JPH0547530B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD This invention is in the field of chemistry, polymer and fluorine chemistry. Background Art Generally, esters and ethers have the following structural forms:

[Formula] R ³ -O-R ⁴ An etheric organic molecule containing oxygen, R ¹ , R ² , R ³
and R ⁴ represents an organic group. Esters and ethers can be present in polymeric form, for example as shown in the following illustrative formula:

[Formula] R ¹ (-R ² -O-R ³ -O) - _o R ⁴ polyether n indicates a large integer, and the substance in parentheses indicates a "repeat unit", which is one or more May contain an ester bond. It is possible to fluorinate ester and ether compounds. In such a reaction,
As shown in the following reaction equation, Fluorine atoms replace hydrogen atoms. If the fluorination reaction proceeds to completion, i.e., all hydrogen atoms are replaced by fluorine atoms, the resulting compound is termed "perfluorinated" and is e.g. As it is: Perfluorinated organic groups are referred to herein by the symbol Rf, while partially fluorinated organic groups are referred to by the symbol "Rh/f." The concept of perfluorination can also be applied to polymers. For example, "perfluorinated polyethers" contain all hydrogen atoms (or, as stated below,
shows a polymeric ether molecule in which substantially all of the atoms (substantially all) have been replaced by fluorine atoms. Organic materials are fluorinated by any of several methods known to those skilled in the art. Such methods are broadly divided into two categories, commonly referred to as "direct fluorination" and "indirect fluorination." Direct fluorination means contacting the material with fluorine in elemental form, such as fluorine gas (F ₂ ). This type of reaction is highly exothermic and can lead to adverse effects such as breaking of carbon-carbon bonds.
Direct fluorination is therefore often carried out at low temperatures using fluorine gas diluted with an inert gas such as helium or nitrogen during the initial contact [1]. The concentration of fluorine may be increased gradually or stepwise until pure fluorine gas surrounds the material.
Gas pressure and temperature may also be increased during the fluorination step. Indirect fluorination refers to contacting the material to be fluorinated with a fluorine-containing compound such as sulfur tetrafluoride ( _SF4 ), sulfur hexafluoride ( _SF6 ), or molybdenum hexafluoride ( _MoF6 ). . Upon heating or other manipulations, such compounds are induced to release fluorine atoms. The released fluorine atoms react with the contact material to form the desired fluorinated or perfluorinated material. Several monomeric perfluorinated ether compounds and methods for producing such compounds are known [2]. Such compounds have the following drawbacks. 1 Perfluorinated polyethers with more than two or three carbon atoms between adjacent oxygen atoms are not normally available. i.e.

[Formula] exists, but

[Formula] is not normally available. 2 Perfluorinated polyether compounds with alternating units such as (-R ¹ _f -O-R ² _f -O)- are not commonly available. 3 Most perfluorinated polyethers are perfluorinated vinyl or perfluorinated epoxide monomers. It is produced by fluorinating. However, the precursor perfluoroepoxide,
It is particularly difficult to synthesize epoxides containing bulky fluorocarbon groups. Also, it is difficult or impossible to polymerize perfluoroepoxides containing bulky perfluoro groups (R ¹ _f →R ⁴ _f ). No polymerization occurs or very low molecular weight products are obtained. Some polymerized perfluoroethers are also known. Such compounds are believed to be extremely stable; for example, the only reported reaction of a saturated perfluoroether known to Applicants was to react the chain in the ether bond with aluminum chloride at elevated temperature and pressure. This is the division of [3]. Saturated perfluoropolyethers also tend to have a relatively wide liquid range and can be used in solvents, hydraulic fluids, heat transfer fluids, lubricants, greases, sealants,
It has viscosity and surface properties that make it attractive for many applications such as elastomers and plastics. It is known that various types of polymeric perfluoroethers can be produced by direct fluorination of hydrocarbon polyethers [4]. However, the generality of this method is limited by the fact that only relatively few hydrocarbon polyether compounds are commercially available. In order to make a wide variety of perfluoropolyether compounds, a large number of polymeric precursors with a variety of repeating units must be available. Fluoroethers can be made by fluorination of ester compounds. A known reaction to achieve this result utilizes SF ₄ as the fluorinating agent according to the following equation [5]. This reaction has been used to convert various highly fluorinated monoesters to highly fluorinated monoethers [6]. The SF ₄ reaction has also been used to make certain forms of polyethers [7]. but,
Polyether compounds made with SF ₄ have several limitations. 1 The polyether was not perfluorinated and could not be perfluorinated by known techniques without substantial amounts of undesirable by-products. 2 In the SF ₄ reaction, the product had a certain amount of reactive acid end groups. The only uses cited for this compound require crosslinking and curing steps to convert the compound to an elastomer. This background art did not provide a general method for making stable perfluorinated polyethers with a sufficient variety of repeating units. DISCLOSURE OF THE INVENTION This invention relates to polymerized perfluoroether compounds and to a general method for making such compounds. Compounds of this type can be made by a three-step process that can be carried out using a wide variety of polyester starting materials. Generally, the first step of this three-step process consists of partial fluorination of the selected polyester compound. This may be accomplished by known techniques, including direct fluorination, which involves contacting the selected polyester with fluorine gas under predetermined conditions until the desired level of partial fluorination is achieved. include. The second step of this three-step process involves indirect fluorination to convert the partially fluorinated polyester to a partially fluorinated polyether. This step may be carried out by contacting the partially fluorinated polyester with _SF4 . Such contacting may be carried out at elevated temperatures or in the presence of other compounds that promote the desired reaction, such as HF gas. The third step of this three-step synthesis method consists of directly fluorinating the partially fluorinated polyether compound under conditions that substantially complete the perfluorination reaction, thereby creating a perfluorinated polyether compound. ing. The present invention consists of a general process for converting hydrogen-containing polyester compounds to perfluoropolyether compounds. By carefully selecting the polyester starting materials, the present invention provides a general and widely applicable method of making perfluoropolyether compounds with selected repeat units and components. Such compounds have a variety of properties that make them useful for one or more specific applications. To the best of Applicants' knowledge, this method provides the only practical way to make perfluoroether compounds with one or more of the following properties; namely: 1 desired sequence, e.g. R _A −O−R _B −O)—,
(in the formula, R _A is different from R _B ), an organic group between repeated ether bonds. Such compounds may be made by using copolyester compounds (ie, polyesters formed by polymerizing two or more monomeric compounds) as starting materials. 2 Long, complex, or bulky components. At least one supplier uses propyl monomers to make polyether compounds;
Contains only CH ₃ ) components. In contrast, alkyl,
A wide variety of polyester compounds containing aryl and branched components are not available. Such compounds are good candidates for conversion to perfluoropolyethers by the method of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a simplified representation of the direct fluorination mechanism. BEST MODE FOR CARRYING OUT THE INVENTION One preferred embodiment of the invention utilizes the system depicted in FIG. Hydrogen-containing polyester compounds such as polybutylene adipate are utilized as starting materials. If the starting material is in solid state, it may be ground and sieved to a powder if desired. Place it in a shallow dish 1, often called a "boat". Like all components of this system, the boat should be made of or coated with a fluorine resistant material such as nickel or monel alloy. The loaded boat is placed into the reaction chamber by removing the end plate from the reaction chamber. The reactor chamber 2 is completely flushed with helium gas entering the system through the flow meter 3 and metering valve 4. If desired, the temperature within chamber 2 may be lowered or raised by various means, such as contacting the outside of the chamber with cold or hot liquid. When all oxygen, water, and other undesirable molecules have been removed from the chamber, fluorine gas enters the system through flow meter 5 and metering valve 6. Fluorine and helium are mixed together in mixing chamber 7 and introduced into reaction chamber 2. If desired, the system may be equipped with one or more valves, traps, or other devices downstream of the reaction chamber. For example, suction trap 8
(as well as the reaction chamber itself) with granular sodium fluoride (NaF) and hydrogen fluoride (HF) from the gas stream.
may be removed. Condensation trap 9 may be immersed in cold material to condense volatile materials in the exit gas stream for analysis, recovery or other purposes. The system may be protected from oxygen diffusion by addition of an inert gas (eg nitrogen) under low pressure through valve 10. The exiting gas passes through an adsorption trap 11 to remove unreacted fluorine and through mineral oil which turns black on contact with fluorine, thereby indicating when the adsorbent in trap 11 should be replaced. During initial contact, the fluorine gas is diluted with helium. This allows the fluorination reaction to start slowly and reduces the degree of cleavage of the polyester that creates undesirable by-products. The concentration of fluorine gas is increased gradually or stepwise until the desired level of fluorination is achieved. The fluorine flow is continued until the desired degree of fluorination is achieved. If desired, valve 12 may be closed to increase the chamber pressure. After stopping the fluorine flow, flush the system with helium. If desired, the resulting product may be cured at elevated temperatures in an inert gas. Using this method poly(2,2-dimethyl-
The partial fluorination of 1,3-propylene succinate) may be expressed by the following non-stoichiometric equation. In the formula, a+b+c+d=14. Poly(2,2-dimethyl-1,3-propylene succinate) was extensively contacted with pure fluorine gas during experiments by applicants, and the degree of fluorination (sum of b + d) was 14 per repeating unit. Usually limited to about 12-13 of the hydrogens. Even if attempts are made to increase the degree of fluorination by increasing the reaction temperature or pressure, poly(2,2-dimethyl-1,3-propylene succinate) tends to be converted to undesirable by-products. It was hot. The resulting material, called hydrofluoropolyester, was cooled and placed in a cryoreactor and contacted with anhydrous HF gas. SF ₄ gas was then transferred to the reaction chamber by vacuum distillation, and the reaction chamber was cooled to −196° C. during the process. The container is then heated from about 180℃
It was heated to a reaction temperature of 190°C and shaken for a reaction time of about 20 to 24 hours. SF ₄ reacted with the ester group by replacing the carbonyl oxygen with two fluorine atoms, thereby converting the ester bond into an ether bond. Volatile products were removed by vacuum fractionation.
The non-volatile oil product was removed from the vessel by adding Freon-113 solvent, heating and shaking. The solution thus obtained was filtered and concentrated by distillation to approximately a quarter of its volume. Yellow crystals passed and were subsequently determined to contain elemental sulfur. The residual solution was further concentrated by distillation. The resulting material, termed hydrofluoropolyether, is then perfluorinated by direct fluorination using the systems and methods described above, utilizing factors that can be optimized for any particular compound. do. Perfluorination ideally indicates that each hydrogen or other replaceable atom has been replaced by a fluorine atom. However, under actual conditions,
It may be difficult or impossible to replace all substitutable atoms, or it may be difficult or impossible to verify whether all substitutable atoms have actually been substituted. Therefore, perfluorination refers to non-extensive fluorination that has been accomplished with the purpose and practical effect of substituting most or substantially all of the hydrogen or other substitutable atoms in a compound. It is used here in the ideal and functional sense. For example, analysis shows that the economically optimal material for a given application, at a given level of fluorination, even if a small percentage of residual hydrogen atoms are known to remain in the compound. It may be shown that gains can be made by shortening the fluorination reaction and thereby reducing costs. Despite the presence of such residual hydrogen atoms, highly fluorinated compounds of this nature should be considered "perfluorinated" and, if made by the process of the invention, is within the area of As used herein, the terms "ether" and "ester" refer to the ether linkage (-C-O-
C) or ester bond (

[Formula]), regardless of whether such molecules also contain other organic or inorganic groups or moieties, such as sulfur bonds or mercaptan groups. As used herein, the terms "diol" and "diacid" refer to two or more alcohol groups (R-O-H) or carboxylic acid groups (R-O-H) per molecule.

[Formula]), regardless of whether such molecules contain sulfur bonds or other organic or inorganic groups or moieties, such as mercaptan groups. Example 1 Partial fluorination of poly(2,2-dimethyl-1,3-propylene succinate) Fluorine-free poly(2,2-dimethyl-1,
3-propylene succinate) PDPS (Aldrich)
(molecular weight is about 1600) was sieved into a fine powder and 150 mesh. 2520 g of powder was placed in a shallow Nickel dish. The loaded dish was placed in a reactor having a volume of approximately 80 ml. The chamber was flushed with helium and contacted with fluorine under ambient conditions (approximately 23°C) as shown in Table 1.

[Table] The weight of the powder increased from 2520g to 5621g. Elemental analysis after slight hydrolysis of the product
It showed a carbon content of 25.92% (by weight) and a fluorine content of 58.60% (by weight). These show that 12.5 to 13 of the 14 hydrogens per repeating unit were replaced by fluorine. Additional ambient temperature experiments were performed using pure fluorine with longer contact and pressure times. However, the degree of fluorination was not substantially increased by this method beyond about 13 out of 14. Elevated temperatures resulted in the formation of substantial amounts of undesirable by-products. Example 2 SF ₄ Reaction of Hydrofluoropolyester Hydrofluoro-PDPS prepared as in Example 1 was placed into a 75 c.c. stainless steel sampling cylinder. To avoid hydrolysis, the material was handled in a glovebox flushed with inert gas, and a sodium-potassium alloy container was placed in the glovebox to serve as a desiccant. Anhydrous HF and SF ₄ were vacuum distilled into the cylinder using a metal Kel-F vacuum tubing extension and cooled to -196°C with liquid nitrogen. In a typical reaction, 2.0 g of hydrofluoro-PDPS (average molecular weight per repeat unit is about 417, which corresponds to about 4.8 mmol of repeat units) is combined with about 20 ml of anhydrous HF and 4.1 g (38 mmol) of hydrofluoro-PDPS. ) used with SF ₄ . The loaded cylinder was heated and shaken. The preferred reaction time was about 20 to 24 hours. If the volatile products of the reaction are to be analyzed, they are first transferred by vacuum distillation (all metallic) into a cooled (-196 DEG C.) stainless steel cylinder filled with dry NaF pellets. Warm the cylinder and shake for several hours to remove all the hydrofluoric anhydride.
Allow to be consumed by NaHF ₂ formation. The remaining volatile species are pumped from the NaF cylinder into vacuum piping and combined with the low volatile high molecular weight product from the _SF4 reaction cylinder, rather than being distilled into the NaF cylinder.
It is transferred from the reaction cylinder upon exposure to a dynamic vacuum for several hours. The combined volatile products were fractionated in a vacuum system into -78°, -131° and -196° fractions. The -196° and -131° fractions were shown by infrared analysis to contain primarily unreacted SF ₄ , SOF ₂ and SiF ₄ . SO ₂ F is carbonyl by SF ₄
A sulfur-containing byproduct of CF ₂ conversion, SiF ₄ is based on glass erosion due to insufficient HF removal or HF production decomposition of metastable hydrofluoro products. Infrared analysis also shows the presence of small amounts of fluoroacyl fluoride in the −131° cut, but it is difficult to separate these low-yield products from the large amount of toxic sulfur-containing species in this cut. Difficult, dangerous and of little importance. −
The 78° cut contains hydrofluoroacyl fluoride (by IR), but gas chromatographic analysis showed it to be a multicomponent mixture.
From 2 g of starting hydrofluoropolyester,
350 mg (average of two reactions) of a −78° fraction of non-separable hydrofluoroacyl fluoride was produced. The volatile products of the SF ₄ reaction were analyzed for only two reactions. This is because the separation and analysis of fluoro-organic species is difficult and the non-volatile oily residue is of great interest. The non-volatile oily product of the SF ₄ reaction was removed from the reaction cylinder by heating and shaking with several 20 ml aliquots of Freon-113 (CFCl ₂ CF ₂ Cl). The resulting solution was filtered to remove debris from the tube-sealing Teflon tape and some yellow globules. The supersolution was concentrated to approximately 1/4 of its volume by distillation and a small amount of yellow needles were separated. The remaining solution was further concentrated by distillation and the remaining CFCl ₂ CF ₂ Cl solvent was removed by evaporation. A viscous golden oil was obtained. 2.0g
For the starting fluoropolyester, an average of 1.30
g of this oil was obtained. The yellow spheres and crystals were determined to be elemental sulfur by a melting point of 117-119°C and solubility in benzene and carbon disulfide. Sulfur is 50~ from the reaction
Obtained in an amount of 100 mg. Viscous fixed oil from CFCl ₂ CF ₂ Cl solution
A thin oily film cast onto a KBr window was analyzed by infrared spectroscopy. During the run, no provision was made for atmospheric moisture exclusion, so any acyl fluoride end groups or residual fluoroester linkages formed were likely hydrolyzed to acid end groups. The infrared spectra of SF ₄ produced oil were compared with those of hydrofluoropolyester. The hydrofluoropolyester was hydrolyzed by dissolving it in tetrahydrofuran and exposing it to ambient moisture overnight.
Infrared samples were taken from an oily film cast from the resulting solution. Based on a comparison of the relative intensities of carbon-fluorine absorption (1200 cm ^-1 ) and fluorocarbon acid absorption (1780 cm ^-1 ), the _SF4- treated material appeared to have a lower functional group content than the hydrofluoropolyester. . It is believed that the SF ₄ reaction was therefore successful in converting a significant number of ester bonds to ether bonds, ie, carbonyls to CF ₂ , as expected. 3000cm
^-1 region, a wide range of unassociated acids
acid) OH absorption, and a sharper carbon-hydrogen stretching absorption based on residual hydrogen was observed. A weak carbonyl absorption is observed between 1600 and 1650 cm ^-1 ,
This is probably due to the anionic end group of the carboxylate. It was therefore concluded that the fixed oil produced by the SF ₄ reaction is a mixture of functional hydrofluoropolyethers. The lack of volatility and viscous oily nature indicated a relatively high molecular weight. Example 3 Perfluorination of Hydrofluoropolyethers To obtain the desired perfluoroethers, the material obtained by the method of Example 2 is subjected to additional direct treatment using the system and method described herein. Fluoridation was performed. Non-volatile high molecular weight non-functional (acyl fluoride) perfluoroethers should be obtained from ambient temperature fluorination. However, conclusive evidence of ether formation was desired. Since volatile compounds are more easily separated and identified than non-volatile compounds, fragmentation fluorination was performed using elevated temperatures as shown in Table 2.

[Table] The volatile products obtained were first subjected to trap-to-trap fractional distillation in a vacuum system at −196°, −131°,
and -78° fractions. Infrared analysis shows that the larger −196° fraction contains primarily COF ₂ and CF ₄ , likely the result of decarboxylation and chain end degradation, respectively. The very small −131° fraction contained fluoroacyl fluoride (by IR). The higher molecular weight non-volatile compounds in the -78° cut were separated by gas/liquid chromatography.
The isolated compound was determined by GLC retention time to
Their yields and maximum m/e in mass spectrometry are listed in the table. The isolated compounds were characterized and identified by infrared spectroscopy, ¹⁹ N NMR, and mass spectrometry analysis. The infrared spectra are all very similar to each other and to the infrared spectra of other perfluoroethers. They are 1350
It exhibits broad carbon-fluorine and ether carbon-oxygen absorptions of normal strength at ~1100 cm ^-1 and also all at 1000 cm ^-1 (m), 900 cm ^-1 (m), and 750-700 cm ^-1 ( m, wide) with the same "fingerprint"
It showed regional absorption. The 750-700 cm ^-1 band is similar to the broad band observed at 740-700 cm ^-1 for hydrocarbon alkanes with four ordinal methylene (-CH ₂ -) units. Mass spectra were useful in determining the molecular weight and formula. The highest mass peak in each spectrum is the parent minus the fluorine fragments.
fluorine fragment). The mass spectra are similar to other perfluoroethers in that they exhibit extensive fragmentation and rearrangement, and that they exhibit informative high mass peaks only when spectra are taken with a spectrometer ion source cooled to ambient temperature. It was hot. The mass spectra also showed a normal decrease in peak intensity with increasing mass. The common fragment peaks observed were at m/e values corresponding to the following empirical formula: CnF ₂ n+1, C _o F _2o −1 for all compounds (n equals from 1 to the number of carbon atoms in the compound). ,
Cn _F2 n+1 and C _o F _2o +1O; for di and triether, C _o F _2o +1O ₂ , C _o F _2o −1O ₂ ; and for triether, C _o F _2o +1O ₃ , and C _o F _2o − _1O3 . The ¹⁹ F NMR signal for isolated compounds is mostly a broad unresolved multiplet, but with chemical shifts and normalized
Integrated intensity is useful for structural elucidation.

[Table] ¹⁹ F NMR data are listed in Table 4 along with putative structures and signal assignments. The key to structure determination was to conclusively establish the identity of one end group by a characteristic ¹⁹ F NMR signal. The CF ₃ CF ₂ CF ₂ O end group is indicated by a relatively sharp signal ₍ based on internal CF ₂ ) at −133 _{ppm .}
Illustrated by the signal at −90 ppm and −91 ppm (relative intensity 3:2) for CF ₂ nuclei. The CF ₃ O end group has a characteristic signal at about -58 ppm.
The most common branched end group is the (CF ₃ ) ₃ CCF ₂ O (neopentyl) group. The _CF3 nucleus in this group is −
It has a chemical shift of 65 ppm, while CF ₂ O is −
with a shift of 68 ppm, giving a relative ratio of 9:2, respectively. The other branched terminal group _{( CF3} ) _2CFCF2O has a _CF3 chemical shift of −75 ppm, while the corresponding _CF2O in this group has a −77 ppm
The chemical shifts of 9 and relative intensities are 6:2, respectively.
It is. Once a terminal group has been established using mass spectral data and the symmetry of the molecule with respect to the repeat units in high molecular weight polymers, structure elucidation becomes a routine task. The cleavage fluorination of the SF ₄ reaction product at this point was brief and as mild as possible. This was done to leave a non-volatile, non-functional, viscous perfluoro oil in the reactor without cutting off all of the oil. The infrared spectrum taken for this oil was the same as expected for the volatile product. The ¹⁹ F NMR spectrum of this product showed all of the chemical shifts shown in the ¹⁹ F NMR of non-volatile products. A less volatile and relatively viscous mixture means that the compound contained is of higher molecular weight than the isolated volatile perfluoroether. Cutting conditions may be varied to obtain the minimum amount of volatile products and maximize the yield of fixed oil produced by this step. Conditions may also be varied to obtain maximum yields of volatile products and minimum amounts of non-volatile products.

【table】

[Table] Fluorosilicone QF on Cromosorb P-
GC separation on a 3/8 inch x 25 ft (0.95 cm x 7.5 m) column using 1-0065. 20 minutes
Planned at 1°/min to 0° and 100°C. Helium flow 100c.c./
Minutes. Based on the synthetic procedure used and the spectral data obtained for this fixed oil, the main compound of this oil is perfluoropoly(2,2-dimethyl-
1,3-propylene-oxa-tetramethylene-
oxide) and is believed to have the following structural formula: Example 4 Perfluoropoly(2,2-dimethyl-1,3
-propylene oxide) 2,2-dimethyl-1,3-propanediol is reacted with 2,2-dimethylmalonic acid in the following manner. This material was then contacted with fluorine gas using the method of Example 1. Hydrofluoro-poly(2,
2-dimethyl-1,3-propylene-2,2-dimethylmalonate was prepared. This hydrofluoropolyester was reacted with SF ₄ using the method described in Example 2 to produce hydrofluoro-poly(2,2-dimethyl-1,3-propylene oxide), a partially fluorinated ether compound.
This material was perfluorinated using the method of Example 3 to give the following structural formula: Perfluoropoly(2,2-dimethyl-
1,3-propylene oxide). Example 5 Perfluoropoly(1,1-dimethylene oxide) α-hydroxyisobutyric acid was itself used in the following reaction. were reacted in a condensation polymerization to form poly(isobutyrate) according to the following. This material was then contacted with fluorine gas using the method of Example 1 to form hydrofluoro-poly(isobutyrate). This hydrofluoropolyester was converted to SF ₄ using the method described in Example 2.
Hydrofluoro-poly(1,1
-dimethylene oxide), a partially fluorinated ether compound. This material was perfluorinated using the method described in Example 3 and had the following structural formula: We created perfluoropoly(1,1-dimethylene oxide) with Example 6 Perfluoropoly(2,2,4,4-tetramethyl-1,4-butylene oxide) 2,2,4,4-tetramethyl-4-hydroxybutyric acid itself was subjected to the following reaction. According to poly(2,2,4,4-tetramethyl-
It was possible to react in condensation polymerization to produce (butyrate). This material was then contacted with fluorine gas using the method of Example 1 to obtain hydrofluoro-poly(2,
2,4,4-tetramethyl-butyrate). This hydrofluoropolyester was reacted with _SF4 using the method described in Example 2 to obtain hydrofluoropoly(2,2,4,
4-tetramethyl-1,4-butylene oxide), a partially fluorinated ether compound. This material was perfluorinated using the method described in Example 3 to give the following structural formula: Perfluoropoly(2,2,4,4-tetramethyl-1,4-butylene oxide) having the following properties was prepared. Example 7 Perfluoro-poly(2,2-di-tert-butyl-ethylene oxide) 2,2-di-tert-butyl-(α-hydroxy)-acetic acid was itself reacted in a condensation polymerization to form the following reaction Poly(2,2-di-tertiary-butyl acetate) was prepared according to the following procedure. This material was then contacted with fluorine gas using the method of Example 1 to obtain hydrofluoro-poly(2,2
- tertiary butyl acetate). This hydrofluoropolyester was reacted with _SF4 using the method of Example 2 and
Hydrofluoro-poly(2,2-di-tert-butylethylene oxide), a partially fluorinated ether compound, could be produced. This material was then perfluorinated using the method described in Example 3 to give the following structural formula: We were able to produce perfluoropoly(2,2-di-tert-butylethylene oxide) having the following properties. Example 8 Perfluoropoly(1,1-dineopentylethylene oxide) 2,2-dineopentyl-(α-hydroxy)
Poly(2,2-dineopentyl acetate) is reacted with acetic acid itself in a condensation polymerization following the reaction This material was then contacted with fluorine gas using the method of Example 1 to obtain hydrofluoro-poly(2,2
-dineopentyl acetate). This hydrofluoropolyester could be reacted with SF ₄ using the method of Example 2 to produce hydrofluoro-poly(1,1-dineopentylethylene oxide), a partially fluorinated ether compound. This material was then perfluorinated using the method described in Example 3 to form the following structural formula: We were able to create perfluoropoly(1,1-dineopentylethylene oxide) with the following properties. Example 9 Perfluoropoly(tetramethylethylene-oxa-2,2-dimethyl-1,3-propylene oxide) 2,2-dimethylmalonic acid is reacted with 1,1,2,2-tetramethylethylene glycol in condensation polymerization. React, then next reaction According to poly(1,1,2,2-tetramethyl-
1,2-ethylene-2,2-dimethylmalonate). This material was contacted with fluorine gas using the method of Example 1 to obtain hydrofluoro-poly(1,1,
2,2-tetramethyl-1,2-ethylene-2,
2-dimethylmalonate). This hydrofluoropolyester was then reacted with _SF4 using the method described in Example 2,
Hydrofluoropoly(tetramethylethylene-
Oxa-2,2-dimethyl-1,3-propylene oxide), a partially fluorinated ether compound, could be produced. This material was then perfluorinated using the method of Example 3 to give the following structural formula: We were able to produce perfluoropoly(tetramethylethylene-oxa-2,2-dimethyl-1,3-propylene oxide) having the following properties. Example 10 Perfluoropoly(2,2-propylene-oxa-ethylene oxide) Acetone is reacted with oxalic acid in condensation polymerization to produce the following reaction. Poly(2,2-propylene oxalate) could be prepared according to the following. This material was then contacted with fluorine gas using the method of Example 2 to obtain hydrofluoro-poly(2,2
-propylene oxalate). This hydrofluoropolyester can then be reacted with _SF4 using the method described in Example 2 to form hydrofluoro-poly(2,2-propylene-oxa-ethylene oxide), a partially fluorinated ether compound. did it. This material was perfluorinated using the method in Example 3 to give the following structural formula: Perfluoropoly(2,2-propylene-
Oxa-ethylene oxide) could be produced. Equivalents Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific devices and methods described herein. Such equivalent schemes are considered to be within the scope of this invention and are covered by the claims. It may be possible to give more than one chemical name to one or more substances given a structural formula. The claims are intended to cover the ether compounds disclosed by this invention, regardless of the name given to them. Literature 1 For example, US Pat. No. 4,281,119 (Lagow et al.
(1981). 2 For example, J. Polymer by GEGerhardt et al.
Science: Polymer Chemistry Ed.18:157−
168 (1979); U.S. Patent No. 3,985,810 (von
Halasz et al., 1976). 3 GVDTiers, J.Amer.Chem.Soc.77:4837
(1955). 4 For example, GEGerhardt et al., J.Org.Chem.43:
4505 (1978); GEGerhadt et al., JCSPerkin
1321 (1981). 5 WRHasek et al., J.Amer.Chem.Soc.82:543
(1960); WC Smith, Angew.Chem.Inst.Ed.
1:467 (1962); WA Sheppard, J.Org.
Chem.29:1, 11 (1964). 6 RJDe Pasquale, J.Org.Chem.38:3025
(1973) 7 U.S. Pat. No. 4,201,876 (Griffin, 1980); U.S. Pat. No. 4,238,602 (Griffin, 1980).

[Brief explanation of the drawing]

Figure 1 is a simplified representation of the direct fluorination mechanism. 1: Dish, 2: Reaction chamber, 3, 5: Flow meter, 7: Mixing chamber, 8, 9, 11: Trap.

Claims (1)

[Claims] 1 (a) Formula, R ¹ -C(O)-O-R ² , where R ¹ and R ² are independently an alkyl group or an aryl group having a straight or branched chain; , the ester, which may contain sulfur or mercaptan groups, is reacted with fluorine gas under an inert gas atmosphere to partially fluorinate the ester; (b) the partially fluorinated ester; The carbonyl group on the partially fluorinated ester is reacted with a stoichiometric excess of sulfur tetrafluoride at temperatures above ambient temperature.
( _c ) reacting the partially fluorinated ether compound in an atmosphere of fluorine gas and an inert gas at an elevated temperature above ambient temperature; Perfluorinating this partially fluorinated ether compound; A method for producing a perfluorinated ether compound, which comprises various steps. 2. Steps (a) and (b) are carried out independently using a mixture of fluorine gas and an inert gas, and the concentration of fluorine gas therein is gradually or stepwise increased while the reaction proceeds. A method according to claim 1. 3. The method of claim 1, wherein the ester and the fluorine gas are reacted at ambient temperature. 4. The method of claim 1, wherein step (b) reacts the partially fluorinated ester with hydrogen fluoride and sulfur tetrafluoride. 5 (a) polymerizing at least one diol compound and at least one diacid compound to form a polyester, the polyester having the formula R ¹ −(R ² −
C(O)-O- ^R3 )n- ^R4 , where ^R1 and ^R4 are independently an alkyl group or an aryl group having a straight or branched chain, and this group contains a sulfur or mercaptan group. R ² and R ³ may independently be straight or branched alkylene or aryl groups, which may contain sulfur or mercaptan groups, and n is an integer. (b) partially fluorinating the polyester by reacting the polyester in an atmosphere of fluorine gas and an inert gas; (c) partially fluorinating the partially fluorinated polyester with a stoichiometric excess of sulfur tetrafluoride; reacting at a temperature above ambient temperature to convert the carbonyl groups on the partially fluorinated polyester to CF ₂ to prepare a partially fluorinated polyether compound; (d) reacting the partially fluorinated polyether compound with fluorine gas; A method for producing a perfluorinated polyether compound, which comprises several steps: perfluorinating the partially fluorinated polyether compound by reacting in an inert gas atmosphere at a high temperature equal to or higher than ambient temperature. 6. A patent in which steps (b) and (c) are carried out independently using a mixture of fluorine gas and an inert gas, and the concentration of fluorine gas therein is gradually or stepwise increased while the reaction proceeds. The method according to claim 5. 7. The method of claim 5, wherein the polyester of step (b) is reacted with fluorine gas at ambient temperature. 8. The method according to claim 5, wherein step (c) is carried out by reacting the partially fluorinated polyester with hydrogen fluoride and sulfur tetrafluoride.