Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C43/00—Ethers; Compounds having groups, groups or groups
  • C07C43/02—Ethers
  • C07C43/03—Ethers having all ether-oxygen atoms bound to acyclic carbon atoms
  • C07C43/04—Saturated ethers
  • C07C43/12—Saturated ethers containing halogen
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C43/00—Ethers; Compounds having groups, groups or groups
  • C07C43/30—Compounds having groups
  • C07C43/313—Compounds having groups containing halogen
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
  • C07C41/48—Preparation of compounds having groups
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
  • C07C41/60—Preparation of compounds having groups or groups
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C43/00—Ethers; Compounds having groups, groups or groups
  • C07C43/30—Compounds having groups
  • C07C43/315—Compounds having groups containing oxygen atoms singly bound to carbon atoms not being acetal carbon atoms
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G2/00—Addition polymers of aldehydes or cyclic oligomers thereof or of ketones; Addition copolymers thereof with less than 50 molar percent of other substances
  • C08G2/30—Chemical modification by after-treatment
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G4/00—Condensation polymers of aldehydes or ketones with polyalcohols; Addition polymers of heterocyclic oxygen compounds containing in the ring at least once the grouping —O—C—O—
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
  • C08G65/002—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from unsaturated compounds
  • C08G65/005—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from unsaturated compounds containing halogens
  • C08G65/007—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from unsaturated compounds containing halogens containing fluorine
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
  • C08G65/02—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring
  • C08G65/30—Post-polymerisation treatment, e.g. recovery, purification, drying
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
  • C08G65/02—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring
  • C08G65/32—Polymers modified by chemical after-treatment
  • C08G65/321—Polymers modified by chemical after-treatment with inorganic compounds
  • C08G65/323—Polymers modified by chemical after-treatment with inorganic compounds containing halogens
  • C08G65/3233—Molecular halogen
  • C08G65/3236—Fluorine
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
  • C08G65/34—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from hydroxy compounds or their metallic derivatives
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
  • C08G65/34—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from hydroxy compounds or their metallic derivatives
  • C08G65/46—Post-polymerisation treatment, e.g. recovery, purification, drying

Definitions

• This invention relates to perfluoroacetals and perfluoroketals, their preparation, and to their use as liquid heat transfer media, e.g. in inducing a thermal shock to an article, such as an electronic component or device, for test purposes.
• Thermal shock testing is used to determine the effect, if any, of rapid and extreme temperature changes on electronic components, for example those used in aircraft which in seconds must be able to ascend from desert heat into stratospheric sub-zero cold. This testing is a type of quality control screening or
• the electronic component to be tested is alternately heated far above ambient temperature and cooled far below ambient temperature to induce a thermal shock and then visually inspected and/or
• testing liquids generally have been required, one being a heating liquid with a boiling point in excess of the temperature of the heating bath and one being a cooling liquid with a low viscosity at the temperature of the cooling bath.
• a perfluorinated liquid composition FLUORINERT Electronic Liquid FC-40, having a boiling point at about 155°C, has approval as the heating liquid for thermal shock testing up to 150°C
• a perfluorinated liquid composition, FLUORINERT Electronic Liquid FC-77 having a boiling point of about 97°C and a low viscosity at -65°C, has approval as the cooling liquid.
• a liquid mixture of perfluoropolyethers sold under the trademark GALDEN has been described as useful as a single thermal shock liquid, i.e. a liquid used for both the heating and cooling baths.
• the GALDEN R fluids are described in a trade bulletin of Montedison S.p.A. on "GALDEN R PERFLUORINATED FLUIDS" as a mixture of linear low molecular weight polymers said to have the structure
• DO2TS perfluorinated fluid sold as DO2TS has been found to have a boiling point of 165°C and viscosities of 231
• Measures can be taken to narrow the molecular weight distribution of th olyether mixture prior to use as a single thermal shock fluid, e.g. by control of the
• perfluoroacetals those copolymers being mixtures of a plurality of molecular species of perfluoropolyethers with a broad range of molecular weights, some of the species having a random internal structure and all of the species having inert terminal groups, viz., random distribution of methyl or ethyl.
• this invention provides a perfluorinated gem-alkylenedioxy composition which can be normally liquid and which consist or consist essentially of one or a mixture of perfluorinated gem-alkylenedioxy compounds, viz., perfluoroacetal or perfluoroketal
• perfluoropoly(alkyleneoxy)alkyl wherein one or more but preferably not all of the fluorine atoms may be halogen atoms other than fluorine, e.g. chlorine; wherein R 1 and R 2 are the same or different and are selected from the group consisting of -F, -Cl, -CF 2 Cl, -CFCl 2 , -CCl 3 , and perfluoroalkyl of 1 to 10 carbon atoms wherein one or more of the fluorine atoms but preferably not all may be halogen atoms other than fluorine, e.g., chlorine an wherein the perfluoroalkyl group may contain one or more ether oxygen atoms.
• the polyether of formula I may be an atactic or isotactic polymer or a block copolymer each having up to 50 carbon atoms; examples of such polyethers are Y-O-CF 2 -OY and Y-O-CF(CF 3 )-O-Y wherein each Y is the same, i.e., the same perfluoropoly(alkyleneoxy)alkyl group.
• Formula I can be considered as embracing two types of fluorinated ethers: (1) perfluoroacetals, when one of R 1 and R 2 is a halogen, e.g. fluorine (a subclass of fluorine).
• perfluoroacetals being perfluoroformals, when both R 1 and R 2 are halogen, e.g. fluorine); and (2) perfluoroketals, when both of R 1 and R 2 are o er than halogen, viz., perhaloalkyl, which can contain oxygen.
• R 2 is a group other than -CF 3 or -CF 2 Cl.
• this invention provides a normally liquid, perfluoroacetal composition which is useful, for example, as a thermal shock testing fluid.
• composition can consist or consist essentially of a saturated perfluoro-1,1-bis(alkyloxy)alkane compound as the single molecular species in the composition (and such composition is hereafter on occasion referred to for brevity as a "single molecular perfluoroacetal
• composition or "unimolecular” composition or fluid).
• Said compound (hereafter referred to on occasion as a perfluoroacetal compound) thus has a
• this invention provides a normally liquid, perfluoroacetal composition which consists or consists essentially of a mixture of two or more such compounds (and such
• composition is hereafter referred to on occasion for brevity as a "mixed perfluoroacetal composition" of discrete, non-random molecular weights, said compounds preferably being those having complementary properties, for example, boiling points and pour points each within respective narrow ranges, desired for a particular use of the composition, e.g. for use as a heat exchange medium.
• mixed perfluoroacetal composition of discrete, non-random molecular weights, said compounds preferably being those having complementary properties, for example, boiling points and pour points each within respective narrow ranges, desired for a particular use of the composition, e.g. for use as a heat exchange medium.
• perfluoroacetal composition as used herein means that consisting or consisting essentially of one or a mixture of said compounds, that is, the term is used in a generic sense to cover the single molecular and the mixed
• the perfluoroacetal compound can have one or a few, e.g. 2 or 3, chlorine atoms, each of which is bonded to carbon atoms other than those carbon atoms to which an ether oxygen atom is bonded; stated otherwise, the
• compound can have 1, 2, or 3 carbon-bonded chlorine atoms in place of 1, 2 or 3 carbon-bonded fluorine atoms of the alkyloxy moieties if the carbon atoms to which the
• chlorine atoms are bonded are other than those to which the ether oxygen atoms are bonded.
• the perfluoroacetal composition which is liquid at ambient conditions, e.g. 20°C at 740 Torr, generally has a boiling point greater than 20°C, preferably a boiling point of at least 40°C, and more preferably a boiling point greater than 125°C, e.g. 180°C, and can have a boiling point as high as 300°C. Generally the.
• perfluoroacetal compound has at least 6 carbon atoms, and can have as many as 24 carbon atoms or even up to 30 carbon atoms, but preferably the compound has at least 12 carbon atoms, e.g. 12 to 17 carbon atoms.
• perfluoroacetal compound is a chlorine-containing compound
• perfluoroacetal compound its effect on the boiling point of the perfluoroacetal composition will be approximately the same as that of a perfluoroacetal compound which does not contain chlorine atoms and has a higher carbon
• chlorine atom will have about the same effect on boiling point as 1.5 to 2 carbon atoms.
• a particularly useful property of the perfluoroacetal composition of this invention is its wide liquid range, meaning it is normally liquid over a wide temperature range; in fact, some of them can be considered as having exceptionally wide liquid ranges.
• a feature of the perfluoroacetal compositions of this invention is that the perfluoroacetal compound or compounds thereof are each of well-defined, definite, certain, and known structure of a non-random nature and with fixed carbon, fluorine, and oxygen ratios and of a definite (or particular or
• structures and amounts of each compound in the mixture are features which can be completely predetermined and the mixture made by mixing or blending selected single
• perfluoroacetal compositions of this invention is a feature which means that their physical properties, particularly their low temperature viscosity and their discrete boiling point, are invariable under conditions of use, for example where in use as a thermal shock fluid some of such single molecular weight perfluoroacetal composition is lost through volatilization. Some of the mixed perfluoroacetal compositions can have these
• perfluoroacetal compounds in the mixture are judiciously selected, for example by empirically selecting those with the desired boiling points and low temperature viscosities.
• the perfluoroacetal compositions also have utility as hydraulic fluids, as pump fluids for corrosive environments, and as fluids for vapor-phase condensation heating for soldering and polymer-curing applications.
• Their low temperature viscosities are especially low compared with the viscosities of prior art perfluorinated polyether fluids which have a distribution of molecular weights and compositions.
• viscosities render the perfluoroacetal compositions of this invention especially effective, particularly in comparison with the prior art fluids, as heat transfer media at low temperatures.
• perfluoroacetal and perfluoroketal compositions are prepared by direct fluorination of their
• perfluorinateable, saturated or unsaturated acetal or ketal precursors which can be fluorine-free or
• Perfluorinateable means the acetal or ketal precursor contains carbon-bonded hydrogen atoms which are replaceable with fluorine and any carbon-carbon unsaturation in the precursor can be saturated with fluorine.
• perfluoroketal compounds can be made with the same number and spatial arrangement of carbon atoms as the precursors thereof.
• the fluorination can be carried out at a
• a transparent window is needed which does not react with either fluorine or hydrogen fluoride.
• a quartz lens coated with a thin film of fluorinated ethylene-propylene copolymer works well.
• the fluorination is preferably carried out in an oxygen- and water-free environment and can be carried out in the presence of solid, particulate scavenger, such as sodium fluoride, for the hydrogen fluoride by-product generated.
• the fluorination can be carried out in an inert liquid, such as a fluorocarbon or chlorofluorocarbon liquid, as a reaction medium, or carried out with the use of both the scavenger and the inert liquid.
• fluorination is preferably carried out by using fluorine diluted with inert gas to directly perfluorinate precursor acetal in the inert liquid (and, for operational
• a class of perfluoroacetal compositions of this invention is that whose members consist or consist
• C 1 to C 8 preferably C 1 to C 6 , linear or branched perfluoroalkyl, C 1 to C 8 , preferably C 1 to C 6 , linear or branched chloroperfluoroalkyl, and unsubstituted or lower alkyl-substituted
• each f is independently a fluorine atom or perfluoroalkyl with 1 to 4 carbon atoms, and is preferably perfluoromethyl or, more preferably a fluorine atom;
• x and w are each independently an integer of 0 to 4;
• y is an integer of 1 to 6,
• z is an integer of 0 or 1; and the total number of carbon atoms in said compound can be 6 to 30, preferably at least 12, e.g. 12 to 17, and more preferably 13 to 14 because of the extremely low viscosity at low temperatures, e.g. less than about 300 centistokes at -70oC, coupled with high boiling point, e.g. above about 175°C, that the compositions have when the total carbon atoms are 13 or 14.
• chloroperfluoro- is used herein to describe a perfluoro moiety in which 1 or 2 fluorine atoms are replaced in a sense by chlorine atoms, e.g.
• the perfluoroacetal compositions preferably have a boiling point in the range of 160°C to 250°C, and more preferably in the range of 175°C to 200°C.
• the perfluoroacetal compounds of this invention contain at least one perfluoro-1,1-alkylenedioxy unit, e.g. -OCF )O- in formula II, which can be located
• a perfluoroacetal compound can contain two perfluoro-1,1-alkylenedioxy units separated by at least two catenary carbon atoms of a perfluoroalkylene moiety and each of the units located at approximately the center of a different molecular half of the compound.
• “approximately at the center” means having about the same number, plus or minus about one, of perfluoroalkyleneoxy units on each side of the molecule (in the case of a single alkylenedioxy unit) or molecular half (in the case of two such units).
• a particularly useful subclass of the perfluoroacetal compositions of this invention is that whose members consist or consist essentially of one or a mixture of two or more perfluoroacetal compounds falling within the following representational general formula:
• each n and n' is independently an integer of 1 to 6
• each m and m' is independently an integer of 2 to 4
• a and b are each independently an integer of 0 to 4
• p is 0 or 1 (if p is 0 then the central moiety is -OCF 2 O- and if it is 1 then the central moiety is -OCF(CF 3 )O-)
• each said compound preferably having 13 to 14 total carbon atoms, said composition having a viscosity at -70°C of less than about 300 centistokes, preferably less than about 200 centistokes.
• this invention also provides a method of transferring heat from an article, such as an electronic component or device, to a cooling liquid, the method comprising directly contacting the article with an above-described perfluoroacetal composition of this
• This invention further provides a method of inducing a thermal shock to an article, such as an electronic
• the method comprising the following steps: a) heating a first bath of a heating liquid to a
• liquids are inert, thermally stable
• perfluorinated liquids at least one of which is, but
• a perfluoroacetal composition of this invention preferably both are, a perfluoroacetal composition of this invention, more preferably the version which is a single molecular perfluoroacetal composition.
• the single molecular perfluoroacetal composition of this invention which is essentially a single perfluoroacetal compound, does not have these disadvantages of prior art fluids (which have a distribution of molecular weights).
• the version of the perfluoroacetal composition of this invention which is a mixture of perfluoroacetal compounds also can overcome these disadvantages if each of the compounds in the mixture have the same or about the same boiling point, e.g. boiling points within a 10 to 15°C range, and viscosity, e.g. viscosities at -70°C of up to 300 cs, necessary to maintain the desired bath temperatures.
• the perfluoroacetal compositions and perfluoroketal compositions of this invention may be prepared from their hydrogen-containing, saturated or unsaturated,
• non-fluorinated or partially-fluorinated, non-chlorinated or partially-chlorinated hydrocarbon analog acetals and ketals which are perfluorinateable by direct fluorination.
• the perfluorinated products may contain small amounts of fluorinated materials having one or a f idual hydrogen atoms
• the perfluoroacetal and perfluoroketal compositions of this invention are, except for any chlorine content
• This residual hydrogen content can be lowered or essentially completely removed (as well as traces of undesired carboxyl ic acid derivatives such as terminal acyl fluoride groups resulting presumably from chain degradation reactions) upon treating at elevated temperature, e.g. at 150°C or higher, e.g. 175°C or even 260°C, the fluorinated product with fluorine, for example fluorine diluted with an inert gas such as nitrogen, such treatment being referred to hereinafter on occasion as the "polishing" finishing technique.
• the precursor acetal or ketal starting material is contacted with fluorine diluted with an inert gas, such as helium or, preferably, nitrogen, at low initial concentrations of fluorine of about 5 to 25 volume %, preferably about 10 to 15 volume %, and at low initial temperature, which is preferably -20°C to 0°C.
• an inert gas such as helium or, preferably, nitrogen
• the precursor is fluorinated in the presence of a hydrogen fluoride scavenger, such as
• the scavenger may be in particulate form such as pellets or, preferably, powder.
• Such a perfluorination technique is described in U. S. Patent 4,755,567 (Bierschenk et al.), which description is incorporated herein by reference.
• perfluorination process is scavenged.
• enger precursor weight ratios of from about 1:1 to ab 1 have been found useful in fluorinating the precursor acetals or ketals.
• the precursor may be mixed with or coated on the scavenger and the mixture fluorinated in a
• fluorination apparatus such as a stationary metal tube reactor, a rotating drum reactor, or a fluidized bed reactor, this technique generally giving yields of about 15 to 30 mol % of the desired perfluoroacetal or perfluoroketal
• perfluoroacetal and perfluoroketal compositions of this invention involves making a very dilute dispersion, emulsion, or, preferably, solution of the precursor acetal(s) or ketal(s) in a liquid reaction medium, which is relatively inert to fluorine at the fluorination temperatures used, the concentration of the starting material thus being relatively low so as to more easily control the reaction temperature.
• the reaction mixture can also contain or have dispersed therein a sufficient quantity of hydrogen fluoride scavenger such as sodium fluoride or potassium fluoride to complex with all of the hydrogen fluoride formed.
• the scavenger :precursor weight ratio can be, for example, from about 0.5:1 to 7:1.
• the reaction mixture can be vigorously agitated while the fluorine gas is bubbled through it, the fluorine preferably being used in admixture with an inert gas, such as nitrogen, at a concentration of about 5 to 50 volume %, more preferably about 10 to 25 volume %, and being maintained in
• stoichiometric excess throughout the fluorination e.g. up to 15 to 40%, or higher, depending on the particular starting material and the efficiency of the equipment used, such as the stirrer. Yields generally in the range of about 30-77 mol %, and, with experience, as high as 65 to about 80 mol %, of the perfluoroacetal or perfluoroketal product may be achieved by this method.
• Suitable liquids useful as reaction media are chlorofluorocarbons such as FreonTM 113,
• polyepichlorohydrin liquids which media generally will function as good solvents for non-fluorinated precursors
• FluorinertTM electronic liquids FC-75, FC-72, and FC-40 FluorinertTM electronic liquids FC-75, FC-72, and FC-40, perfluoroalkanes such as perfluoropentane and
• perfluorodecalin perfluoropolyethers such as KrytoxTM and FomblinTM
• perfluoroalkanesulfonyl fluorides such as
• perfluorobutanesulfonyl fluoride and the perfluoroacetal compositions of this invention, and this latter group of media, i.e., perfluoroalkanes, etc.
• this latter group of media i.e., perfluoroalkanes, etc.
• Mixtures of such liquids can be used, e.g. to get good dispersion of precursor and intermediate reaction products.
• the reaction media are conveniently used at atmospheric pressure. Lower molecular weight members of the above classes of reaction media can also be used, but elevated pressures are then required to provide a liquid phase.
• the fluorination reaction is
• a temperature between about -10°C to +50°C, preferably between about -10°C to 0°C if a hydrogen fluoride scavenger is used, and if such scavenger is not used, between about 0°C to 150°C, preferably about 0°C to 50°C, most preferably about 10°C to 30°C, the temperature being sufficient to volatilize the hydrogen fluoride
• the reaction medium and other organic substances may to some extent be present in the gaseous reactor effluent, and a condenser may be used to condense the gaseous reaction medium and such substances in the effluent and permit the condensate to return reactor.
• the condenser should be operated so as to minimize or prevent the return to the reactor of hydrogen fluoride by-product (which would have an adverse effect on yield of perfluorinated product if allowed to remain in the reactor during
• the return of the hydrogen fluoride can be minimized or prevented by selective condensation of the organic materials while allowing the hydrogen fluoride to pass through the condenser, or by total condensation into a separate vessel of both hydrogen fluoride and the organic materials followed, if desired, by separation of the hydrogen fluoride as the upper liquid phase and the return of the lower liquid phase.
• the reaction may be carried out in a batch mode, in which all of the precursor is added to the liquid prior to fluorination to provide a precursor
• the reaction can also be carried out in a semi-continuous mode, in which the precursor is continuously pumped or otherwise fed neat, or as a diluted solution or dispersion or emulsion in a suitable liquid of the type used as a reaction medium, into the reactor, e.g. at a rate of about 1 to 3 g/hr into 400 mL of liquid reaction mixture, as fluorine is bubbled through, e.g. at a fluorine flow rate of about 40 to 120 mL/min and an inert gas flow rate of about 150 to 600 mL/min.
• the fluorination can also be carried out in a continuous manner: the precursor (either neat or dissolved or dispersed in a suitable liquid of the type used as a reaction medium to form a solution or
• fluorine-containing gas is introduced, as described above, and the stream of unreacted fluorine, hydrogen fluoride gas, and inert carrier gas being continuously removed from the reactor as is a stream of liquid comprising perfluorinated product, incompletely fluorinated precursor, and inert liquid reaction medium, and the necessary separations being made to recover the perfluoroacetal composition, and, if desired, with recycling of the unreacted fluorin d the incompletely fluorinated precursor.
• an alternative method for fluorinating the precursors which are insoluble in the liquid fluorination medium involves adding a solvent to the precursor which allows limited solubility of precursor in the liquid fluorination medium.
• a solvent for clarity of illustration, 1,1,2-trichlorotrifluoroethane has been selected as the liquid fluorination medium; however, other highly fluorinated solvents can also be used.
• 1,1,2-trichlorotrifluoroethane will give a homogeneous solution.
• a solvent is selected which readily dissolves the precursor. Often it is possible to choose a solvent which will consume little, if any, of the fluorine gas.
• Trifluoroacetic anhydride Trifluoroacetic acid, chloroform, 1,1,2-trichloroethylene and 1,1,2-trichloroethane work especially well.
• the fluorination reactor As the precursor solution contacts the 1,1,2-trichlorotrifluoroethane in the reactor, an emulsion is formed.
• the resulting precursor droplets are in most cases sufficiently small that they react quickly with the fluorine gas with negligible side reactions.
• the amount of inert liquid medium in the reactor can be maintained at a constant level by addition of recycled or fresh liquid.
• perfluorinated product from the batch mode generally will have significant residual hydrogen, e.g. about 7 mg/g, whereas the perfluorinated product made by the continuous or semi-continuous mode will generally have less residual hydrogen, e.g. less than 0.1 mg/g.
• the perfluorinated product made by the continuous or semi-continuous mode will generally have less residual hydrogen, e.g. less than 0.1 mg/g.
• the reactor is purged of fluorine and the reactor contents are removed.
• the reactor contents can be mixed with Freon 113 or Fluorinert FC-72 solvent, the resulting slurry filtered, and the solvent stripped, e.g. by vacuum distillation, to provide crude perfluorinated product.
• the fluorination is carried out by the liquids
• the spent scavenger in the presence of a hydrogen fluoride scavenger, can be separated by filtration or decantation from the liquid reactor contents and the latter then distilled to separate the reaction medium from the crude perfluorinated product.
• the reaction product mixture can be distilled to recover the perfluorinated product.
• the crude perfluorinated product can be treated with a base, e.g. sodium hydroxide, to remove acid and hydride impurities or treated, e.g. at a temperature above 150°C, by the polishing finishing technique to remove hydrogen and acid impurities and the so-treated product distilled.
• a base e.g. sodium hydroxide
• the order of these purification steps can be varied to obtain best results.
• the precursor acetals used for preparation of the perfluoroacetal compositions of this invention can be any suitable acetals used for preparation of the perfluoroacetal compositions of this invention.
• Lower acetals can be converted to higher ones by heating with the higher alcohol under acid catalysis, as
• a mixture of NaOH, or preferably KOH, and the alcohol displacees chloride from methylene chloride.
• Equation 6 Another route to asymmetric acetal is the reaction of a vinyl alkyl ether with an alcohol under acid catalysis, as illustrated in Equation 6.
• Equations 1-3 can be used for preparing those precursors with two of such units, although yields are lower due to competing
• mixtures of alcohols, aldehydes, and/or acetals can be used as reactants to prepare mixtures of precursors that are fluorinated to make perfluoroacetal compositions of this invention which are mixtures of perfluoroacetal
• Equation 1 the process of Equation 1 can be modified by use of two different alcohols, as illustrated in
• diethylene glycol butyl ether triethylene glycol methyl ether, triethylene glycol ethyl ether, triethylene glycol butyl ether, tetraethylene glycol methyl ether.
• tripropylene glycol butyl ether tripropylene glycol butyl ether
• Useful precursor acetals for conversion by direct fluorination to the perfluoroacetals of this invention include each of those in the following list of materials and mixtures of 2, 3, or more thereof:
• perfluoroacetal compounds of this invention include the perfluorinated counterparts of the precursor acetals listed above. Where the precursors have unsaturation, the corresponding perfluoroacetals thereof are saturated.
• the perfluoroacetal compositions of this invention generally have surprisingly low viscosities at low
• a preferred utility for the perfluoroacetal compositions of this invention is in cooling an article to a temperature below ambient, e.g., a temperature far below ambient temperature, such as -65°C. Such cooling may take place as part of a thermal shock method which can be used to temper or test a material.
• An especially preferred utility is use in the thermal shock method of this invention, which is preferably carried out in accordance with Condition B or C of U.S. Military
• thermal shock method may also be carried out using two thermal shock liquids, one being a conventional electronic testing fluorochemical liquid which may be used in either of the two baths, and the other being a perfluoroacetal
• composition of this invention which is used in the
• suitable conventional liquids include the inert, perfluorinated organic compounds available from 3M as FLUORINERT TM Electronic Liquids described in product bulletin No. 98-0211-2267-0 (161 )NPI issued February 1986.
• the thermal shock method of this invention using a single thermal shock liquid can be carried out, for example, as follows in accordance with MIL-STD-883-1011.6, Condition C.
• the article such as an electronic component or device to be tested, can be preconditioned by being immersed in a heated bath of a perfluoroacetal composition of this invention at an elevated temperature between 150°C and 160°C for a minimum of 5 minutes.
• the article is transferred to a cooled bath of the perfluoroacetal composition at a temperature between about -65°C and
• the article is held at the low temperature for 5 minutes, at the end of which time it must itself reach -65°C, and it is then transferred back to the heated bath of the perfluoroacetal composition.
• the article remains at the high temperature for 5 minutes. Transfer time from the high temperature bath to the low temperature bath and from the low temperature bath to the high temperature bath is less than 10 seconds.
• the duration of the test is generally about 15 complete cycles, where one cycle consists of immersion in and removal from the heated bath of the perfluoroacetal composition and immersion in and removal of the article from the cooled bath of the
• thermal shock test After completion of the final cycle of a thermal shock test, an external visual examination of the article is generally performed without magnification or with a magnifying viewer. Typical effects of thermal shock on defective articles include cracking and delamination of substrates or wafers, opening of terminal seals and case seams, and changes in
• the electronic performance of the electronic components can be determined and compared with the electronic performance of the article prior to thermal shock testing.
• perfluoroacetal composition of this invention can be placed in the heating bath of a thermal shock apparatus and a different perfluorinated, inert liquid, such as a conventional, perfluorinated, inert thermal shock testing liquid, e.g., FLUORINERT FC-77, is placed in the cooling bath.
• a conventional, perfluorinated, inert thermal shock testing liquid e.g., FLUORINERT FC-77
• perfluoroacetal composition when carried over into the cooling bath, will generally not raise the viscosity of the cooling bath to the extent that a conventional thermal shock heating liquid, e.g., FLUORINERT FC-40, does over extended use.
• a conventional thermal shock heating liquid e.g., FLUORINERT FC-40
• perfluoroacetal composition of this invention can be placed in the cooling bath of a thermal shock apparatus and a different perfluorinated, inert liquid, such as a conventional, perfluorinated, inert, thermal shock testing liquid, e.g., FLUORINERT FC-40, is placed in the heating bath.
• a conventional, perfluorinated, inert, thermal shock testing liquid e.g., FLUORINERT FC-40
• the manipulative steps and conditions used can be the same as those described above for the single thermal shock method.
• the perfluoroacetal composition of this invention when carried over into the heating bath, will generally not volatilize from the heating bath to the extent that a conventional thermal shock cooling liquid, e.g. FLUORINERT FC-77, does over extended use.
• the methods of this invention of inducing a thermal shock can be applied to almost any article which is immersible in the baths used in the method, the methods are preferably used to induce a thermal shock in an electronic device or component to evaluate the electronic component's response to the thermal shock.
• electronic components and devices include integrated circuits, integrated circuit assemblies, micro-electronic components and devices, ceramic and plastic carriers for electronic chips, and assemblies of micro-electronic components, e.g., integrated circuits, transistors, diodes, resistors, capacitors, and the like.
• Apparatus suitable for performing a thermal shock test are available from many manufacturers, e.g., Blue M Engineering, Blue Island, IL; Cincinnati Sub-zero
• the perfluoroacetal compositions of this invention can also be as additives for other inert fluorochemical liquids, used, for example, as thermal shock fluids, hydraulic fluids, heat exchange media, and other working fluids, to modify or adjust their viscosities or pour points.
• thermometer in a sample of distilled liquid product contained in a glass vial and then placing the vial in a liquid nitrogen or dry ice bath to cool the sample to a solid, glassy state. The vial was then allowed to warm slowly and the temperature at which complete fluidity was attained was noted and recorded as the pour point.
• the viscosity in these examples was measured by conventional means using a Wescan viscometer timer and Cannon-Fenske viscometer tubes, as described in ASTM D446-74 (reapproved in 1979). Stable low temperatures for the viscosity measurements were achieved using Fluorinert FC-75 as the bath medium; the temperature of the perfluoroacetal composition was measured with a resident thermocouple.
• a cylindrical brass reactor (about 7.5 cm in diameter and about 30 cm long, with a sealed bottom and a removable head) was fitted with a copper tube through the head reaching to within about 5 cm of the bottom as the gas inlet and a hole in the head was fitted as the exit.
• Example 7 using methylene chloride as a source of the formal moiety
• 210 g (5.0 mol) NaF powder was placed in the reactor, which was then installed horizontally in a water-ethylene glycol bath and rotated at about 20-30 rpm. Fluorine and nitrogen were mixed prior to entry. The bath was cooled to -17°C and the gas mixture of 60 mL/min fluorine and 240 mL/min nitrogen was begun. An exotherm of abouat 2 to 5°C was registered by an internal thermocouple. After 22 hr, the exotherm was ⁇ 1°C and the temperature was increased by 10-15°C
• Example 7 three perfluoroacetal compositions were made: Ex. 2, perfluoro-bis ( cyclohexyloxy)methane, having a boiling range of 105-130°C/60 Torr and a pour point of -45°C, was prepared from bis(1,1-cyclohexyloxy)methane: Ex. 3, perfluoro-bis(2,4-dichlorocyclohexyloxy)methane, having a boiling point of 150° C/40 Torr and a pour point of -25°C, was prepared from bis(2,4-dichlorophenoxy)- methane: and Ex.
• Perfluoro-bis(isooctyloxy)methane having a boiling range of 120-140°C/60 Torr and a pour point of -40°C, was prepared from the above-prepared bis(isooctyloxy)methane using the fluorination technique of Example 1.
• Bis(2-butoxyethoxy)methane was also prepared from methylene chloride and 2-butoxyethanol as follows. A mixture of 590.9 g (5.0 mol) 2-butoxyethanol, 1120 g (20 mol) KOH, 3 g Adogen TM 464 quaternary ammonium salt, and 1 liter tetrahydrofuran was stirred for 30 min. The
• a 600 mL Parr reactor of Monel metal was equipped with a 0.6 cm diameter Monel TM metal gas feed line (for premixed fluorine and nitrogen) with its outlet being about 2.5 cm from the bottom of the reactor, a 0.15 cm diameter nickel organic feed line with its outlet being about 7.5 cm below the top of the reactor, and a condenser cooled by the same bath as the jacket.
• the condenser was a 50 cm long straight double-tube construction, the inner tube having a diameter of about 1.2 cm and the outer tube having a diameter of about 2.5 cm. Gases from the reactor are cooled as they flow through the inner tube by
• This reactor was charged with 450 mL Freon 113 and 105 g (2.5 mol) NaF. The reactor was purged with nitrogen (175 mL/min) for 1 hr while stirring at 3°C. Fluorine was introduced into the nitrogen stream at 35 mL/min. After 15 min, a solution of 15.7 g (0.063 mol) of the above prepared bis(2-butoxyethoxy)methane diluted to 200 mL with Freon 113 was placed in a syringe pump and addition of the resulting solution was started at 9.2 mL/hr. The
• This perfluoroacetal product had a boiling range of 100-110°C/40 Torr, boiling point of 183°C, pour point of -95°C, and viscosities of 147 cs, 504 cs, and 858 cs at -70°C, -80°C, and -85°C, respectively. (In another run, the product had viscosities of 117 cs and 690 cs at -70°C and -85°C, respectively). Traces of acid fluoride and hydrides (0.02 mg/g) were present ( as found by infra-red and proton nuclear magnetic resonance
• the perfluoroacetal product was purified by stirring it with hot, aqueous KOH (25%) for 18 hrs, then washing the separated product with water and drying the washed product over silica gel.
• the distilled residue was purified by bubbling into it for 5 hrs at 175°C a mixture of fluorine diluted with nitrogen. Both purification procedures gave colorless, odorless, thermally stable perfluoro-bis(2-butoxyethoxy)methane.
• the thermal stability was determined by heating the purified product with aqueous sodium acetate for 22 hrs. at 180°C in a closed, stainless steel tube and
• the precursor was fed (diluted in Freon 113) to a mixture of Freon 113 and NaF at 18°C with the condenser set at -25°C (resulting in 50% yield compared to a yield of 77% from a run where no NaF was used). Another run without NaF at 0°C gave a 65% yield.
• the precursor was fed undiluted into Fluorinert FC-72 at 18°C (58% yield), and in another, fed diluted in Freon 113 into a slurry of NaF and
• the condenser was set at -25°C.
• the precursor was fed undiluted into Fluorinert FC-75 at 70°C (55% yield) and in another run, fed undiluted into Fluorinert FC-87 at 20°C (42% yield).
• the condenser was set at about -25°C.
• H-nmr indicated it contained 0.3 mg H/g liquid.
• the tetraoxaheptadecane prepared as described above, was fluorinated by the liquids fluorination technique of Example 7 at about -5°C in the presence of NaF to produce C 6 F 13 OCF 2 O(C 2 F 4 O) 2 C 2 F 5 , which had a boiling range of
• perfluoroacetal compositions each containing a single perfluoroacetal compound listed below (except as
• diphenoxymethane 11. (cyclo-C 6 F 11 CF 2 O) 2 CF 2 , boiling range of 95-115° C/10 Torr, pour point of -60°C, and viscosity at -70°C of >2000 cs, made from dibenzyloxymethane.
• the hydrocarbon product was fluorinated in a 22-liter stirred tank reactor which contained 6 liters of 1,1,2- trichlorotrifluoroethane and 1300 g sodium fluoride powder.
• a gas dispersion tube in the bottom of the reactor provided an inlet for the fluorine and nitrogen gases.
• the hydrocarbon reactant (275 g) was diluted with 1,1,2-trichlorotrifluoroethane, in a separate vessel, to give a total volume of 700 ml. This solution was metered into the fluorination reactor over a 20-hour period.
• the reactor temperature was maintained at 0°C with external cooling throughout the reaction while the fluorine flow was set at a leval 10% higher than that required to theoretically replace all of the hydrogens on the material entering the reactor.
• the fluorine was turned off and the reactor was removed from the low temperature bath and purged for 30 min with nitrogen (2 liters/min) to remove the unreacted fluorine.
• 1,1,2-trichlorotrifluoroethane and 1055 g sodium fluoride gave 401 g fluid in an 18 hr reaction at 0°C.
• the product (259 g) was diluted with 400 ml 1,1,2-trichlorotrifluoroethane and was slowly metered into a 10°C reactor containing 5.7 liters of 1,1,2-trichlorotrifluoroethane and 1200 g sodium fluoride powder.
• a fluorocarbon fluid (660 g, 88.7% yield) was obtained following filtration and removal of the 1,1,2-trichlorotrifluoroethane. Fluorination of the fluid at 220°C with 30% fluorine for 12 hr followed by distillation gave a 60% yield of a fluid, bp 262°C, whose F-nmr spectra was consistent with the following structure:
• a 306 g sample of the fluid was diluted with 450 ml of 1,1,2-trichlorotrifluoroethane and slowly pumped into a -6°C reactor over a 23 hr period.
• the reactor contained 1450 g of sodium fluoride powder (to react with the hydrogen fluoride formed during the reaction) and 6 liters of 1,1,2-trichlorotrifluoroethane. Filtration of the product followed by distillation gave 736 g of fluid.
• the perfluorinated fluid had a bp of 260.0°C and its F-nmr spectra was consistent with the foregoing structure.
• a 1 liter flask cooled to -10°C was charged with 250 g triethylene glycol ethyl ether and a catalytic amount of methanesulfonic acid. To this solution was added slowly 100 g diethylene divinyl ether. Following the addition, the flask was slowly warmed to room temperature over a 3 hr period. The product was distilled to 150°C at 0.05 mm Hg to remove any unreacted starting materials.
• Example 28 to give a perfluorinated fluid of the following structure:
• the product was fluorinated in a 22 liter stirred tank which contained 5.7 liters of
• 1,1,2-trichlorotrifluoroethane and 1100 g sodium fluoride powder were diluted to a volume of 700 ml with 1,1,2-trichlorotrifluoroethane.
• the solution was slowly pumped into the fluorination reactor, which was held at -5°C, over a period of 28 hr.
• the fluorine flow was set at a level approximately 10% higher than that required to react with all of the organic entering the reactor.
• 1,1,2-trichlorotrifluoroethane via a distillation gave a fluorocarbon product which was further purified by a 12 hr fluorination at 200°C with 40% fluorine. Approximately 520 g of fluid was recovered with approximately 50% being a material with a bp of 245.5°C and a F-nmr spectra consistent with the following structure:
• Butoxyethoxyethanol 400 g, 2.47 mol was reacted with 130 g polymeric chloroacetaldehyde in 150 ml benzene to give a fluid which distilled at 190°C at approximately 1 torr.
• the product (266 g) was mixed with 500 ml 1,1,2- trichlorotrifluoroethane and pumped into a 15 liter fluorination reactor containing 5.7 liters 1,1,2-trichlorotrifluoroethane and 1150 g sodium fluoride powder.
• Fluorine diluted with approximately four volumes of nitrogen, was metered into the 0°C reactor at a rate approximately 10% greater than that required to react stoichiometrically with the polyether.
• the organic feed rate was set to allow complete addition in approximately 23 hours. Filtration of the product and removal of the 1,1,2-trichlorotrifluoroethane via a distillation gave a fluorocarbon product which was further purified by a 12 hour fluorination at 200°C with 40% fluorine.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• General Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Applications Claiming Priority (4)

Publications (1)

Family

ID=26940842

Family Applications (1)

Country Status (6)

Families Citing this family (23)

Family Cites Families (7)

• 1989
  • 1989-09-28 EP EP89912727A patent/EP0436669A1/de not_active Withdrawn
  • 1989-09-28 WO PCT/US1989/004264 patent/WO1990003357A1/en not_active Application Discontinuation
  • 1989-09-28 JP JP1511744A patent/JPH04503946A/ja active Pending
  • 1989-09-28 AU AU45243/89A patent/AU4524389A/en not_active Abandoned
  • 1989-09-28 CA CA000613893A patent/CA1340294C/en not_active Expired - Lifetime
• 1990
  • 1990-05-30 KR KR1019900701150A patent/KR900701711A/ko not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events