JP2001226383A - Sulfur-containing organosilicon compound, and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new sulfur-containing organosilicon compound useful as a modifier of the processability and rubber properties of an organic rubber composition, and further to provide a method for efficiently producing the compound under a comparatively mild condition. SOLUTION: This sulfur-containing organosilicon compound is represented by the general formula [R1 is a 1-4C alkyl group; R2 is a 1-4C alkyl group; R3 is a 2-15C divalent hydrocarbon group; R4 is a hydrogen atom or a 1-4C alkyl group; (a) is an integer of 1-3; x is an integer of 1-6; m is an integer of >=0; and p is an integer of >=0]. The method for producing the sulfur- containing organosilicon compound is characterized in that an organosilicon compound represented by the general formula R4-CH=CH-CH2-R3-Si(OR1)aR2(3-a) is reacted with sulfur in an amount of 0.5-4 mol sulfur atom based on 1 mol organosilicon compound at a temperature from room temperature to 200 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sulfur-containing organosilicon compound and a method for producing the same, and more particularly to a novel sulfur-containing organosilicon compound useful as a processability or rubber property modifier for an organic rubber composition. And a method for efficiently producing the sulfur-containing organosilicon compound under relatively mild conditions.

[0002]

2. Description of the Related Art A sulfur-containing organosilicon compound is added to an organic rubber composition such as a diene rubber composition to reduce the viscosity, improve the kneading workability, and improve the properties of the molded organic rubber. Since rubber elasticity such as mechanical strength and viscoelastic properties can be improved, it is used as an additive for modifying rubber compositions for tires and rubber rolls.

As such a sulfur-containing organosilicon compound,
Bis- (alkoxysilylethyl) -oligosulfide
(See Japanese Patent Application Laid-Open No. 55-89290) and cyclic sulfide compounds containing a silyl group (see Japanese Patent Application Laid-Open No. 11-80209). Further, as a method for producing a sulfur-containing organosilicon compound, vinylalkoxysilane is used. And one sulfur
A reaction at 00 to 200 ° C. under a pressure of 1 to 25 bar with a sulfide catalyst (see JP-A-55-89290); an organic silicon compound having an alkenyl group having 2 to 4 carbon atoms; A method of reacting a sulfide has been proposed (see JP-A-11-80209).

[0004] However, the sulfur-containing organosilicon compounds proposed in JP-A-55-89290 and JP-A-11-80209 have a problem that the effect as a modifying additive for organic rubber is not sufficient. Also, Japanese Unexamined Patent Publication No.
The method for producing a sulfur-containing organosilicon compound proposed in Japanese Patent No. 89290 has a problem that the reaction must be performed at a high temperature and a high pressure of 1 to 25 bar at 100 to 200 ° C.

[0005]

DISCLOSURE OF THE INVENTION The present inventors have intensively studied the above-mentioned problems, and as a result, have reached the present invention. That is, an object of the present invention is to provide a novel sulfur-containing organosilicon compound that is useful as a processability or rubber property modifier of an organic rubber composition, and furthermore, to relatively disperse this sulfur-containing organosilicon compound. An object of the present invention is to provide a method for efficiently producing under mild conditions.

[0006]

The sulfur-containing organosilicon compound of the present invention has the general formula:

Embedded image (Wherein, R ¹ is an alkyl group having 1 to 4 carbon atoms, R ² is an alkyl group having 1 to 4 carbon atoms, and R ³ is an alkyl group having 2 to 1 carbon atoms.
5 is a divalent hydrocarbon group, R ⁴ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, a is an integer of 1 to 3, x is an integer of 1 to 6, and m is It is an integer of 0 or more, and p is an integer of 0 or more. ).

Further, the sulfur-containing organosilicon compound of the present invention comprises
General formula:

Embedded image (Wherein, R ¹ is an alkyl group having 1 to 4 carbon atoms, R ² is an alkyl group having 1 to 4 carbon atoms, and R ³ is an alkyl group having 2 to 1 carbon atoms.
5 is a divalent hydrocarbon group, R ⁴ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, a is an integer of 1 to 3, x is an integer of 1 to 6, and n is It is an integer of 1 or more, and p is an integer of 0 or more. ).

The method for producing a sulfur-containing organosilicon compound of the present invention is represented by the general formula: R ⁴ —CH ＝ CH—CH ₂ —R ³ —Si (OR ¹ ) _a R ² _(3-a) , R ¹ is an alkyl group having 1 to 4 carbon atoms, R ² is an alkyl group having 1 to 4 carbon atoms, and R ³ is an alkyl group having 2 to 1 carbon atoms.
5 is a divalent hydrocarbon group, R ⁴ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and a is an integer of 1 to 3. ) Is reacted at room temperature to 200 ° C. with 0.5 to 4 mol of sulfur atoms per 1 mol of the organosilicon compound.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION First, the sulfur-containing organosilicon compound of the present invention will be described in detail. The sulfur-containing organosilicon compound of the present invention has a general formula:

Embedded image Or a general formula:

Embedded image Indicated by R ¹ in the above formula is an alkyl group having 1 to 4 carbon atoms, and is exemplified by a methyl group, an ethyl group, a propyl group, and a butyl group, and is preferably a methyl group or an ethyl group. R ² in the above formula is an alkyl group having 1 to 4 carbon atoms, and examples thereof include the same alkyl groups as those described above for R ¹ , preferably a methyl group or an ethyl group. R ³ in the above formula is a divalent hydrocarbon group having 2 to 15 carbon atoms, and an alkylene group such as an ethylene group, a propylene group, and a butylene group;
Examples thereof include an alkylene arylene group such as a methylene phenylene group and an ethylene phenylene group, preferably an alkylene group, and particularly preferably an ethylene group or a propylene group. R ⁴ in the above formula is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group of R ⁴ include the same alkyl groups as those described above for R ¹ .
In particular, R ⁴ is preferably a hydrogen atom. A in the above formula is an integer of 1 to 3, preferably 3. Further, x in the above formula is an integer of 1 to 6. Further, m in the above formula is an integer of 0 or more. Also, p in the above equation is 0
Is an integer greater than or equal to. Further, n in the above formula is an integer of 1 or more.

As such a sulfur-containing organosilicon compound of the present invention, the following compounds are exemplified. However, x in the formula is an integer of 1 to 6, m is an integer of 0 or more,
n is an integer of 1 or more, and p is an integer of 0 or more.

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Since the sulfur-containing organosilicon compound of the present invention has a silicon atom-bonded alkoxy group, an alkenyl group and a sulfide structure or a polysulfide structure, it can be prepared from an organic rubber, an inorganic filler, carbon black, and a vulcanization accelerator. By adding the organic rubber composition to the resulting organic rubber composition, the processability of the organic rubber composition can be improved, and the rubber properties, particularly, the mechanical strength of the organic rubber obtained by curing can be improved. The addition amount of the sulfur-containing organosilicon compound of the present invention is 0.1 to 2 parts by weight based on 100 parts by weight of the inorganic filler.
It is preferably 0 parts by weight, more preferably 1 to 20 parts by weight, and particularly preferably 1 to 15 parts by weight. Thus, the sulfur-containing organosilicon compound of the present invention is useful as a processability or rubber property modifier for organic rubber compositions, or as a surface modifier for inorganic fillers for organic rubber.

[0012] In the organic rubber composition to which the sulfur-containing organosilicon compound of the present invention can be blended, the main component of the organic rubber is styrene-butadiene copolymer rubber, polybutadiene rubber, cis-polybutadiene copolymer. Rubber, styrene-isoprene copolymer rubber, styrene-isoprene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, isoprene rubber, natural rubber, butyl rubber, halogenated butyl rubber, 2-
Illustrative are chlorobutadiene rubbers, terpolymers from ethylene, propylene and conjugated dienes, carboxyl rubbers, epoxide rubbers, trans-polypentenamers, ethylene-vinyl acetate copolymers, ethylene-propylene copolymers, and mixtures thereof.

Examples of the inorganic filler include silica fillers such as fumed silica, wet silica, and quartz powder; aluminum oxide, titanium oxide, zinc oxide, calcium carbonate, barium carbonate, magnesium carbonate, aluminum hydroxide, and silicate. Examples thereof include aluminum, magnesium silicate, and diatomaceous earth, and a silica-based filler is particularly preferable. The amount of the inorganic filler is 5 to 100 parts by weight of the organic rubber.
It is preferably 200 parts by weight, more preferably 5-1.
It is preferably 50 parts by weight, particularly preferably 10 to 10 parts by weight.
It is preferably 0 parts by weight.

Examples of carbon black include thermal black, acetylene black and furnace black. The compounding amount of the carbon black is preferably 0 to 200 parts by weight, more preferably 0 to 100 parts by weight, particularly preferably 1 to 100 parts by weight, based on 100 parts by weight of the organic rubber. Preferably, there is.

Examples of the vulcanization accelerator include thiazole accelerators including dithiocarbamate accelerators, xanthogenate accelerators, thiuram accelerators, mercapto and sulfinamide accelerators, amine accelerators, aldehyde amine accelerators, and mercapto accelerators. Accelerators, disulfide accelerators, polysulfide accelerators are exemplified. The amount of the vulcanization accelerator is preferably 5 to 10 parts by weight based on 100 parts by weight of the organic rubber.

Further, the above-mentioned organic rubber composition contains a plasticizer for rubber such as paraffin-based hydrocarbon, naphthene-based hydrocarbon and aromatic-based hydrocarbon for improving the moldability and processability of the organic rubber composition. Vulcanizing agents such as zinc white and stearic acid; anti-aging agents such as diphenylamines, trimethyldihydroquinones, and phenylenediamines; various heat-resistant agents; reinforcing additives and the like.

The above organic rubber composition comprises two or three rolls of an organic rubber, an inorganic filler, carbon black, the sulfur-containing organosilicon compound of the present invention, a vulcanization accelerator, and other optional components. It can be prepared by uniformly mixing with a kneading device such as a kneader mixer. After the organic rubber composition thus obtained is cured,
Rubber properties, especially because it becomes a rubber with excellent mechanical strength,
For example, it is suitable for forming rubber tires for automobiles and bicycles.

Next, the method for producing the sulfur-containing organosilicon compound of the present invention will be described in detail. The production method of the present invention comprises reacting an organosilicon compound represented by the general formula: R ⁴ —CH ＝ CH—CH ₂ —R ³ —Si (OR ¹ ) _a R ² _(3-a) with sulfur at room temperature to 200 ° C. It is characterized by reacting.

In the above organosilicon compound, R in the formula
¹Is an alkyl group having 1 to 4 carbon atoms, and is the same group as described above.
Is exemplified. In addition, R in the above equation^TwoIs a group having 1 to 4 carbon atoms.
And the same groups as described above. Also,
R in the above formula^ThreeIs a divalent hydrocarbon group having 2 to 15 carbon atoms.
And the same groups as described above. In addition, R in the above equation^Four
Is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,
R^FourExamples of the alkyl group include the same groups as described above.
You. A in the above formula is an integer of 1 to 3, preferably
Is 3.

As such an organosilicon compound, 5-
Hexenyltrimethoxysilane, 5-hexenylmethyldimethoxysilane, 5-hexenyltriethoxysilane and 5-hexenylmethyldiethoxysilane are exemplified.

The sulfur that can be used in the production method of the present invention is not limited. The sulfur is preferably anhydrous sulfur, and the shape is preferably a powder or flake.

In the production method of the present invention, the sulfur is added in such an amount that the sulfur atom is 0.5 to 4 mol per 1 mol of the above-mentioned organosilicon compound. In order to have a tetrasulfide structure having four sulfur atoms in one molecule, the amount is preferably such that the sulfur atom is 4 moles per 1 mole of the above-mentioned organosilicon compound, and the trisulfide structure In order to have, it is preferable that the amount of sulfur atoms is 3 mol,
Further, in order to have a disulfide structure, the amount is preferably such that the amount of sulfur atoms is 2 mol.

In the production method of the present invention, a known vulcanization accelerator can be used to increase the reactivity of sulfur.
As the vulcanization accelerator, a dithiocarbamate accelerator,
Xanthogenates, thiurams, thiazoles, including mercapto and sulfinamides, amines, amines, aldehydes, mercaptos, disulfides, polysulfides, and polysulfides. After completion, it is preferably a low-boiling vulcanization accelerator which can be distilled off by heating under reduced pressure. As such a vulcanization accelerator, bis (trialkoxysilylalkyl) polysulfide, mercaptoalkyl trialkoxysilane and the like having similar structures are preferable.

In the production method of the present invention, the reaction can be carried out in a solvent. When an alcohol is used as the solvent, the alcohol is preferably an alcohol having a group similar to an alkoxy group bonded to a silicon atom in the organic silicon compound. This means that when alcohols with different groups are used, the alkoxy groups undergo an exchange reaction,
This is because a compound in which two types of alkoxy groups are mixed can be obtained.

In the production method of the present invention, the reaction can be carried out in a dry inert gas atmosphere at a temperature in the range of room temperature to 200 ° C., and particularly in the temperature range of the melting point of sulfur (112.8 ° C.) to 200 ° C. It is preferred to carry out the reaction. This is because if the reaction temperature exceeds the upper limit of the above range, the above-mentioned organosilicon compound may be decomposed, and if the reaction temperature is lower than the lower limit of the above range, the reaction becomes extremely slow.
Next, in the production method of the present invention, the target sulfur-containing organosilicon compound can be obtained by heating under reduced pressure after the completion of the reaction to distill off the unreacted organosilicon compound.

The production method of the present invention produces almost no by-products, no toxic hydrogen sulfide gas, no salts containing sulfur compounds which are difficult to dispose of, and the like. There is a feature that the target sulfur-containing organosilicon compound can be efficiently produced only by heating without the need for a step such as hydrogen.

[0027]

EXAMPLES The sulfur-containing organosilicon compound of the present invention and the method for producing the same will be described in detail with reference to examples.

Example 1 A 500 ml four-necked flask equipped with a reflux condenser and a thermometer under a stream of dry nitrogen was charged with 5
Hexenyltrimethoxysilane 102 g (0.50 mol), sulfur powder 64.0 g (2.00 mol as sulfur atom)
Was added thereto, and the mixture was reacted at 150 ° C. for 3 hours while stirring. Next, after the obtained reaction mixture was cooled to room temperature, unreacted substances were distilled off under the condition of 100 ° C./10 torr. As a result, 154 g of a reddish brown liquid was obtained. The liquid material, infrared spectroscopy (hereinafter, IR), ¹³ C-nuclear magnetic resonance analysis ^{(hereinafter, 1 3 C-NMR),} 29 Si- nuclear magnetic resonance analysis (hereinafter, ²⁹ Si-NMR) was analyzed by The disappearance of the double bond was confirmed, and it was identified as a sulfur-containing organosilicon compound represented by the following average formula.

[0029]

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Example 2 Under a dry nitrogen stream, 5 ml of a 500 ml four-necked flask equipped with a reflux condenser and a thermometer was placed.
246 g (1.00 mol) of hexenyltriethoxysilane, 64.0 g of sulfur powder (2.00 mol as sulfur atom)
Was added thereto and reacted at 150 ° C. for 3 hours while stirring. Next, after the obtained reaction mixture was cooled to room temperature, unreacted substances were distilled off under the conditions of 100 ° C./10 torr, and 303 g of a reddish brown liquid was obtained. When this liquid was analyzed by IR, ¹³ C-NMR and ²⁹ Si-NMR, a decrease in double bonds was confirmed, and it was identified as a sulfur-containing organosilicon compound represented by the following average formula.

[0031]

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Example 3 A 500 ml four-necked flask equipped with a reflux condenser and a thermometer under a stream of dry nitrogen was charged with 5
246 g (1.00 mol) of hexenyltriethoxysilane, 32.0 g of sulfur powder (1.00 mol as sulfur atom)
Was added thereto and reacted at 150 ° C. for 3 hours while stirring. Next, after the obtained reaction mixture was cooled to room temperature, unreacted substances were distilled off under the conditions of 100 ° C./10 torr, to obtain 257 g of a reddish brown liquid. When this liquid was analyzed by IR, ¹³ C-NMR and ²⁹ Si-NMR, a decrease in double bonds was confirmed, and it was identified as a sulfur-containing organosilicon compound represented by the following average formula.

[0033]

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Comparative Example 1 Reflux cooling under a stream of dry nitrogen
Into a 500 ml four-necked flask equipped with a thermometer and thermometer.
162 g (1.00 mol) of lyltrimethoxysilane, sulfur
64.0 g (2.00 mol) of the powder was charged and the mixture was heated at 150 ° C.
The mixture was reacted for 3 hours while stirring. Next, the obtained anti
After cooling the reaction mixture to room temperature, the mixture was cooled to 100 ° C./10 torr.
Unreacted substances were distilled off under the conditions, and a reddish brown liquid
g was obtained. This liquid is IR,¹³ C-NMR, and
And²⁹Analysis by Si-NMR revealed that the double bond
Loss, the sulfur-containing organosilicon represented by the following average formula
The compound was identified.

[0035]

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[Application Example] In a Banbury mixer, 100 parts by weight of styrene-butadiene copolymer rubber, 40 parts by weight of wet silica fine powder, 5 parts by weight of carbon black, and 4 parts by weight of the sulfur-containing organosilicon compound prepared in Example 2 Parts, then 1.5 parts by weight of sulfur powder, 3 parts by weight of zinc white,
2 parts by weight of stearic acid, 2.7 parts by weight of a vulcanization accelerator and 1 part by weight of an antioxidant were added, and these were uniformly mixed to prepare an organic rubber composition (I). Further, in the above organic rubber composition, except that the sulfur-containing organosilicon compound prepared in Example 3 was blended in the same amount as the organic rubber compound prepared in Example 3, instead of the sulfur-containing organic silicon compound prepared in Example 2, Composition (II) was prepared. Further, in the above organic rubber composition, an organic rubber composition was prepared in the same manner as above except that the same amount of bis (triethoxysilylpropyl) tetrasulfide was used instead of the sulfur-containing organosilicon compound prepared in Example 2. (III) was prepared. The properties of these organic rubber compositions and rubbers were measured as follows and are shown in Table 1. [Mooney viscosity of organic rubber composition] JIS K630
Preheating 1 minute, measurement 4 minutes, temperature 130 according to 0-1994
Measured at ° C. The values in Table 1 indicate the values of the organic rubber composition.
It was indicated by an index with the viscosity of (III) being 100. The smaller the index is, the lower the Mooney viscosity is and the more excellent the processability is. [Hardness of Rubber] The hardness was measured with a type A durometer according to JIS K 6253-1997. The values in Table 1 are shown as indices with the hardness of the rubber obtained by curing the organic rubber composition (III) being 100. The larger the index is, the harder it is, and the lower the index is, the softer it is. [Rubber elongation, tensile strength] JIS K6251-1993
The tensile strength and the elongation at break were measured when a tensile test was performed at 25 ° C. using a dumbbell-shaped No. 3 sample in accordance with. The values in Table 1 are shown as an index with the tensile strength and elongation of the rubber obtained by curing the organic rubber composition (III) being 100. The larger the index, the stronger the tensile strength,
Indicates that the elongation is large. [Abrasion resistance of rubber] The abrasion resistance index representing abrasion resistance was determined by using a Lambourn abrasion tester and applying a ground pressure of 5 kg by a method according to the BS (British Standard) standard 903 (part A) D method.
/ Cm ² and a slip ratio of 40%, and were determined by the following equation. Abrasion resistance index = (weight loss of object / weight loss of test specimen) × 100 The values in Table 1 represent the abrasion resistance of the rubber obtained by curing organic rubber composition (III). The abrasion index was represented by an index with 100. The larger the index, the greater the abrasion resistance.

[0037]

[Table 1]

[0038]

Industrial Applicability The sulfur-containing organosilicon compound of the present invention is a novel compound useful as a processability of an organic rubber composition and a rubber physical property modifier. Sulfur-containing organosilicon compounds under relatively mild conditions,
The feature is that it can be manufactured efficiently.

[Brief description of the drawings]

FIG. 1 shows the results of the sulfur-containing organosilicon compound prepared in Example 1.
^{It is a 13} C-nuclear magnetic resonance spectrum chart.

FIG. 2 shows the results of the sulfur-containing organosilicon compound prepared in Example 1.
^{It is a 29} Si-nuclear magnetic resonance spectrum chart.

FIG. 3 shows the results of the sulfur-containing organosilicon compound prepared in Example 2.
^{It is a 13} C-nuclear magnetic resonance spectrum chart.

FIG. 4 shows the results of the sulfur-containing organosilicon compound prepared in Example 2.
^{It is a 29} Si-nuclear magnetic resonance spectrum chart.

FIG. 5 shows the results of the sulfur-containing organosilicon compound prepared in Example 3.
^{It is a 13} C-nuclear magnetic resonance spectrum chart.

FIG. 6 shows the results of the sulfur-containing organosilicon compound prepared in Example 3.
^{It is a 29} Si-nuclear magnetic resonance spectrum chart.

FIG. 7 shows the results of the sulfur-containing organosilicon compound prepared in Comparative Example 1.
^{It is a 13} C-nuclear magnetic resonance spectrum chart.

FIG. 8 shows the results of the sulfur-containing organosilicon compound prepared in Comparative Example 1.
^{It is a 29} Si-nuclear magnetic resonance spectrum chart.

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Claims (3)

[Claims] 1. A compound of the general formula: (Wherein, R ¹ is an alkyl group having 1 to 4 carbon atoms, R ² is an alkyl group having 1 to 4 carbon atoms, and R ³ is an alkyl group having 2 to 1 carbon atoms.
5 is a divalent hydrocarbon group, R ⁴ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, a is an integer of 1 to 3, x is an integer of 1 to 6, and m is It is an integer of 0 or more, and p is an integer of 0 or more. ) A sulfur-containing organosilicon compound represented by the formula: 2. A compound of the general formula: (Wherein, R ¹ is an alkyl group having 1 to 4 carbon atoms, R ² is an alkyl group having 1 to 4 carbon atoms, and R ³ is an alkyl group having 2 to 1 carbon atoms.
5 is a divalent hydrocarbon group, R ⁴ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, a is an integer of 1 to 3, x is an integer of 1 to 6, and n is It is an integer of 1 or more, and p is an integer of 0 or more. ) A sulfur-containing organosilicon compound represented by the formula: 3. A general formula: R ⁴ —CH ＝ CH—CH ₂ —R ³ —Si (OR ¹ ) _a R ² _{(3-a) wherein} R ¹ is an alkyl group having 1 to 4 carbon atoms. R ² is an alkyl group having 1 to 4 carbon atoms, and R ³ is an alkyl group having 2 to 1 carbon atoms.
5 is a divalent hydrocarbon group, R ⁴ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and a is an integer of 1 to 3. Wherein the amount of sulfur to be 0.5 to 4 moles of sulfur atoms per mole of the organic silicon compound is reacted at room temperature to 200 ° C.
A method for producing a sulfur-containing organosilicon compound according to claim 1.