JP3339702B2 - Method for producing silicate oligomer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a silicate oligomer, and more particularly to a method for producing a silicate oligomer having excellent compatibility with various resins.

[0002]

2. Description of the Related Art Hitherto, attempts have been made to use silicate oligomers as physical property improving agents for various resins. However, conventionally known silicate oligomers include polyethylene, polypropylene, polyester, polycarbonate, polyamide, polyvinyl chloride, polyurethane,
Insufficient compatibility with resins such as epoxy and phenol. Therefore, conventionally known silicate oligomers,
It is difficult to uniformly disperse the resin.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a method for producing a silicate oligomer having excellent compatibility with various resins. .

[0004]

That is, the gist of the present invention is a method for producing a silicate oligomer having a functional group and having a molecular weight in terms of polystyrene of 500 to 100,000 as measured by GPC. A tetraalkyl silicate having a number of 1 to 4 or an oligomer obtained by partially hydrolyzing the tetraalkyl silicate and the following chemical formula [Chemical Formula 2]
In co-hydrolyzing a functional alkyl silicate represented by the following formula (same as [Chemical formula 1]), a tetraalkyl silicate having an alkyl group having 1 to 4 carbon atoms or a partially substituted tetraalkyl silicate is added to a hydrolysis product of the functional alkyl silicate. The present invention relates to a method for producing a silicate oligomer, characterized in that an oligomer obtained by hydrolysis is added to carry out polycondensation or hydrolysis.

Embedded image (Wherein, R ¹ is a functional group, R ² is an alkyl group or an alkoxyalkyl group having 1 to 10 carbon atoms, R ³ is a functional group or an alkyl group, m is an integer of 1 to 3, n is an integer of 0 or 1, Represents)

Hereinafter, the present invention will be described in detail. The silicate oligomer in the present invention has a functional group and GP
The molecular weight in terms of polystyrene measured in C is 500 to
100,000.

In the above silicate oligomer, the functional group is not particularly limited as long as it is a reactive functional group, but is selected from the group consisting of an epoxy group, a vinyl group, a mercapto group and an amino group. Certain functional groups are preferred. Particularly preferred functional groups are a group having an epoxy group, a vinyl group and a mercapto group, and the most preferred functional group is
It is a group having an epoxy group or a vinyl group.

The above molecular weight is a polystyrene size-converted molecular weight obtained from GPC measurement under the following conditions and based on the obtained retention time, based on the known relationship between the retention time and the molecular weight of polystyrene. Separation columns: The following three types of polystyrene gel-filled columns (manufactured by Toyo Soda Co., Ltd.) were used by sequentially connecting three columns. "TSK GEL G-1000H""TSK GEL G-2000H""TSK GEL G-4000H" Outflow: tetrahydrofuran (1 ml / min) Outflow temperature: 40 ° C

[0008] Originally, the retention time is the size (dimension) of the molecule.
It has no direct relation to the molecular weight. However, the molecular weight and the molecular size are almost proportional in the same system molecular structure. Therefore, in the present invention, in order to regulate the molecular weight of the silicate oligomer,
The molecular weight in terms of polystyrene size is adopted.

The silicate oligomer according to the present invention comprises:
Basically, a tetraalkyl silicate having 1 to 4 carbon atoms in an alkyl group or an oligomer obtained by partially hydrolyzing the same (hereinafter, both are abbreviated as “tetraalkyl silicate etc.”) and a functional alkyl It can be produced by co-hydrolyzing with silicate.
That is, the tetraalkyl silicate or the like and the functional alkyl silicate are bonded by a dehydration condensation reaction of a silanol group generated by hydrolysis, and as a result, a silicate oligomer having a high molecular weight and having a functional group is generated.

The tetraalkyl silicate has the chemical formula: S
i (OR ⁴ ) ₄ , wherein in the present invention, R ⁴ in the chemical formula has 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group.
The tetraalkyl silicate which is an alkyl group of is preferably used. Specific examples of the above tetraalkyl silicate include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane and the like.

The alkyl silicate oligomer includes:
An oligomer obtained by hydrolyzing the above tetraalkyl silicate at a ratio of 40 to 60% is suitably used. Assuming that all of the alkyl silicate oligomers formed by the hydrolysis are linear compounds, theoretically, the molecular weight should be infinite at 50% of hydrolysis and gelled. Since a cyclic silicate oligomer is also formed, an oligomer having a hydrolysis rate higher than 50% can be stably obtained. Of course, oligomers having a hydrolysis rate lower than 40% can also be used.

It is also possible to use trialkoxysilane in a proportion of 50% by weight or less during the above-mentioned hydrolysis. The above-mentioned hydrolysis rate refers to the hydrolysis rate of an alkoxy group. Therefore, when hydrolysis proceeds theoretically, tetraalkoxysilane (or trialkoxysilane and tetraalkoxysilane) as a raw material and water to be used are used. It can be expressed by an equivalent ratio.

In the present invention, the functional alkyl silicate is represented by the following chemical formula [Chemical formula 3] (same as [Chemical formula 1])
The compound shown by is used.

[0014]

Embedded image

In the above chemical formula, R ¹ is a functional group,
R ² is an alkyl or alkoxyalkyl group having 1 to 10 carbon atoms, R ³ is a functional group or an alkyl group, and m is 1 to 3
And n represents an integer of 0 or 1. R ¹ or R above
The functional group in ³ is preferably a functional group containing at least one group selected from the group consisting of an epoxy group, a vinyl group, a mercapto group, and an amino group. Particularly preferred functional groups are
These are a functional group containing an epoxy group, a functional group containing a vinyl group, and a functional group containing a mercapto group. And as a functional group containing an epoxy group, a glycidoxyalkyl group, an epoxycycloalkyl group, and a functional group containing a vinyl group are a vinyl group itself, a vinylalkyl group, and a mercaptoalkyl group as a functional group containing a mercapto group. It is preferred that the number of carbon atoms in these alkyl groups is in the range of 1 to 5.

The above R ² is an alkyl group or an alkoxyalkyl group having 1 to 5 carbon atoms (in this case, the number of carbon atoms is
OR- means the total number of carbon atoms of both R). And as such an alkyl group or an alkoxyalkyl group, specifically, methyl group, ethyl group, propyl group, isopropyl group, butyl group, pentyl group, methoxymethyl group, methoxyethyl group, methoxypropyl group, methoxyisopropyl group Groups, methoxybutyl, ethoxymethyl, ethoxyethyl, ethoxypropyl, ethoxyisopropyl, propoxymethyl, propoxyethyl and the like.

Specific examples of the functional alkyl silicate include γ-glycidoxypropyltrimethoxysilane, γ
-Glycidoxypropyltriethoxysilane, γ-glycidoxypropyltripropoxysilane, γ-glycidoxypropyltributoxysilane, γ-glycidoxypropyltri (2-methoxy-ethoxy) silane, γ-glycidoxy Propylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldipropoxysilane, γ-glycidoxypropylmethyldibutoxysilane, γ-glycidoxypropylmethidi (2-methoxy -Ethoxy) silane, γ-glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylethyldiethoxysilane, γ-glycidoxypropylethyldipropoxysilane, γ-glycidoxypropylethyldibutoxysilane, γ- Glycidoxypropylethyl Di (2-methoxy - ethoxy) silane, beta (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, beta (3, 4-epoxycyclohexyl) ethyl triethoxysilane, and the like.

Specific examples of other functional alkyl silicates include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrimepropoxysilane, vinyltributoxysilane, vinylmethyldimethoxysilane,
Vinylmethyldiethoxysilane, vinylmethyldipropoxysilane, vinylmethyldibutoxysilane, vinyltri (2-methoxy-ethoxy) silane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropyltripropoxy Silane, γ-mercaptopropyltributoxysilane and the like.

In the present invention, co-hydrolysis means hydrolysis in which hydrolysis of a tetraalkyl silicate or the like and a functional alkyl silicate is performed in parallel.
Therefore, in the co-hydrolysis in the present invention, in addition to the mode in which the tetraalkyl silicate and the functional alkyl silicate coexist to start the hydrolysis of both at the same time, one of the hydrolysis is started and the hydrolysis ends. A mode in which the other is added before and the hydrolysis is continued is included.

However, in the embodiment in which the hydrolysis of the tetraalkyl silicate or the like and the functional alkyl silicate are simultaneously started, or in the embodiment in which the alkyl silicate is hydrolyzed first, the hydrolysis of the tetraalkyl silicate alone is more likely. The reaction proceeds much, and the residual amount of the unreacted functional alkyl silicate increases, the white fine powder is contained in the silicate oligomer, and sometimes the whole reaction system gels.

In the present invention, it is important to add a tetraalkyl silicate or the like to the above-mentioned hydrolysis product of the functional alkyl silicate to carry out polycondensation or hydrolysis. That is, tetraalkyl silicate, etc.
Since the compound is a tetrafunctional compound, when the hydrolysis is completed, a gel is easily generated by a dehydration condensation reaction between silanol groups. On the other hand, since the above-mentioned functional alkyl silicate is a compound having three or less functional groups, silanol groups remain relatively stably even after the hydrolysis is completed. Then, the silanol group reacts with a tetraalkyl silicate or an oligomer obtained by partially hydrolyzing the tetraalkyl silicate to perform a dealcoholization reaction, thereby generating a silicate oligomer. In addition, silicate oligomers are also generated by adding water and performing hydrolysis.

The proportion of the tetraalkyl silicate or the like and the functional alkyl silicate (or the hydrolysis product of the functional alkyl silicate) used in the hydrolysis is appropriately determined depending on the amount of the functional group to be introduced into the silicate oligomer. However, for example, in order to obtain a silicate oligomer having sufficient compatibility with the resin, the use ratio of the functional alkyl silicate (or the hydrolysis product of the functional alkyl silicate) is limited to tetraalkyl as the amount of the functional alkyl silicate. It is preferable to select from a range of 0.1 to 20 times the mole of silicate or the like.

The hydrolysis must be carried out under conditions that can protect the functional groups of the functional alkyl silicate. Specific conditions for such hydrolysis are appropriately selected depending on the type of the functional group. However, in each case,
It is preferred to carry out the hydrolysis in the presence of a solvent. In the case of co-hydrolysis, a solvent capable of dissolving not only water but also a functional alkyl silicate is suitably used. Specific examples of such a solvent include tetrahydrofuran, acetone, methyl ethyl ketone, dioxane, and the like.

The minimum amount of the solvent depends on the type of the functional alkyl silicate. That is, for example, in the case of a functional alkyl silicate having a high self-polymerization property such as vinyl silane, a solid powder may be generated and mixed in a silicate oligomer generated unless a large amount of a solvent is used. In the case of a functional alkyl silicate having a low self-polymerization property such as glycidoxypropyltrimethoxysilane, formation of a solid content can be prevented by using only a small amount of a solvent. Accordingly, the amount of the solvent to be used is determined in consideration of the degree of self-polymerization of the functional alkyl silicate. .
It is preferable to select from the range of 5 to 50 times by weight.

As the catalyst, acidic compounds such as hydrochloric acid, phosphoric acid, sulfuric acid, paratoluenesulfonic acid, xylenesulfonic acid and the like, basic compounds of tertiary amine, tertiary ammonium salt and quaternary ammonium salt are used. Preferred catalysts are acidic compounds. When the storage stability and curing speed of the silicate oligomer are controlled in a wide range, it is most preferable to use hydrochloric acid which can be easily removed from the silicate oligomer. Usually, the amount of the catalyst used is appropriately selected from the range of 5.times.10@-6 to 1.times.10@-2 weight times based on all silicate components.

The amount of water used must be appropriately selected depending on the type of the alkyl silicate and the functional alkyl silicate. That is, when the amount of water used is too small, the hydrolysis of the functional alkyl silicate does not proceed sufficiently, and a large amount of unreacted material remains in the silicate oligomer. On the other hand, if your water usage is too high,
It gels at an early stage, and the polymerization reaction between the alkyl silicate or the like and the functional alkyl silicate may become difficult. In general, the amount of water used is appropriately selected from the range of 0.1 to 4 equivalent times based on the functional alkyl silicate.

The temperature and time of the hydrolysis cannot be specified unequivocally because they vary significantly depending on the mode of hydrolysis and the type of the functional alkyl silicate. However, for example, in the embodiment in which the hydrolysis of the functional alkyl silicate is started and then the hydrolysis is continued by adding the alkyl silicate, when the alkoxy group of the functional alkyl silicate is methyl, at 20 ° C. for 30 minutes or more, In the case of a butyl group, by refluxing for 1 hour or more at the boiling point of the solvent, a silanol group necessary for a polymerization reaction between an alkyl silicate or the like and a functional alkyl silicate can be sufficiently generated. In this case, the alkyl silicate is added and refluxed to cause a reaction between the silanol group and the alkyl silicate, and then the polymerization is allowed to proceed while flowing out the solvent to produce the high molecular weight oligomer of the present invention.

The molecular weight of the silicate oligomer in the present invention can be easily adjusted by controlling the rate of hydrolysis. In the present invention, the molecular weight of the silicate oligomer is 500 to 100,000, preferably 1
It is necessary to be in the range of 000 to 50,000. When the molecular weight exceeds 100,000, handling becomes difficult.

The silicate oligomer in the present invention is
Because it has better compatibility with various resins than conventional unmodified silicates, it can be mixed with resins such as polyethylene, polypropylene, polyester, polycarbonate, polyamide, polyvinyl chloride, polyurethane, epoxy, and phenol to physically Can be used to change mechanical properties.

In particular, in the case of a silicate oligomer having a functional group containing an epoxy group, the silicate oligomer is suitable for resins such as an epoxy resin, polyester, polycarbonate, polyamide, and polyurethane. In the case, polyethylene, polypropylene, suitable for resins such as polyvinyl chloride,
A silicate oligomer having a functional group containing a mercapto group is suitable for a resin such as polyester, polycarbonate, polyamide, polyurethane, epoxy, and phenol.

Also, silica, clay, glass, talc,
The surface of an inorganic material such as kaolin, calcium carbonate, calcium silicate, and aluminum powder is treated to improve the adhesion between the inorganic material and the resin, and can be used as a primer for maintaining the performance at a high level for a long time. Furthermore, the silicate oligomer in the present invention can be used alone, but it is also possible to use a functional group in the silicate oligomer and convert it into a graft polymer starting from the functional group.

[0032]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention. In the following examples, the molecular weight of the silicate oligomer was determined by measuring the molecular weight distribution according to the conditions of GPC described in the main section.

Example 1 First, γ-glycidoxypropyltrimethoxysilane 2
36 g (1 mol, 3 equivalents) was dissolved in 500 g of tetrahydrofuran (hereinafter abbreviated as “THF”), and 54 g (6 equivalents) of a 0.35% aqueous hydrochloric acid solution was added to the obtained solution, followed by mixing at 20 ° C. For 1 hour to effect hydrolysis. Next, 450 g of polymethoxysiloxane (Mitsubishi Chemical's product "M-51": a product obtained by hydrolyzing tetramethoxysilane by 50%) was added to the above reaction solution, and the mixture was refluxed for 2 hours. Thereafter, the temperature is raised to 150 ° C. and TH
F was allowed to flow out to obtain a colorless and transparent silicate oligomer liquid.

The above silicate oligomer is mainly composed of 50
It consists of molecular weight components from 0 to 100,000, and the main peak is 1
0000 and 5000. The epoxy equivalent was measured by the tetraammonium bromide-perchloric acid method, and was found to be 609 g / eq. This value was approximately 1% of the theoretical value calculated from the amount of γ-glycidoxypropyltrimethoxysilane used. It was confirmed that cleavage of the epoxy group did not occur in the above reaction. The raw material polymethoxysiloxane (“M-51”) has a molecular weight of 4
It is an oligomer centered at 00.

Example 2 First, 148 g of vinyltrimethoxysilane (1 mol, 3 mol
Was dissolved in 500 g of THF and 0.1 g was added to the resulting solution.
36 g (4 equivalents) of 35% hydrochloric acid aqueous solution was added and mixed,
Hydrolysis was carried out by allowing to stand at 20 ° C. for 1 hour. Then
The above reaction solution was mixed with polymethoxysiloxane (“M-5”).
1 ") 450 g was added and refluxed for 2 hours. Thereafter, the temperature was increased to 150 ° C., and THF was allowed to flow out to obtain a slightly brown transparent silicate oligomer liquid. The silicate oligomers described above consisted primarily of molecular weight components of 500-100,000, with major peaks at 10,000 and 5,000.

Example 3 First, 220 g (1 mol, 3 equivalents) of γ-glycidoxypropylmethyldimethoxysilane was dissolved in 500 g of THF, and 72 g (8 equivalents) of a 0.35% aqueous hydrochloric acid solution was added to the obtained solution. And left to stand at 20 ° C. for 1 hour to effect hydrolysis. Next, 450 g of polymethoxysiloxane ("M-51") was added to the above reaction solution, and the mixture was refluxed for 2 hours. Thereafter, the temperature is raised to 150 ° C. and TH
F was allowed to flow out to obtain a colorless and transparent silicate oligomer liquid. The above silicate oligomer is mainly 500 to 1
Consisting of a molecular weight component of 00000, the main peak being 1000
Were at 0 and 5000.

Example 4 First, 245 g (1 mol, 3 equivalents) of β (3,4 epoxycyclohexyl) ethyltrimethoxysilane was added to THF 5
The resulting solution was mixed with 54 g (6 equivalents) of a 0.35% hydrochloric acid aqueous solution, and left at 20 ° C. for 1 hour to carry out hydrolysis. Next, 450 g of polymethoxysiloxane ("M-51") was added to the above reaction solution, and the mixture was refluxed for 2 hours. Thereafter, the temperature was raised to 150 ° C., and THF was flown out to obtain a colorless and transparent silicate oligomer liquid. The silicate oligomers described above consisted primarily of molecular weight components of 500-100,000, with major peaks at 10,000 and 5,000.

Example 5 First, γ-glycidoxypropyltrimethoxysilane 2
36 g (1 mol, 3 equivalents) are dissolved in 500 g of THF,
63 g (7 equivalents) of a 0.35% hydrochloric acid aqueous solution was added to the obtained solution.
Was added and mixed, and the mixture was left standing at 20 ° C. for 1 hour to perform hydrolysis. Then, polymethoxysiloxane (M-41, a product obtained by hydrolyzing 40% of tetramethoxysilane) was added to the above reaction solution.
50 g was added, and the mixture was refluxed for 2 hours. Then 15
The temperature was raised to 0 ° C., and THF was flown out to obtain a colorless and transparent silicate oligomer liquid. The silicate oligomers described above consisted primarily of molecular weight components of 500-100,000, with major peaks at 10,000 and 5,000.

Example 6 236 g of γ-glycidoxypropyltrimethoxysilane
(1 mol, 3 equivalents) was dissolved in 500 g of THF, 54 g (6 equivalents) of a 0.35% aqueous hydrochloric acid solution was added to the obtained solution, mixed, and left at 20 ° C. for 1 hour to carry out hydrolysis. Next, polymethoxysiloxane (M-60, a product obtained by hydrolyzing tetramethoxysilane by 60%) was added to the above reaction solution.
50 g was added, and the mixture was refluxed for 2 hours. Then 15
The temperature was raised to 0 ° C., and THF was flown out to obtain a colorless and transparent silicate oligomer liquid. The silicate oligomers described above consisted primarily of molecular weight components of 500-100,000, with major peaks at 10,000 and 5,000.

Example 7 236 g of γ-glycidoxypropyltrimethoxysilane
(1 mol, 3 equivalents) was dissolved in 500 g of THF, 63 g (7 equivalents) of a 0.35% aqueous hydrochloric acid solution was added to the obtained solution, mixed, and left at 20 ° C. for 1 hour to carry out hydrolysis. Then, tetrabutoxysilane was added to the above reaction solution for 6 hours.
Add 500 g of 0% hydrolyzed oligomer and add 10 g
Refluxed for hours. Thereafter, the temperature was raised to 150 ° C., and THF was flown out to obtain a colorless and transparent silicate oligomer liquid. The above silicate oligomers are mainly 50
It consists of molecular weight components from 0 to 100,000, and the main peak is 1
0000 and 5000.

Example 8 236 g of γ-glycidoxypropyltriethoxysilane
(1 mol, 3 equivalents) was dissolved in 500 g of THF, 63 g (7 equivalents) of a 0.35% hydrochloric acid aqueous solution was added to the obtained solution, mixed, and refluxed for 1 hour to carry out hydrolysis. Next, 500 g of an oligomer obtained by hydrolyzing 50% of tetraethoxysilane was added to the above reaction solution, and the mixture was refluxed for 4 hours. Thereafter, the temperature was raised to 150 ° C., and THF was flown out to obtain a colorless and transparent silicate oligomer liquid.
The above silicate oligomer is mainly 500 to 1000
The main peaks are 10,000 and 5
000.

Comparative Example 1 236 g of γ-glycidoxypropyltrimethoxysilane
(1 mol, 3 equivalents) was dissolved in 500 g of THF, and 54 g (6 equivalents) of a 0.35% hydrochloric acid aqueous solution and 450 g of polymethoxysiloxane (“M-51”) were added to the obtained solution, followed by refluxing for 2 hours. Hydrolysis was performed. Then 150
The temperature was raised to ° C. and THF was allowed to flow. A clear liquid was formed at the beginning of the THF outflow. Thereafter, as the THF disappeared, a white solid was generated. And finally, a silicate oligomer liquid containing white fine powder was obtained.
The above solid product consisted mainly of molecular weight components of 500 to 100,000, with main peaks at 10,000 and 5000.

[0043]

According to the present invention described above, silicate oligomers having excellent compatibility with various resins are provided. Such silicate oligomers include, for example,
It can be suitably used as a physical property improver for various resins and a surface modifier for various inorganic materials.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08G 77/00-77/62

Claims (2)

(57) [Claims] 1. A method for producing a silicate oligomer having a functional group and a molecular weight in terms of polystyrene measured by GPC of from 500 to 100,000, comprising a tetraalkyl silicate having an alkyl group having 1 to 4 carbon atoms or In co-hydrolyzing an oligomer obtained by partial hydrolysis and a functional alkyl silicate represented by the following chemical formula [Chemical Formula 1], the hydrolysis product of the functional alkyl silicate has an alkyl group having 1 to 4 carbon atoms. A polyalkylene silicate or an oligomer obtained by partially hydrolyzing the same to perform polycondensation or hydrolysis. Embedded image (Wherein, R ¹ is a functional group, R ² is an alkyl group or an alkoxyalkyl group having 1 to 10 carbon atoms, R ³ is a functional group or an alkyl group, m is an integer of 1 to 3, n is an integer of 0 or 1, Represents) 2. The method for producing a silicate oligomer according to claim 1, wherein the hydrolysis is carried out in the presence of a solvent.