H, 1.03; F, 45.72 A similar experiment on a 0.8-mol scale gave an 86% yield of product bp 60 C (50 mm Hg). This material was stored in polytetrafluoroethylene bottles to avoid degradation.

C. 2- (1 Pentafluoro-2-pmpenyloxy)hexafluornprnpane4-sulfonyl fluoride

A suspension of sdry potassium fluoride (5.80 g; 0.10 mol) in 2, 5, 8, 11-tetraoxadodecane (triglyme) (100 ml) was stirred and cooled at 0 C while 1,1-difluoroehtyl 2oxopentafluoropropanesulfonate prepared as in Example 3B (29.2 g, 0.10 mol) was added.

When the potassium fluoride had nearly all dissolved, perfluoroallyl fluorosulfate prepared as in Example 2A (23.0 g, 0.10 mol) was added at 0 C, and the resulting mixture was stirred at 20-26 C for 3 hours. Volatile components were removed by distillation at a flask temperature of 25 C and 1 mm Hg pressure. The distillate was washed with cold dilute ammonium hydroxyde, dried and distilled togive 2-(a1-pentafluoro-2propenyloxy)hexafluoropropane-1-sulfonyl fluoride (13.0 g, 0.034 mol, 34%), bp 47-48 C (60 mm Hg) whose structure was confirmed by: #max 5.59 (CF=CF2), 6.80 (SO2F) and 7.510 m (C-F, C-O, SO2); 19F NMR, + 45.4 (m) 1F, SO2F, -70.0 (m) 2F, OCF2, -78.0 (quintet J = 10.7 Hz) 3F, CF3, -91.5 (d J = 51.5 Hz, each member d J = 39.5 Hz, t J = 7.5 Hz) 1F, cis-CF2CF = CF, -104.8 (d J = 117.0 Hz, each member d J = 51.5 Hz, t J = 25.5 Hz) 1F, trans-CF2CF = CF, -107.0 nd -108.4 (AB J = 255 Hz, each member q J = 10.7 Hz. m) 2F, CF2SSO2F, -138.7 (t J = 20.2 Hz, each member m) 1F, CF, and -190.8 ppm (d J = 117.0 Hz, each member d J = 39.5 Hz, t J = 13.0 Hz) 1F, CF2CF=C.

Anal. Calcd for C6F1203S: C, 18.96; F, 59.98; S, 8.43 Found: C, 19.24; F, 60.06; S, 8.26 In a similar reaction to Example 3C, it was shown by ir that the gases generated were composed mainly of acetyl fluoride and small amounts of hexafluoropropene and sulfuryl fluoride.

EXAMPLE 4 1-{1,3-bis(2-Heptafluoropropoxy)-2-pentafluoropropoxy)-pentafluoro-2-propene A. 1,3-bis(2-Heptafluoropropoxy)tetrafluoropropanone

A mixture of dry potassium fluoride (21.0 g, 0.36 mol), dry N,N-dimethylformamide (DMF) (150 ml), hexafluoroacetone (59.8 g, 0.36 mol) and l,3-dichlorotetrafluoroacetone (35.8 g, 0.18 mol) was heated at reflux (40-60 C) for 3 days. Distillation into a trap cooled to -80 C gave recovered hexafluoroacetone (16.5 ml, 46%) and a 63 g of liquid bp 30-1458C.

The higher-boiling material was redistilled from sulfuric acid to give 1,3-bis(2heptafluoropropoxy)tetrafluoropropanone (18.7 g, 0.037 mol, 21% conversion, 39% yield based on hexafluoroacetone), bp 117-118 C; #max (CCl4) 5.51 (C=O) and 7.5-9 m (CF, C-O-C); MS m/e 479 (M-F)+, 313 (M-F-CF3COCF3)+, 263 (M-F-CF3COCF3-CF2)+, 235 [(CF3)2CFOCF2]+, 169 (C3F7)+, 147 (CF3COCF2)+, 97 (CF3CO)+ and 60 (CF3)+; 19F NMR, -75.0 (d J = 21.5 Hz, each member septet J = 5.5 Hz) 2F, OCF2, -81.4 (m) 6F, CF3, and -145.3 ppm (t J = 21.5 Hz, each member septet J = 2.1 Hz) 1F, CF.

Anal. Calcd for C9F18O3: C, 21.70; F, 68.66 Found: C, 21.60; F, 68.59 B. 1-{1,3-bis(2-Heptafluoropropoxy)-2-pentafluoropropoxy}-pentafluoro-2-propene

A mixture of 1,3-bis(2-heptafluropropoxy)tetrafluoropropanone (20.0 g, 0.04 mol), diglyme (100 ml) and potassium fluoride (2.32 g, 0.04 mol) was stirred an warmed to 55 C.

The two liquid phases and solid originally present became homogeneous and stayed so upon cooling. Perfluoroallyl fluorosulfate prepared as in Example 2A (10.0 g, 0.043 mol) was added rapidly at 10 C and the mixture was allowed to warm. The slight exothermic reaction was accompanied by precipitation of solid and the appearance of a second liquid phase. The mixture was stirred for 2 hours and then poured into water (350 ml). The lower layer was washed with water (75 ml), dried over phosphorus pentoxide and distilled to give 1-{1,3-bis)2-heptafluoropropoxy(-2-pentafloropropoxy}-pentafluoro-2-propene ( 16.1 g, 0.024 mol, 62% ) bp 64-67 C (25 mm Hg) whose structure was confirmed by: #max 5.57 (CF2 = CF) and 7.5-9 m (CF, C-O); 19F NMR, -69.4 (m) 2F, OCF2C=C; -80.3 (broad) 4F, CFOCF2 -81.5 (s) 12F, CF3, -93.7 (d J = 54.0 Hz, each member d J = 39.6 Hz, t J = 7.8 Hz) 1F, cis-CF2 - CF = CF, -106.3 (d J = 117.4 Hz, each member d J = 54.0 Hz, t J = 23.7 Hz) 1F, trans-CF2CF = CF, -145.8 (m) 3F, OCF, and -190.9 ppm (d J = 117.4 Hz, each member d J = 39.6 Hz, t J = 16.6 Hz) 1F, CF,CF = C.

Anal. Calcd for C12F2403: C, 22.24; F, 70.35 Found: C, 22.66; F, 70.27 EXAMPLE 5 3- (I -Pentafluoro-2-pvopenyloxy) tetrafluoropropiony1 fluoride A. Difluoromalonyl difluoride

3-Methoxytetrafluoropropionyl fluoride (F. S. Fawcett, C.W. Tullock and D. D.

Coffman, J. Amer. Chem. Soc., 84, 4275 (1962) (81 g, 0.45 mol) was slowly added to sulfur trioxide (80 g, 1.0 mol) at 40 C, and the product difluoromalonyl difluoride, bp -9 C, was continuously removed by distillation through a low temperature still, yield 58 g (0.40 mol, 90%). The product structure was confirmed by: #max 1860 cm-1 (COF), 19F NMR (no solvent) +17.1 ppm (t J = l() Hz) 2F, COF and -114.2 ppm (t J = 10 Hz) 2F, CF2.

B. 3-(1-Pentafluoro-2-propenyloxy)tetrafluoropropionyl fluoride

A mixture of dry potassium fluoride (7.5 g, 0.13 mol) and diglyme (100 ml) was stirred at 1() C and difluoromalonyl difluoride from part A (18.5 g, 0.13 mol) was distilled into it.

After 2() min. the potassium fluoride was nearly all dissolved, and perfluoroallyl fluorosulfate prepared as in Example 2A (29.9 g, 0.13 mol) was added dropwise at 10-15 C.

The mixture was stirred for 3 hours, then the volatile components were removed at a pot temperature of 32 C and 4.X mm Hg pressure. Fractionation of the distillate gave 3-( 1-pentafluoro-2-propenyloxy)tetrafluoropropionyl fluoride (14.9 g, 0.051 mol, 39%) bp 70-71 C and a small amount of higher bp material. The product structure was confirmed by: #max 5.33 (COF). 5.6() (CF = CF2) and 7.5-10 um (CF2C-O); 19F NMR 23.7 (apparent quintet. J ~ 7.5 Hz) 1F. COF, -71.9 (d J = 24.6Hz, each member t J = 13.9 Hz, d J = 13.9 Hz. d J = 7.4 Hz) 2F, OCF2C=C, -86.7 (m) 2F, CF2O, -91.6 (d J = 51.8 Hz, each member d J = 39.4 Hz. t J = 7.4 Hz) 1F. cis-CF2CF = CF, -105.1 (d J = 117.1 Hz, each member d J=51.8 Hz. t J = 24.6 Hz) 1F. trans-CF2-CF=CF, -122.0 (d J = 8.2 Hz, each member t J = 3.1 Hz) 2F, FCOCF2, and -191.0 ppm (d, J = 117.1 Hz, each member d, J = 39.4 Hz. t J = 13.9 Hz, t J = 1.6 Hz) 1F, CF2-CF=C.

Anal. Calcd for C6F10O2: C, 24.51 Found: C, 24.56 EXAMPLE 6 Perfluoro-3,6-dioxanon-8-enoyl fluoride A. Tetrafluorodigylcolyl chloride

A mixture of 307.6 g (1.46 mol) of dichlorotetrafluorodihydrofuran, 157.8 g(3.9 mol) of NaOH. 312 g (1.97 mol) of potassium permanganate and 1500 ml of water was refluxed for 17 hours. A brief (steam) distillation gave 10.6 g (3%) of recovered dihydrofuran. The reaction mixture was filtered and the filter cake triturated with 2 x 400 ml of water. The combined aqueous solutions were evaporated to 1500 ml, treated cold with 300 ml of conc.

H2SO4 and extracted continuously with ether for a day. The extracts were evaporated until ether was no longer evolved et 25 C (0.5 mm Hg). To the crude solid diacid, 279 g (up to 93% yield), was added 5 g (0.06 mol of pyridine and 416.5 g (3.5 mol) of thionyl chloride.

Little gas evolution occurred at this stage, but considerable gas evolved as the mixture was stirred and warmed past 40 C. Evolved gases were passed through a 0 trap; after 4 hours at ca. 40 C. gassing slowed and trap contents (10 ml) were returned to the pot. The mixture was then refluxed, with occasional return of cold trap contents to the reaction, until the head temperature reched 81 C and no gas was being evolved. Fractionation afforded 215.2g (61% from dihvdrofuran) of tetrafluorodigylcolyl chloride, bp 94-97 C. Structure was confirmed bv NM'R: 19F -77.0 ppm (s, -CF2O-).

Tetrafluorodigylcolyl chloride, bp 96.50C, has previously been prepared by a different route by R. E. Banks, E. D. Burling, B. A. Dodd, and K. Mullen, J. Chem. Soc. (C).

1706 (1969).

B. Tetrafluorodiglycolyl Fluoride

Conversion of the diacid chloride to the corresponding fluoride, bp 32-33 C was accomplished by a scale-up of the procedure of R. E. Banks, E. D. Burling, B. A. Dodd. and K. Mullen, J. Chem. Soc. (c), 1706 (1969). A mixture of 215 g (0.885 mol) of tetrafluorodiglycolyl dichloride. 140.5 g (3.35 mol) of NaF, and 1200 ml of anhvdrous acetonitrile was stirred overnight, then distilled to give a fraction collected at 35-79 C. The distillate was treated with 20 g of NaF and distilled to give 105 g of tetrafluorodiglvcolyl difluoride, bp 32.33 C. Addition of another 100 g (2.38 mol) of NaF to the reaction mixture and slow distillation afforded another fraction. bp 35-81 C. Treatment with 10 g of NaF and fractionation gave another 37.() g of difluoride product, bp 32-33 C, for a total of 142 g (76%).

C. Perfluoro-3, 6-dioxanon-8-enoyl Fluoride

A mixture of 38.9 g (0.67 mol) of KF, 141.5 g (0.67 mol) of tetrafluorodiglycolyl difluoride, and 500 ml of dry diglyme was stirred for 30 minutes at 5"C. during which time nearly all of the KF dissolved. Then 154.1 g (0.67 mole) of perfluoroallyl fluorosulfate was added rapidly at 5 C and the mixture was stirred at 0-50C for 3 hours, at 25 C for 2 hours, and allowed to stand overnight. Volatiles were evaporated to diglyme reflux at 38 C (3 mm Hg). Distillation of volatiles from 20 g of NaF gave 28.2 g (20%), of recovered diacid fluoride, bp 32-33 C, and 125.0 g (52%) of monoacid fluoride, almost all of it bp 93-94SC.

Structure was confirmed by: ir (CCI4): 5.30 (COF). 5.59 (C=C). 8-9 @ (CF, C-O). NMR: F 13.3 (m. 1 F. COF), -72.0 (d of d oft of d, JFF 25. 13, 13. 7.7 Hz. 2F.

=CFCF2), -77.5 (t of d. JFF 11.5, 2.7 Hz, 2 F. CF2CO2F), -88.8 (t. JFF 11.5 Hz. 2 F.

CF2OCF2COF), -89.4 (t. JFF 12.7 Hz. 2 F, =CFCF2OCF2) -91.9 (d of d of t. JFF 52.7.

39.3. 7.7 Hz, 1F. cis-CF2CF=CF). -105.3 (d of d of t, JFF 117.6, 52.7. 24.6 Hz. 1 F, trans-CF2CF=CF), and -190.8 ppm (d of d of t of t. JFF 117.6. 39.3. 13.7. 1.6 Hz. 1 F, CF2CF=), EXAMPLE 7 2-(1-Pentafluoro-2-propenyloxy)tetrafluoroethanesulfonyl fluoride

A suspension of potassium fluoride (5.8 g. 0.10 mol) in diglyme (100 ml) was stirred and cooled while fluorosulfonyldifluoroacetvl fluoride (18.0 g. 0.10 mol) (D.C. England, M.A.

Dietrich and R. V. Lindsey. Jr.. J. Amen: Chem. Soc., 82 6181 (1960) was added rapidly.

The mixture was stirred for 15 min at 20-30 C during which time the potassium fluoride dissolved. and then it was treated with perfluoroallyl fluorosulfate prepared as in Example 2A (25.0 g 0.11 mol) at 20-25 C over 5 min. The mixture was stirred for 2 hours, during which time solid precipitated. and the temperature rose to 28 C and fell again. The volatile components were transferred to a trap cooled to - 80 C by warming the solution to reflux at 38 C (t mm Hg). The distillate was treated with concentrated sulfuric acid (10 ml) to remove diglyme . then distilled to give 2-(1-pentafluoro-2 propenyloxy)tetrafluoroethanesulfonyl fluoride (19.9 g, 0.06 mol, 60%) bp 55-56 C (150 mm Hg). The product structure was confirmed by: #max 5.53 (CF2=CF), 6.79 (SO2F) and 7-10 m (CF,C-O,SO2); 19F NMR, +44.9 (t J = 6 Hz, each member t J = 6 Hz) 1F, FSO2, -71.8 (d J = 25.3 Hz, each amember t J = 113.8 Hz, d J = 13.8 Hz, d J = 7.3 Hz) 2F, OCF2C=C, -83.0 (m) 2F, CF2CF2O, -90.9 (d J = 50.6 Hz, each member d J = 39.5 Hz, t J = 7.3 Hz) 1F, cis-CF2CF=CF, -104.5 (d J = 117.6 Hz, each member d J = 50.6 Hz, t J = 25.3 Hz) 1F, trans-CF2CF=CF, -113.0(d J = 5.6 Hz, each member t J = 2.9 Hz) 2F, FSO2CF2, and - 1990.9 ppm (d J = 117.6 Hz, eaaach member d J = 39.5 Hz, t J = 13.8 Hz, t J = 3.2 Hz) 1F, CF2CF =C.

Anal. Calcd for C5F10O3S: C, 18.19; F, 57.55; S, 9.71 Found: C, 18.35; F, 57.40; S, 9.69 EXAMPLE 8 2-(1-Pentafluoro-2-propenyloxy)tetrafluoroethanesulfonyl fluoride

The procedure of Example 7 was followed, substituting acetonitrile for diglyme as the solvent. The acetonitrile was not rigorously purified, and the yields of 2-(1-pentafluoro-2propenyloxy)tetrafuloroethanesulfonyl fluoride, pb 54-55 C (150 mm Hg) ranged from 40-50%.

EXAMPLE 9 1-|1-(Pentafluoro-2-propenyloxy)|hexafluoropropane-2-sulfonyl fluoride

A mixture of potassium fluoride (5.80 g, 0.10 mol) and diglyme (100 ml) was stirred at 10 C while 2-fluorosulfonyltetrafluoropropionyl fluoride (23.0 g, 0.10 mol) (D. C. England, M. A. Dietrich and R. V. Lindsey, Jr., J. Amer. Chem. Soc., 82 6181 (1960)) was added.

The resulting solution was treated at 10 C with perfluoroallyl fluorosulfate prepared as in Example 2A, and after the addition was complete, the mixture was stirred at 25 C for 3 hours, then it was poured into water (500 ml). The lower layer was washed with water (100 ml), dried and distilled to give 1-[1-(pentafluoro-2-propenyloxy)]hexafluoropropane-2sulfonyl fluoride (25.7 g, 0.068 mol, 68%) bp 50 C (60 mm Hg), pure by gas liquid partition chromatography (glpc). The product structure was confirmed by: #max 5.55 (CF=CF2), 6.78 (SO2F) and 7.5-10 m (CF,C-O,SO2); 19F NMR, 54.9 (d J = 20.7 Hz, each member q of J = 10.4 Hz, d J = 3.6 Hz) 1F,SO2F, -71.8 (d J = 25.0 Hz, each member t J = 13.8 Hz, d J = 13.8 Hz, d J = 7.4 Hz) 2F, OCF2C, OCF2C=C, -72.1 (m) 3F, CF3, -75.5 (M) 2F, CFCF2O, -91.0 (D J = 50.7 Hz, each member d J = 39.4 Hz, t J = 7.4 Hz) 1F, cis-CF2CF=CF, -104.6 (d J = 117.6 Hz, each member d J = 50.7 Hz, t J = 25.0 Hz) 1F, trans-CF2CF=CF, 166.4 (d J = 14.6 Hzm, each member q J = 7.2 Hz, d J = 3.6 Hz) 1F, CF, and -191.1 ppm (d J = 117.6 Hz. each member d J = 39.4 Hz, t J = 13.8Hz, t J = 1.7Hz) 1F CF2CE =C.

Anal. Calcd for C6F12O3S: C, 18.96; F, 59.98; S, 8.44 Found: C, 18.70; F, 60.09; S, 8.08 EXAMPLE 10 2-[1-(1,2,3,4,4-Pentafluoro-2-cyclobutenyloxy)]tetrafluoroethanesulfonyl fluoride

A suspension of potassium fluoride (5.80 g, 0.10 mol) in diglyme (100 ml) was stirred and held at 15 C by external cooling while fluorosulfonyldifluoroacetyl fluoride (18.0 g, 0.10 mol) was added rapidly. This mixture was treated at 10-15 C with 1-(1,2,3,4,4-pentafluoro2-cyclobutenyl)-fluorosulfate (24.2 g, 0.10 mol) (B.E. Smart, J. Org. Chm., 41 2353 (1976) and then stirred at 25 C for 3 hours and poured into water (500 ml). The lower layers was washed with water (100 ml), dried and distilled to give 2-[1-(1,2,3,4,4-pentafluoro-2cyclobutenyloxy)]tetrafluoroethanesulfonyl fluoride (24.0 g, 0.07 mol, 70%) bp 62 C (100 mm Hg). The product structure was confirmed by: #max 5.53 (C=C), 6.80 (SO2F) and 8-9.5 m (C-F, C-O, SO2); 19F NMR, 44.8 (t J = 6.0 Hz, each member t J = 6.0 Hz, m) 1F, SO2F, -80.3 and -83.8 (AB J = 146 Hz, each member m) 2F, OCF2, -112.7 (m) 2F CF2SO2F, -117.6 and -119.7 (AB J = 190 Hz, each member m) 2F, ring CF2, -121.8 (m) 1F, CF, -127.1 (m) 1F, CF, and 128.4 ppm (m) 1F, CF, Anal. Calcd for C6F10O3S: C, 21.07; S, 9.37 Found: C, 21.38; S, 9.44 EXAMPLE 11 2-(1-Pentafluoro-2-propenyloxy)-3,6-bis(trifluoromethyl)-2,3,5,5,6-pentafluoro-1,4-dioxane

A mixture of potassium fluoride (5.8 g, 0.10 mol) and diglyme (100 ml) was treated at 25 C with 3,6-bis-(trifluoromethyl)-3,5,5,6-tetrafluoro-1,4-dioxan-2-one (S. Selman, U.S.

Patent 3,321,517) (31.0 g, 0.10 mol). The mixture was stirred for 1 hour and then treated dropwise with perfluoroallylfluorosulfate prepared as in Example 2A (23.0 g, 0.10 mol), the exothermic reaction being maintained at 35-40 C with an external ice bath. The mixture was stirred overnight at 25 C, during which time no gas evolution was detected and a yellow-orange color developed. The mixture was poured into water (500 ml), the lower layer was washed with water (100 ml), dried and distilled at 73-74 C (180-140 mm Hg). The distillate was treated with a small amount of phosphorus pentoxide and refractionated to give 2-(1-pentafluoro-2-propenyloxy)-3,6-bis-(trifluoromethyl)-2,3,5,5,6-pentafluoro-1,4dioxane as a mixture of isomers, bp 55-57 C (60 mm Hg). The product structure was confirmed by: #max 5.57 (CF=CF2) and 7.5-10 m (CF, C-O); 19F NMR, -70.7 and -71.8 (AB J = 159 Hz, each member m) 2F, OCF2C=C, -77.3 and -87.91 (AB J = 153 Hz, each member m) 2F, ring OCF2, -81.4 (m) 4F, CF3 + OCFO, -82.4 (m) 3F, CF3, -92.3 (d J = 52.0 Hz, each member d J = 39.3 Hz, t J = 7.2 Hz) 1 F, cis-CF2CF=CF, -105.3 (d J = 117.1 Hz, each member d J = 52.0 Hz, t J = 25.4 Hz) 1F, trans-CF2CF=CF, -123.3, -124.7, -126.2, -132.2, -132.9 and -134.1 (m) 2F CF3CFO, -190.5 (d J = 117.1 Hz, each member d J = 39.3 Hz, t J = 13.7 Hz) 1F, CF2-CF=C. Small underlying signals caused by the presence of isomers were obscrved at -92.1, -105.3, and -190.5 ppm.

Anal. Calcd for C9F16O3: C, 23.50; F, 66.07 Found: C, 23.71; F, 66.17 EXAMPLE 12 2-[1-(Pentafluoro-2-propenyloxy)]-2,3,5,6-tetrakis(trifluoromethyl)-5-fluoro-1,4,7trioxabicyclo[2.2.1]heptane and 2-[1-(pentafluoro-2-propenyloxy)tetrafluoroethyl]-4-[1 (pentafluoro-2-propenyloxy)]-2,4,5-tris(trifluoromethyl)-5-fluoro-1,3-dioxolane

A suspension of anhydrous potassium fluoride (5.80 g, 0.10 mol) in diglyme (100 ml) was stirred at 10 C while hexafluoro-2,3-butanedione (hexafluorobiacetyl, L. O. Moore and J.W. Clark, J. Org. Chem., 30, 2472 (1965)) (19.4 g, 0.10 mol) was distilled in. The mixture was stirred until the potassium fluoride had nearly all dissolved, and then it was treated rapidly with perfluoroallyl fluorosulfate as in Example 2A (23.0 g, 0.10 mol) at 15 C. The slightly exothermic reaction raised the temperature to 30 C. The pale yellow mixture was stirred overnight at 25 C and then distilled. The two phase distillate collected at bp 49-54 C (10 mm Hg) was shaken with concentrated sulfuric acid (8 ml), treated with anhydrous calcium sulfate and fractioned in a spinning-band still. 2-[1-(Pentafluoro-2propenyloxy)]-2,3,5,6-tetrakis(trifluoromethyl)-5-fluoro-1, 4,7-trioxabicyclo[2.2.1]heptane (3.0 g. 0.0055 mol, 11%) bp 50-51 C (15 mm Hg) contained one major component by glpc.

The analytical sample of this product was obtained by preparative glpc and its structure confirmed by: #max 5.58 (CF=CF2), and 7.5-10 m (C-F,C-O); 19F NMR, -65.6 and -71.0 (AB J = 155 Hz, each member m), 2F, OCF2, -74.7 (m) 3F, CF3, -78.5 (m) 3F, CF3, -79.3 (s) 3F, CF3, -79.9 (d J = 13 Hz, each member septet J = 4 Hz), 3F, CF3, -92.0 (d J = 52.1 Hz, each member d J = 39.5 Hz, d J = 8.3 Hz, d J = 6.6 Hz) 1F, cis-CF2CF=CF, -105.5 (d J = 117.2 Hz, each member d J = 52.1 Hz, d J = 27.0 Hz, t J = 21.8 Hz, q J = 3.0 Hz) 1F, trans-CF2CF=CF - 121.7 (qJ = 20.5 Hz, each member qJ = 13.1 Hz)1F, CF, and -191.2 ppm (d J = 117.2 Hz, each member d J = 39.5 Hz, t J = 13.8 Hz) 1F, CF2-CF =C.

Anal. Calcd for C11F18O4: C, 24.55; F, 63.55 Found: C, 24.57; F, 63.60 The second fraction was a mixture of isomers of 2-[1-(pentafluoro-2propenyloxy)tetrafluoroethyl]-4-[1-(pentafluoro-2-propenyloxy)]-2,4,5tris(trifluoromethyl)-5-fluoro-1,3-dioxolane (7.2 g, 0.01 mol, 21%), which contained only minor impurities by glpc. This product structure was confirmed by: #max 5.56 (CF=CF2) and 7-10 m (CF2C-O), 19F NMR -72.8 ppm (AB) 2F, OCF2, -75.4, -76.8, -78.3, -78.7 and -79.1 (m) 12F, CF3, -93.1 (m) 2F cis-CF2CF=CF, -105.8 (m) 2F, trans-CF2CF=CF, -121.0, -136.5 and -141.6 (m) 2F, CF, and -190.8 ppm (m) 2F, CF2CF=C.

Anal. Calcd for C14F24O4: C, 24.44; F, 66.26 Found: C, 24.73; F, 66.48 EXAMPLE 13 Perfluoro-1,6-(2-propenyloxy)hexane

diglyme CF2=CFCF2O(CF2)5COF + H2O # CF2=CFCF2O(CF2)5CCO2H. diglyme A mixture of potassium fluoride (11.62 g, 0.20 mol), diglyme (200 ml) and octafluoroadi poyl difluoride (PCR 28.2 g. 0.096 mol) was stirred at 5 C for 1.5 hours. The mixture was kept at 5-10 C while perfluoroallyl fluorosulfate prepared as in Example 2A (46.0 g, 0.20 mol) was added dropwise. When the addition was complete, the mixture was stirred at 5 C for 30 min, then it was allowed to warm to 25 C and the stirring was continued for a further 3 hours. After having stood overnight, the mixture was poured into water (1 l.); the lower layer was washed with water (150 ml), dried and distilled to give two products.

The lower-boiling fraction was perfluoro-1,6-bis-(2-propenyloxy)hexane (21.2 g, 0.0355 mol, 37%), bp 84-86 C (20 mm Hg) whose structure was confirmed by: #max 5.59 (CF=CF2) and 7.2-9.5 m (C-F,C-O); 19F NMR, -72.1 (d J = 25.7 Hz, each member t J = 13.3 Hz, d J = 13.3 Hz, t J = 7.6 Hz) 2F, OCF2C=C, -84.1 (m) 2F, CF2O, -92.3 (d J = 52.7 Hz, each member d J = 39.5 Hz, t J = 7.6 Hz) 1F, cis-CF2CF=CF, -105.5 (d J = 117.8 Hz, each member d J = 52.7 Hz, t J = 25.7 Hz) 1F, trans-CF2CF=CF, -122.9 (m), CF2, - 126.2 (m) 2F, CF2, and -191.0 ppm (d J = 117.8 Hz, each member d J = 39.5 Hz, t J = 13.8 Hz) 1F, CF2-CF=C.

Anal. Calcd for C12F22O2: C, 24.26; F, 70.35 Found: C, 24.43; F, 70.38 The higher boiling fraction was the 2:1 complex of perfluoro-6-(2-propenyloxy 52.3 Hz, t J = 25.1 Hz), 1F, trans-CF2CF=CF, -119.6 (t J = 12.6 Hz, each member t J = 3.2 Hz) 2F, CF2, -122.6 (m) 2F, CF2, -123.5 (m) 2F, CF2, -126.1 (m) 2F, CF2, and -190.9 ppm (d J = 117.7 Hz, each member d J = 39.3 Hz, t J = 13.8 Hz, t J = 1.8 Hz 1F, CF2CE=C.

EXAMPLE 14 Methyl Perfluoro-3,6-dioxanon-8-enoate

A suspension of 42 g (1.0 mol) of NaF in 100 ml of methanol was stirred at 5 C while 114 g (0.317 mol) of acid fluoride was added rapidly. After addition had been completed the mixture was stirred overnight at 25 C, filtered and the solid rinsed with ether. Distillation afforded 102.0 g (86%) of methyl perfluoro-3,6-dioxanon-8-enoate, bp 60-61 C (20 mm Hg), containing small amounts of impurities. Redistillation gave somewhat more pure ester (1-2% impurities by gc), bp 61-62 C (20 mm Hg). Structure was confirmed by Ir (neat): 3.32, 3.37, 3.49 (CH3), 5.57 (C=O), 8-9.5 (CF, C-O), NMR; H 3.95 ppm (s) with small impurities at 3.53 and 3.33 ppm; 19F -72.0 (d of d of t of d, JFF 24, 13, 13, 7.5 Hz, 2 F, =CFCF2), -78.0 (t, JFF 11.6 Hz, 2 F, CF2CO2CH3), -89.0 (t, JFF 11.6 Hz, 2 F, CF2OCF2CO2CH3), -89.5 (t, JFF 12.6 Hz, 2 F =CFCF2OCF2), -92.3 (d of d of t, JFF 53.2, 39.2, 7.5 Hz, 1 F, cis-CF2CF=CF), -105.2 (d of d of t, JFF 117.3, 53.2, 24.3 Hz, 1F, trans-cf2CF-CF), and -190.8 ppm (d of d of t of t, JFF 117.3, 39.2, 14.0, 1.6 Hz, 1 F, CF2CF=).

Anal. Calcd for c8H3F11O4: C, 25.82; H, 0.81; F, 56.17 Found: C, 26.17; H, 0.66; F, 56.24.

EXAMPLE 15 EXAMPLE 1@ Dimethyl Perfluoro-3-alloxyglutarate A. Bis(2-methoxytetrafluoroethyl)ketone The svnthesis of bis( 2-methoxytetrafluoroethy I)ketone from dimethyl carbonate tetrafluoroethylene, and sodium methoxide has been described by D. W. Wiley (U. S. 2.988,53/ (1961)). An extension of this synthesis has given 1,3,3,5-tetrafluoromethoxyoctafluoropentane in a one-pot reaction.

A mixture of 27.0 g (0.50 mol) of sodium methoxide, 56.0 g (0.62 mol) of dimethyl carbonate, and 100 ml of dry tetrahydrofuran was agitated in a 350 ml tube under 1-3 atm of tetrafluoroethylene. Tetrafluoroethylene was pressured in as consumed until 110 g (1.1 mol) had been added. The mildly exothermic reaction kept the temperature near 35 C; after the addition, the reaction mixture was heated at 40 C for 1 hour. The viscous solution from this reaction was treated directly with 75.6 g (0.60 mol) of dimethyl sulfate at 40 C for 15 hours. Filtration and distillation afforded 87.6 g (52%) of 1,3,3,5 tetramethoxyoctafluoropentane, bp 54 C (0.3 mm Hg), nD24 1.3605, whose structure was confirmed by Ir 3.29, 3.33, and 3.42 (satd CH), 8-9 (CF, COC). Nmr (CCl4), 'H # 3.68 (s, 1, CF2OCH3) and 3.57 (p, JHF 1.3 Hz, 1, C (OCH3)2); 19F -88.2 (m, 1, CR2O) and -116.5 ppm (m, 1, CF2).

Anal. Calcd. for C9H12F8O4: C, 32.16; H, 3.60; F, 45.21 Found: C, 32.57; H, 3.72; F, 44.61.

B. Dimethyl Tetrafluoroacetone-1,3-dicarboxylate CH3OCF2CF2C(OCH3)2CF2CF20CH3

To 50 ml of conc. H2SO4 was added dropwise 33.6 g (0.10 mol) of the tetraether. After the mildly exothermic reaction had subsided, the mixture was heated at 70 C (50 mm Hg) to remove volatiles and then distilled at ca. 50 C (1 mm Hg). The crude distillate was then fractionated to afford 16.9 g (69%) of dimethyl tetrafluoroacetone-1,3-dicarboxylate, bp 58 C (2 mm), nD22 1.3713. Structure was confirmed by Ir 3.28, 3.34 and 3.48 (satd CH), 5.57 (C=O) 5.64 (sh-C=O), 8-9 (CF, COC). Nmr (CCl4) 'H # 4.00 (s, OCH3); 19F -113 ppm (s, CF2).

Anal. Calcd. for C7H6F4O5 C, 34.16; H, 2.46; F, 30.88 mol wt, 246 Found: C, 34.18; H, 2.66; F, 30.9S; mol wt, 246 (mass spec).

The same reaction on a ().56 mole scale gave the diester in 82% yield.

C. Dimethyl Perfluoro-3-alloxyglutarate

To 27.3 g (0.18 mol) dry CsF in 100 ml diglyme was added 43.5 g (0.18 mol) O=C(CF2COOCH3)2 at 5-10 C and stirred for 1 hour; 41.4 g (0.18 mol) CF2=CFCF2O SO2F was added at 5-10 C and the mixture was stirred further for 3 hours. The reaction mixture was thrown into 1 liter of H2O and the lower layer separated. This was washed twice with H2O. After treatment with 20 ml H2SO4 at 0 C and extraction with FreonR 113, the extract was distilled in a molecular still to give 4.54 g (7.2% yield) of product, bp = 51-53 C (0.1 mm). Structure was confirmed by 19F nmr (F11): -68.48 ppm (OCF2CF=); -93.45 ppm cis-(CF=CFF); -105.91 ppm trans-(CF=CF); -117.10 ppm (CF2COOCH3); -142.78 ppm (CF2CF2OCF=); -190.35 ppm (CF=CF2). 'H nmr (F11/TMS): 3.96 (singlet, CH3). Ir (neat): 3.37 , 3.49 (sat CH); 5.60 2 ( C=O, CF2=CF); 8-10 (CF, CO).

Anal. Calcd for C10F10H6O5: C, 30.32, F, 47.96; H, 1.53 Found: C, 30.45; F, 48.10 H, 1.48.

EXAMPLE 16 Perfluoro-3-(2-propoxy-2-methylethoxy)propene

A mixture of potassium fluoride (6.96 g, 0.12 mol), diglyme (150 ml) and 2-(1heptafluoropropoxy)tetrafluoropropionyl fluoride (dimer of hexafluoropropene oxide obtained bv treatment with fluoride ion) (29.4 g, 0.089 mol) was stirred at 50C for 1 hour.

Perfluoroallyl fluorosulfate prepared as in Example 2A (27.6 g 0.12 mol) was added dropwise at 5 C, then the mixture was stirred at 5 C for 3 hours, and at 25 C overnight. The reaction mixture was poured into water (1 l.), the lower layer was separated and the volatile components were removed at 25 C (0.5 mm Hg). Distillation of the volatile components from concentrated sulfuric acid gave perfluoro-3-(2-propoxy-2methylethoxy)propene (25.2 g, 0.052 mol, 59%), bp 62-63 C (100 mm Hg) whose structure was confirmed by: #max 5.57 (CF=CF2) and 7.5-9 m (C-F, C-O); 19F NMR, -72.2(d J = 25.5 Hz, each member t J = 13.3 Hz, d J = 13.3 Hz, d J = 7.4 Hz) 2F, OCF2C=C, -81.0 (m) 3F, CF3, -82.3 (m) 5F, CF3 + OCF2, -84.1 (m) 2F, CF2O, -92.1 (d J = 52.7 Hz, each member d J = 39.7 Hz, t J = 7.4 Hz) 1F, cis-CF2CF=CF, -105.5 (d J = 117.8 Hz, each member d J = 52.7 Hz, t J = 25.5 HZ(, 1/8F, trans-CF2CF=CF, -130.4 (s) 2F, CF2, -145.9 (m) 1F, CF, and --191.0 ppm (d J = 117.8 Hz, each member d J = 39.7 Hz, t J = 13.6 Hz) IF, CF2CF=C.

Anal. Calcd for C9H18O2: C, 22.42; F, 70.94 Found: C, 22.18; F, 70.96 EXAMPLE 17 Perfluoro-1,3-bis(2-propenyloxy)propane

A mixture of potassium fluoride (15.3 g, 0.26 mol), diglyme (200 ml) and difluoromalonyl dilfuoride prepared as in Example 5A (17.3 g. 0.12 mol) was stirred at 5 C for 15 min.

Perfluoroallyl fluorosulfate (57.5 g, 0.25 mol) was added at 5-10 C over a 45 min period, and the mixture was stirred at 5 C for an additional hour, then at 25 C for 2 hours. The reaction mixture was poured into water (1 l.), the lower layer was washed with water (100 ml), dried and distilled to give perfluoro-1,3-bis (2-propenyloxy)propane (12.0 g, 0.027 mol, 23%) bp 88-90 C (200 mm Hg) whose structure was confirmed by: #max 5.59 (CF=CF2) and 7.2-9.5 m (C-F,C-O); 19F NMR, -72.2 (m) 2F, OCF2C=C, -84.6 (m) 2F, CF2CF2O, -92.3 (d J = 53.0 Hz, each member d J = 39.5 Hz, t J = 7.2 Hz) 1F, cis-CF2CF=CF, -105.6 (d J = 117.8 Hz, each member d J = 53.0 Hz, t J = 25.2 Hz) 1F, trans-CF2CF=CF, -130.0 (s) 1F. CF2 and -191.0 ppm (d J = 117.8 Hz, each member d J = 39.5 Hz, t J 13.5 Hz) 1F, CF2CF=C.

Anal. Calcd for C9F16O2: C, 24.34; F, 68.45 Found: C, 24.67; F, 68.36 EXAMPLE 18 Perfluoro-3-(butoxy)propene CF3CF2CF2COF + KF + CF2=CFCF2OSO2F # CF3CF2CF2CF2OCF2CF=CF2 A mixture of dry potassium fluoride (7.50 g, 0.13 mol), diglyme (100 ml) and heptafluorobutyroyl fluoride (prepared from the acid by treatment with sulfur tetrafluoride) (28.1 g, 0.13 mol) was stirred at 5 C for 30 min. Perfluoroallyl fluorosulfate was added dropwise at 5 C, the mixture was stirred at this temperature for 1 hour, then at 25 C for 3 hours. The volatile components were transferred by distillation at 40 C (8 mm Hg), washed with water (100 ml), and distilled from a small amount of concentrated sulfuric acid to give perfluoro-3-(butoxy)propene (30.3 g, 0.083 mol, 64%) bp 80-84 C whose structure was confirmed by: #max 5.57 (CF=CF2) and 7.2-9.5 m (CF,C-O); 19F NMR -72.1 (d J = 25,2 Hz, each member t J = 13.5 Hz, d J = 13.5 Hz, d J = 7.4 Hz) 2F, OCF2C=C, -82.1 (t J = 8.1 Hz, each member m), 3F, CF3, -84.5 (m) 2F, CF2O, -92.1 (d J = 52.3 Hz, each member d J = 39.4 Hz, t J = 7.4 Hz) 1F, cis-CF2CF=CF, -105.5 (d J = 117.5 Hz, each member d J = 52.3 Hz, t J = 25.2 Hz) 1F, trans-CF2CF=CF, -127.3 (m) 4F, CF2 and -191.0 ppm (d J = 117.5 Hz, each member d J = 39.4 Hz, t J = 13.7 Hz, m) 1F, CF2CF =C.

Anal. Calcd for C7F14O: C, 22.97; F, 72.66 Found: C, 23.20; F, 72.80 EXAMPLE 19 EXAMPLE 19 Perfluoro-3-(octyloxy)propene F(CF2)7COF + KF + CF2=CFCF2OSO2F # F(CF2)8OCF2CF=CF2 A mixture of potassium fluoride (5.80 g, 0.10 mol), diglyme (150 ml) and pentadecaf luorooctanoyl fluoride (prepared by treating commercial perfluorooctanoic acid with sulfur tetrafluoride) (25.0 g. 0.06 mol) was stirred at 5 C for 1 hour. Perfluoroallyl fluorosulfate (23.0 g, 0.10 mol) was added dropwise and the mixture was stirred at 5 C for 4 hours, then at 25 C for an additional 3 hours. The mixture was poured into water (1 l.), separated, and the lower layer was distilled from concentrated sulfuric acid to give perfluoro-3 (octyloxy)propene (27.1 g, 0.048 mol, 80%) bp 69-70 C (20 mm Hg) whose structure was confirmed by: #max 5.59 (CF=CF2) and 8-9 m (CF C-O); 19F NMR -71.8 (d J .046 25.1 Hz, each member d J = 13.4 Hz, t J = 13.4 Hz, d J = 7.7 Hz) 2F, OCF2C=C, -81.6 (t J = 10.0 Hz) 3F, CF3, -83.8 (m) 2F, CF2CF2O, -92.3 (d J = 53.6 Hz, each member d J = 39.9 Hz, t J = 7.7 Hz) 1F, cis-CF2CF=CF, -105.5 (d J = 117.8 Hz, each member d J = 53.5 Hz, t J = 25.1 Hz) 1F, trans-CF2CF=CF, -122.2 (m) 6F, CF2, -122.9 (m) 2F, CF2, -125.7 (m) 2F, CF2, -126.5 (m) 2F, CF2, and -190.8 ppm (d J = 117.8 Hz, each member d J = 39.9 Hz, t 13.7 Hz, t 1.7 Hz) 1F, CF2CF=C.

Anal. Calcd for C11F22O: C, 23.34; F, 73.84 Found: C, 22.99; F, 73.94 EXAMPLE 20 2-Trifluoromethoxypentafluoropropene (Perfluoro(allylmethylether))

A mixture of carbonyl fluoride (18.0 g, 0.27 mol), cesium fluoride (38.0 g, 0.25 mol) and dry diglyme (300 ml) was stirred at -20 C to -10 C for 2 hours, then kept at -10 C or below while perfluoroallyl fluorosulfate (46.0 g, 0.20 mol) was added. The mixture was stirred at -10 C for 2 hours, at 0 C for 2 hours, then at 25 C overnight. The mixture was warmed under a slight vacuum, and the volatile distillate (11 ml of liquid collected at -80 C) was redistilled through a low temperature still to give 2-trifluoromethoxypropene (3.2 g, 2.0 ml at -80 C, 0.014 mol. 7%) bp 11-12 C. The structure was established by its spectra: #max (gas phase) 5.55 (CF=CF2), 8-9 (CF, C-O) and 5.35 m (weak COF impurity band); 19F NMR (CCl4), -56.5 (t J = 9.2 Hz) 3F, CF3O, -74.6 (d J = 25.8 Hz, each member d J = 13.6, q J = 9.2 Hz, d J = 7.1 Hz) OCF2C=C; -92.2 (d J = 53.4 Hz, each member d J 0 39.2 Hz, t J = 7.1 Hz) 1F, cis-CF2CF=CF, -105.5 8d J = 118.0 Hz, each member d J = 53.4 hz, t J = 25.8 Hz), 1F, trans-CF2CF=CF, and -190.9 ppm (d J = 118.0 Hz, each member d J = 39.2 hz, t J = 13.6 Hz) 1F, CF2CF=C.

EXAMPLE 21 Perfluoro-6-(2-propenyloxy)hexanoic Acid and Its Methyl Ester FCO(CF2)4COF + KF + CF2 = CFCF2OSO2F # (CF2 = CFCF2OCF2CF2CF2)2 + CF2 = CFCF2O(CF2)5COF

H2SO4 (CH3OCH2CH2OCH2CH2OCH3) # CF2 = CFCF2O(CF2)5CO2H + distil CF2 = CFCF2O(CF2)5CO2CH3 A mixture of potassium fluoride (11.7 g, 0.20 mol), diglyme (250 ml) and octafluoroadipoyl difluoride (PCR 58.8 g, 0.20 mol) was stirred at 0-5 C for 30 min. The mixture was kept at 0-5 C while perfluoroallyl fluorosulfate (Example 2A, 46.0 g, 0.20 mol) was added dropwise. When the addition was complete, the mixture was stirred at 0-5 C for 2 hours, then it was allowed to warm to 25 C and the stirring was continued for a further 4 hours.

Evacuation of the reaction mixture to 35 C (3 mm Hg) removed 45 ml of liquid. The higher boiling residue was poured in water (11.): the lower layer (10 ml) was combined with the volatile fraction from above and treated with a mixture of water (100 ml) and diglyme (20 ml). After the resulting exothermic reaction, the mixture was allowed to cool, and the lower layer was separated and distilled to give perfluoro-1,6-bis(2-propenyloxy)hexane (Example 13. 13.6 g, 0.023 mol. 23%) bp 61 (6 mm Hg) and the 2:1 complex of perfluoro-6-(2propenyloxy)hexanoic acid with diglyme (Example 13, 52.8 g, 0.109 mol, 54.5%) bp 82-84 C (0.8 mm Hg).

The diglyme complex of the higher boiling fraction was distilled from concentrated sulfuric acid (40 ml) to give perfluoro-6-(2-propenyloxy)hexanoic acid containing 12% of its methyl ester. The ester arises from the action of sulfuric acid on the diglyme present in the complex. These products were identified by infrared #max 2.82 and 3-4 (OH, CH3), 5.58 (CF=CF2), 5.61 (C=O) and 7-10 m (CF,C-O,CH) and by H NMR, # 3.92 (OCH3) and 11.33 ppm (OH) signals in the ratio of 1:7.2; the 19F NMR spectrum was also in accord with these structures.

EXAMPLE 22 Perfluoro-6- (2 -p ropenyloxy) hexanoic Acid A reaction was carried out as described in Example 21. The crude reaction mixture was poured into water (750 ml), and the lower layer was washed with water (100 ml). The same two products were obtained as in Example 21 by distillation of the crude lower layer. The fraction bp 45-53 C (6 mm Hg) was freed of diglyme by water washing to leave crude perfluoro-1, 6-bis(2-propenyloxy)hexane (9.5 g, 0.016 mol, 16%).

The higher boiling complex of perfluoro-6-(2-propenyloxy)hexanoic acid with diglyme was dissolved in 1,1,2-trichloro-1,2,2-trifluoroethylene (50 ml) and extracted in turn with 50 ml and 25 ml of concentrated sulfuric acid. The organic layer was treated with calcium sulfate, filtered, and distilled to give pure perfluoro-6-(2-propenyloxy)hexanoic acid (42.2 g, 0.0988 mol, 49%) bp 75 C (1.0 mm Hg). This material was identified by infrared #max 2.85-4.0 (H-bonded OH), 5.57 (CF=CF2), 5.63 (sh,C=O) and 8-9 m (CF,C-O), and by its H and 19F NMR spectra.

Anal. Calcd. for C9HF15O3: C, 24.45; H, 0.23; F, 64.66 Found: C, 24.48; H, 0.45; F, 65.76 The following examples illustrate the preparation of useful copolymers from the polyfluoroallyloxy comonomers of this invention. The general properties of these copolymers were discussed above.

UTILITY EXAMPLES EXAMPLE A Solution Polymerization of Tetrafluoroethylene with 2-[1-(Pentafluoro-2propenyloxy)]tetrafluoroethanesulfonyl Fluoride

An 80-ml stainless stell-lined tube was charged with a cold mixture (-45 C) of 1,1,2-trichloro-1,2,2-trifluoroethane (FreonR 113) (10 ml), 8% 1,1,2-trichloro-1,2,2trifluoroethane solution of pentafluoropropionyl peroxide (3P initiator) (1 ml), and 2-[ 1 -(pentafluoro-2-propenyloxy)j-tetrafluoroethanesulfonyl fluoride (Example 7, 17.5 .

0.053 mol). The tube was closed, cooled to -40 C, evacuated, and charged with tetrafluoroethylene (20 g, 0.20 mol). The tube was warmed to 25 C and shaken at this temperature for 20 hours. The volatile materials were allowed to evaporate, and the product polymer was evacuated to 0.5 mm Hg. The product was then extracted with 1,1,2-trichloro-1,2,2-trifluoroethane, and dried under vacuum to give the solid white copolymer (16.9 g, 85%): #max (KBr) 6.79 (SO2F) and 12.3 m (broad) in addition to the usual polytetrafluoroethylene infrared bands. Gravimetric sulfur analysis gave 0.48 and 0.20% S, corresponding to an average of 0.34% S or 3.5 wt. % (1.1 mole %) of polyfluoroallyloxy comonomer corresponding to an equivalent weight of 9400. Equivalent weight is the molecular weight of the polymer per functional group (here -SO2F). Differential scanning calorimetry (DSC) showed a 12% depression of the endotherm peak (mp) compared to polytetrafluoroethylene.

EXAMPLE B Solution Polymerization of Tetrafluoroethylene with 1-[1-(Pentafluoro-2propenyloxy)]hexafluoropropane-2-sulfonyl Fluoride

The procedure of Example A was followed with 1,1,2-trichloro-1,2,2-trifluoroethane (10 ml). 8% pentafluoropropionyl peroxide in 1,1,2-trichloro-1,2,2-trifluoroethane (2.0 ml), 1-[1-(pentafluoro-2-propenyloxy)]hexafluoropropane-2-sulfonyl fluoride (Example 9, 17.4 g 0.046 mol) and tetrafluoroethylene (20 g, 0.20 mol) to give 16.7 g (79%) of copolymer.

Analysis bv X-ray fluorescence showed 0.49 % S present, corresponding to 5.8 wt-% (1.6 mole %) of polyfluoroallvloxv comonomer corresponding to an equivalent weight of 6540.

The sample had a mp depression of 11 C compared to polytetrafluoroethylene by DSC.

EXAMPLE C Solution Polymerization of Tetrafluoroethylene with 3-[1-(Pentafluoro-2propenyloxy)tetrafluoropropionyl Fluoride

The procedure of Example A was used with 3-[-1(pentafluoro-2propenyloxy)]tetrafluoropropionyl fluoride (Example 5, 13.3 g, 0.045 mol) in place of 2-[1-(pentafluoro-2-propenyloxy)]-tetrafluoroethanesulfonyl fluoride to give 17.8 g (86%) of copolymer: #max (KBr) 5.62 (CO2H, weak) and 9.7 m bands in addition to the polytetrafluoroethylene bands; mp depression (DSC) was 14 C compared to polytetrafluoroethylene; gravimetric analysis showed 3.7 wt % of polyfluoroallyloxy comonomer corresponding to an equivalent weight of 7900.

A sample of the polymer was stirred with a solution of sodium hydroxide in 336Xc ethanol for 2 days. filtered. and washed with water until the extracts were no longer basic. The resulting polymer, now readily wetted by water, was dried under vacuum. Analysis by atomic absorption spectroscopy showed 0.29% Na, corresponding to 3.7 wt-% (1.3 mole %) of the original comonomer.

EXAMPLE D Solution Polymerization of Tetrafluoroethylene with 1 - (1,1,1,2,3, 3-Hexafluoro-3-chloro-2- propoxy)pentafluoro-2-propene

The procedure of Example A was used with 1-(1,1,1,2,3,3-hexafluoro-3-chloro-2 propoxy)pentafluoro-2-propene (Example 2, 14.3 g, 0.043 mol) in place of 2-[1 (pentafluoro-2-propenyloxy)]-tetrafluoroethanesulfonyl fluoride to give 18.3 g (87%) of copolymer: mp depression (DSC) 14 C compared to polytetrafluoroethylene; gravimetric analysis gave 0.61 and 0.61% Cl, corresponding to 5.7 Wt-% of polyfluoroallyloxy comonomer and an equivalent weight of 5800; more accurate analysis by X-ray fluorescence gave 0.53% Cl corresponding to 5.0 wt-% (1.56 mole %) of polyfluoroallyloxy comonomer.

The mp depression of 14 C compared to polytetrafluoroethylene corresponds to a depression of 1 C per 0.1 mol % of poly-fluoroallyloxy comonomer present. In contrast to this result, the smaller branch in hexafluoropropene gives a mp depression corresponding to about 1 C per 0.3 mol-% of comonomer in its copolymer with tetrafluoroethylene. This means that the copolymers prepared from the polyfluoroallyloxy comonomers have better molding properties for the same mol-% incorporation of comonomer than those prepared from hexafluoropropene comonomer.

EXAMPLE E Solution Polymerization of Tetrafluoroethylene with 2-(1-Pentafluoro-2propenyloxy)hexafluoropropane-1-sulfonyl Fluoride

The procedure of Example A was used with 2-(1-pentafluoro-2propenyloxy)hexafluoropropane-1-sulfonyl fluoride (Example 3, 16.1 g, 0.042 mol) in place of 2-[1-pentafluoro-2-propenyloxy)]tetrafluoroethanesulfonyl fluoride to give 18.5 g (88%) of copolymer: mp depression (DSC) 8 C compared to polytetrafluoroethylene; analysis by X-ray fluorescence showed 0.43% S, corresponding to 5.1 wt-% (1.4 mole %) of polyfluoroallyloxy conomomer and an equivalent weight of 7460.

EXAMPLE F Solution Polymerization of Vinylidene Fluoride with 2-[1-(Pentafluoro-2propenyloxy)]tetrafluoroethanesulfonyl Fluoride

CH2=CF2 + CF2 = CFCF2OCF2CF2SO2F > Copolymer The procedure of Example A was used with vinylidene fluoride (20 g, 0.32 mol), 2-[1-(pentafluoro-2-propenyloxy)]tetrafluoroethanesulfonyl fluoride (Example 7, 16.5 g, 0.05 mol), 1,1,2-trichloro-1,2,2-trifluoroethane (10 ml), and 8% 1,1,2-trichloro-1,2,2trifluoroethane solution of pentafluoropropionyl peroxide (5 ml). The mixture was shaken overnight, the maximum recorded temperature being 31 C. The solid copolymer produced (21.5 g, 60%) contained 46 wt % (14.2 mol %) of polyfluoroallyloxy comonomer with an equivalent weight of 71.9 DSC showed no thermal events between 25 C and 400 C.

Anal. Calcd for (CH2=CF2)6.05 (CF2=CFCF2OCF2CF2SO2F): C, 28.62; H, 1.70; S, 4.47 Found: C, 28.49; H, 1.71; S, 4.46 EXAMPLE G Solution Polymerization of Vinylidene Fluoride with 1-(Heptafluoro-2-propoxy)-1,1,3,3tetrafluoro-2-chloro-2-propene

CH2=CF2 + CF2 = CCICF2OCF(CF3)2 # Copolymer The procedure of Example F was used with 1-(heptafluoro-2-propoxy)-1,1,3,3- tetrafluoro-2-chloro-2-propene (Example 1, 10.5 g, 0.032 mol) in place or 2-[1 (pentafluoro-2-propenyloxy)[tetrafluoroethanesulfonyl fluoride to give a solid copolymer (20.6 g, 73%). This material contained 36 wt-% (9.8 mol-%) of polyfluoroallyloxy comonomer with an equivalent weight of 878. DSC confirmed the structure as a copolymer and indicated its stability, because no thermal events were observed in the range 25-400 C.

EXAMPLE H Solution Polymerization of Tetrafluoroethylene with Perfluoro.3-(butoxy)propene

CF2=CF2 + CF3(CF2)3OCF2CF=CF2 # Copolymer The procedure of Example A, when used with perfluoro-3-(butoxy)propene (Example 18. 19.0 g, 0.052 mol), tetrafluoroethylene (20 g, 0.20 mol), 1,1,2-trichloro-1,2,2trifluoroethane (10 ml) and 8% pentafluoropropionyl peroxide in 1,1,2-trichloro-1,2,2 trifluoroethane (2 ml) gave 18.9 g of solid copolymer. This crude material was chopped in a blender with more solvent. rinsed, and dried to give 16.5 g of copolymer with a mp of 309 C, indicating that it was a true copolymer.

EXAMPLE 1 Solution Polymerization of Tetrafluoroethylene with Perfluoro-1,6-bis(2- propenyloxy) hexane

CF2=CF2 + (CF2=CFCF2OCF2CF2CF2)2 # Copolymer The procedure of Example H was followed using perfiuoro-1,6-bis(2- propcnyloxy)hexane (Example 13, 20 g. 0.20 mol) for the polyfluoroallyloxy monomer.

This gave 16.3 g of dry pulverized polymer with #max 5.55 m (CF=CF2); the remainder of the infrared spectrum resembled that of poly(tetrafluoroethylene). DSC showed a pronounced exotherm Tp 315 C followed by an endotherm Tp ~ 333 C and 339 C on the first heating; the second heating showed no exotherm and a broad endotherm Tp ~ 326 C.

Infrared spectra indicated that pyrolytic reactions of pendant pentafluoroallyloxy groups had occurred during the first heating; the broad DSC cndotherm near the normally sharp mp of poly(tctrafluorocthylcnc) indicates that crosslinking had occurred.

EXAMPLE J Solution Polymerization of Vinylidene Fluoride and Perfluoro-1 , 3-bis(2- propenyloxy)propane

CH2 = CF2 + (CF2=CFCF2OCF2)CF2 # Copolymer A mixture of perfluoro-1,3-bis(2-propenyloxy)-propane (Example 17, 5.7 g, 0.013 mol), 1.1 ,2-trichloro-1,2,2-trifluorocthanc (25 ml), and 8% pentafluoropropionyl peroxide in 1,1,2-trichloro-1,2,2-trifluoroethane (5 ml) was held at -40 C in a stainless steel-lined shaker tube while vinylidene fluoride (20 g, 0.32 mol) was condensed into the tube. The mixture was shaken overnight at room temperature, and the product was isolated as described above. The crude polymer was dried under vacuum, pulverized in a blender with 95% ethanol. filtered and dried to give 24.0 g of solid copolymer. DSC showed an endotherm Vp 124 C, stable to at least 3()()0C, indicating that a true copolymer had been formed since poly(vinylidene fluoride) has mp 171 C. The insolubility of this product in acetone and the lack of absorption bands in the infrared for pendant CF=CF2 groups indicates that crosslinking had occurred.

EXAMPLE K Copolymer 9/ TFE with Methyl Perfluoro-3,6-dioxanon-8-enoate 45 g of methyl pcrfluoro-3 .6-dioxanon-X-enoate and 0.04 g of perfluoropropionyl peroxide were reacted at 5()0C for 4 hr. under a 10 psi pressure of tetrafluoroethylene.

Filtration gave a solid which on drying at 50 C in a vacuum oven weighed 0.71 g. The amount of TFE added was 4 g. Equivalent weight by titration gave 1176; therefore the amount of the ester incorporated in the polymer was 28% and the yield based on TFE was 20%. A transparent film was obtained by heating at 220 C in a Carver press.

EXAMPLE L Dyeable Fluorocarbon Polymers Samples of the polymers of Examples B and E were treated with aqueous alcoholic ammonia solution for one day at 25 C, filtered, washed with aqueous ethanol and dried under vacuum.

A sample of the polymer of Example C was similarly treated with aqueous alcoholic sodium hydroxide.

The above partly hydrolyzed polymers were immersed in aqueous ethanol solutions of SevronR Red GL (SevronR is a line of cationic dyes especially suited for dyeing OrlonR and other acrylic fibers, having outstanding fastness and brilliance - Du Pont Products Book, January 1975. p. 34) at 25 C for 1-3 hours, then they are extracted until the extracts no longer contained dye. All three samples dyed well to an orange-red color.

EXAMPLE M Wettable Fluorocarbon Polymer A sample of the polymer of Example C was treated with aqueous alcoholic sodium hydroxide as described in Example L. The resulting fluorocarbon polymer contained carbonyl groups and was wettable with water.

EXAMPLE N Emulsion Polymerization of Tetrafluoroethylene with 2-[1-(Pentafluoro-2propenyloxy)]tetrafluoroethanesulfonyl Fluoride

CF2=CF2 + CF2=CFCF2OCF2CF2SO2F ) Copolymer A stainless steel shaker tube was charged with water (140 ml), 1,1,2-trichloro-1,2,2- trifluoroethane (10 ml), 2-[1-)pentafluoro-2-propenyloxy)]tetrafluoroethanesulfonyl fluoride (Example 7, 6.0 g), potassium perfluorooctanesulfonate (0.16 g), ammonium carbonate (0.50 g) and ammonium persulfate (0.5() g). The mixture was brought to an internal pressure of 200 p.s.i.g. with tetrafluoroethylene and heated to 700C. Tetraf- luoroethylene pressure was maintained at 200 p.s.i.g. for 45 min at 70 C. The polymeric product thus obtained was filtered, washed and dried to give 43.2 g of white solid which contained approximately 1.4 wt Ci. (0.43 mol %) of polyfluoroallyloxy comonomer by infrared analysis. Differential thermal analysis (DTA) showed a crystalline transition at 10 C, a recycle freezing temperature of 293 C and a recycle melting point of 311 C from which the polyfluor point depression was 91 C compared with polytetrafluoroethylene. Sulfur analysis by x-ray fluorescence gave 2.7% S or 28.0 wl. % (8.5 mol %) of polyfluoroallyloxy comonomer, corresponding lo an equivalent weight of 1180.

'l'he product was pressed into a clear 4-5 mil film at 220-24()0C. Four inch diameter film samples were reacted for 1 hour at 90 C with 13-15% potassium hydroxide solution and dried to give a copolymer of 'l'FE and CF2=CFCF2OCF2CF2SO3 K+. IR spectra showed essentially complete conversion of -SO2F functions to sulfonate salt.

The four-inch diameter, 4-5 mil film was inserted as the ion exchange membrane in a chlor-alkali electrolysis cell operated at 2.0 amps/in. Cell voltage and current efficiency wcre measured as a function of cell operating time and sodium hydroxide concentration.

The following rcsults were obtained for a 1 5-day test: Sodium Hydroxide Current Efficiency Cell Voltage Day Product (%) (%) (volts) 21.5 70.7 3.35 10 21.5 71.2 3.45 15 30.0 65.2 3.60 UTILITY EXAMPLE R Copolymerization of Tetrafluoroethylene and Perfluoro-6-oxanon-8-enoic acid, and Preparation of Electrically Conductive Films from the Copolymer Product

The procedure of Example Q was followed with perfluoro-6-oxanon-8-enoic acid (47.5 g), 8% pentafluoropropionyl peroxide in 1,1,2-trichloro-1,2,2-trifluoroethane (0.05 g), and i'Fl: at 10 psig (40 C) to give 2.41 g of solid, white copolymer: DSC melting point depression was 157 C compared with polytetrafluoroethylene. Analysis of carboxyl groups by titration showed 36.8 wt. % (9.3 mol % of polyfluoroallyloxy comonomer, corresponding to an equivalent weight of 1070.

The copolymer product wis pressed into 4-5 mil film and hydrolyzed as described in Example Q. IR spectra showed essentially complete conversion of -COF functions to carboxylate salt, indicating a copolymer of TFE and CF2=CFCF2O(CF2)4CO2-K+.

Claims (26)

A four-inch diameter sample of the 4-5 mil film was inserted as the ion-exchange membrane in a chlor-alkali cell operated at 2.0 amps/in, and the following results were obtained in a 76 day test: Sodium Hydroxide Current Efficiency Cell Voltage Day Product (%) (%) (volts)

1 37.1 93.3 4.02

20 39.2 90.9 4.60

35 39.4 - 87.7 4.25

50 32.9 92.0 4.11

76 34.6 85.8 4.67 WHAT WE CLAIM IS: I. A polyfluoroallyloxy compound having the general formula:

wherein X is -Cl or -F; W and Z independently are -F or together are -CF2-; D independently is -F.

or -RF2 where -RF is a linear or branched perfluoroalkyl of 1 to 10 carbon atoms, interruptable no more frequently than every second carbon atom by from 1 to 4 oxygen atoms, having 0 to 2 functional groups selected from -SO2F, -COF, -CO2H, -CO2R , -Cl, -OCF2CF=CF2 and -OCF2CO2R , where R is -CH3 or -C2H5; E independently is -F, -CF3, -CF2Cl, -CF2CO2R , where R3 is as defined herein, or -ROCF(G)2; or D and E together form a 5- or 6- membered ring whose members are RF-, where RF is a perfluoroalkylene chain of 4 or 5 members, interruptable by one or two oxygen atoms, and having 0 to 2 substituent -CF3 groups, or

G is -F or -CF3.

2. A compound according to claim 1 wherein D is -F or -RF and E is -F, -CF3, -CF2Cl or -CF2CO2R .

3. A compound according to claim 1 or 2 wherein RF is a linear or branched perfluoroalkyl of 1 to 8 carbon atoms, interruptable with no more than 1 oxygen atom, having 0 or 1 functional group selected from -SO2F, -COF, -Cl, -CO2H, -CO2R3, -OCF2CF=CF2 and -OCF2CO2R , where R is -CH3 or -C2H5.

4. A compound according to claim 1, 2 or 3 wherein - R2F is -CF2OCF2COF.

5. A compound according to claim 1 wherein D is -CF2R4 or

where R4 is -F, -SO2F, -COF, -CO2H, or (-CF2)xR@ where X is 1 to 6 and R5 is -CF3, -OCUCF=CF2, -COF, -CO2CH3 or -SO2F; E is -F, -CF3 or -CF2Cl; G is -F; and W and Z independently are -F.

6. A compound according to claim 5 wherein R5 is -CF3 or -OCF2CF=CF2.

7. A compound according to claim 6 wherein X is -F, D is -CUR4, E is -F and R4 is -SO2F.

8. A polyfluoroallyloxy compound having the general formula:

wherein X is -Cl or -F: D is -CUR4 or

where R4 is -F, -SO2F, -COF, -CO2H, -CO2R , -OCF2CO2R , or (CF2)xR where R3 is -CR3 or -C2H5, x is 1 to 6 and R5 is -CF3 or -OCF2CF=CF2; and E is -F, -CF3 or -CF2CO2R where R3 is as defined herein.

9. A compound according to claim 1 substantially as described in any one of Examples 1 to 22.

10. A process for preparing a polyfluoroallyloxy compound which process comprises: (1) mixing and reacting a carbonyl compound of the general formula:

wherein A is -F. -COCF3 or -RF where RF is a linear or branched perfluoroalkyl of 1 to 10 carbon atoms. interruptable no more frequently than every second carbon atom by from 1 to 4 oxygen atoms, having 0 to 2 functional groups selected from -SO2F, -SO2OCF2CH3, COF, -Cl, -OCF2CF=CF2 and -CO2R , where R@ is -CH3 or -C2H5, B is -F, -CF3, -CF2Cl, -CF2CO2R , where R is as defined herein, or -CF2ORF where RF is as defined herein. or A and 13 together f)nli a 5- or 6- membered ring whose members ale -RF- where RF is a perfluoroalkylene chain of 4 or 5 members, interruptable by one or two oxygen atoms; and having () to 2 substituent trifluoromethyl groups; with a fluoride of the formula MF where M is K-, Rb-, Cs-, or R4N- where each -R, alike or different. is alkyl of I to 6 carbon atoms; and (2) mixing the mixture from (1) with a polyfluoroallyl compound of the general formula:

wherein X is -Cl or -F; W and Z independently are -F or together are -CF2-; and Y is -Cl or -OSO2F.

11. A process according to claim 1() wherein W and Z are -F, X is -F, and Y is -OSO2F.

12. A process according to claim 10 or 11 wherein steps (1) and (2) are conducted in an anhydrous aprotic polar solvent.

13. A process according to claim 12 wherein the solvent is N,N-dimethylformamide, diglyme, triglyme or acetonitrile.

14. A process according to any one of claims 10 to 12 wherein step (1) is carried out at a temperature of from -20 to +6() C and step (2) is carried out at a temperature of from -20 to +80 C.

15. A process according to claim 14 wherein step (1) is carried out at a temperature of from 0 to 10 C and step (2) is carried out at a temperature of from 0 to 30 C.

16. A process according to claim 10 substantially as described in any one of Examples 1 to 22.

17. A polyfluoroallyloxy compound when prepared by a process as claimed in any one of claims 10 to 16.

18. A copolymer of a polyfluoroallyloxy compound as claimed in any one of claims 1 to 9 and 17 and at least one ethylenically unsaturated monomer.

19. A copolymer according to claim 18 wherein the ethylenically unsaturated monomer is an olefin. halogenated olefine trifluoromethyl trifluorovinyl ether, acrylic acid ester or methacrylic acid ester.

20. A copolymer according to claim 19 wherein the ethylenically unsaturated monomer is vinylidene fluoride. chlorotrifluoroethylene, trifluoromethyl trifluorovinyl ether, tetrafluoroethylene or hexafluoropropylene.

21. A copolymer according to claim 18, 19 or 20 wherein the polyfluoroallyloxy compound content is from 0.1 to 55 percent by weight of the copolymer.

22. A copolymer according to claim 21 wherein the polyfluoroallyloxy compound content is from 1 to 10 percent by weight of the copolymer.

'3. A copolymer according to claim 18 substantially as described in any one of Examples A to R.

24. An electrically conductive membrane formed of a hydrolyzed or ionized copolymer as claimed in any one of claims 18 to 23 derived from a polyfluoroallyloxy compound containing at least one functional group selected from -COF, -CO2H, -CO2H, -CO2R3, -SO2F, -OCF2CO2R3 and -CUCO2R3, wherein R3 is methyl or ethyl.

25. A chlor-alkali electrolytic cell comprising a membrane as claimed in claim 24 between anode and cathode.

26. A process of producing an alkali metal hydroxide which comprises electrolysing an aqueous solution of an alkali metal chloride in a chlor-alkali cell as claimed in claim 25.