JP2669992B2 - Silicone grease composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicone grease composition, and more particularly to a silicone grease composition having excellent lubricating properties without using a thickener.

[0002]

BACKGROUND ART Silicone grease is made of a silicone oil and thickening agent is a basic, (hereinafter abbreviated as M units) diorganopolysiloxane, R ³ ₃ SiO _1/2 units for this , R ₂ SiO units (hereinafter D
Unit) and a SiO ₂ unit (hereinafter abbreviated as Q unit) and an organopolysiloxane composition and a thickener (see JP-B-53-776), diorganopolysiloxane, M unit, RSiO _3/2 unit price (hereinafter T
Abbreviated as “unit”) and a Q unit, and an organopolysiloxane composition and a thickener (Japanese Patent Publication No. 60-452).
No. 40), a branched organopolysiloxane, an organopolysiloxane composition composed of M units and Q units and a thickener (see Japanese Patent Publication No. 3-76359).

[0003]

However, the MDQ unit,
An organopolysiloxane composition comprising MTQ units and MQ units dissolves in a diorganopolysiloxane or a branched organopolysiloxane, and therefore aluminum, lead, zinc, manganese, lithium, sodium and sodium are required to make the composition a grease. , Potassium, calcium, barium, strontium, copper, mercury, bismuth, chromium,
Inert oxides of fine particles of inorganic elements such as metal soaps of fatty acids having at least 8 carbon atoms, including metals such as iron and nickel, silica, alumina, iron oxide, titanium oxide, zinc oxide, glass fiber, clay, etc. It is essential to add thickeners such as boron, aryl urea, phthalocyanine, indusulene, polytetrafluoroethylene powder, graphite and carbon black. For this reason, there has been proposed a composition comprising an organopolysiloxane containing no thickening agent and an organopolysilsesquioxane represented by M units (see Japanese Patent Publication No. 2-22797). Since the thickener is not an essential component, the thickening effect is weak, and only a thick (soft) grease is given. Therefore, it is necessary to add a thickener to obtain a stable consistency.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a silicone grease composition which has solved such disadvantages, which is represented by A) the general formula

Embedded image (Where R ¹ is a saturated monovalent hydrocarbon group having 4 to 18 carbon atoms;
² is a monovalent hydrocarbon group selected from an alkyl group having 1 to 12 carbon atoms, an alkenyl group and an unsubstituted or substituted aryl group, a and b are 0 or 1, m is 0 to 500, and n is 5 to 50.
0, m + n is a positive number of 5 to 500), R ¹ is 10 to 50 mol% of all the substituents, and the viscosity at 25 ° C. is 50 to 5,000.
100 parts by weight of the long chain alkyl-modified silicone oil is _{^{cS, B) R 3 3 SiO}} 1/2 units (R ³ comprises an alkyl group, an alkenyl group, a group selected from aryl group) and SiO ₂ units, R ³ ₃ 20/300 parts by weight of a powdery organopolysiloxane having a molar ratio of ₃ SiO _1/2 units to SiO ₂ units of 0.5 to 0.95.

That is, as a result of various investigations by the present inventors to develop a silicone grease composition capable of forming a good tacky grease without the addition of a thickener, the organopolysiloxane to be used here is generally described above. When the long-chain alkyl-modified silicone oil represented by the formula (1) is added, and the organopolysiloxane composition comprising M units and Q units added to the oil is made into a powder form, these are mixed and kneaded with a three-roll mill. It has been found that this can be a tacky grease having good lubricity without adding a thickener, and that the production time can be significantly reduced and that the cost can be reduced. Completed.
This will be described in detail below.

[0006]

The present invention relates to a silicone grease composition, which comprises: A) 100 parts by weight of a long-chain alkyl-modified silicone oil represented by the aforementioned general formula (1);
B) Consists of M units and Q units, and the M / Q molar ratio is 0.5.
The composition comprises 20 to 300 parts by weight of a powdery organopolysiloxane having a viscosity of 0.95 to 0.95 . Since it gives grease, silicone green
It is possible to obtain the composition with high efficiency and at low cost.

As described above, the silicone grease composition of the present invention comprises A) a long-chain alkyl-modified silicone oil represented by the general formula (1), and B) M units and Q units, and a molar ratio of M / Q. Is mixed with a powdery organopolysiloxane of 0.5 to 0.95. The long-chain alkyl-modified silicone oil as the component A) constituting this silicone grease composition is represented by the general formula (1), and R ¹ is a butyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group. A saturated monovalent hydrocarbon group having 4 to 18, preferably 6 to 14 carbon atoms such as decyl group, R ² is an alkyl group such as methyl group, ethyl group, propyl group, butyl group, octyl group, or vinyl group , An alkenyl group such as an allyl group, a phenyl group, a monovalent hydrocarbon group having 1 to 12 carbon atoms selected from an aryl group such as a tolyl group, preferably a methyl group, and a and b are 0 or 1 Here, m is 0 to 500, n is 5 to 500, and m + n is a positive number of 5 to 500.

The long-chain alkyl-modified silicone oil is as follows:

Embedded image

Embedded image

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Embedded image However, if the viscosity at 25 ° C is less than 50 cS, the resulting grease will have poor stability,
Since those with a viscosity higher than 5,000 cS are very difficult to manufacture, this requires that the viscosity at 25 ° C be in the range of 50 to 5,000 cS, but this preferred range is 100 ~ 2,000 cS

The component (B) which constitutes the silicone grease composition of the present invention is an MQ siloxane comprising M units and Q units, which has an M / Q molar ratio of 0.5.
If it is less than 0.95, it is difficult to manufacture and powdering becomes difficult, and 0.95
If it is larger than this, sufficient adhesiveness cannot be obtained, so that it is necessary to set the molar ratio of M / Q to 0.5 to 0.95.

However, since the MQ siloxane itself does not dissolve in the long-chain alkyl-modified silicone oil as the component A), when the mixture is solvent stripped, it is separated into two layers of the long-chain alkyl-modified silicone oil and the MQ siloxane. However, even if it is made into a grease, it is not possible to obtain a grease with stable adhesive strength and consistency, but this MQ siloxane is powdered and added to a long-chain alkyl-modified silicone oil. It has been discovered by the present inventors that, when kneaded with a roll or the like, a grease having excellent lubricating adhesiveness can be obtained without adding a thickener, and it is necessary to supply the grease in a powder form. It is said that

Therefore, it is necessary to mix the M unit silane and the Q unit silane and then hydrolyze and polycondense the MQ siloxane to obtain a powdery solid. If the amount of this powdery MQ siloxane is less than 20 parts by weight with respect to 100 parts by weight of the long-chain alkyl-modified silicone oil as the component A), the grease obtained will have a weak adhesive force and a large consistency and softness. As a result, the grease cannot achieve its purpose. If it is more than 300 parts by weight, it has a low consistency (hard) and is not suitable for the intended use. A preferred range is 30 to 270 parts by weight.

The silicone grease composition of the present invention is a mixture of a predetermined amount of the above long chain alkyl modified silicone oil as the component A) and a powdery MQ siloxane as the component B). some, but this compound planetary - were mixed well by a mixer such as a three roller type - - mixer benefit again kneaded like Le when glyceraldehyde - becomes a scan-like material, without adding thickener this thing lubricity even, viscosity adhesion of excellent grease - those having the advantage of being able to scan.

If desired, a rust preventive or an antioxidant may be added to the silicone grease composition. As the rust preventive, benzotriazole or the like may be added.
Antioxidants 4.4 ^'- methylenebis-2,6
Illustrative examples include di-tert-butylphenol. Incidentally, the silicone - Nguri - silico made of scan composition -
Nguri - scan is obtained stable torque value, the torque value down rate after the running is small, so that superior to lubricity, for example, Russia - Tali - axis volume, bearing Fi - ring up lubricant door - As a damper for hinges, as a lubricant for autometing lines and robot arms
It can be used for

Example Next, examples and comparative examples of the present invention will be described.
The parts in the examples are parts by weight, and the viscosity is measured at 25 ° C.
The grease properties in the examples are as follows.
It shows the measured value by. [Measurement of physical properties] Measured according to JIS-K-2220
Was. [Adhesive strength] Using a 4mmφ × 8mmL shaft and bearing,
It was measured at Alance 35 μm. [Lubricity] Using a high-speed four-ball testing machine, 1,500 rpm,
40 kg load, 1 minute time, wear by 1/2 inch steel ball
Indicated by the scar diameter, the smaller the wear scar diameter, the more lubricious
Show the good things.

Examples 1 to 4 The long-chain alkyl group is a C ₁₄ tetradecyl group and its content is 37.5 mol%,

Embedded image Table 1 shows MQ resin powder having a molar ratio of (CH ₃ ) ₃ SiO _1/2 units to SiO ₂ units of 0.85 in 100 parts of a long-chain alkyl-modified silicone oil having a viscosity of 400 cS. was added in the amounts shown, planetary - mixers - After mixing well, the three b - kneaded Le to silico - Nguri - nest composition, glyceryl the ones - was examined scan characteristics, Table 2 The results as described above were obtained.

Example 5 The long-chain alkyl group is a C ₁₆ hexadecyl group and the content thereof is
25 mol%

Embedded image In 100 parts of a long chain alkyl-modified silicone oil having a viscosity of 450 cS, (CH ₃ ) ₃ SiO _1/2 units and S
MQ resin powder with a molar ratio of 0.67 to iO ₂ unit
150 parts were added and treated in the same manner as in Example 1 to prepare a silicone grease composition. The grease properties of the composition were examined, and the results shown in Table 2 were obtained.

Example 6 The long-chain alkyl group is a C ₁₀ decyl group and its content is 35 mol%.

Embedded image In 100 parts of a long chain alkyl-modified silicone oil having a viscosity of 2,000 cS, (CH ₂ = CH) (CH ₃ ) ₂
When 150 parts of MQ resin powder having a molar ratio of SiO _1/2 unit to SiO ₂ unit of 0.85 was added and treated in the same manner as in Example 1, a silicone grease composition was prepared, and the grease characteristics of this were examined. The results shown in Table 2 were obtained.

Example 7 The long-chain alkyl group is a C ₈ octyl group and its content is 50 mol%.

[Formula 10] In 100 parts of a long-chain alkyl-modified silicone oil having a viscosity of 100 cS, (CH ₃ ) ₃ SiO _1/2 units and S
MQ resin powder with a molar ratio of 0.74 to iO ₂ unit
150 parts were added and treated in the same manner as in Example 1 to prepare a silicone grease composition. The grease properties of the composition were examined, and the results shown in Table 2 were obtained.

COMPARATIVE EXAMPLE 1 To 100 parts of dimethyl silicone oil having a viscosity of 500 cS, 67 parts of MQ resin powder having a molar ratio of (CH ₃ ) ₃ SiO _1/2 units to SiO ₂ units of 0.85 was added. planetary - mixer - mixed well three from at Russia -
MQ resin powder was dissolved in dimethylsilicone oil and turned into an oily form, and silica 25 surface-treated with (C ₆ H ₅ ) ₂ Si (OH) ₂ was added. The resulting mixture was kneaded with three rolls to obtain grease. The grease characteristics of the grease were examined. The results shown in Table 2 were obtained.

Methyl phenyl silicone oil 10 having a viscosity of 3,000 cS and a phenyl group content of 5 mol%.
0 parts, (CH _{3) 3} SiO _1/2 units and molar ratio of SiO ₂ units of MQ Rejinpauda -107 parts 0.67 In addition, planetary - mixers - were mixed well, three B - After kneading, the MQ resin powder was dissolved in methylphenylsilicone oil, and 25 parts of silica surface-treated with (C ₆ H ₅ ) ₂ Si (OH) ₂ was added to this and the mixture was mixed again. Grease was obtained by kneading with this roll, and the grease characteristics of the grease were examined. The results shown in Table 2 were obtained.

Comparative Example 3 To 100 parts of methylphenylsilicone oil having a viscosity of 1,500 cS and a phenyl group content of 5 mol%, (C
H _{3) 3} SiO _1/2 units and molar ratio of SiO ₂ units of MQ Rejinpauda -91 parts of 0.85 was added, plastics <br/> Netari - Mixer - three After well mixed in Russia - Le When kneaded, the MQ resin powder was dissolved in methylphenylsilicone oil, so 31 parts of the same silica as that used in Comparative Example 1 was added and kneaded again with three rolls. Since a grease was obtained, the grease characteristics of this product were examined, and the results shown in Table 2 were obtained.

[0022]

[Table 1]

[Table 2]

[0023] (Experimental Evaluation of Results) is sufficiently even without using a thickening agent any grease that of Example - maintains a focal, which has been proven from the fact oil separation is small . Also, this one is stable
The obtained torque value is stable, the down rate of the torque value after running is small and stable, and this also has a small wear mark,
Good lubricity was confirmed. However, it was confirmed that all of the comparative examples could not maintain the grease state without using a thickener, and these greases had relatively high torque values. However , the down ratio after running was large, and the wear marks were large, indicating poor lubricity.

[0024]

Industrial Applicability The present invention relates to a silicone grease composition, which comprises, as described above, A) a long-chain alkyl-modified silicone oil represented by the general formula (1):
0 parts by weight and B) R ³ ₃ SiO _1/2 unit (M unit) and SiO
_It consists of ₂ units (Q units) and the molar ratio of M / Q is 0.5-0.
95 is a powdery organopolysiloxane 20-300
The long-chain alkyl-modified silicone oil and powdered MQ
When kneaded with an organopolysiloxane using a three-roll mill or the like, a grease having good lubricity and tackiness can be easily obtained without adding a thickening agent. Therefore, according to this, a silicone grease composition can be easily prepared in a short time, and It offers the advantage of being cheap to obtain.

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) References Japanese Patent Publication No. 53-776 (JP, B2) Japanese Publication No. 2-22797 (JP, B2)

Claims (2)

(57) [Claims] 1. A) General formula: (Here, R ¹ is a saturated monovalent hydrocarbon group having 4 to 18 carbon atoms, R ^1
2 is a monovalent hydrocarbon group selected from an alkyl group having 1 to 12 carbon atoms, an alkenyl group and an unsubstituted or substituted aryl group, a and b are 0 or 1, m is 0 to 500, and n is 5 to 50.
0, m + n are positive numbers of 5 to 500), R ¹ is 10 to 50 mol% of all the substituents, and the viscosity at 25 ° C. is 50 to 5,000.
100 parts by weight of the long chain alkyl-modified silicone oil is _{^{cS, B) R 3 3 SiO}} 1/2 units (R ³ comprises an alkyl group, an alkenyl group, a group selected from aryl group) and SiO ₂ Prefecture, R ³ ₃ The molar ratio of SiO _1/2 units to SiO ₂ units is 0.
5 to 0.95 powdered organopolysiloxane 20
~ 300 parts by weight, and a silicone grease composition. 2. The silicone grease composition according to claim 1, wherein R ² is a methyl group.