Synthetic saturated oils, and their production and use

Synthetic saturated oils useful as materials for lubricating oils and cosmetics and prepared by hydrogenation of low molecular weight polyisoprene having the 1,4 structure of at least 70% in the main chains and a number average molecular weight of about 150 to 3,000.

BACKGROUND AND SUMMARY OF THE INVENTION 
The present invention relates to synthetic saturated oils, and their 
production and use. More particularly, it relates to novel synthetic 
saturated oils, their production from low molecular weight polyisoprene 
and compositions comprising them. 
As lubricating oils, there are known petroleum lubricating oils, synthetic 
lubricating oils, fatty oils, etc. For the practical use, these oils are 
usually blended with various additives for improving their properties such 
as viscosity index improvers, flow point depressants, anti-corrosive 
agents and carbonization inhibitors. On lubricating oils used for the 
engines of jet planes, no lowering of physical properties between the two 
extremes of temperature is required. In case of lubricating oils for 
precision machines such as watches, a high viscosity index and a low flow 
point are considered as important. Automatic change gears also require 
high-quality lubricating oils. As lubricating oils meeting these 
requirements, there are proposed some synthetic oils. An example of them 
is oils obtained by polymerization of .alpha.-olefins using Lewis acid 
(e.g. aluminum chloride, aluminum bromide) as a catalyst. During the 
polymerization, however, isomerization takes place so as to change the 
branching of the polymers, thus giving no polymer having a high viscosity 
index. Another example is oils obtained by polymerization of 
.alpha.-olefins using a coordination anionic polymerization catalyst. 
These oils indicate usually a viscosity index of more than 130, a flash 
point of higher than 210.degree. C and a flow point of lower than 
-50.degree. C. However, with such flow point, they can not pass, for 
instance, the standards for hydraulic oils for airplanes under the 
American Military Standards (hereinafter referred to as "MIL") H-83282 and 
the standards for jet engine oils under MIL H-7807. In order to meet these 
standards, there is proposed a method for producing lubricating oils by 
polymerizing .alpha.-olefins having not less than 5 carbon atoms (e.g. 
octene-1, decene-1) in the presence of a catalyst composition comprising 
aluminum chloride and lithium aluminum hydride, followed by fractional 
distillation and hydrogenation. While the thus obtained saturated oils 
pass the said standards, there is still a demand to lubricating oils 
having a higher viscosity index. 
On the other hand, there are known various synthetic oils for cosmetics 
such as liquid paraffin, glycerol and polyethylene glycol. However, these 
synthetic oils are inferior to squalene, which results from purification 
of shark oil, in penetration and absorption into the skin of human body. 
Squalene has the structure corresponding to the 1,4 polymerization product 
of isoprene, all the double bonds present therein having the trans 
configuration. Because of the presence of many double bonds, squalene is 
apt to be oxidized with air, whereby an offensive odor is generated and 
sometimes harmful substances to human body are produced. This drawback can 
be overcome by subjecting squalene to hydrogenation so as to make 
unsaturation degree of zero. The resulting hydrogenation product, i.e. 
squalene, is superior in weathering resistance and penetration into and 
non-toxicity to the skin of the human body. Since, however, squalene is a 
product isolated from sharks, it has become expensive with the reduction 
in the catch of sharks. Thus, the appearance of a synthetic oil comparable 
to squalene or squalene in various favorable properties in the use for 
cosmetics has been in high demand. 
In order to provide synthetic oils suitable for various uses including 
lubricating oils and cosmetics, various attempts have been made up to the 
present time. Some of them are disclosed in Japanese Patent Publication 
(examined) No. 35,984/1974 Japanese Patent Publication (unexamined) Nos. 
85,243/1974, 117,413/1974 and 133,302/1974, etc. 
In Japanese Patent Publication (examined) No. 35,984/1974, the method 
comprises heat-polymerization of isoprene in the presence of a solid acid 
catalyst, and the isoprene may polymerize not in the straight form (i.e. 
1,4 polymerization) but in the branched forms (e.g. cyclic polymerization, 
3,4 polymerization, 1,2 polymerization). The polymerized isoprenes thus 
obtained have the structure in which an isopropenyl group, a vinyl group 
and a six-membered ring are linked to the side chains, and therefore they 
have a higher viscosity and a poorer flowing property than do the oils 
resulting from hydrogenation of natural straight terpenes. 
In Japanese Patent Publication (unexamined) No. 85/243/1974, synthetic oils 
are produced by hydrogenation of low molecular weight polymers resulting 
from the polymerization of olefins having 4 carbon atoms such as 
isobutylene, butadiene and butene-1. The oils thus obtained have a high 
viscosity even if their molecular weight is low and are inferior to 
natural oils in flowing property. 
Japanese Patent Publication (unexamined) Nos. 117,413/1974 and 133,302/1974 
disclose a method wherein squalane is synthesized by coupling geranyl 
acetone and hexahydropseudoionone, followed by dehydration and 
hydrogenation. The produced oils have a flowing property close to that of 
natural squalene. However, this method is disadvantageous in requiring not 
only expensive starting materials (e.g. geranyl acetone and 
hexahydropseudoionone) but also many reaction stages (i.e. coupling, 
dehydration and hydrogenation). 
As the result of an extensive study, it has now been found that 
hydrogenation of certain low molecular weight polyisoprene affords 
synthetic saturated oils, of which fractional distillation products have a 
wide variety of flow characteristics suitable for various uses including 
lubricating oils and cosmetics and some of them are quire similar to 
squalene in physical properties. 
According to the present invention, synthetic saturated oils are produced 
by hydrogenation of low molecular weight polyisoprene having the 1,4 
structure of at least 70% in the main chains and a number average 
molecular weight of about 150 to 3,000. 
The starting material in the method of this invention is low molecular 
weight polyisoprene as defined above. When the 1,4 structure in the main 
chains is less than 70%, the resulting hydrogenation product can hardly 
flow or does not have a low viscosity. In general, the use of low 
molecular weight polyisoprene having a higher content of 1,4 structure 
affords a hydrogenation product of lower viscosity. Also, the use of the 
one having a higher content of cis structure gives a hydrogenation product 
of lower viscosity. 
The low molecular weight polyisoprene suitable as the starting material may 
be produced by conventional procedures. For instance, such polyisoprene is 
obtainable by polymerization of isoprene in the presence of an 
.alpha.-olefin using a catalyst composition comprising an organometallic 
compound and a nickel compound with or without an electron donor as 
described in Japanese Patent Publication (unexamined) No. 115,189/1974. 
The molecular weight of the polymer to be produced can be readily 
regulated by controlling the amounts of the .alpha.-olefin, the 
organometallic compound, the nickel compound and the electron donor. 
Further, for instance, the suitable polyisoprene may be produced by living 
polymerization of isoprene by the use of a complex comprising metallic 
lithium and naphthalene in an inert solvent such as hexane as described in 
Journal of Polymer Science, 56, 449. Furthermore, for instance, the 
suitable polyisoprene may be produced by polymerization of isoprene using 
lithium salts as described in Japanese Patent Publication (unexamined) 
Nos. 35,102/1975, 46,606/1975 and 34,382/1975. Stillmore, for instance, 
the suitable polyisoprene may be produced by polymerization of isoprene in 
the presence of a radical initiator. 
The low molecular weight polyisoprene thus produced may be separated as 
liquid polymer from the reaction mixture by a conventional separation 
procedure. For instance, the catalyst for polymerization is deactivated by 
treatment with methanol, ethanol, propanol, n-amyl alcohol, water or the 
like and then eliminated by washing with an aqueous solution of acid (e.g. 
hydrochloric acid, sulfuric acid, nitric acid, formic acid, acetic acid, 
oxalic acid). The resultant mixture is neutralized with an aqueous 
alkaline solution, washed with water and then concentrated under reduced 
pressure for removal of the solvent, whereby the liquid polymer is 
obtained. 
Hydrogenation of the liquid polymer thus obtained may be carried out by 
treatment with hydrogen in the presence of a hydrogenation catalyst, 
usually at a temperature of about 50.degree. to 350.degree. C for about 1 
to 100 hours under a hydrogen pressure of about 5 to 300 kg/cm.sup.2. The 
treatment may be carried out in the presence or absence of an inert 
solvent such as alcohols (e.g. methanol, ethanol), ketones (e.g. acetone, 
methylethylketone), aliphatic hydrocarbons (e.g. heptane, hexane, pentane, 
cyclohexane) or their mixtures. As the hydrogenation catalyst, there may 
be used any conventional one such as nickel (e.g. Raney nickel, nickel on 
diatomaceous earth, Urushibara nickel, palladium and platinum. After 
completion of the hydrogenation, the catalyst and the solvent are removed 
from the reaction mixture by usual methods, and the distillation of the 
reaction mixture under reduced pressure affords the hydrogenated product 
of the liquid polymer. 
The thus obtained hydrogenated liquid polymer, i.e. the synthetic saturated 
oil of the invention, has a broad molecular weight distribution, comprises 
polymers ranging from low molecular weight ones to high molecular weight 
ones and shows generally the following physical properties: 
Appearance: colorless, transparent, odorless; 
Boiling point: B.P. (at 760 mmHg) .gtoreq. 150.degree. C; 
Specific gravity: 0.79 .ltoreq. d.sup.20 .ltoreq. 0.92; 
Refractive index: 1.40 .ltoreq. n.sub.D.sup.20 .ltoreq. 1.50; 
Viscosity: 0.2 cp .ltoreq. .eta..sup.30.degree. C .ltoreq. 10.sup.5 cp. 
The main components in such hydrogenated liquid polymer are hydrogenated 
polyisoprenes substantially representable by the formula: 
##STR1## 
wherein R.sub.1 is hydrogen or alkyl having 1 to 8 carbon atoms, R.sub.2 
is hydrogen, ethyl or isopropyl and n is an integer of 1 to 40. When, for 
instance, the hydrogenated liquid polymer is produced by hydrogenation of 
the liquid polymer according to the method described in Japanese Patent 
Publication (unexamined) No. 115,189/1974, its major components are the 
ones represented by the formula [I] wherein R.sub.1 is hydrogen and 
R.sub.2 is ethyl or isopropyl. Further, the hydrogenated liquid polymer 
produced by hydrogenation of a liquid polymer obtained by polymerization 
of isoprene in the presence of lithium or C.sub.1 -C.sub.8 alkyl lithium 
may comprise as its major components the ones represented by the formula 
[I] wherein R.sub.1 is hydrogen or C.sub.1 -C.sub.8 alkyl and R.sub.2 is 
hydrogen. Furthermore, for instance, the hydrogenated liquid polymer 
obtained by the process described in Example 2 as hereinafter presented 
contains as the major components the ones represented by the formula [I] 
wherein R.sub.1 is hydrogen and R.sub.2 is isopropyl and, when subjected 
to rectification and gel permeation chromatography, affords the following 
substances: 
______________________________________ 
Boiling 
point 
Mole- Viscosity 
at 0.15 
Specific 
Refractive 
cular at 25.degree. C 
Torr gravity, 
index 
n weight*) (cp) (.degree. C) 
d.sup.20 
n.sub.D.sup.20 
______________________________________ 
1 182 1.2 64 0.7931 1.4387 
2 253 3.4 95 0.8003 1.4448 
3 316 8.0 143 0.8051 1.4490 
4 380 15.6 172 0.8092 1.4529 
5 450 28 195 0.8125 1.4560 
6 525 45 213 0.8160 1.4585 
7-9 670 105 230-270 
0.8208 1.4630 
10-12 840 250 280-320 
0.8263 1.4683 
______________________________________ 
Note: 
*)determined by the vapor pressure osmometry method 
The hydrogenated liquid polymer may be separated by a conventional 
procedure such as fractional distillation into the initial fraction 
(30.degree. C .ltoreq. B.P./1 mmHg .ltoreq. 150.degree. C) having a low 
viscosity, the middle fraction (150.degree. C&lt;B.P./1 mmHg .ltoreq. 
450.degree. C) having a medium viscosity and the residual matter 
(450.degree. C&lt;B.P./1 mmHg) having a high viscosity. These fractions are 
applied to various uses such as machine oils for precision machines (e.g. 
watches, measuring instruments, telephones), engine oils for automobiles 
and lubricating oils for jet planes and propeller planes depending on 
their viscosities and flash points. On these uses, they may be used alone 
or in combination with conventional additives such as viscosity index 
improvers, flow point depressants, anti-corrosive agents and carbonization 
inhibitors. 
As well known, cosmetics are generally prepared by admixing together oil 
soluble materials such as vegetable oils (e.g. beeswax, vegitable wax, 
cetyl alcohol, stearic acid, lanolin, castor oil, olive oil), mineral oils 
(e.g. paraffin, liquid paraffin, vaseline, ceresine) and animal oils (e.g. 
squalane), water soluble material such as ethanol, glycerol, propylene 
glycol, polyethylene glycol, methyl cellulose, hydroxyethyl cellulose, 
polyvinyl alcohol, polyvinyl pyrrolidone, tragecanth gum and acacia gum, 
surfactants, coloring materials such as inorganic pigments (e.g. zinc 
stearate, ultramarine, titanium oxide, talc, kaolin), organic dyes and 
natural coloring matters, antioxidants, perfumes and water. 
The hydrogenated liquid polymer obtained by this invention and the 
fractions therefrom may be used as oil soluble materials in the said 
cosmetics in the form of milky lotions, creams, stick pomades and the 
like. Since they are already hydrogenated, no deterioration in quality 
will be caused on those cosmetics.

Practical and presently preferred embodiments of the present invention are 
illustratively shown in the following Examples. 
EXAMPLE 1 
The atmosphere in a 1.5-liter stainless steel autoclave (20 kg/cm.sup.2 
proof) equipped with a stirrer was replaced by nitrogen gas. Thereafter, 
300 ml of anhydrous toluene and 136 g of anhydrous isoprene were charged 
into the autoclave under the stream of nitrogen. The mixture was cooled to 
-50.degree. C, and 4 ml of a toluene solution containing 0.1 mol/liter of 
nickel naphthenate, 4 ml of a toluene solution containing 1 mol/liter of 
ethylaluminum sesquichloride, 4 ml of a toluene solution containing 0.02 
mol/liter of triphenyl phosphine and 64 g of propylene were added thereto, 
followed by polymerization at 60.degree. C for 6 hours. The 
polymerization was stopped by adding 10 ml of a 10% solution of 
isopropanol in toluene under pressure, followed by stirring for 10 
minutes. Unreacted propylene and isoprene were purged in a draft, and the 
reaction mixture was washed for 5 hours with 800 ml of an aqueous 
hydrochloric acid solution (pH 1.6) in a 2-liter glass flask and allowed 
to stand. The aqueous layer was removed, and the oily layer was mixed with 
800 ml of an aqueous sodium hydroxide solution (pH 12) for 1 hour and 
allowed to stand. The aqueous layer was removed, and the oily layer was 
thoroughly mixed with 800 ml of ion-exchanged water for 1 hour and allowed 
to stand. The aqueous layer was removed, and the oily layer was 
concentrated under reduced pressure in a rotary evaporator. In this way, 
103 g of low molecular weight polyisoprene were obtained as a colorless, 
transparent liquor having a viscosity of 24 cp at 30.degree. C. The number 
average molecular weight was 410 on determining by means of a vapor 
pressure osmometer. The infrared analysis according to the Morero's method 
showed that the microstructure of the polymer consisted of 42% of the 
cis-1,4 structure, 35.2% of the trans-1,4 structure, 19.8% of the 3,4 
structure and 2.7% of the 1,2 structure. Further, it was confirmed that 
the value of the 3,4 structure was due to the absorption of the vinylidene 
group which resulted from the dehydrogenation of one propylene molecule 
connected to the ends of the polymer chains. Thus, more than 90% of 
isoprene was polymerized in the 1,4-polymerization form. 
Raney nickel R-200 (produced by Nikko Rikagaku Sangyo Co., Ltd.) was 
activated, followed by deaeration and dehydration, and stored in a 
Schlenk's tube replaced by nitrogen gas. To a 200-ml stainless steel 
autoclave were added 5 g of the Raney nickel, 75 ml of the above obtained 
liquid polyisoprene and 75 ml of cyclohexane, and hydrogen gas was charged 
therein from a hydrogen bomb until a pressure gauge indicated 25 
kg/cm.sup.2. The contents were heated to 150.degree. C in an oil bath 
while being mixed, and mixation was further continued at 150.degree. C 
under 25 kg/cm.sup.2 for 30 hours so as to complete the hydrogenation. 
After cooling, the pressure in the autoclave was released to atmospheric 
pressure, and the catalyst was removed centrifugally to obtain a 
colorless, transparent liquor. The liquor was concentrated under reduced 
pressure in a rotary evaporator to remove the solvent, whereby 74 ml of a 
colorless, transparent liquor having a viscosity of 35 cp at 30.degree. C 
were obtained. The liquid polyisoprene thus hydrogenated showed 
approximately the same NMR and infrared spectrum charts as those of 
squalene. On comparison of the NMR charts, the ratios represented by: 
##EQU1## 
were 0.39 and 0.40 respectively for squalene and the hydrogenated liquid 
polyisoprene. Consequently, it became clear that the hydrogenated liquid 
polyisoprene has almost the same structure as that of squalene. 
Fractional distillation of 10 g of the hydrogenated product by the use of a 
molecular distillation apparatus gave 3.5 g of the first fraction (b.p., 
lower than 120.degree. C/1 mmHg), 3.2 g of the second fraction (b.p., 
140.degree. C/1 mmHg to 250.degree. C/0.2 mmHg) and 3.3 g of the residue. 
EXAMPLE 2 
The atmosphere in a 1.5-liter stainless steel autoclave (20 kg/cm.sup.2 
proof) equipped with a stirrer was replaced by nitrogen gas. Thereafter, 
300 ml of anhydrous toluene and 136 g of anhydrous isoprene were charged 
into the autoclave under the stream of nitrogen. The mixture was cooled to 
-50.degree. C, and 4 ml of a toluene solution containing 0.1 mol/liter of 
nickel naphthenate, 4 ml of a toluene solution containing 1 mol/liter of 
ethylaluminum sesquichloride, 20 ml of a toluene solution containing 0.02 
mol/liter of triphenyl phosphine and 64 g of propylene were added thereto, 
followed by polymerization at 60.degree. C for 6 hours. The polymerization 
was stopped in the same manner as in Example 1. Removal of the catalyst 
was also carried out in the same manner as in Example 1, followed by 
concentration under reduced pressure in a rotary evaporator. In this way, 
73 g of low molecular weight polyisoprene were obtained as a colorless, 
transparent liquor having a viscosity of 983 cp at 30.degree. C. The 
number average molecular weight was 540 on determining by means of a vapor 
pressure osmometer. The infrared analysis according to the Morero's method 
showed that the microstructure of the polymer consisted of 43.6% of the 
cis-1,4 structure, 36.9% of the trans-1,4 structure, 19.0% of the 3,4 
structure and 0.5% of the vinyl structure. Further, it was confirmed that 
the 3,4 structure was due to the absorption of the vinylidene group which 
resulted from the dehydrogenation of one propylene molecule connected to 
the ends of the polymer chains. 
Hydrogenation was carried out by replacing the atmosphere in a 200-ml 
stainless steel autoclave by nitrogen gas, charging 65 ml of the above 
obtained liquid polyisoprene, 5 g of Raney nickel R-200 as activated and 
75 ml of cyclohexane into the autoclave, and mixing the contents at 
150.degree. C for 30 hours while maintaining the hydrogen pressure in the 
autoclave at 25 kg/cm.sup.2. After cooling, the catalyst was centrifugally 
removed to obtain a colorless, transparent liquor. The liquor was 
concentrated under reduced pressure in a rotary evaporator to remove the 
solvent, whereby 64 ml of a colorless, transparent liquor having a 
viscosity of 1,050 cp at 30.degree. C were obtained. The iodine value, the 
hydroxyl value and the acid value were all zero. 
EXAMPLE 3 
A rotator for a magnetic stirrer was placed in a 500-ml four-necked flask, 
and the mouths of the flask were equipped with ampoules containing 28.2 g 
of anhydrous naphthalene, 200 ml of anhydrous tetrahydrofuran, 40 ml of 
anhydrous isoprene and 1.38 g of metallic lithium, respectively. After 
completely replacing the atmosphere in the flask by nitrogen gas, the 
ampoule containing metallic lithium was opened by a magnetic hammer to 
allow the lithium to fall into the flask. Next, tetrahydrofuran and 
naphthalene were allowed to fall in the same manner as above. On mixing 
the contents in the flask at room temperature for 17 hours, a deep green 
complex of lithium-naphthalene was formed. After cooling to -70.degree. C, 
isoprene was added, and the mixture was stirred at room temperature for 2 
hours, whereby the reaction solution turned to yellow brown. The 
tetrahydrofuran was removed from the reaction solution under reduced 
pressure, and then 100 ml of anhydrous n-hexane and 100 ml of cyclohexane 
were added thereto under the stream of nitrogen gas. After cooling to 
-40.degree. C, 95 ml of isoprene were added, and polymerization was 
carried out at 50.degree. C for 3 hours. The metallic lithium was removed 
from the product, in the same manner as in Example 1, by washing the 
reaction mixture with an aqueous hydrochloric acid solution. After 
neutralization and washing with water, the separated oil layer was 
concentrated under reduced pressure in a rotary evaporator to give low 
molecular weight polyisoprene. By the analysis according to the Morero's 
method, the microstructure of the resulting polymer was found to consist 
of 85% of the cis-1,4 structure and 15% of the 3,4 structure. The 
molecular weight determined by means of a vapor pressure osmometer was 
760. 
In the same manner as in Example 1, 64 g of the thus obtained liquid 
polyisoprene was hydrogenated in a 200-ml stainless steel autoclave using 
5 g of Raney nickel R-200 and 75 ml of cyclohexane. The hydrogenation was 
carried out at 150.degree. C for 30 hours with stirring, while keeping the 
hydrogen pressure in the autoclave at 30 kg/cm.sup.2. After cooling, the 
catalyst was centrifugally removed to obtain a colorless, transparent 
liquor. The liquor was concentrated under reduced pressure in a rotary 
evaporator to obtain 63 g of a colorless and odorless, transparent liquor 
having a viscosity of 130 cp at 30.degree. C. The iodine value, the 
hydroxyl value and the acid value of the liquor were all zero. 
EXAMPLE 4 
Preparation of the catalyst, the polymerization and the after-treatment was 
carried out in the same manner as in Example 3 using 7.05 g of anhydrous 
naphthalene, 200 ml of anhydrous tetrahydrofuran, 25 ml of anhydrous 
isoprene and 0.345 g of metallic lithium to give low molecular weight 
polyisoprene. By the analysis according to the Morero's method, the 
microstructure of the obtained polymer was found to consist of 88% of the 
cis-1,4 structure and 12% of the 3,4 structure. The molecular weight 
determined by means of a vapor pressure osmometer was 2,800. 
In the same manner as in Example 1, 64 g of the liquid polyisoprene was 
hydrogenated at 150.degree. C for 30 hours using 5 g of Raney nickel R-200 
and 75 ml of cyclohexane while keeping the hydrogen pressure at 30 
kg/cm.sup.2. After cooling, the reaction mixture was centrifuged in order 
to remove the catalyst, and concentrated under reduced pressure in a 
rotary evaporator to obtain 63 g of a colorless, transparent liquor. The 
liquor was colorless and odorless and had a viscosity of 3,600 cp. The 
iodine value, the hydroxyl value and the acid value of the liquor were all 
zero. 
EXAMPLE 5 
The comparison of physical properties between squalane and the hydrogenated 
low molecular weight polyisoprene (second fraction obtained in Example 1) 
is shown in the following table: 
Table 1 
______________________________________ 
Second fraction 
in Example 1 
Squalane 
Number average molecular 
407 417 
weight 
Viscosity at 30.degree. C (cp) 
27 22 
Acid value 0 0 
Iodine value (Wijs method) 
0 0 
Hydroxyl value 0 0.2 
Odor no no 
Appearance colorless colorless, 
transparent transparent 
______________________________________ 
Cold cream containing the hydrogenated polyisoprene in Table 1 was 
formulated according to the following recipe: 
______________________________________ 
Part(s) by weight 
Liquid paraffin 20 
Beeswax 15 
Hydrogenated polyisoprene 
13 
Lanolin 5 
Isopropyl myristate 4 
Monoglyceride 3 
Polyoxyethylene sorbitan 
3 
monooleate 
Ethylene glycol 4 
Sodium hydroxide 0.1 
Water 35 
Perfume 0.5 
______________________________________ 
The cold cream thus formulated was the same as that obtained using squalene 
in place of the hydrogenated polyisoprene in color, odor, long-term 
stability, nonirritativeness, spread, stiffness and touch. 
EXAMPLE 6 
Lipstick contaiing the same hydrogenated polyisoprene as in Example 5 was 
formulated according to the following recipe: 
______________________________________ 
Part(s) by weight 
Beeswax 15 
Hydrogenated polyisoprene 
7 
G wax 3 
Carnauba wax 3 
Lanolin 5 
Castor oil 5 
Hardened cotton-seed oil 
5 
Stearyl alcohol 10 
Pigment and perfume 7 
______________________________________ 
The lipstick thus formulated exhibited the same luster and spread as those 
of the lipstick formulated using squalene in place of the hydrogenated 
polyisoprene. 
EXAMPLE 7 
Hygienic cream containing the same hydrogenated polyisoprene as in Example 
5 was formulated according to the following recipe: 
______________________________________ 
Part(s) by weight 
Hydrogenated polyisoprene 
10 
Stearic acid 8 
Palmitic acid 2 
Lanolin 3 
Stearyl alcohol 5 
Diglyceride 3 
Polyoxyethylene sorbitan 
3 
monopalmitate 
______________________________________ 
The hygienic cream thus formulated exhibited the same spread and smoothness 
as those of the hygienic cream formulated using squalene in place of the 
hydrogenated polyisoprene. 
EXAMPLE 8 
Low molecular weight polyisoprene was prepared under completely the same 
conditions of polymerization and after-treatment as in Example 1 in order 
to check the reproducibility, whereby 103 g of a colorless, transparent 
liquor having a viscosity of 18 cp at 30.degree. C were obtained. On 
determining the molecular weight by means of a vapor pressure osmometer, 
the number average molecular weight was 390. 
Hydrogenation of the liquid polyisoprene was carried out under completely 
the same conditions as in Example 1. After completion of the 
hydrogenation, the reaction mixture was cooled and the pressure was 
released to atmospheric pressure. The catalyst was centrifugally removed 
to obtain a colorless, transparent liquor. In order to remove the solvent, 
the liquor was concentrated under reduced pressure in a rotary evaporator, 
whereby 74 ml of a colorless, transparent liquor were obtained. The 
viscosity was 30 cp at 30.degree. C. The liquid polyisoprene thus 
hydrogenated exhibited almost the same NMR and infrared spectrum charts as 
those of squalene. On comparison of the NMR charts, the ratios represented 
by: 
##EQU2## 
were 0.39 and 0.40 respectively for squalene and the hydrogenated liquid 
polyisoprene. Consequently, it became clear that the hydrogenated liquid 
polyisoprene has almost the same structure as that of squalene. 
Fractional distillation of 10 g of the hydrogenated product by the use of a 
molecular distillation apparatus gave 3.1 g of the first fraction (b.p., 
lower than 190.degree. C/1 mmHg) and 6.9 g of the residue. The viscosity 
of the residue was compared with that of squalene and of the polymer of 
octene-1 as shown in Table 2. 
As seen from Table 2, the hydrogenated polyisoprene as a lubricating oil 
has a high viscosity index and is a free flowing, low viscous liquid even 
at extremely low temperatures. This means that the hydrogenated 
polyisoprene passes the standards of the lubricating oil for jet engines 
specified by the American Military Standards. Thus, the lubricating oil of 
the present invention has almost the same flowing property as that of 
squalene and is very superior as a lubricating oil for jet engines. The 
polymer of octene-1 is inferior to the lubricating oil of the present 
invention in viscosity index and flow point. Particularly, the viscosity 
at -40.degree. F of the octene-1 polymer is close to the upper limit of 
the said Standards, which clearly means that the polymer has a very poor 
viscosity performance at low temperatures. 
Table 2 
______________________________________ 
Hydro- 
Properties genated 
MIL-H 83282 poly- Polymer of 
Standard isoprene Squalane octene-1 
______________________________________ 
Viscosity, 210.degree. F (cp) 
10 4.8 4.3 
more than 3.5 
Viscosity, 100.degree. F (cp) 
32 20 20.8 
more than 16.5 
Viscosity, -40.degree. F (cp) 
420 340 2800 
less than 3000 
Viscosity index 
140 140 125 
more than 120 
Flash point (.degree. F) 
425 425 412 
more than 400 less 
Flow point (.degree. F) 
less than than -70 
less than -65 -85 -85 
______________________________________ 
Table 3 shows that the synthetic lubricating oil comprising the 
hydrogenated polyisoprene of the present invention is much superior as a 
lubricating oil for precision machines to commercially available products 
selected from those which are best as a synthetic lubricating oil for 
precision machines. 
Table 3 
______________________________________ 
Reference example 
Physical 
The residue 
Commercial 
Commercial 
Commercial 
properties 
in Example 8 
product 1 product 2 
product 3 
______________________________________ 
Flash 
point 
(.degree. C) 
218 173 211 216 
Viscosity 
52 20.7 36.5 102 
at 30.degree. C 
(cp) 
Viscosity 
140 125 134 123 
index 
Flow point 
less than -22.5 -37.5 -37.5 
(.degree. C) 
-65 
______________________________________ 
The above commercially available products are in use for public telephones, 
watches, electric power meters and various equipments and are regarded as 
important as a lubricating oil having a particularly superior viscosity 
performance at low temperatures. However, the lubricating oil of the 
present invention is much superior to those commercial products in that 
performance. For example, the oil has a viscosity of as low as 510 
centistokes even at - 40.degree. C, while those commercial products 
solidify at -37.5.degree. C. Further, the oil of the present invention has 
a viscosity index of 140, which means that the oil is superior to those 
commercial products in the viscosity performance. 
The octene-1 polymer as described for comparison in Table 2 was synthesized 
by the following method: 
In a 2,000-ml four-necked flask, 200 ml of ethyl ether were charged, and 17 
g of aluminum chloride were dissolved in the ether. Thereafter, 3.1 g of 
lithium hydride was added to prepare a catalyst, and a large proportion of 
ethyl ether was removed under reduced pressure. To the flask were added 
800 ml of octene-1 and 25 g of titanium tetrachloride, and the reaction 
was carried out at 100.degree. to 200.degree. C for 4 hours. After 
completion of the reaction, ammonia gas was blown into the reaction 
solution, and the resulting precipitates were filtered off to remove the 
catalyst. The resulting reaction solution was distilled under reduced 
pressure to remove the unreacted octene-1 and the dimers thereof. 
Hydrogenation was then carried out at 150.degree. C and at a hydrogen 
pressure of 20 kg/cm.sup.2 using Raney nickel catalyst. After the 
hydrogenation, the catalyst was removed to obtain 490 g of the oligomer. 
The content of tri- to pentamers in the oligomer was 80%. 
The invention being thus described, it will be obvious that the same may be 
varied in many ways. Such variations are not to be regarded as a departure 
from the spirit and scope of the invention, and all such modifications as 
would be obvious to one skilled in the art are intended to be included 
within the scope of the following claims.