JP3131677B2 - Inorganic substance coated with silane coupling agent and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silane coupling agent-coated inorganic substance and a method for producing the same. The inorganic substance coated with a silane coupling agent of the present invention is suitable as a filler or reinforcing material for various materials such as rubber, plastics, sealants, and paints.

[0002]

2. Description of the Related Art As a filler for various materials such as polymers,
Various inorganic powders are used. BACKGROUND ART In order to increase the bonding strength between an inorganic powder for polymer filling and a polymer, surface coating of the inorganic powder with a silane coupling agent has been performed. However, for inorganic powders such as silica, kaolin clay, mica, talc, and aluminum hydroxide, the effect of coating treatment with a silane coupling agent is observed, but carbonates of alkaline earth metals such as calcium, magnesium, barium, etc. Inorganic powders such as salts, sulfites and phosphates have almost no coating effect.

[0003] Therefore, as a method of exhibiting the effect of the silane coupling agent on these alkaline earth metal salt powders, the surface of the powder particles is coated in advance with silica hydrosol and then further treated with a silane coupling agent. Double coating method of coating with a ring agent (JP-B-52-3906)
No. 1) has been proposed. However, this method requires not only double coating, but also the effect of the silane-based coupling agent is exhibited only by coating the silica hydrosol in the primary treatment. For coating, it is necessary to perform a surface coating treatment in the presence of a large amount of water in a wet or semi-dry state. For this reason, this double-coating method has a disadvantage that the operation is complicated when it is carried out industrially.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a silane coupling agent-coated inorganic substance which exhibits a coating effect with a silane coupling agent regardless of the type of the inorganic substance. An object of the present invention is to provide a method for producing a silane coupling agent-coated inorganic substance for easily performing a silane coupling agent treatment on the inorganic substance.

[0005]

Means for Solving the Problems The present inventors have proposed that various inorganic substances can be surface-treated with a silane-based coupling agent by a dry method or a wet method, and that the silane-based coupling agent can be treated only once. As a result of intensive studies with the aim of expressing the treatment effect of the system-based coupling agent, the silane obtained by subjecting the coating material in which the silane-based coupling agent and polymethoxysiloxane coexist to the inorganic material to a surface coating treatment is obtained. The present inventors have found that a coupling agent-coated inorganic substance efficiently gives a reinforcing property to a compound composition such as a polymer, and have completed the present invention.

The present invention resides in a silane coupling agent-coated inorganic substance whose surface is coated with a coating agent in which a silane coupling agent and polymethoxysiloxane coexist. The present invention resides in a method for producing a silane coupling agent-coated inorganic substance, which comprises coating the surface of an inorganic substance with a coating agent in which a silane coupling agent and polymethoxysiloxane coexist. In the present invention, the silane-based coupling agent and the polymethoxysiloxane are separately and simultaneously added to the inorganic substance, and the resulting mixture is stirred by using a stirrer, whereby the surface of the inorganic substance is subjected to the silane-based coupling. A method for producing an inorganic substance coated with a silane coupling agent, characterized by coating with a coating agent in which an agent and polymethoxysiloxane coexist.

[0007] Silane coupling agent-coated inorganic material will further illustrate the present invention. In the inorganic material coated with the silane coupling agent of the present invention, the coating material covering the surface of the inorganic material may be one or two selected from both groups of silane coupling agent: A and polymethoxysiloxane: B. More than one species is included in the coexistence state of A and B. As the silane coupling agent, at least one selected from the group consisting of a methyl acrylate group, an epoxy group, an amino group, a vinyl group, a ureido group, a cyclopropyl group, a mercapto group and a bis (triethoxysilylpropyl) group. A silane coupling agent having an organic functional group can be used.

As such a silane coupling agent, γ-methacryloxypropyltrimethoxysilane,
β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-
β- (aminoethyl) -γ-aminopropyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (2-methoxyethoxy) silane, γ-ureidopropyltriethoxysilane, γ-
Chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, bis (3triethoxysilylpropyl) tetrasulfide and the like can be mentioned.

The polymethoxysiloxane has a general formula
(1): CH_ThreeO- [Si (OCH _Three)_Two-O]_nCH
_Three[However, n is an integer of 2 to 8 in the general formula (1)]
In particular, a number average molecular weight of 10
Those having a value of 00 or less are preferable. Specific polymethoxysilo
Xan is MKC silicate MS5 manufactured by Mitsubishi Chemical Corporation.
1 (trade name), MKC silicate MS56 (trade name), etc.
Can be mentioned.

[0010] The inorganic substance serving as a base for coating the above-mentioned coating agent is not particularly limited. The present invention provides the effect of the coating of the silane coupling agent only in the above-mentioned coating treatment with the silane coupling agent alone, for example, the effect of improving the reinforcing property by coating when the coated inorganic substance is blended with the polymer composition. This is suitable when using an alkaline earth metal salt from which is not obtained. Alkaline earth metal salts include calcium, magnesium, barium and other alkaline earth metal carbonates,
Inorganic substances such as sulfates, sulfites, and phosphates are exemplified. The shape of the inorganic substance used in the present invention is not particularly limited. The present invention is generally suitable for the case where powder or granular material is used as an inorganic substance.

The coating amount of the coating agent is not particularly limited and can be appropriately selected according to the intended use of the inorganic material coated with the silane coupling agent. It is preferable that the amount be up to 5.0 parts by weight. The coexistence ratio of the silane coupling agent and the polymethoxysiloxane in the coating agent is 5:95 to 95: 5, preferably 20:80 to 80:20, more preferably 30: 7 by weight ratio.
It is good to be in the range of 0 to 70:30.

Production of inorganic material coated with silane coupling agent
Method The method for producing a silane coupling agent-coated inorganic substance of the present invention comprises coating the surface of the inorganic substance with a coating agent in which a silane coupling agent and polymethoxysiloxane are present together, and the treatment method is not particularly limited. Is not
A known method for coating a silane coupling agent can be applied. Specifically, for inorganic substances,
A coating agent, that is, a silane-based coupling agent and polymethoxysiloxane are added, and the obtained mixture is stirred using a stirrer, so that the surface of the inorganic substance is mixed with the silane-based coupling agent and polymethoxysiloxane. Can be coated with a coating agent which is in a coexisting state.

The inorganic material coated with a silane coupling agent of the present invention is mainly produced by a dry method. As a processing machine, a wet or semi-dry processing machine such as a Henschel mixer, a super mixer, a ribbon blender, a kneader, a Nauter mixer or the like is used. By using a stirrer such as a disperser stirrer, surface coating treatment on an inorganic substance can be performed.

A feature of the present invention resides in a method of adding a coating agent (a silane coupling agent and a polymethoxysiloxane) at the time of this coating. The effect is exhibited when the silane coupling agent and the polymethoxysiloxane of the coating agent are simultaneously added and coated in a coexisting state with the inorganic substance. Specifically, (1) a silane coupling agent: A
And a polymethoxysiloxane: B are mixed to form a coating agent in which both components coexist, and then coated on the surface of an inorganic substance. (2) Silane-based coupling agent: A and polymethoxysiloxane: B Is separately added to the inorganic substance to coat the surface of the inorganic substance, whereby the surface of the inorganic substance can be surface-coated with a coating agent in which A and B coexist.

In the case of the method (1), a silane coupling agent: A and a polymethoxysiloxane: B are preliminarily mixed to prepare an A / B addition coexisting coating agent in which A is added to B. Alternatively, A and B may be mixed immediately before the coating treatment. For example, MKC silicate MSEP2 (trade name) (γ-glycidoxypropyltrimethoxysilane added silicate), MKC silicate AM1 (trade name) manufactured by Mitsubishi Chemical Corporation as an A / B addition coexisting coating agent
(Γ-aminopropyltriethoxysilane-added silicate) and the like. In the case of the method (2), it is preferable to simultaneously add the silane coupling agent and the polymethoxysiloxane to the inorganic substance from the viewpoint that the silane coupling agent and the polymethoxysiloxane coexist in a favorable state.

The amounts of the silane-based coupling agent and the polymethoxysiloxane are not particularly limited, but the total amount of both is 0.1 to 100 parts by weight of the inorganic substance.
It is preferable that the amount be up to 5.0 parts by weight. The ratio of the silane coupling agent to the polymethoxysiloxane used is preferably in the range of 5:95 to 95: 5 by weight. The temperature at the time of the coating treatment can be arbitrarily set depending on the type of the coating agent obtained from the silane coupling agent and the polymethoxysiloxane.

[0017]

The present invention will be described below in more detail with reference to examples and application examples.

[Production of Inorganic Substance Coated with Silane Coupling Agent] Example 1 A specific surface area of 12,000 cm ² measured by an air permeation method was placed in a Henschel mixer vessel having a jacket inner volume of 20 L.
/ G of heavy calcium carbonate powder, and the jacket temperature and the powder temperature were both set to room temperature.
While stirring the powder at 000 rpm, 0.5 part of coating agent γ-glycidoxypropyltrimethoxysilane (trade name: A-187, manufactured by Nippon Unicar Co.) was added per 100 parts by weight of heavy calcium carbonate, and Methoxysiloxane (trade name: MKC silicate MS51, manufactured by Mitsubishi Chemical Corporation)
And 0 parts before mixing, and added to the powder.
Stirring and mixing were continued for a minute to obtain an epoxysilane-coated heavy calcium carbonate powder of the present invention.

Example 2 The same amounts of γ-glycidoxypropyltrimethoxysilane and polymethoxysiloxane as in the coating of Example 1 were separately and simultaneously added to the heavy calcium carbonate powder. The same operation as in Example 1 was performed to obtain an epoxysilane-coated heavy calcium carbonate powder of the present invention.

Example 3 As a coating agent, one obtained by previously adding and condensing γ-glycidoxypropyltrimethoxysilane and polymethoxysiloxane (trade name: MKC silicate MSEP2, manufactured by Mitsubishi Chemical Corporation) was used. The same operation as in Example 1 was performed, except that 1.5 parts by weight was added per 100 parts by weight of calcium carbonate, to obtain an epoxysilane-coated heavy calcium carbonate powder of the present invention.

Example 4 A 10% aqueous solution of calcium hydroxide (milk of lime) adjusted to a concentration of 15% and a temperature of 25 ° C. was blown with carbon dioxide gas having a concentration of 30% at a rate of 5 L / min per kg of calcium hydroxide. A suspension was obtained. The obtained compounded calcium carbonate (BET specific surface area of 5.0 m ² when finished into powder)
/ G) While stirring the suspension using a disper stirrer, 1.5 parts by weight of calcium carbonate (solid content) per 100 parts by weight of the same coating agent as in Example 3 (trade name:
MKC silicate (MSEP2) is treated with ethyl alcohol 2
Diluted by a factor of 1 before adding. Next, this calcium carbonate was dewatered by press, dried and pulverized to obtain an epoxysilane-coated synthetic calcium carbonate powder of the present invention.

Example 5 γ-glycidoxypropyltrimethoxysilane, one of the components of the coating material of Example 1, was converted to γ-aminopropyltriethoxysilane (trade name: A-1100, manufactured by Nippon Unicar). Except having changed, the same operation as in Example 1 was performed.
An aminosilane-coated heavy calcium carbonate powder of the present invention was obtained.

Example 6 γ-glycidoxypropyltrimethoxysilane, one of the components of the coating composition of Example 1, was replaced with bis (3 triethoxysilylpropyl) tetrasulfide (trade name: Si6
9, manufactured by Degussa Deutschland GmbH), and the same operation as in Example 1 was carried out to obtain a tetrasulfide silane-coated heavy calcium carbonate powder of the present invention.

Example 7 The heavy calcium carbonate of Example 1 was applied to barite powder (main component: barium sulfate) having a specific surface area of 8000 cm ² / g by air permeation method, and polymethoxysiloxane was applied to MKC silicate MS51. MKC silicate MS
Except having changed to 56, the same operation as Example 1 was performed to obtain the epoxysilane-coated barite powder of the present invention.

[0025] Example 8 a heavy calcium carbonate specific surface area by air permeation method of Example 3 12000 ² / g from 18000cm ² / g
The same operation as in Example 3 was carried out except that the above was changed to, to obtain an epoxysilane-coated heavy calcium carbonate powder of the present invention.

Example 9 MKC silicate MSEP2 which is a coating agent of Example 8
(Trade name) was changed to bis (3 triethoxysilylpropyl) tetrasulfide (trade name: Si69, manufactured by Degussa Deutschland) and polymethoxysiloxane (trade name: MKC silicate MS51, manufactured by Mitsubishi Chemical Corporation), and heavy calcium carbonate was used. 0.5 parts by weight and 100 parts by weight per 100 parts by weight.
The same operation as in Example 1 was performed, except that 0 parts by weight was added, to obtain a tetrasulfide silane-coated heavy calcium carbonate powder of the present invention.

Example 10 Bis (3 triethoxysilylpropyl) tetrasulfide of Example 9 was changed to γ-aminopropyltriethoxysilane, and the amount of polymethoxysiloxane (trade name: MKC silicate MS51, manufactured by Mitsubishi Chemical Corporation) was added. Was increased from 1.0 part to 2.5 parts to obtain the aminosilane-coated heavy calcium carbonate powder of the present invention.

Comparative Example 1 The same operation as in Example 1 was carried out except that polymethoxysilicate, one of the components of the coating agent of Example 1, was not added. I got a body.

Comparative Example 2 MKC silicate MSEP2 which is a coating agent of Example 4 was changed to γ-glycidoxypropyltrimethoxysilane.
The same operation as in Example 4 was performed except that polymethoxysilicate, which is another component of the coating agent, was not added, to obtain a synthetic calcium carbonate coated with epoxysilane alone.

Comparative Example 3 The same operation as in Example 7 was carried out except that polymethoxysilicate, one of the components of the coating agent of Example 7, was not added, to obtain a barite powder coated with epoxysilane alone. Was.

Comparative Example 4 The procedure of Example 1 was repeated except that γ-glycidoxypropyltrimethoxysilane (trade name: A-187, manufactured by Nippon Unicar), one of the components of the coating agent of Example 1, was not added. The same operation as in Example 1 was performed to obtain heavy calcium carbonate powder coated with polymethoxysilicate alone.

Comparative Example 5 Bis (3 triethoxysilylpropyl) tetrasulfide (trade name: S) which is one of the components of the coating agent of Example 9
i69, Degussa, Germany)
The same operation as in Example 9 was performed to obtain heavy calcium carbonate coated with polymethoxysilicate alone.

Comparative Example 6 The same operation as in Example 9 was carried out except that polymethoxysilane, one of the components of the coating agent of Example 9, was not added. A powder was obtained.

Comparative Example 7 The same operation as in Example 10 was carried out except that polymethoxysilane, one of the components of the coating agent in Example 10, was not added, and heavy calcium carbonate coated with tetrasulfide silane alone was used. A powder was obtained.

Table 1 shows an outline of the samples (inorganic substances coated with a silane coupling agent) obtained in Examples 1 to 10 and Comparative Examples 1 to 7 and Reference Samples 1 and 2.

[0036]

[Table 1]

In Table 1, "A" indicates the specific surface area (cm ² / g) by the air permeation method, and "B" indicates the BET specific surface area (m ² / g). In Table 1, "Coating agent A" indicates a silane coupling agent, "Coating agents A and B" indicate silane coupling agent-added polymethylsiloxane, and "Coating agent B" indicates polymethylsiloxane.

"No. 1" of the coating agent in Table 1 is γ-glycidoxypropyltrimethoxysilane (trade name: A-1)
87, manufactured by Nippon Unicar Co., Ltd., “No. 2” is a polymethoxysiloxane with γ-glycidoxypropyltrimethoxysilane (trade name: MKC silicate MSEP2, manufactured by Mitsubishi Chemical Corporation), and “No. 3” is γ. No. 4 is bis (3-triethoxysilylpropyl) tetrasulfide (trade name: Si6).
9, Degussa Deutschland, Germany) and "No. 5" is polytrimethoxysiloxane (trade name: MKC silicate MS5)
1, Mitsubishi Chemical Corporation), and "No. 6" indicates polytrimethoxysiloxane (trade name: MKC silicate MS56, manufactured by Mitsubishi Chemical Corporation).

In Table 1, the number in parentheses for the coating agent indicates the amount (parts by weight) of the coating agent per 100 parts by weight of the inorganic substance. In Table 1, "1" indicates the method of adding the coating agent A and the coating agent B immediately before addition to the inorganic substance, and "2" indicates that the coating agent A and the coating agent B were separately added. At the same time, the method of simultaneously adding the coating material A to the inorganic material, that is, the method of adding the coating material A to the coating material B in advance, that is, the method of adding the coating materials A and B to the inorganic material is shown.

[Characteristic Evaluation Test] In order to confirm the coating effect of the inorganic substance coated with the silane coupling agent of the present invention, physical properties such as modulus and tensile strength were examined by blending and applying to rubber. The composition is shown in Tables 2, 4 and 6. Also,
Tables 3 and 5 show the measurement results of the physical properties of each sample corresponding to them.
And Table 7 below. Any of the silane coupling agent-coated inorganic materials of the present invention has a higher modulus than the same parent silane coupling agent-coated inorganic material or polymethoxysiloxane-coated inorganic material which is not according to the present invention, or the same parent untreated inorganic material. Or the tensile strength improves considerably,
A remarkable coating effect was observed.

Application Example 1 (comprising epichlorohydrin rubber)

[0042]

Table 2 Ingredients Compounding amount Epichromer C 100 (PHR) [Epichlorohydrin / ethylene oxide molar copolymer rubber (manufactured by Daiso Corporation)] Zinc stearate 1 Zinc white 5 Antioxidant NBC [Ni-dibutyldithiocarbamate] 1 Acceleration Agent # 22 [ethylenethiourea] 50 samples 50

[0043]

Table 3 Sample Vulcanization (155 ° C.) Time (min) TB EB Hs Example 1 45 40 275 55 Example 2 45 38 270 55 Example 3 45 41 260 55 Example 4 45 49 255 61 Example 5 45 36 260 54 Example 7 50 37 270 55 Comparative Example 1 45 23 300 55 Comparative Example 2 45 30 245 62 Comparative Example 3 50 21 310 55 Reference Example 1 50 22 320 54

Application Example 2 (compounding isoprene rubber)

[0045]

Table 4 Components Compounding amount IR-10 [polyisoprene rubber (manufactured by Kuraray Co., Ltd.)] 100 (PHR) zinc white 5 stearic acid 2 accelerator DM [dibenzothiazole disulfide] 1 accelerator D [diphenylguanidine] 0 .3 sulfur 2 samples 75

[0046]

Table 5 Sample Vulcanization (141 ° C) Time (min) M300 M500 TB EB Hs Example 1 20 33 84 204 665 52 Example 2 20 32 80 205 670 52 Example 3 20 35 86 86 208 660 53 Example 4 15 42 114 213 640 55 Example 5 15 64 129 203 620 53 Example 6 15 36 88 206 670 51 Example 7 20 31 78 203 660 52 Example 10 15 67 165 208 620 50 Comparative example 1 20 23 58 58 203 705 52 Comparative Example 2 15 27 76 202 645 53 Comparative Example 3 20 22 56 203 700 52 Comparative Example 4 20 24 60 210 710 51 Comparative Example 7 20 26 79 218 670 52 Reference Example 1 20 23 58 206 206 705 51 Reference Example 2 20 24 74 2 30 710 52 .

Application Example 3 (NR-SBR blended)

[0048]

Table 6 Components Compounding amount SMR CV-60 [Natural rubber] 50 (PHR) Tuffden # 2003 [Styrene-butadiene copolymer rubber] 50 Zinc white 5 Stearic acid 1.2 Accelerator DM [Dibenzothiazole disulfide] 1 Acceleration Agent TT [tetramethylthiuram disulfide] 0.3 microcrystalline wax [paraffin wax] 2 Diana Process NM280 [mineral oil] 8 sulfur 2.2 HAF (CB, Asahi # 70) 20 samples 188

[0049]

Table 7 Sample Vulcanization (141 ° C.) Time (min) M300 TB EB Hs Example 8 7 75 88 360 77 Example 9 7 79 86 400 75 Comparative Example 5 7 49 71 430 73 Comparative Example 6 7 50 82 450 72 Reference Example 2 5 51 83 460 74

[0050]

The silane coupling agent-coated inorganic substance of the present invention is remarkably reinforced with respect to modulus, tensile strength, bending strength, coating strength, etc. by being added to rubber, plastic, sealant, paint, etc. Express the effect. According to the production method of the present invention, a specific inorganic substance needs to be double-coated as in the conventional method using a coexisting coating agent of a silane coupling agent and polymethoxysiloxane as a coating agent for the inorganic substance. In addition, since the surface coating can be performed even by a single coating method of the dry method, the operation is simple.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-68041 (JP, A) JP-A-63-130625 (JP, A) JP-A-59-45906 (JP, A) 39061 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08K 9/06 C09C 3/12

Claims (10)

(57) [Claims] An inorganic substance coated with a silane coupling agent, wherein the surface is coated with a coating agent in which a silane coupling agent and polymethoxysiloxane coexist. 2. The silane coupling agent is selected from the group consisting of a methyl acrylate group, an epoxy group, an amino group, a vinyl group, a ureido group, a cyclopropyl group, a mercapto group and a bis (triethoxysilylpropyl) group. A silane-based coupling agent having at least one organic functional group, and polymethoxysiloxane having a general formula (1): CH ₃ O— [Si (OCH ₃ ) ₂ —O] _n CH
_3. The silane coupling agent-coated inorganic substance according to claim 1, which is a polymethoxysiloxane represented by [where n is an integer of 2 to 8 in the general formula (1)]. 3. The coating amount of the coating agent is 0.1 to 5.0 parts by weight based on 100 parts by weight of the inorganic substance, and the coexistence ratio of the silane coupling agent and the polymethoxysiloxane in the coating agent. Is a weight ratio of 5:95 to 95: 5, the inorganic material coated with a silane coupling agent according to claim 1 or 2. 4. The silane coupling agent-coated inorganic substance according to claim 1, wherein the inorganic substance is a powder of an alkaline earth metal salt. 5. A method for producing an inorganic substance coated with a silane coupling agent, comprising coating the surface of the inorganic substance with a coating agent in which a silane coupling agent and polymethoxysiloxane coexist. 6. A silane-based coupling agent and polymethoxysiloxane are mixed to form a coating agent in which both components are present, and the obtained coating agent is added to an inorganic substance. A method for producing an inorganic material coated with a silane coupling agent, wherein the surface of the inorganic material is coated with a coating agent in which a silane coupling agent and polymethoxysiloxane coexist by stirring the mixture. 7. The method for producing a silane coupling agent-coated inorganic substance according to claim 6, wherein the silane coupling agent and the polymethoxysiloxane are mixed immediately before being added to the inorganic substance to form a coating agent. 8. The coating agent according to claim 6, wherein the silane coupling agent and the polymethoxysiloxane are mixed in advance and the silane coupling agent is added to the polymethoxysiloxane to form a coating agent in which both components coexist. A method for producing an inorganic substance coated with a silane coupling agent. 9. A silane-based coupling agent and polymethoxysiloxane are separately and simultaneously added to an inorganic substance, and the resulting mixture is stirred using a stirrer, whereby the surface of the inorganic substance is mixed with the silane-based coupling agent. A method for producing an inorganic material coated with a silane coupling agent, comprising coating with a coating agent in which a ring agent and polymethoxysiloxane coexist. 10. The total amount of the silane coupling agent and the polymethoxysiloxane used (the amount of the coating agent) is 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the inorganic substance; The method for producing an inorganic material coated with a silane coupling agent according to any one of claims 5 to 9, wherein the weight ratio of the silane coupling agent and the polymethoxysiloxane is 5:95 to 95: 5.