Alkylated diphenyl ether compound and lubricating oil containing said compound

Abstract

A compound of the formula (2) ##STR00001##
wherein R.sup.3 and R.sup.4 are the same or different and are a branched hydrocarbon group having 10 to 26 carbon atoms, 42 to 100 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary, m and n are each a real number of at least zero, and 2.0m+n3.0.

Claims

1. A compound of the formula (2) ##STR00012## wherein R.sup.3 and R.sup.4 are the same or different and are a branched hydrocarbon group having 10 to 26 carbon atoms, 42 to 100 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary, m and n are each a real number of at least zero, and 2.0m+n3.0; and the compound of the formula (2) contains monoalkylated diphenyl ether in an amount of about 0.1 to 20 mole %.

2. A compound of the formula (2) obtained by an addition reaction of diphenyl ether and a branched -olefin of the formula (1) or its corresponding branched alkyl halide ##STR00013## wherein R.sup.1 and R.sup.2 are the same or different and are a hydrocarbon group having 4 to 12 carbon atoms, R.sup.3 and R.sup.4 are the same or different and are a branched hydrocarbon group having 10 to 26 carbon atoms, 42 to 100 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary, m and n are each a real number of at least zero, and 2.0m+n3.0; and the compound of the formula (2) contains monoalkylated diphenyl ether in an amount of about 0.1 to 20 mole %.

3. A compound of the formula (2) obtained by an addition reaction of diphenyl ether derivative of the formula (3) and a branched -olefin of the formula (1) or its corresponding branched alkyl halide ##STR00014## wherein R.sup.1 and R.sup.2 are the same or different and are a hydrocarbon group having 4 to 12 carbon atoms, R.sup.3 and R.sup.4 are the same or different and are a branched hydrocarbon group having 10 to 26 carbon atoms, 42 to 100 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary, m and n are each a real number of at least zero, and 2.0m+n3.0; and the compound of the formula (2) contains monoalkylated diphenyl ether in an amount of about 0.1 to 20 mole %.

4. A compound of the formula (2) as defined claim 1 wherein a ratio of the carbon at benzyl position being quaternary is 45 to 95 mole %.

5. A compound of the formula (2) as defined claim 1 wherein 50 to 90 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary.

6. A compound of the formula (2) as defined in claim 1 wherein 50 to 65 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary.

7. A compound of the formula (2) as defined in claim 1 wherein R.sup.3 and R.sup.4 are each 1-butyl-1-methylheptyl, 1-methyl-1-pentyloctyl, 1-hexyl-1-methylnonyl, 1-heptyl-1-methyldecyl, 1-methyl-1-octylundecyl or 1-decyl-1-methyltridecyl.

8. A compound of the formula (2) as defined in claim 1 wherein 2.0m+n2.94.

9. A lubricating oil which is usable at high temperature containing a compound of the formula (2) ##STR00015## wherein R.sup.3 and R.sup.4 are the same or different and are a branched hydrocarbon group having 10 to 26 carbon atoms, 42 to 100 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary, m and n are each a real number of at least zero, and 2.0m+n3.0; and the compound of the formula (2) contains monoalkylated diphenyl ether in an amount of about 0.1 to 20 mole %.

10. A compound of the formula (2) as defined in claim 2 wherein a ratio of the carbon at benzyl position being quaternary is 45 to 95 mole %.

11. A compound of the formula (2) as defined in claim 2 wherein 50 to 90 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary.

12. A compound of the formula (2) as defined in claim 2 wherein 50 to 65 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary.

13. A compound of the formula (2) as defined in claim 2 wherein R.sup.3 and R.sup.4 are each 1-butyl-1-methylheptyl, 1-methyl-1-pentyl octyl, 1-hexyl-1-methylnonyl, 1-heptyl-1-methyldecyl, 1-methyl-1-octylundecyl or 1-decyl-1-methyltridecyl.

14. A compound of the formula (2) as defined in claim 2 wherein 2.0m+n2.94.

15. A compound of the formula (2) as defined in claim 3 wherein a ratio of the carbon at benzyl position being quaternary is 45 to 95 mole %.

16. A compound of the formula (2) as defined in claim 3 wherein 50 to 90 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary.

17. A compound of the formula (2) as defined in claim 3 wherein 50 to 65 mole % of the benzylic carbons of each R.sup.3 and R.sup.4 are quaternary.

18. A compound of the formula (2) as defined in claim 3 wherein R.sup.3 and R.sup.4 are each 1-butyl-1-methylheptyl, 1-methyl-1-pentyloctyl, 1-hexyl-1-methylnonyl, 1-heptyl-1-methyldecyl, 1-methyl-1-octylundecyl or 1-decyl-1-methyltridecyl.

19. A compound of the formula (2) as defined in claim 3 wherein 2.0m+n2.94.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is GPC spectrum of Compound 1.

(2) FIG. 2 is .sup.1H-NMR spectrum of Compound 1.

(3) FIG. 3 is GPC spectrum of Compound 2.

(4) FIG. 4 is .sup.1H-NMR spectrum of Compound 2.

(5) FIG. 5 is GPC spectrum of Compound 3.

(6) FIG. 6 is .sup.1H-NMR spectrum of Compound 3.

(7) FIG. 7 is GPC spectrum of Compound 4.

(8) FIG. 8 is .sup.1H-NMR spectrum of Compound 4.

(9) FIG. 9 is GPC spectrum of Compound 5.

(10) FIG. 10 is .sup.1H-NMR spectrum of Compound 5.

(11) FIG. 11 is GPC spectrum of Compound 6.

(12) FIG. 12 is .sup.1H-NMR spectrum of Compound 6.

(13) FIG. 13 is GPC spectrum of Compound 7.

(14) FIG. 14 is .sup.1H-NMR spectrum of Compound 7.

(15) FIG. 15 is GPC spectrum of Compound 8.

(16) FIG. 16 is .sup.1H-NMR spectrum of Compound 8.

(17) FIG. 17 is GPC spectrum of Compound 9.

(18) FIG. 18 is .sup.1H-NMR spectrum of Compound 9.

(19) FIG. 19 is .sup.1H-NMR spectrum of a model compound.

EXAMPLES

(20) The invention will be described in more detail with reference to the following examples and comparative examples to which, however, the invention is not limited. An alkali neutralizing agent used below is Kyoward 1000 [Mg.sub.4.5.Al.sub.2(OH).sub.13.CO.sub.3. 3.5H.sub.2O] of Kyowa Chemical Industry Co., Ltd.

Example 1

Preparation of Compound 1

(21) To a four-necked flask having 10 liter volume equipped with a stirrer, dropping funnel, thermometer and condenser were placed 2800 g (16.5 moles) of diphenyl ether and 32 g (0.24 mole) of anhydrous aluminum chloride. After dissolving anhydrous aluminum chloride with heating at 110 C., to the mixture was added dropwise 4600 g (16.5 moles) of 2-octyldodecene while maintaining the temperature at 110 C. for 4.5 hours to perform an addition reaction. After completion of dropwise addition, the mixture was stirred at 110 C. for 30 minutes, then allowed to cool to 90 C., and thereto added 300 g of alkali neutralizing agent and stirred for 30 minutes. To the mixture was added 150 g of activated clay, stirred at 90 C. for one hour and removed aluminum chloride and other acid substances by-produced by filtration at reduced pressure. Then, removing unreacted starting material and monoalkylated diphenyl ether by distillation at reduced pressure of 2.5 to 3.5 torr at 250 to 324 C., thereby 3210 g of alkyl diphenyl ether wherein dialkylated diphenyl ether was contained as a main component was obtained. The product also contained a part of monoalkylated diphenyl ether. The product (referred to as Compound 1) contained 18.2 mole % of monoalkylated diphenyl ether and alkyl addition number was 2.00 from GPC spectrum (FIG. 1) and 1H-NMR spectrum (FIG. 2). The ratio of the benzylic carbons being quaternary was 58.0 mole %.

(22) GPC

(23) Retention time of monoalkylated diphenyl ether: 41.78943.886 18.2 mole %

(24) Retention time of dialkylated diphenyl ether: 40.08341.789 56.6 mole %

(25) Retention time of trialkylated diphenyl ether: 37.59540.083 25.2 mole %

(26) .sup.1H-NMR (solvent: none, standard substance: none)

(27) Integrated value of =6.57.3 ppm is 1,

(28) integrated value of =2.83.3 ppm is 0.06,

(29) integrated value of =2.22.7 ppm is 0.09,

(30) integrated value of =0.51.9 ppm is 10.10.

(31) GPC system of Shimadzu Corp. was used. The system was as follows. CBM-20A (system controller), DGU-20A3 (online degasser for three channels), LC-20AD (liquid feed unit for high-precision analysis), SIL-20A (auto-sampler), RID-10A (refractive index detector) and SPD-20A (UV-VIS detector).

(32) In the measurement, three KF-803L columns, THF (mobile phase) and SPD-20A (detector) were used. Flow rate was 30 MPa.

(33) .sup.1H-NMR was measured by using a nuclear magnetic resonance device, JNM-ECX400 of JEOL Ltd. at 80 C. without solvent and standard substance.

(34) Chemical shift was obtained by conducting the measurement using the same compound, deuterated chloroform as solvent and TMS as standard substance. This is why peaks of deuterated chloroform overlap with those of benzene ring and precious integrated values are unavailable.

(35) The ratio of each alkyl-adducted compound such as monoalkyl-adducted compound was calculated from each peak area of GPC spectrum. In case a peak is not an independent peak, the ratio was calculated from each peak area obtained by drawing a perpendicular line from valley of neighboring two peaks.

Example 2

Preparation of Compound 2

(36) The experiment was conducted in the same manner as in Example 1 except that 1900 g (11.2 moles) of diphenyl ether, 33 g (0.25 mole) of anhydrous aluminum chloride, 4700 g (16.8 moles) of 2-octyldodecene, 320 g of alkali neutralizing agent and 160 g of activated clay were used in a four-necked flask having 10 liter volume to obtain 3640 g of alkyl diphenyl ether wherein dialkylated diphenyl ether was contained as a main component. The product (referred to as Compound 2) contained 15.9 mole % of monoalkylated diphenyl ether and alkyl addition number was 2.13 from GPC spectrum (FIG. 3) and .sup.1H-NMR spectrum (FIG. 4). The ratio of the benzylic carbons being quaternary was 57.5 mole %.

(37) GPC

(38) Retention time of monoalkylated diphenyl ether: 41.70443.643 15.9 mole %

(39) Retention time of dialkylated diphenyl ether: 40.02841.704 50.5 mole %

(40) Retention time of trialkylated diphenyl ether: 37.04340.028 33.6 mole %

(41) .sup.1H-NMR (solvent: none, standard substance: none)

(42) Integrated value of =6.57.3 ppm is 1,

(43) integrated value of =2.83.3 ppm is 0.07,

(44) integrated value of =2.22.7 ppm is 0.09,

(45) integrated value of =0.51.9 ppm is 10.93.

Example 3

Preparation of Compound 3

(46) To a four-necked flask having 2 liter volume equipped with a stirrer, dropping funnel, thermometer and condenser were placed 385 g (2.3 moles) of diphenyl ether and 6.7 g (0.05 mole) of anhydrous aluminum chloride. After dissolving anhydrous aluminum chloride with heating at 110 C., to the mixture was added dropwise 950 g (3.4 moles) of 2-octyldodecene while maintaining the temperature at 110 C. for 4.5 hours to perform an addition reaction. After completion of dropwise addition, the mixture was stirred at 110 C. for 30 minutes, then allowed to cool to 90 C., and thereto added 67 g of alkali neutralizing agent and stirred for 30 minutes. To the mixture was added 35 g of activated clay, stirred at 90 C. for one hour and removed aluminum chloride and other acid substances by-produced by filtration at reduced pressure. Then, removing unreacted starting material and monoalkylated diphenyl ether by distillation at reduced pressure of 0.1 to 0.5 torr at 250 to 324 C., thereby 800 g of alkyl diphenyl ether wherein dialkylated diphenyl ether was contained as a main component was obtained. The product (referred to as Compound 3) contained 2.1 mole % of monoalkylated diphenyl ether and alkyl addition number was 2.35 from GPC spectrum (FIG. 5) and .sup.1H-NMR spectrum (FIG. 6). The ratio of the benzylic carbons being quaternary was 52.9 mole %.

(47) GPC

(48) Retention time of monoalkylated diphenyl ether: 42.04843.696 2.1 mole %

(49) Retention time of dialkylated diphenyl ether: 40.12642.048 54.9 mole %

(50) Retention time of trialkylated diphenyl ether: 37.56240.126 43.0 mole %

(51) .sup.1H-NMR (solvent: none, standard substance: none)

(52) Integrated value of =6.57.3 ppm is 1,

(53) integrated value of =2.83.3 ppm is 0.09,

(54) integrated value of =2.22.7 ppm is 0.11,

(55) integrated value of =0.51.9 ppm is 12.42.

Example 4

Preparation of Compound 4

(56) The experiment was conducted in the same manner as in Example 3 except that 180 g (1.06 moles) of diphenyl ether, 4.2 g (0.032 mole) of anhydrous aluminum chloride, 594 g (2.12 moles) of 2-octyldodecene, 40 g of alkali neutralizing agent and 20 g of activated clay were used in a four-necked flask having 1 liter volume to obtain 490 g of alkyl diphenyl ether wherein dialkylated diphenyl ether was contained as a main component. The product (referred to as Compound 4) contained 1.3 mole % of monoalkylated diphenyl ether and alkyl addition number was 2.54 from GPC spectrum (FIG. 7) and .sup.1H-NMR spectrum (FIG. 8). The ratio of the benzylic carbons being quaternary was 57.4 mole %.

(57) GPC

(58) Retention time of monoalkylated diphenyl ether: 41.76143.395 1.3 mole %

(59) Retention time of dialkylated diphenyl ether: 39.85541.761 46.5 mole %

(60) Retention time of trialkylated diphenyl ether: 35.90739.855 52.2 mole %

(61) .sup.1H-NMR (solvent: none, standard substance: none)

(62) Integrated value of =6.57.3 ppm is 1,

(63) integrated value of =2.83.3 ppm is 0.09,

(64) integrated value of =2.22.7 ppm is 0.11,

(65) integrated value of =0.51.9 ppm is 13.74.

Example 5

Preparation of Compound 5

(66) The experiment was conducted in the same manner as in Example 3 except that 140 g (0.82 mole) of diphenyl ether, 4.8 g (0.036 mole) of anhydrous aluminum chloride, 690 g (2.46 moles) of 2-octyldodecene, 50 g of alkali neutralizing agent and 25 g of activated clay were used in a four-necked flask having 1 liter volume to obtain 630 g of alkyl diphenyl ether wherein dialkylated diphenyl ether was contained as a main component. The product (referred to as Compound 5) contained 3.9 mole % of monoalkylated diphenyl ether and alkyl addition number was 2.94 from GPC spectrum (FIG. 9) and 1H-NMR spectrum (FIG. 10). The ratio of the benzylic carbons being quaternary was 54.4 mole %.

(67) GPC

(68) Retention time of monoalkylated diphenyl ether: 41.72643.545 3.9 mole %

(69) Retention time of dialkylated diphenyl ether: 39.85541.726 12.6 mole %

(70) Retention time of trialkylated diphenyl ether: 35.51439.855 83.5 mole %

(71) .sup.1H-NMR (solvent: none, standard substance: none)

(72) Integrated value of =6.57.3 ppm is 1,

(73) integrated value of =2.83.3 ppm is 0.12,

(74) integrated value of =2.22.7 ppm is 0.14,

(75) integrated value of =0.51.9 ppm is 16.84.

Example 6

Preparation of Compound 6

(76) The experiment was conducted in the same manner as in Example 1 except that 160 g (0.94 mole) of diphenyl ether, 3.1 g (0.023 mole) of anhydrous aluminum chloride, 316 g (1.41 moles) of 2-hexyldecene, 30 g of alkali neutralizing agent and 15 g of activated clay were used in a four-necked flask having 1 liter volume to obtain 240 g of alkyl diphenyl ether wherein dialkylated diphenyl ether was contained as a main component. The product (referred to as Compound 6) contained 10.9 mole % of monoalkylated diphenyl ether and alkyl addition number was 2.23 from GPC spectrum (FIG. 11) and .sup.1H-NMR spectrum (FIG. 12). The ratio of the benzylic carbons being quaternary was 56.4 mole %.

(77) GPC

(78) Retention time of monoalkylated diphenyl ether: 42.46744.297 10.9 mole %

(79) Retention time of dialkylated diphenyl ether: 40.35642.467 73.2 mole %

(80) Retention time of trialkylated diphenyl ether: 36.36940.356 15.9 mole %

(81) .sup.1H-NMR (solvent: none, standard substance: none)

(82) Integrated value of =6.57.3 ppm is 1,

(83) integrated value of =2.83.3 ppm is 0.08,

(84) integrated value of =2.22.7 ppm is 0.09,

(85) integrated value of =0.51.9 ppm is 9.20.

Comparative Example 1

Preparation of Compound 7

(86) To the same flask used in Example 1 were placed 1600 g (9.4 moles) of diphenyl ether and 15 g (0.11 mole) of anhydrous aluminum chloride. After dissolving anhydrous aluminum chloride with heating at 110 C., to the mixture was added dropwise a mixture of 1810 g (10.8 moles) of 1-dodecene and 1810 g (9.23 moles) of 1-tetradecene under nitrogen stream while maintaining the temperature at 110 C. for 4.5 hours to perform an addition reaction. After completion of dropwise addition, the mixture was stirred at 110 C. for 30 minutes, then allowed to cool to 90 C., and thereto added 68 g of alkali neutralizing agent and stirred for 30 minutes. To the mixture was added 68 g of activated clay, stirred at 90 C. for one hour and removed aluminum chloride and other acid substances by-produced by filtration at reduced pressure. Then, removing unreacted starting material and monoalkylated diphenyl ether by distillation at reduced pressure of 3.0 to 4.0 torr at 250 to 320 C., thereby 6000 g of alkyl diphenyl ether wherein dialkylated diphenyl ether was contained as a main component was obtained. The product (referred to as Compound 7) contained 1.8 mole % of monoalkylated diphenyl ether and alkyl addition number was 2.82 from GPC spectrum (FIG. 13) and .sup.1H-NMR spectrum (FIG. 14). The ratio of the benzylic carbons being quaternary was 37.8 mole %.

(87) GPC

(88) Retention time of monoalkylated diphenyl ether: 43.76645.224 1.8 mole %

(89) Retention time of dialkylated diphenyl ether: 42.15743.766 34.2 mole %

(90) Retention time of trialkylated diphenyl ether: 37.32842.157 64.0 mole %

(91) Integrated value of =6.57.3 ppm is 1,

(92) integrated value of =2.83.3 ppm is 0.16,

(93) integrated value of =2.22.7 ppm is 0.17,

(94) integrated value of =0.51.9 ppm is 10.30.

Comparative Example 2

Preparation of Compound 8

(95) To a four-necked flask having 2 liter volume equipped with a stirrer, dropping funnel, thermometer and condenser were placed 650 g (3.8 moles) of diphenyl ether and 4.6 g (0.035 mole) of anhydrous aluminum chloride. After dissolving anhydrous aluminum chloride with heating at 110 C., to the mixture was added dropwise 650 g (2.3 moles) of 2-octyldodecene while maintaining the temperature at 110 C. for 4.5 hours to perform an addition reaction. After completion of dropwise addition, the mixture was stirred at 110 C. for 30 minutes, then allowed to cool to 90 C., and thereto added 46 g of alkali neutralizing agent and stirred for 30 minutes. To the mixture was added 23 g of activated clay, stirred at 90 C. for one hour and removed aluminum chloride and other acid substances by-produced by filtration at reduced pressure. Then, removing monoalkylated diphenyl ether by distillation at reduced pressure of 2.5 to 3.5 torr at 280 to 315 C., thereby 940 g of alkyl diphenyl ether wherein dialkylated diphenyl ether was contained as a main component was obtained. The product (referred to as Compound 8) contained 91.8 mole % of monoalkylated diphenyl ether and alkyl addition number was 1.01 from GPC spectrum (FIG. 15) and .sup.1H-NMR spectrum (FIG. 16). The ratio of the benzylic carbons being quaternary was 64.6 mole %.

(96) GPC

(97) Retention time of monoalkylated diphenyl ether: 41.27244.395 91.8 mole %

(98) Retention time of dialkylated diphenyl ether: 39.03341.272 8.2 mole %

(99) .sup.1H-NMR (solvent: none, standard substance: none)

(100) Integrated value of =6.57.3 ppm is 1,

(101) integrated value of =2.83.3 ppm is 0.02,

(102) integrated value of =2.22.7 ppm is 0.04,

(103) integrated value of =0.51.9 ppm is 4.57.

Comparative Example 3

Preparation of Compound 9

(104) To a four-necked flask having 2 liter volume equipped with a stirrer, dropping funnel, thermometer and condenser were placed 415 g (2.4 moles) of diphenyl ether and 7.2 g (0.054 mole) of anhydrous aluminum chloride. After dissolving anhydrous aluminum chloride with heating at 110 C., to the mixture was added dropwise 1020 g (3.6 moles) of 2-octyldodecene while maintaining the temperature at 110 C. for 4.5 hours to perform an addition reaction. After completion of dropwise addition, the mixture was stirred at 110 C. for 30 minutes, then allowed to cool to 90 C., and thereto added 70 g of alkali neutralizing agent and stirred for 30 minutes. To the mixture was added 35 g of activated clay, stirred at 90 C. for one hour and removed aluminum chloride and other acid substances by-produced by filtration at reduced pressure. Then, removing unreacted starting material by distillation at reduced pressure of 2.5 to 3.5 torr at 250 to 285 C., thereby 1000 g of alkyl diphenyl ether wherein monoalkylated diphenyl ether and dialkylated diphenyl ether were contained as main components was obtained. The product (referred to as Compound 9) contained 32.3 mole % of monoalkylated diphenyl ether and alkyl addition number was 1.77 from GPC spectrum (FIG. 17) and .sup.1H-NMR spectrum (FIG. 18). The ratio of the benzylic carbons being quaternary was 53.6 mole %.

(105) GPC

(106) Retention time of monoalkylated diphenyl ether: 41.46844.081 32.3 mole %

(107) Retention time of dialkylated diphenyl ether: 39.82941.468 37.9 mole %

(108) Retention time of trialkylated diphenyl ether: 35.66539.829 29.8 mole %

(109) .sup.1H-NMR (solvent: none, standard substance: none)

(110) Integrated value of =6.57.3 ppm is 1,

(111) integrated value of =2.83.3 ppm is 0.06,

(112) integrated value of =2.22.7 ppm is 0.08,

(113) integrated value of =0.51.9 ppm is 8.69.

Test Example 1

Heat Stability Test

(114) In 30-ml glass beaker was weighed 20 g of each Compounds 1 to 9. Each sample was allowed to place in a thermostatic oven of 200 C. After 10 days or 20 days, the sample was checked for weight, kinematic viscosity and acid value. Change of properties by heat stability test was evaluated based on the values measured before the test.

Test Example 2

Fluidity at Low Temperature Test

(115) Compounds 1 to 9 were checked for pour point according to JIS K2269.

Test Example 3

Lubricity Test

(116) Friction coefficient was measured under a load of 0.98N and while raising the sample temperature from 25 C. to 250 C. by Ball on Plate friction tester using SUJ2 steel as Ball and SK-5 steel as Plate.

(117) Table 1 shows the general properties, Table 2 the results of heat stability test, and Table 3 the results of lubricity test of Compounds 1 to 9.

(118) TABLE-US-00001 TABLE 1 Com- Com- Com- Com- Com- pound 1 pound 2 pound 3 pound 4 pound 5 Example 1 Example 2 Example 3 Example 4 Example 5 alkyl group branched- branched- branched- branched- branched- carbon 20 20 20 20 20 number monoalkyl 18.2 15.9 2.1 1.3 3.9 adduct (mole %) alkyl 2.00 2.13 2.35 2.54 2.94 addition mole number Properties 40 C. 141.2 151.4 180.4 217.8 277.4 kinematic viscosity (mm.sup.2/s) 100 C. 15.40 16.34 18.63 21.53 26.35 kinematic viscosity (mm.sup.2/s) viscosity 122 114 116 118 124 index pour point 42.5 42.5 40.0 42.5 40.0 ( C.) Com- Com- Com- Com- pound 6 pound 7 pound 8 pound 9 Example 6 Com. Ex. 1 Com. Ex. 2 Com. Ex. 3 alkyl group branched- 12, 14 branched- branched- carbon 16 20 20 number monoalkyl 10.9 1.8 91.8 32.3 adduct (mole %) alkyl 2.23 2.82 1.01 1.77 addition mole number Properties 40 C. 142.3 102.6 39.0 103.5 kinematic viscosity (mm.sup.2/s) 100 C. 15.82 12.60 5.921 12.46 kinematic viscosity (mm.sup.2/s) viscosity 116 116 92 113 index pour point 45.0 45.0 50 45 ( C.)

(119) Table 1 confirms Compounds 1 to 6 which are branched alkylated diphenyl ether of the present invention exhibit low pour point equal to Compound 7 which is a conventional alkylated diphenyl ether.

(120) TABLE-US-00002 TABLE 2 Com- Com- Com- Com- Com- pound 1 pound 2 pound 3 pound 4 pound 5 Example 1 Example 2 Example 3 Example 4 Example 5 evaporation loss rate (%) 200 C. 16.7 17.1 11.1 9.6 6.8 after 20 days viscosity ratio (times) 200 C. 5.4 5.6 5.4 5.2 5.0 after 20 days acid value (mgKOH/g) before exam. 0.00 0.01 0.01 0.01 0.01 200 C. 6.76 6.41 5.95 5.82 5.69 after 20 days Com- Com- Com- Com- pound 6 pound 7 pound 8 pound 9 Example 6 Com. Ex. 1 Com. Ex. 2 Com. Ex. 3 evaporation loss rate (%) 200 C. 15.6 21.5 98.2 32.4 after 20 days Viscosity ratio (times) 200 C. 5.3 9.0 impossible 11.6 after 20 days to measure acid value (mgKOH/g) before exam. 0.01 0.01 0.01 0.01 200 C. 6.10 8.20 impossible 8.01 after 20 days to measure

(121) From the results of Table 2, it is confirmed that Compounds 1 to 6 which are branched alkylated diphenyl ether of the present invention exhibit low evaporation loss rate, low viscosity ratio and low in increase of acid value compared with Compound 7 which is known as a lubricant for high temperature, and Compound 9 in which alkyl addition number is less than 2. Compound 8 which was composed almost by branched-monoalkylated diphenyl ether is high in evaporation loss and only sludge remained after heat stability test. Thus, it is impossible to measure kinematic viscosity and acid value of Compound 8.

(122) TABLE-US-00003 TABLE 3 Com- Com- Com- Com- Com- pound 1 pound 2 pound 3 pound 4 pound 5 Example 1 Example 2 Example 3 Example 4 Example 5 friction 0.1625 0.1643 0.1672 0.1648 0.1669 coefficient (150 C.) Com- Com- Com- Com- pound 6 pound 7 pound 8 pound 9 Example 6 Com. Ex. 1 Com. Ex. 2 Com. Ex. 3 friction 0.1660 0.1723 0.1702 0.1695 coefficient (150 C.)

(123) Table 3 confirms Compounds 1 to 6 which are branched alkylated diphenyl ether of the present invention exhibit low friction coefficient and are suitable for various lubricants compared with Compound 7 which is a conventional alkylated diphenyl ether.

(124) From the above, branched alkylated diphenyl ether of the present invention exhibits fluidity at low temperature equal to a conventionally well-known and practically used alkylated diphenyl ether.

(125) Further, the present compound is low in evaporation amount in heat stability test and is suppressed in increase of acid value compared with a conventional alkylated diphenyl ether and conventional monoalkyl addition product which are widely used as a base oil for a lubricant for high temperature and heat-resistant grease.

(126) The base oil for a lubricant for high temperature and heat-resistant grease is most required to be suppressed in increase of acid value. Therefore, the present compound is confirmed to be excellent in heat resistance compared with a conventional alkylated diphenyl ether.

INDUSTRIAL APPLICABILITY

(127) The present compound and composition are not only usable as a base oil for various lubricants such as bearing oil, fluid bearing oil, oil-impregnated bearing oil, oil-impregnated plastics oil, gear oil, engine oil, gas turbine oil, automatic transmission fluid, vacuum pump oil, other machine oil and hydraulic fluid, but also usable as a base oil for grease. Further, the present compound can be added to or used conjointly with other synthetic base oil, and is suitable to expand design width of lubricants. In addition, the present compound is not only usable as lubricants but also as plasticizer, refrigerating oil or the like.