JPH0451559B2 - - Google Patents

Description

[Detailed description of the invention]

"Industrial Application Field" The present invention relates to a novel fluoroalkoxy cyclic phosphonitrile ester, and more specifically, to a fluoroalkoxy cyclic phosphonitrile ester having a 1,1,1,3,3,3-hexafluoro-2-propoxy group. This article relates to alkoxy cyclic phosphonitrile esters and their uses. The substance according to the present invention (hereinafter referred to as "the substance") is a cyclic oligomer (trimer or tetramer, or
and a mixture of pentamer or more) and 1,1,1,
3,3,3-hexafluoro-2-propanol and one or more 1,1,w-trihydro perfluoroalcohols (C=3,5,
7,9), and is a mixed fluoroalkoxy cyclic phosphonitrile ester represented by the following formula (). [{CF ₃ ) ₂ CHO}l {H(CF ₂ CF ₂ ) _n CH ₂ O} _2o-l
(PN) _o ] ...() (In the formula, (PN) _o means a phosphonitrile ring,
m means a real number within the range of 1.3≦m≦2.8, n means a real number within the range of 3≦n≦4.3, and l means a real number within the range of 1≦l≦2n-1. ) Considering the basic structure, constituent elements, and physical properties, the substance may be used in nonflammable lubricating oils and hydraulic oils, and rotary pump oil is a particularly applicable application. ``Prior art'' and ``Problems to be solved by the invention'' Rotary pump oil has particularly stringent quality requirements among various lubricating oils, and has low vapor pressure, low viscosity, and appropriate viscosity index, and has a temperature below freezing. It is required to maintain fluidity even at temperatures of several tens of degrees, have excellent oxidation stability and heat resistance, and have good lubrication properties. General rotary pump oil is a petroleum-based lubricating oil with extremely low vapor pressure and excellent heat resistance, which is obtained by fractionating and refining a petroleum lubricating oil fraction with a kinematic viscosity of 30 to 150 centistokes at 40°C using molecular distillation, etc. It is widely used as it satisfies the required performance. However, in recent years, as the field of vacuum applications has expanded, the performance required of rotary pump oil has also become more advanced, and there are many cases where petroleum-based rotary pump oil is unable to meet these demands. . In particular, with the expansion of the use of vacuum in thin film manufacturing technology, there is a strong desire for a rotary pump oil that has excellent resistance to active gases such as halogen compounds. For example, rotary pump oil for dry etching equipment used in the semiconductor manufacturing process uses a mixed gas of Freon-14 and oxygen as the active gas, so conventional petroleum-based rotary pump oil can quickly increase the viscosity of the oil. Sludge deposition occurs, requiring frequent oil changes and requiring a great deal of time and effort to maintain the rotary pump. Therefore, a rotary pump oil that is particularly resistant to these active gases is required. Currently, equipment that requires the use or exhaust of active gas includes semiconductor manufacturing equipment such as various dry etching equipment, ion implantation equipment, and plasma CVD equipment, CVD equipment for cemented carbide cutting tools, and halogen lamps. manufacturing equipment, steel degassing equipment, superconducting material manufacturing equipment, etc. In addition, active gases include phosphine, arsine, diporan, hydrogen selenide, arsenic trichloride, silane, silicon tetrachloride, hydrogen chloride, dichlorosilane,
Freon-14, ammonia, phosphorus pentafluoride, silicon tetrafluoride, carbon tetrachloride, oxygen, etc.
They are used alone or in combination of two or more types. The conventional rotary pump oils used in the above equipment are subject to severe oil deterioration due to reactions with active gases, and for example, in the case of chlorine-based active gases, the viscosity of the pump oil is reduced. However, in the case of fluorine-based products, changes such as an increase in viscosity and precipitation of sludge occur, making it impossible to use them for long periods of time. Development of new pump oil is desired. "Means for Solving the Problems" The present inventors have confirmed that the substance of the present formula () can satisfy the above requirements, and have completed the present invention. Here, in this substance (), if m is smaller than 1.3, the vapor pressure will be high and the specified degree of vacuum cannot be reached, and if it is larger than 2.8, the viscosity at room temperature will be high and the device will not start. Sometimes excessive power is required, which is inconvenient for the purpose. Also, if l is less than 1, the viscosity at room temperature is high and may cause swelling of the fluorine-based elastomer, while if it is greater than 2n-1, it is solid at room temperature, so it is very difficult to use as a rotary pump oil. It is inconvenient for In addition, the phosphonitrile halide, which is the raw material for this substance, is
Those with n of less than 3 are hardly produced, and those with n of more than 5 are only a few percent at most, and since the viscosity is high, the range of n is substantially the above value. The mixed fluoroalkoxy cyclic phosphonitrile ester of the present invention can be synthesized from an appropriately prepared alcoholate of a fluoroalcohol and a phosphonitrile halide as in the Examples below. The substances in question are ketones such as acetone and methyl ethyl ketone, ethers such as ethyl ether, isopropyl ether, and tetrahydrofuran, lower alcohols such as ethanol and isopropyl alcohol, aromatics such as benzene and toluene, and fluorine-based substances such as Freon 113. Soluble in solvents, water, n-
Almost insoluble in hexane. "Example" Example 1 In a four-necked flask equipped with a condenser, a stirrer, and a thermometer, 173 g (1.03 mol) of 1,1,1,3,3,3-hexafluoroisopropanol and 1,1,
5-trihydroperfluoropentanol 240g
(1.03 mol) (m=2) and 1000 ml of toluene were charged, and while cooling, 45.3 g (1.97 mol) of sodium was added little by little, and the reaction was carried out at 40 to 50°C for about 5 hours. A solution of 89 g (0.192 mol) of phosphonitrile chloride tetramer dissolved in 800 ml of toluene was added dropwise to this reaction solution at about 50° C., and the reaction was stirred under reflux for 4 hours. After washing with water to remove the generated sodium chloride, dehydrating, and concentrating, the oily crude product 320
I got g. Distill this under reduced pressure to 160-190℃/0.05
A fraction of 250 g of mmHg was collected. This slightly yellow transparent oil has the following IR spectrum (Figure 1):
Tetrameric phosphonitrile skeleton (n=4) at 1380 cm ^-1
1 H-NMR spectrum (Figure 2)
It was confirmed from the proton integral value that l = 3.4. Furthermore, it was confirmed by GC analysis (Figure 3) that it was a mixture of seven components. The physical properties of this mixture (hereinafter referred to as "fluorophosphonitrilate (A)") are: specific gravity: 1.78 (20°C), viscosity:
250 cps (40°C), vapor pressure: 1 mmHg/185°C, pour point: -35°C, and refractive index: 1.3470 (20°C). Example 2 In the same manner as in Example 1, 173 g of 1,1,1,3,3,3-hexafluoroisopropanol and 1,1,
5-trihydroperfluoropentanol 240g
An alcoholate was prepared using 45.3 g of sodium and a mixture of phosphonitrile chloride (70% trimer, 20% tetramer, 10% pentamer or higher) 89
A toluene solution containing 160 to 200 g of
230 g of a fraction of °C/0.05 mmHg was obtained. This thing is
-20ppm (n=3) of 31P-NMR spectrum,
Intensity ratio of 7.5ppm (n=4) and 17ppm (n=5) 14:
From 5:1, n was 3.35, and from ¹ H-NMR spectrum, l was 1.95. The IR spectrum of this product is shown in Figure 4, ¹ H-
The NMR spectrum is shown in FIG. This mixture has a specific gravity of 1.77 (20℃) and a vapor pressure of 1 mmHg/180.
Viscosity: 240cps (40℃), Pour point: -35℃, Refractive index:
It was 1.3475 (20℃). This substance is called "fluorophosphonitrilate (B)." Example 3 173 g of 1,1,1,3,3,3-hexafluoroisopropanol and 1,1,w,-trihydroperfluorotelomeric alcohol {ratio of m in formula () is m=1:33%, m=2:42%, m=
3:17%, m=4:5%, m=5:3% (G, C
analysis value), and the average value of m calculated from the measured value of hydroxyl value is 2.03} Using 244 g, post-reaction treatment and distillation were performed in the same manner as in Example 1, and 160
220g of fraction at ~200°C/0.05mmHg was obtained. (This substance is called "fluorophosphonitrilate (C).") This mixture has a specific gravity of 1.77 (20℃) and a vapor pressure of:
1mmHg/185℃, pour point: -30℃, refractive index
1.3472 (at 20° C.), and l was found to be 1.8 from the integral ratio of the NMR spectrum shown in FIG. Example 4 Based on Example 1, 1,1,1,3,3,3-
Hexafluoroisopropanol and 1,1,5-
trihydroperfluoropentanol and 1,
The reaction was carried out using an equimolar mixture of 1,7-trihydroperfluoroheptanol (0.69 mol each) and 89 g of phosphonitrile chloride trimer,
After post-treatment and distillation, 160-200℃/0.05mmHg fraction
Obtained 277g. This oil has a specific gravity of 1.77 (20°C), a viscosity of 186 cps (40°C), and a refractive index of 1.3465 (20°C), and the values of l, m, and n are l≒2.85 and m≒
2.5, n=3. Example 5 0.26 mol of 1,1,1,3,3,3-hexafluoroisopropanol and 1.26 mol of 1,1,3-trihydroperfluoropropanol and 1,1,5
- Using a mixture of 0.54 mol of trihydroperfluoropentanol and 89 g of phosphonitrile chloride tetramer, reaction, post-treatment, and distillation were carried out according to Example 1, and an oily substance with a boiling point of 155 to 170°C/0.05 mmHg was separated. . This liquid has a specific gravity of 1.78 (20
), viscosity 180 cps (40°C), refractive index 1.3460 (20°C), and values of n=4, m≒1.35, and l≒1.1. Example 6 In a toluene solution of 89 g of phosphonitrile chloride (n = 4, 5, 6 ratios are 67.5%, 20%, 10%), 0.07 mol of 1,1,5-trihydroperfluoropentanol and 1, 0.19 mol of 1,7-trihydroperfluoroheptanol and sodium
After reacting alcoholate prepared from 0.26 mol, reacting with 1.8 mol of sodium 1,1,1,3,3,3-hexafluoroisopropoxide, the liquid obtained had a viscosity of 250 cps (40°C) and a specific gravity of 1.80 ( 20℃),
Refractive index 1.3477 (20℃), n=4.3, l=7.5, m=2.8
has the value of Example 7 Fluorophosphonitrite (A) was injected into a direct-coupled oil rotary vacuum pump that had been thoroughly cleaned with solvent, and the oil temperature, degree of vacuum, and power consumption were measured at startup and during continuous operation for one week. Ta. The results are shown in Tables 1 and 2, respectively. From these results, it was confirmed that there were no problems as an oil rotary vacuum pump oil.

【table】

[Table] Example 8 Fluorophosphonitrite (B) was injected into a direct-coupled oil rotary vacuum pump that had been thoroughly cleaned with solvent, and a test plasma generator using a mixed gas of Freon-14 and hydrogen was operated. I did it. No abnormality was observed in the motor current value during 30 days of operation.
When the oil was removed and examined, a small amount of reddish brown liquid was found on the top of the oil, but the viscosity was low at 40℃.
The viscosity of new oil is 240cps at the same temperature.
Almost no changes were observed compared to . No difference was observed in the IR, NMR, and MS (mass spectrum) analysis results of the oil after use compared to the spectrum of the oil before use. The reddish-brown liquid appears to have originated from plasma or the material to be etched, but it did not interfere with the operation of the rotary pump. Comparative Example 1 A commercially available mineral oil-based vacuum oil (Aceback 68, kinematic viscosity 68 cst at 40°C) was injected into an oil rotary vacuum pump, and a test plasma generator using a mixed gas of Freon-14 and hydrogen was operated. Summer. After 10 days, the motor current showed an abnormality, so
When the operation was stopped and the oil was checked, sludge had formed and the viscosity at 40°C was 160 cst. Example 9 A direct-coupled oil rotary vacuum pump (pumping speed 960/min, oil volume 2.2
) was injected with fluorophosphonitrilate (C). After three weeks of operation, the oil was drained and examined. The oil was cloudy and some reddish-brown contaminants were observed floating on the top of the oil, but the viscosity of the oil itself was 240 cps (40 cps). ℃), there is almost no change compared to 250 cps (40℃) of new oil, and IR, NMR, MS
There was no difference in the results of each spectrum from those before use, and it was recognized that "fluorophosphonitrilate (C)" had extremely excellent resistance to the above-mentioned active gas. It was determined that the cloudiness and reddish-brown floating matter were caused by external contaminants such as etchings. Comparative Example 2 Commercially available mineral oil-based rotary pump oil (Neobac
ST-200), and the apparatus was operated under the conditions of Example 9. The viscosity was 78cst (40℃) before use, but after one week it was 108cst (40℃), and after 3 weeks it was 488cst.
(100℃), and it was like grease at room temperature. Example 10 (Elastomer Compatibility) When the subject substance is used as a lubricant for various mechanical devices, compatibility with the sealing material is important.
Here we will introduce Viton O-rings (V#4640 4DG-30 manufactured by Asahi Chemical), which are often used in chemical equipment, at 80°C.
Viton was immersed for 15 days in the following sample maintained at a constant temperature, and the weight change of Viton was measured. Sample name Weight change (1) Fluorophosphonitrilate (A) 4.9% (2) Hexakis (1,1,5-trihydroperfluoropentyloxy)cyclotriphosphonitrile (comparative substance) 17.1% (3) Tetrakis ( 1,1,3-trihydroperfluoropropoxytetrakis (1,1,5-trihydroperfluoropentyl (comparative substance)
7.0% oxy)cyclotetraphosphonitrile "Effects of the Invention" As described above, the present invention provides a new substance useful as a lubricating oil and a hydraulic oil, and in particular, the following points make it suitable for use as a rotary pump oil. This is what is expected. We have provided a lubricating oil that is nonflammable and highly resistant to active gases. As shown in Example 10, the fluororubber swelling property of the known fluorophosphazene oil (Japanese Unexamined Patent Publication No. 58-164698) was improved. The degree of freedom in selecting raw materials has been greatly expanded. That is,
ASLE Transaction (ASLE)
TRANSACTI-ONS) 7 = 389-397 (1964), oils with physical properties applicable as rotary pump oils are m
= 1.5 and n = 3, m = 2 (including a 1:1 mixture of m = 1 and m = 3), so even if you use it forcibly, m = 3 and m = 5 can be used. . This time, in addition to being able to use long-chain telomeric alcohols, it is also possible to use phosphonitrile tetramers or higher, and hexafluoroisopropanol, which is stable as a raw material, can be used, so there is a great deal of freedom in selecting raw materials. Expanded.

[Brief explanation of the drawing]

Figure 1 shows the IR of the substance of the present invention obtained in Example 1.
Fig. 2 is a ¹ H-NMR spectrum of the same substance, and Fig. 3 is a GC analysis diagram of the same substance. FIG. 4 shows the IR spectrum of the substance of the present invention obtained in Example 2, and FIG. 5 shows ^{the 1} H-NMR spectrum of the same substance. FIG. 6 is a ¹ H-NMR spectrum of the substance of the present invention obtained in Example 3.

Claims (1)

[Claims] 1 Mixed fluoroalkoxy cyclic phosphonitrile ester represented by the following formula () [{CF ₃ ) ₂ CHO} _l {H(CF ₂ CF ₂ ) _n CH ₂ O} _2o-l
(PN) _o ] ...() (In the formula, (PN) _o means a phosphonitrile ring,
m means a real number within the range of 1.3≦m≦2.8, n means a real number within the range of 3≦n≦4.3, and l means a real number within the range of 1≦l≦2n-1. ) 2 () in the formula (CF ₂ CF ₂ ) where _n consists of a segment with a single chain length of m=2, n is 4, and l is 1≦
The mixed fluoroalkoxy cyclic tetraphosphonitrile ester according to claim 1, which is a real number within the range of l≦2n-1. 3 A rotary pump oil whose main component is a mixed fluoroalkoxy cyclic phosphonitrile ester represented by the following formula (). [{CF ₃ ) ₂ CHO} _l {H(CF ₂ CF ₂ ) _n CH ₂ O} _2o-l
(PN) _o ] ...() (In the formula, (PN) _o means a phosphonitrile ring,
m means a real number within the range of 1.3≦m≦2.8, n means a real number within the range of 3≦n≦4.3, and l means a real number within the range of 1≦l≦2n-1. ) 4 In the formula (CF ₂ CF ₂ ), _n consists of a segment with a single chain length of m=2, n is 4, and l is 1≦
The rotary pump oil according to claim 3, which has a real value within the range of l≦2n-1.