JP2015074628A - Method of producing (meth)acrylamide alkyl alkoxysilane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce highly stable (meth)acrylamide alkyl alkoxysilane with high yield.SOLUTION: A method of producing (meth)acrylamide alkyl alkoxysilane (1) is provided which comprises: a step of continuously or intermittently adding aminoalkyl alkoxysilane (3) to (meth)acrylic acid ester (2) in the presence of an amidation catalyst thereby reacting the aminoalkyl alkoxysilane (3) and the (meth)acrylic acid ester (2) with each other; and a treatment step of treating the reaction mixture by an adsorbent. (1) (2) (3), where Rto Rand Rrepresent H or a C1 to C12 hydrocarbon group, Rrepresents a C1 to C6 alkyl group, a C1 to C6 aminoalkyl group, 6 to 12 aryl group or a silyl functional group, Rand Rrepresent a C1 to C12 hydrocarbon group, Rrepresents a bivalent hydrocarbon group and x represents an integer of 0 to 2.

Description

  The present invention relates to a method for producing (meth) acrylamide alkylalkoxysilane. The (meth) acrylamide alkylalkoxysilane obtained by the method of the present invention is useful as a coupling agent, and the method for producing (meth) acrylamide alkylalkoxysilane of the present invention is an improved production method.

  Silanes having a methacrylate functional group are known. For example, 3-methacryloxypropyltrimethoxysilane has been used as a component of various thermoplastic glass fiber reinforced composite materials and coatings that improve the durability of metal supports. Conventionally, in the field where 3-methacryloxypropyltrimethoxysilane is used, further improvement in its performance has been demanded. And due to differences in the molecular structure of silanes, for example, hydrolysis rate, water solubility, low product coloration, lubricity, etc., the processability of the substrate to be treated, static control, fiber strength, fiber drawing rate It is known that various performance differences occur. And the methacrylamide alkyl alkoxysilane which changed the structure of 3-methacryloxypropyl trimethoxysilane partially has the outstanding performance.

  Patent Document 1 describes a method for producing an acrylamide alkylalkoxysilane by reaction with an acrylic ester of aminoalkylsilane.

  Patent Document 2 describes a method for producing an acrylamidoalkylalkoxysilane by dropping an acrylic acid ester onto an aminoalkylsilane in the presence of an amidation catalyst. According to this method, acrylamidoalkylalkoxysilane is obtained with a yield of 80% or more.

Japanese Patent Publication No. 55-92393 Japanese Patent No. 3561501

However, the conventional method for producing acrylamide alkyl alkoxysilane still has problems. The reaction conditions described in U.S. Patent No. 6,057,037 are reactions in which Michael addition of amine groups to acrylate double bonds occurs, and the product lacks methacrylic ester functionality. Moreover, according to the method described in Patent Document 2, although a yield of 80% or more is obtained, there is still room for improvement in yield.
Moreover, the (meth) acrylamide alkyl alkoxysilane obtained by the conventional manufacturing method may be colored with time at high temperatures, and there is a problem in stability.

(一般式（１）〜（３）中
Ｒ^１〜Ｒ^３、及びＲ^５はそれぞれ独立に水素原子または炭素数１〜１２の炭化水素基を表す。
Ｒ^４は水素原子、炭素数１〜６のアルキル基、炭素数１〜６のアミノアルキル基、６〜１２のアリール基、又はシリル官能基を表す。
Ｒ^６及びＲ^８は炭素数１〜１２の炭化水素基を表す。
Ｒ^７は、二価の炭化水素基を表す。
ｘは０〜２の整数を表す。)
〔２〕 吸着剤が活性炭、ゼオライト、シリカ、チタニアより選択される少なくとも１種である〔１〕に記載の製造方法；
〔３〕 反応工程を行いながら処理工程を行い、吸着剤での処理がアルコールの除去を含む〔１〕に記載の製造方法；
を提供することにより達成される。 The inventor has intensively studied to improve the yield of (meth) acrylamide alkylalkoxysilane. As a result, by treating the reaction mixture with an adsorbent, it became possible to produce (meth) acrylamide alkylalkoxysilane having excellent stability without coloring even at high temperatures. Further, the reaction proceeds preferably while removing the by-produced alcohol by reacting the (meth) acrylic acid ester with aminoalkylalkoxysilane while treating the reaction mixture with an adsorbent, which affects storage stability. The inventors have found that (meth) acrylamide alkylalkoxysilane can be obtained in a high yield and industrially advantageously by suppressing the generation of by-products, and the present invention has been completed.
That is, the present invention
[1] A method for producing (meth) acrylamide alkylalkoxysilane represented by the following general formula (1),
In the presence of an amidation catalyst, the reaction is carried out by continuously or intermittently adding an aminoalkylalkoxysilane represented by the following general formula (3) to the (meth) acrylic acid ester represented by the following general formula (2). A reaction step, and
A process for producing (meth) acrylamide alkylalkoxysilane, comprising a treatment step of treating the reaction mixture with an adsorbent;

(In the general formulas (1) to (3), R ^{1 to} R ³ and R ⁵ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.
R ⁴ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aminoalkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a silyl functional group.
R ⁶ and R ⁸ represent a hydrocarbon group having 1 to 12 carbon atoms.
R ⁷ represents a divalent hydrocarbon group.
x represents an integer of 0-2. )
[2] The production method according to [1], wherein the adsorbent is at least one selected from activated carbon, zeolite, silica, and titania;
[3] The production method according to [1], wherein the treatment step is performed while the reaction step is performed, and the treatment with the adsorbent includes removal of alcohol;
Is achieved by providing

  According to the present invention, it is useful as a coupling agent, suppresses the generation of by-products that affect stability, and produces (meth) acrylamide alkylalkoxysilanes in a high yield and industrially advantageously. it can.

Hereinafter, the contents of the present invention will be described in detail. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.
In the description of the group (atomic group) in this specification, the description which does not describe substitution and unsubstituted includes what has a substituent with what does not have a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
(Meth) acrylic acid means acrylic acid and / or methacrylic acid.

The production method of the present invention is a method for producing (meth) acrylamide alkylalkoxysilane represented by the following general formula (1),
In the presence of an amidation catalyst, the reaction is carried out by continuously or intermittently adding an aminoalkylalkoxysilane represented by the following general formula (3) to the (meth) acrylic acid ester represented by the following general formula (2). A reaction step, and
A treatment step of treating the reaction mixture with an adsorbent.

(In the general formulas (1) to (3), R ^{1 to} R ³ and R ⁵ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.
R ⁴ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aminoalkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a silyl functional group.
R ⁶ and R ⁸ represent a hydrocarbon group having 1 to 12 carbon atoms.
R ⁷ represents a divalent hydrocarbon group.
x represents an integer of 0-2. )

[General formulas (1) to (3)]
The hydrocarbon group having 1 to 12 carbon atoms represented by R ^{1 to} R ³ in the general formula (1) is preferably an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms, for example, methyl Group, ethyl group, propyl group, isopropyl group, butyl group, vinyl group, phenyl group and the like. Among them, a methyl group, a vinyl group or a phenyl group is preferable, and a methyl group is particularly preferable.
The hydrocarbon group having 1 to 12 carbon atoms represented by R ⁵ and R ⁶ is preferably an alkyl group having 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group. It is done. Of these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable.

R ⁴ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aminoalkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a silyl functional group, and may be substituted with an alkyl group or an amino group. A good hydrocarbon group having 1 to 6 carbon atoms is represented. For example a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, a phenyl _{group, -C 2 H 4 NH 2,} -C 2 H 4 NHCH 2 CH 3, -C 2 H 4 NHC 6 H 5, -CH 2 C (CH _{3) 3,} and _{-C 3 H 6 Si (OCH 3} ) 2 CH 3 and the like, it is preferable that among others a hydrogen atom.
R ⁷ represents a divalent hydrocarbon group, preferably an alkylene group, more preferably an alkylene group having 1 to 6 carbon atoms, and still more preferably an alkylene group having 2 to 5 carbon atoms. For example, — (CH ₂ ) ₃ —, —CH ₂ —CH (CH ₃ ) —CH ₂ —, — (CH ₂ ) ₂ O (CH ₂ ) ₂ —, — (CH ₂ ) ₂ C ₆ H ₄ (CH ₂ ) _2- , and-(CH ₂ ) ₂ cyclo-C ₆ H _10- (CH ₂ ) _2- and the like, among others-(CH ₂ ) _3- , or -CH ₂ -CH (CH ₃ ) -CH ₂ - is preferably, _{- (CH} 2) 3 - and more preferably (1,3-propylene group).

R < ¹ > -R < ⁷ > in General formula (2) and (3) is synonymous with R < ¹ > -R < ⁷ > in General formula (1), and its preferable thing is also the same.
The hydrocarbon group having 1 to 12 carbon atoms represented by R ⁸ is preferably an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or isopropyl. Group, butyl group, vinyl group, phenyl group and the like. Among them, a methyl group, a vinyl group or a phenyl group is preferable, and a methyl group is particularly preferable.
X in general formula (1) and (3) represents the integer of 0-2, 0 or 1 is preferable and 0 is more preferable.

  The (meth) acrylic acid ester represented by the general formula (2) and the aminoalkylalkoxysilane represented by the general formula (3) used in the production method of the present invention are readily available compounds and are commercially available. Can be used.

The (meth) acrylic acid ester represented by the general formula (2) is preferably methyl methacrylate, ethyl methacrylate, propyl methacrylate, methyl crotonic acid, ethyl crotonic acid, (CH ₃ ) ₂ C═CHCO ₂ CH ₃ CH ₃ CH═C (CH ₃ ) CO ₂ CH _{3 and the} like. More preferred is methyl methacrylate or ethyl methacrylate.

  The aminoalkylalkoxysilane represented by the general formula (3) is preferably aminopropyltrimethoxysilane, aminopropyltriethoxysilane, aminopropylmethyldimethoxysilane, aminopropylmethyldiethoxysilane, aminobutyltrimethoxysilane, aminobutyl. Triethoxysilane, aminobutylmethyldimethoxysilane, aminobutylmethyldiethoxysilane, aminoethylaminopropyltrimethoxysilane, aminoethylaminopropyltriethoxysilane, aminoethylaminopropylmethyldimethoxysilane, aminoethylaminopropylmethyldiethoxysilane N -Methylaminopropyltrimethoxysilane, aminopropyldimethylmethoxysilane, bis- (γ-trimethoxysilylpropyl) amino And other (meth) aminoalkyl alkoxysilane capable of forming an amide in a reaction with acrylic acid esters, aminoalkyl alkoxysilane. More preferred is aminopropyltrimethoxysilane or aminopropyltriethoxysilane.

  The (meth) acrylic acid ester represented by the general formula (2) and the aminoalkylalkoxysilane represented by the general formula (3) form (meth) acrylamide alkylalkoxysilane by reaction. Moreover, alcohol produces | generates by the exchange reaction with the alkoxy group couple | bonded with a silicon atom in that case, and forms a mixture with (meth) acrylamide alkyl alkoxysilane.

  The reaction between the (meth) acrylic acid ester represented by the general formula (2) and the aminoalkylalkoxysilane represented by the general formula (3) is a (meth) acrylic acid ester represented by the general formula (2). It is preferable to use an excessive amount of from the viewpoint of yield. The molar ratio of the (meth) acrylic acid ester represented by the general formula (2) to the aminoalkylalkoxysilane represented by the general formula (3) may be 1.01 to 2.0 or more. .1 to 1.7 is preferable, and 1.25 to 1.45 is more preferable.

[Amidation catalyst]
The amidation catalyst is a catalyst capable of forming (meth) acrylamidoalkylalkoxysilane from (meth) acrylic acid ester represented by general formula (2) and aminoalkylalkoxysilane represented by general formula (3). And preferably a Lewis acid, more preferably a Lewis acid containing a metal selected from a compound of tin, titanium, aluminum, cobalt, zinc, iron or lead, and more preferably dibutyltin dilaurate, octanoic acid A tin compound selected from the group consisting of stannous and dibutyltin oxide, and most preferably dibutyltin oxide.
The amount of the amidation catalyst used is preferably 0.0005 to 0.02 mol times, more preferably 0.001 to 0.01 mol with respect to the aminoalkylalkoxysilane represented by the general formula (3). And most preferably 0.002 to 0.005 mole times.

(Polymerization inhibitor)
The production method of the present invention is preferably carried out in the presence of a polymerization inhibitor. As such polymerization inhibitors, those usually used as polymerization inhibitors for (meth) acrylic acid esters can be suitably used. For example, p-methoxyphenol, hydroquinone, methoxybenzoquinone, phenothiazine, catechols, alkylphenols. And alkyl bisphenols, zinc dimethyldithiocarbamate, copper dimethyldithiocarbamate, copper dibutyldithiocarbamate, copper salicylate, thiodipropionic esters, mercaptobenzimidazoles, phosphites, etc. Hydroquinone, catechols and phenols are preferred, and hydroquinone is more preferred.
The amount of the polymerization inhibitor used is preferably 0.001 to 1 mol times, more preferably 0.002 to 0.5 mol times with respect to the aminoalkylalkoxysilane represented by the general formula (3). Yes, most preferably 0.005 to 0.1 mole times.

[Reaction process]
In the production method of the present invention, preferably, a reaction vessel is charged with an amidation catalyst, a (meth) acrylic acid ester represented by the general formula (2), and, if desired, a polymerization inhibitor and a solvent. It heats to reaction temperature, stirring, and carries out by the method of adding the aminoalkyl alkoxysilane represented by General formula (3) continuously or intermittently. The specific method of “adding continuously or intermittently” is preferably carried out by dropping the aminoalkylalkoxysilane represented by the general formula (3). The dropping time is not particularly limited in a strict sense, and may vary depending on the scale of the reaction. However, it is usually preferably in the range of 0.5 to 30 hours, preferably 3 to 15 hours. A range is more preferable.

The reaction temperature is in the range of 50-200 ° C, more preferably 70-160 ° C, and most preferably 90-140 ° C. Since the production method of the present invention can remove by-produced alcohol by the processing steps described later, (meth) acrylamidoalkylalkoxysilane can be obtained in a high yield in the above temperature range lower than that of the conventional method. Moreover, it is industrially advantageous to make it react at low reaction temperature.
The reaction pressure is not particularly limited and can be carried out under reduced pressure, normal pressure, or increased pressure, but is preferably under reduced pressure or normal pressure, and more preferably within a range of 13.3 kPa to 101.3 kPa. preferable.
The reaction is preferably performed under an inert atmosphere, and more preferably performed under nitrogen.

  As the reactor, a reaction vessel used in industry can be used without any particular limitation. Preferably, a supply device, a stirrer, a reaction temperature control mechanism, a steam cooler, an inert gas supply mechanism, a reaction solution transport of one or more reaction raw materials (particularly aminoalkylalkoxysilane represented by the general formula (3)) What is necessary is just a reactor which has apparatuses (liquid feed pump etc.).

The production method of the present invention can be carried out in the presence or absence of a solvent, and it is not necessary to use a solvent, but a solvent can also be used for adjusting the temperature or viscosity of the reaction solution. The solvent that can be used when the reaction is carried out in the presence of a solvent is not particularly limited as long as it does not participate in the reaction, and examples thereof include aromatic hydrocarbons such as toluene and xylene, ethers such as diisopropyl ether and tetrahydrofuran. Can be mentioned.
When using a solvent, the content of the product in the reaction solution is preferably 60% or more, more preferably 75% or more, most preferably 90% or more, and the solvent content is preferably 25%. Less than, most preferably less than 10%. From the viewpoint of reducing solvent costs and improving productivity, it is preferable to carry out the production method of the present invention without using a solvent.

[Processing process]
The production method of the present invention includes the aforementioned reaction step and a treatment step of treating the reaction mixture with an adsorbent.
Examples of the adsorbent include activated carbon, zeolite, silica, titania and the like, and activated carbon is preferable. Examples of the activated carbon include commercial products such as “Kuraray Coal” (trade name, manufactured by Kuraray Chemical Co., Ltd.).
As a method of treating the reaction mixture with the adsorbent, there are a method in which the adsorbent is added to the reaction mixture and stirring, a method in which the column is filled with the adsorbent, a method of passing through the liquid, a method in which the distillation tower is packed with the adsorbent and distilled. Can be mentioned. In the present invention, a method of stirring after adding an adsorbent to the reaction mixture is preferred.

  The amount of the adsorbent used can be appropriately changed depending on the type of the adsorbent and is not particularly limited, but is preferably 0.001 to 0.05 times by mass with respect to the reaction mixture.

  In the production method of the present invention, the treatment step may be performed after the reaction step, or the treatment step may be performed while the reaction step is performed, and the treatment step is preferably performed while the reaction step is performed. For example, after completion of the amine addition, activated carbon can be added to the reaction solution, and the reaction can be allowed to proceed while removing the alcohol produced by the reaction with the adsorbent. Thereby, (meth) acrylamide alkyl alkoxysilane can be obtained with a high yield, and the obtained (meth) acrylamide alkyl alkoxysilane is excellent in stability.

  The treatment temperature in the treatment step is preferably 0 to 150 ° C, and more preferably 40 to 100 ° C. If it is said temperature range, reaction can further be advanced, removing the alcohol produced | generated by reaction with adsorption agent.

  Although the processing time in a processing process does not have a restriction | limiting in particular, It is preferable that it is 10 to 120 minutes, and it is more preferable that it is 30 to 60 minutes.

  The (meth) acrylamide alkylalkoxysilane obtained after completion of the reaction can be isolated by a method usually used in the isolation and purification of organic compounds. For example, the target (meth) acrylamidoalkylalkoxysilane can be obtained by separating from the adsorbent from the reaction mixture, followed by distillation under reduced pressure. Since the production method of the present invention has a treatment step of treating with an adsorbent, it is possible to obtain (meth) acrylamide alkylalkoxysilane having high purity and excellent stability without coloring even at high temperatures in a high yield. it can.

  EXAMPLES Hereinafter, although a reference example, an Example, and a comparative example demonstrate this invention concretely, this invention is not limited to these Examples.

<Example 1>
Hydroquinone 1.3 g (0.01 mol), dibutyltin oxide 0.90 g (0.0036 mol), methyl methacrylate 130 g (1.3 mol) in a three-necked flask with an internal volume of 500 ml equipped with a stirrer, thermometer and distillation tower. ) And heated to an internal temperature of 100 ° C. with stirring. When refluxed, 179 g (1.0 mol) of 3-aminopropyltrimethoxysilane was added dropwise over 7.4 hours. The reaction was carried out while distilling off the methanol produced. After stirring for 3 hours under reflux conditions, the mixture was cooled to room temperature. The reaction mixture contained 245 g (0.99 mol) of N-trimethoxysilylpropylmethacrylamide.
The obtained reaction mixture was charged with 4.9 g of activated carbon (Kuraray Coal; trade name, manufactured by Kuraray Chemical Co., Ltd.) and heated to an internal temperature of 50 ° C. with stirring. After stirring at an internal temperature of 50 ° C. for 30 minutes, the activated carbon was removed by filtration. The filtrate was distilled to obtain 235 g (0.95 mol) of N-trimethoxysilylpropylmethacrylamide. This is a 95% yield based on 3-aminopropyltrimethoxysilane.

<Comparative Example 1>
In the same manner as in Example 1, the reaction mixture was directly distilled without charging activated carbon to obtain 236 g (0.95 mol) of N-trimethoxysilylpropylmethacrylamide. This is a 95% yield based on 3-aminopropyltrimethoxysilane.

<Evaluation Example 1>
When N-trimethoxysilylpropyl methacrylamide obtained in Example 1 was heated at 60 ° C. for 4 hours, the liquid remained transparent.
<Evaluation Example 2>
When N-trimethoxysilylpropylmethacrylamide obtained in Comparative Example 1 was heated at 60 ° C. for 4 hours, it was colored yellow.

Claims (3)

A method for producing (meth) acrylamide alkylalkoxysilane represented by the following general formula (1):
In the presence of an amidation catalyst, the reaction is carried out by continuously or intermittently adding an aminoalkylalkoxysilane represented by the following general formula (3) to the (meth) acrylic acid ester represented by the following general formula (2). A reaction step, and
A method for producing (meth) acrylamide alkylalkoxysilane, comprising a treatment step of treating a reaction mixture with an adsorbent.

(In the general formulas (1) to (3), R ^{1 to} R ³ and R ⁵ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.
R ⁴ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aminoalkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a silyl functional group.
R ⁶ and R ⁸ represent a hydrocarbon group having 1 to 12 carbon atoms.
R ⁷ represents a divalent hydrocarbon group.
x represents an integer of 0-2. )   The production method according to claim 1, wherein the adsorbent is at least one selected from activated carbon, zeolite, silica, and titania.   The production method according to claim 1, wherein the treatment step is performed while the reaction step is performed, and the treatment with the adsorbent includes removal of alcohol.