JP2014040504A - Urea clay composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a urea clay composite that has better friction resistance and wear resistance than conventional lubricants using a silicate compound.SOLUTION: A urea clay composite includes a urea compound between layers of a laminar silicate compound.

Description

  The present invention relates to a urea clay composite containing a urea compound between layers of a silicate compound having a layered structure.

Lubricants exist between two solid surfaces that are in relative motion, physicochemical properties that reduce friction and wear on these solid surfaces, reduce power loss, and prevent seizure, fatigue damage, etc. Are classified into liquid lubricants, semi-solid lubricants, and solid lubricants according to their forms.
Conventionally used as a solid lubricant is a crystal powder having a layered structure such as graphite or molybdenum disulfide, and is expected to have an effect of lubrication by slipping an interlayer portion having a small shear strength. Is. Silicate compounds such as mica and bentonite are known as those having a layered structure that is expected to have the same effect. Interlayer compounds that are reaction products in which guest compounds such as other molecules, atoms, and ions enter these interlayer portions and react with the crystal layer (host) are also conventionally used as lubricants (for example, patents) Reference 1). Patent Document 1 reports an example in which an interlayer compound obtained by bringing a metal phosphorus chalcogenide into contact with an alkylamine or ammonium chloride and reacting it is used as a lubricant or the like.
In Patent Documents 2, 3, and 4, mechanical properties that reduce wear and friction between resin and steel under moderate PV (pressure x speed) conditions by adding and dispersing the silicate compound in the polymer. I have it.

Japanese Patent Laid-Open No. 5-125379 Japanese National Patent Publication No. 11-510835 JP 2008-63544 A Special Table 2003-517488

An object of the present invention is to provide a urea clay composite having improved friction resistance and wear performance as compared with a lubricant using a conventional silicate compound.
Another object of the present invention is to provide a lubricant composition containing the urea clay composite.
Another object of the present invention is to provide a grease composition containing the urea clay composite.
Another object of the present invention is to provide a metalworking fluid composition comprising the urea clay composite.
Another object of the present invention is to provide a plastic composition containing the urea clay composite.
Another object of the present invention is to provide a coating composition containing the urea clay composite.
Another object of the present invention is to provide a method for producing the urea clay composite.

As a result of diligent research to achieve the above object, the present inventors have included a urea compound between the layers of the layered silicate compound, thereby improving friction resistance superior to that of a lubricant using a conventional silicate compound.・ We have found that wear characteristics can be provided. The present invention has been made based on such knowledge.
That is, the present invention provides the following urea clay composite, lubricant composition containing the urea clay composite, grease composition, metalworking oil composition, plastic composition, coating composition, and method for producing the urea clay composite. provide.
1. A urea clay composite containing a urea compound between layers of a layered silicate compound.
2. The urea clay composite according to 1 above, wherein the urea compound is represented by the following formula (1).

R1-NHCONH-R2-NHCONH-R3 (1)

(In the formula, R1 and R3 may be the same or different from each other, and each represents a hydrocarbon group having 4 to 22 carbon atoms, such as an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group. R2 represents a hydrocarbon group having 6 to 36 carbon atoms.)
3. The urea clay composite according to 1 or 2 above, which is obtained by reacting by the following method (I) or (II):
(I) a method of reacting a system containing a layered silicate compound and an isocyanate with a system containing an organic amine;
(II) a method of reacting a system containing a layered silicate compound and an organic amine with a system containing an isocyanate;
(However, the isocyanate is represented by the formula OCN-R2-NCO, organic amine represented by the formula R1-NH ₂ or R3-NH ₂ (wherein, R1, R2, and R3 are as defined in claim 2 is there.)).
4). The above-mentioned 1 wherein the layered silicate compound is at least one member of the group consisting of montmorillonite, bentonite, organic bentonite, hectorite, chlorite, beidellite, vermiculite, saponite, mica, nontronite, bolconscoreite, magatite, and kenyaite. The urea clay composite of any one of -3.
5. The urea clay composite according to any one of 2 to 4, wherein the isocyanate is a diisocyanate selected from the group consisting of tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, and dimer diisocyanate.
6). Organic amines are aliphatic amines octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, nonyldecylamine, eico 6. The urea clay composite according to any one of 2 to 5 above, which is at least one selected from the group consisting of silamine, docosylamine, aromatic amine paratoluidine, aniline, naphthylamine, and alicyclic amine cyclohexylamine. .
7). The urea clay composite according to any one of 1 to 6 above, containing 0.1 to 80 parts by mass of the layered silicate compound with respect to 100 parts by mass of the urea clay composite.
8). The lubricant composition containing the urea clay composite of any one of said 1-7.
9. The grease composition containing the urea clay composite of any one of said 1-7.
10. 8. A metalworking fluid composition comprising the urea clay composite according to any one of 1 to 7 above.
11. The plastic composition containing the urea clay composite of any one of said 1-7.
12 The coating composition containing the urea clay composite of any one of said 1-7.
13. A method for producing a urea clay composite comprising the following steps (I) or (II):
(I) a step of reacting a system containing a layered silicate compound and an isocyanate with a system containing an organic amine;
(II) A step of reacting a system containing a layered silicate compound and an organic amine with a system containing an isocyanate.

  According to the present invention, the anti-friction and wear characteristics can be improved as compared with a lubricant using a conventional silicate compound. The urea clay composite of the present invention itself functions as a lubricant. Since the urea clay composite of the present invention itself has a thickening action, an excellent grease composition can be obtained without adding a thickening agent. The urea clay composite of the present invention can also be used by being included in a metalworking oil composition or the like.

Scanning electron micrographs of C8 urea composite ((a) 1000 times, (b) 7500 times, (c) 12000 times) Scanning electron micrographs of C12 urea clay composite ((a) 1000 times, (b) 7500 times, (c) 12000 times) Scanning electron micrographs of C18 urea clay composite ((a) 1000 times, (b) 7500 times, (c) 12000 times) It is a scanning electron micrograph of organic bentonite ((a) 1000 times, (b) 7500 times, (c) 12000 times). It is a chart which shows the result of having conducted the powder diffraction test result by X-ray about organic bentonite. It is a chart which shows the result of having conducted the powder diffraction test result by X-ray about C8 urea. It is a chart which shows the result of having conducted the powder diffraction test result by X-ray about C12 urea. It is a chart which shows the result of having conducted the powder diffraction test result by X-ray about C18 urea. It is a chart which shows the result of having conducted the powder diffraction test result by X-ray about C8 urea composite. It is a chart which shows the result of having conducted the powder diffraction test result by X-ray about C12 urea clay composite. It is a chart which shows the result of having conducted the powder diffraction test result by X-ray about C18 urea clay composite. It is the result of measuring the coefficient of friction over time for C8-, C12-, and C18-urea. It is the result of measuring the coefficient of friction over time for organic bentonite, C8-, C12-, and C18-urea clay composites.

  The urea clay composite of the present invention can be produced by reacting a system containing (I) a layered silicate compound and an isocyanate with a system containing an organic amine. The urea clay composite of the present invention can also be produced by reacting a system containing (II) a layered silicate compound and an organic amine with a system containing an isocyanate. Thereby, a urea compound comes to be contained between the layers of the layered silicate compound. The production method (I) is preferred. After the layered silicate compound is expanded in an organic solvent or the like and the interlayer is opened, even if a separately prepared urea compound is added, the urea compound does not enter the interlayer.

Examples of the layered silicate compound include montmorillonite, bentonite, organic bentonite, hectorite, chlorite, beidellite, vermiculite, saponite, mica, nontronite, vorconscoite, magatite, and kenyaite. Of these, organic bentonite is preferable.
Organic bentonite is obtained by modifying the crystal surface of montmorillonite by treatment with a quaternary ammonium compound such as tetraalkylammonium. Examples of the tetraalkylammonium include dimethyldioctadecylammonium, dimethyloctadecylammonium, trimethyloctadecylammonium and the like. Of these, dimethyldioctadecylammonium is preferred.

Isocyanate and organic amine react to form a urea compound. Diurea compounds are preferred. The diurea compound can be represented by, for example, the following formula (1).

R1-NHCONH-R2-NHCONH-R3 (1)

(In the formula, R1 and R3 may be the same or different from each other, and each represents a hydrocarbon group having 4 to 22 carbon atoms, such as an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group. R2 represents a hydrocarbon group having 6 to 36 carbon atoms.)

  As the isocyanate, an aromatic or alicyclic diisocyanate can be suitably used. Specific examples of the aromatic or alicyclic diisocyanate include tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, and dimer isocyanate. Diphenylmethane diisocyanate is preferred.

As the organic amine, for example, an aromatic amine, an aliphatic amine, and an alicyclic amine can be suitably used. These may be used in combination. Aliphatic amines are preferred.
Specific examples of the aromatic amine include paratoluidine, aniline, naphthylamine and the like. Specific examples of the aliphatic amine include octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, nonyldecylamine, Examples include eicosylamine and docosylamine. Specific examples of the alicyclic amine include cyclohexylamine and the like.

  As the urea compound, a diurea compound obtained from an aromatic diisocyanate and an aliphatic amine is preferable. Particularly preferred are diurea compounds in which the aromatic diisocyanate is diphenylmethane diisocyanate and the aliphatic amine is octylamine, dodecylamine or octadecylamine. More particularly, a diurea compound in which the aromatic diisocyanate is diphenylmethane diisocyanate and the aliphatic amine is octadecylamine is preferable.

In the reaction of the production method (I), an isocyanate and a layered silicate compound are added to an appropriate organic solvent, and the mixture is heated to about 25 to 50 ° C and separately heated to about 25 to 80 ° C in an organic solvent. It can be carried out by combining with the organic amine and stirring at 40-100 ° C. for 5-60 minutes.
In the reaction of production method (II), an organic amine and a layered silicate compound are added to an appropriate organic solvent, heated to about 25 to 80 ° C, and separately heated to about 25 to 80 ° C in an organic solvent. This can be done by stirring together with warm isocyanate at 40-100 ° C. for 5-60 minutes.
Isocyanate and organic amine are preferably used in an amount of 0.1 to 99 parts by weight, more preferably 50 to 90 parts by weight, based on 100 parts by weight of the urea clay composite. Most preferably, it is used in such an amount that it becomes 70 parts by mass.
The layered silicate compound is preferably used in an amount of 0.1 to 80 parts by mass, more preferably in an amount of 10 to 50 parts by mass with respect to 100 parts by mass of the urea clay composite. The amount used is preferably 30 parts by mass, and most preferably used.
Organic solvents for adding isocyanate and layered silicate compound used in production method (I), and organic solvents for adding organic amine and layered silicate compound used in production method (II) include N, N- Dimethylformamide, acetone, formamide, tetrahydrofuran, propylene carbonate, dimethyl sulfoxide and the like can be used. N, N-dimethylformamide is preferred.
The organic solvent to which the organic amine used in the production method (I) is added and the organic solvent to which the isocyanate used in the production method (II) is added may be the same as or different from the organic solvents described above. Is preferred. Specifically, N, N-dimethylformamide, acetone, formamide, tetrahydrofuran, propylene carbonate, dimethyl sulfoxide and the like can be used. N, N-dimethylformamide is preferred.

  The state of the urea clay composite of the present invention is a solid and has a crystal structure. The crystal structure can be confirmed by X-ray diffraction.

  Since the urea clay composite of the present invention itself has a lubricating action, it can be used as a solid lubricant.

The urea clay composite of the present invention can be used as a thickener for grease because the viscosity of the base oil can be increased to make it semi-solid.
The content of the urea clay composite as a thickening agent is adjusted so as to be in accordance with the use, but it is usually preferably 1 to 50% by mass based on the total mass of the grease composition. More preferably, it is -20 mass%.

As the base oil, any oil that is usually used as a base oil for grease can be used without any limitation, and mineral oil, synthetic oil, and mixed oils thereof can be used. Synthetic oils include ester-based synthetic oils, synthetic hydrocarbon oils, polyglycol-based synthetic oils, phenyl ether-based synthetic oils, silicone-based synthetic oils, and fluorine-based synthetic oils.
The kinematic viscosity of the base oil at 40 ° C. is not particularly limited, but is preferably 30 to 300 mm ² / s. More preferably, it is 50-200 mm < ² > / s, More preferably, it is 50-150 mm < ² > / s.

The grease composition of the present invention can further contain components usually used as an additive for grease. Specific examples of such additives include load-bearing additives such as zinc dialkyldithiocarbamate and zinc dialkyldithiophosphate; amine antioxidants such as alkyldiphenylamine; phenolic antioxidants such as hindered phenols; Rust preventives such as acid salts; inorganic passivating agents such as sodium nitrite; metal corrosion inhibitors typified by benzotriazole; oil-based agents typified by fatty acids, fatty acid esters and phosphate esters; And antiwear agents and extreme pressure agents represented by organic metal-based materials. The content of the additive is usually 0.5 to 5% by mass based on the total mass of the grease composition.
The grease composition of the present invention can be suitably used for lubricating general industries, automobiles, various bearings, home appliances, and the like.

  If necessary, the urea clay composite of the present invention can be made into a metalworking fluid composition by including it in a base oil together with a rust inhibitor, an antioxidant, an antifoaming agent, a surfactant and the like. The metalworking fluid composition of the present invention can be used for plastic working such as cutting, grinding, rolling, drawing, pressing, forging and the like of metal members. Examples of the metal member include low carbon steel, high-tensile steel plate, and stainless steel.

  A plastic composition can be obtained by including the urea clay composite of the present invention in a plastic resin. Examples of the plastic include olefin resin, ABS resin, styrene resin, and the like. The plastic composition of the present invention can be used for plastic parts such as gears.

  The urea clay composite of the present invention can be combined with a pigment or the like to form a coating composition. The coating composition of the present invention can be applied to asphalt, concrete, iron plate and the like.

<Example 1>
In a first reaction vessel, 50 g of N, N-dimethylformamide as an organic solvent, 17.5 g of diphenylmethane 4,4′-diisocyanate (MDI) and 10 g of organobentonite were placed and heated to 40 ° C. The organic bentonite is bentonite treated with dimethyldioctadecylammonium (Rheox, BENTONE 34).
In a separate container, 50 g of N, N-dimethylformamide and 18.06 g of octylamine were placed, heated to 70 ° C., added to the first reaction container, and stirred.
Stirring was continued at about 70 ° C. for about 30 minutes, and after sufficient reaction, the mixture was cooled to room temperature. After separation by centrifugation, washing with pure water was performed to remove N, N-dimethylformamide. The washed product was dried in a constant temperature bath at 100 ° C. to obtain the desired composite. The urea clay composite of Example 1 is referred to as a C8 urea clay composite.

<Example 2>
A urea clay composite was prepared in the same manner as in Example 1 except that 25.9 g of dodecylamine was used instead of octylamine. The urea clay composite of Example 2 is referred to as C12 urea clay composite.

<Example 3>
A urea clay composite was prepared in the same manner as in Example 1 except that 37.66 g of octadecylamine was used instead of octylamine. The urea clay composite of Example 3 is referred to as C18 urea clay composite.
The composites of Examples 1 to 3 thus obtained were subjected to the following test.
<Reference Example 1>
For comparison, 17.5 g of MDI and 50 g of N, N-dimethylformamide as an organic solvent were placed in a first reaction vessel and heated to 40 ° C. In a separate container, 18.06 g of octylamine and 50 g of N, N-dimethylformamide as an organic solvent were placed, heated to 70 ° C., added to the first reaction container, and stirred. Stirring was continued at about 70 ° C. for about 30 minutes, and after sufficient reaction, the mixture was cooled to room temperature. After separation by centrifugation, washing with pure water was performed to remove N, N-dimethylformamide. The urea compound was prepared by drying the washed product in a 100 ° C. constant temperature bath. The urea compound of Reference Example 1 is referred to as C8 urea.
<Reference Example 2>
A urea compound was prepared in the same manner as in Reference Example 1 except that 25.90 g of dodecylamine was used instead of octylamine. The urea compound of Reference Example 2 is referred to as C12 urea.
<Reference Example 3>
A urea compound was prepared in the same manner as in Reference Example 1 except that 37.66 g of octadecylamine was used instead of octylamine. The urea compound of Reference Example 3 is referred to as C18 urea.

(1) Observation with scanning electron microscope The urea clay composites of Examples 1 to 3 were observed with a scanning electron microscope (SEM). The results are shown in FIGS. For comparison, organic bentonite was also observed. The results are shown in FIG. Organic bentonite exists as a mass (Fig. 4 (a)), and on its surface, a plurality of layers are stacked, and each layer exists along the surface, but most of the layers are turned up. It does not exist (FIGS. 4B and 4C). In contrast, the urea clay composite of the present invention has a smaller lump size than organic bentonite (FIGS. 1 (a), 2 (a) and 3 (a)), and the layers are turned like scales. 1 (b) (c), FIG. 2 (b) (c), FIG. 3 (b) (c)). Further, it can be observed that the urea compound on the line is present on the surface of the layer (FIG. 2C).
From these facts, it is understood that the urea compound is present on the surface of the organic bentonite and in the interlayer. Further, when the urea compound enters the interlayer, the organic bentonite is turned up, and the surface is easily peeled off.

(2) X-ray powder diffraction test The X-ray powder diffraction test of the urea clay composites of Examples 1 to 3 was performed. For comparison, X-ray powder diffraction tests of organic bentonite and urea compounds of Reference Examples 1 to 3 were also conducted. The results are shown in FIGS. As is clear when comparing the chart of organic bentonite (FIG. 5) and the urea compounds of Reference Examples 1 to 3 (FIGS. 6 to 8), the diffraction lines of the organic bentonite and the urea compound do not overlap, and the urea compound is partially Only diffractive lines are allowed. In the urea clay composites of Examples 1 to 3 (FIGS. 9 to 11), diffraction lines attributable to organic bentonite were not observed, but diffraction lines that did not exist in the X-ray chart of organic bentonite appeared.
From these facts, it can be said that the urea clay composite of the present invention has a crystal structure different from organic bentonite and C8-, C12-, C18-urea compounds.

(3) TE-77 friction test (according to ASTM D5707)
The friction coefficients of the urea clay composites of Examples 1 to 3, the urea compounds of Reference Examples 1 to 3, and the organic bentonite were measured.
Test conditions, temperature: room temperature, sliding speed 16mm / s, surface pressure 1.75GPa, test time 600s
Determination When the coefficient of friction is 0.25 or more, the results of the cancellation are shown in FIGS.
From these facts, the urea compound does not have a stable coefficient of friction, and even if it is stable, it is around 0.25. Urea clay composite has a lower friction coefficient than organic bentonite and has a stable friction coefficient at 0.20 or less, so it can be said that it has different friction characteristics from organic bentonite and C8-, C12-, C18-urea compounds.

Claims (13)

  A urea clay composite containing a urea compound between layers of a layered silicate compound. The urea clay composite according to claim 1, wherein the urea compound is represented by the following formula (1).

R1-NHCONH-R2-NHCONH-R3 (1)

(In the formula, R1 and R3 may be the same or different from each other, and each represents a hydrocarbon group having 4 to 22 carbon atoms, such as an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group. R2 represents a hydrocarbon group having 6 to 36 carbon atoms.) The urea clay composite according to claim 1 or 2 obtained by reacting by any one of the following methods (I) or (II):
(I) a system comprising a layered silicate compound and an isocyanate and an organic amine;
(II) a system comprising a layered silicate compound and an organic amine, and a system comprising an isocyanate;
(However, the isocyanate is represented by the formula OCN-R2-NCO, organic amine represented by the formula R1-NH ₂ or R3-NH ₂ (wherein, R1, R2, and R3 are as defined in claim 2 is there.)).   The layered silicate compound is at least one member selected from the group consisting of montmorillonite, bentonite, organic bentonite, hectorite, chlorite, beidellite, vermiculite, saponite, mica, nontronite, bolconscoite, magatite, and kenyaite. The urea clay composite of any one of 1-3.   The urea clay composite according to any one of claims 2 to 4, wherein the isocyanate is a diisocyanate selected from the group consisting of tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, and dimer diisocyanate.   Organic amines are aliphatic amines octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, nonyldecylamine, eico The urea clay according to any one of claims 2 to 5, which is at least one selected from the group consisting of silamine, docosylamine, aromatic amine paratoluidine, aniline, naphthylamine, and alicyclic amine cyclohexylamine. Composite.   The urea clay composite according to any one of claims 1 to 6, comprising 0.1 to 80 parts by mass of the layered silicate compound with respect to 100 parts by mass of the urea clay composite.   The lubricant composition containing the urea clay composite of any one of Claims 1-7.   The grease composition containing the urea clay composite of any one of Claims 1-7.   A metalworking fluid composition comprising the urea clay composite according to any one of claims 1 to 7.   The plastic composition containing the urea clay composite of any one of Claims 1-7.   The coating composition containing the urea clay composite of any one of Claims 1-7. A method for producing a urea clay composite comprising the following steps (I) or (II):
(I) a step of reacting a system containing a layered silicate compound and an isocyanate with a system containing an organic amine;
(II) A step of reacting a system containing a layered silicate compound and an organic amine with a system containing an isocyanate.