JP2778403B2 - Method for producing (meth) acrylic group-containing organopolysiloxane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an industrially advantageous method for producing an organopolysiloxane containing an acryl group or a methacryl group (hereinafter collectively referred to as a (meth) acryl group).

[0002]

2. Description of the Related Art
As a method for producing a (meth) acrylic group-containing organopolysiloxane, for example, a (meth) acrylate compound having an OH group and an organopolysiloxane having a SiX group (X is a halogen atom) are subjected to a de-HX reaction in the presence of a base. Thus, a method for introducing a (meth) acryl group into an organopolysiloxane is known (Japanese Patent Publication No. 58-53).
656).

However, in the (meth) acrylic group-containing organopolysiloxane produced by this method, since the siloxane chain and the (meth) acrylic group are connected by a Si—O—C bond, moisture, acidic impurities, bases This bond may be hydrolyzed under the influence of a sexual impurity or the like, and there is a problem in the stability of the organopolysiloxane.

[0004] On the other hand, a method for producing a polysiloxane chain and a (meth) acrylic group connected by a Si—C bond instead of a Si—O—C bond has been proposed by using an epoxy group of an epoxy group-containing organopolysiloxane and a (meth) acrylic group. A method of introducing a (meth) acryl group by a ring-opening addition reaction with an acryl group is known (JP-A-63-135426,
See JP-A-2-45533).

In this method, in order to obtain an epoxy group-containing organopolysiloxane, an organohydrogenpolysiloxane is first synthesized, and this is subjected to a hydrosilylation reaction with an alkenyl group-containing epoxy compound in the presence of a platinum catalyst. There is a disadvantage that the reaction is required in advance and the reaction is multi-step.

Further, as another production method, there is known a method in which a (meth) acryl compound having an alkenyl group and an organohydrogenpolysiloxane are subjected to a hydrosilylation reaction in the presence of a platinum catalyst (JP-A-48-4800).
0, JP-A-2-163166).

In this method, it is necessary to synthesize an organohydrogenpolysiloxane in advance, and furthermore,
The selectivity of the hydrosilylation reaction between the alkenyl group of the (meth) acryl compound having the alkenyl group and the (meth) acryl group may be problematic. That is, there is no problem when only the alkenyl group selectively undergoes hydrosilylation reaction,
When both the alkenyl group and the (meth) acryl group react with the SiH group of the organohydrogenpolysiloxane, the reaction mixture may gel.

[0008] Further, depending on the combination of an alkenyl group and a (meth) acryl group, (meth)
The reactivity of the acrylic group may be superior, and in this case, the desired (meth) acrylic group-containing organopolysiloxane may not be obtained.

A method for producing a (meth) acrylic group-containing organopolysiloxane in which a polysiloxane chain and a (meth) acrylic group are linked by a Si--C bond is known, but as described above, the conventional method is used. All require a multi-step reaction, and gelation or side reactions are involved during the reaction, making it difficult to easily obtain a polymer having a desired degree of polymerization and a (meth) acrylic group content. There was a need for a solution to this.

The present invention has been made in view of the above circumstances,
One pot, easy and convenient (meta) in one reaction vessel
Provided is a method for producing an organopolysiloxane containing a (meth) acrylic group, which can produce an organopolysiloxane containing an acryl group and can easily produce a product having a desired degree of polymerization without gelation. The purpose is to:

[0011]

The present inventors have made intensive studies to achieve the above object, and as a result, used a silane having a (meth) acrylic group and a hydrolyzable group as a raw material, After the decomposition, the hydrolyzate is polymerized with a diorganocyclosiloxane and a chain organosiloxane oligomer, or the silane is hydrolyzed with a diorganocyclosiloxane, and then the hydrolyzate is converted into a chain organosiloxane oligomer. By co-polymerizing together, a (meth) acrylic group-containing organopolysiloxane can be easily produced in one pot, and the desired degree of polymerization can be obtained simply by changing the mixing ratio of the raw materials.
It has been found that the content of the (meth) acrylic group can be easily adjusted, and the present invention has been accomplished.

Accordingly, the present invention provides a method for hydrolyzing a silane having an acrylic group or a methacrylic group and a hydrolyzable group and then using the hydrolyzate together with a diorganocyclosiloxane and a chain organosiloxane oligomer using an acid catalyst. For producing a (meth) acrylic group-containing organopolysiloxane, characterized in that the silane having an acrylic group or a methacrylic group and a hydrolyzable group are hydrolyzed in the presence of a diorganocyclosiloxane ,
The present invention provides a method for producing a (meth) acrylic group-containing organopolysiloxane, which comprises polymerizing the hydrolyzate together with a chain organosiloxane oligomer using an acid catalyst.

Hereinafter, the present invention will be described in more detail. In the first and second inventions of the present invention, a silane, a diorganocyclosiloxane and a chain having a (meth) acryl group and a hydrolyzable group as starting materials. Is used.

Here, it is preferable to use a silane represented by the following formula (1). ASiR ¹ (OR ² ) ₂ (1) where A is a monovalent hydrocarbon group having a (meth) acrylic group, particularly CH ₂ ＣＲCR ³ COO (CH ₂ ) _a- (R ³ is a hydrogen atom or methyl And the group a is an integer of 1 to 6). In addition, R ¹ is an alkyl group or an aryl group having 1 to 10 carbon atoms, but a methyl group,
It is desirable to use an ethyl group or a phenyl group. R ² is an alkyl group having 1 to 6 carbon atoms, and is preferably a methyl group, an ethyl group or a propyl group from the viewpoint of availability and high reactivity. In this case, specific examples of the functional group A include the following.

[0015]

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The silane is preferably CH ₂特 に CHC
OO (CH ₂ ) ₃ SiCH ₃ (OCH ₃ ) ₂ can be suitably used.

On the other hand, as organocyclosiloxane
The one represented by the following formula (2) is preferably used. (R¹ _TwoSiO)_b ... (2) where R¹Has the same meaning as above, and b has an integer of 3 or more.
Number, specifically (Me_TwoSiO)_Three, (Me_TwoSi
O)_Four, (Me_TwoSiO)_Five, (Me PhSiO)_Four, (P
h_TwoSiO)_FourAnd one or more of these.
The above can be used. In the above formula, Me is methyl
The group Ph represents a phenyl group.

Further, an organosiloxane oligomer is used.
Have a chain structure (having a linear or branched chain
Having a non-cyclic structure).
Using the organosiloxane oligomer represented by (3)
Is recommended. In addition, this organosiloxane
The ligomer is the end portion of the polysiloxane chain and the
It will be a fork. (A_cR¹ _3-cSiO_1/2)_{d + 2}(R¹ _TwoSiO)_e(R¹ SiO_3/2)_d ... (3) where A and R¹Has the same meaning as described above, and c is 0 to
An integer of 3, d and e are integers of 0 or more, preferably d is 0
20, e is 0 to 30.

Examples of such an organosiloxane oligomer include the following.
Species or two or more can be used.

[0020]

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As the organosiloxane oligomer, those having a (meth) acryl group are particularly excellent in the curability when the target organopolysiloxane is cured.

In the first invention of the present invention, first, the silane of the above formula (1) is hydrolyzed. In this hydrolysis, an acid catalyst can be used.
Methanesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, sulfuric acid, hydrochloric acid and the like are used, and methanesulfonic acid is particularly preferred. In the present invention, since the pressure of the reaction system may be reduced after the completion of the first stage of the reaction, it is not preferable to use a volatile acid.

The used amount can be 0.01 to 10 parts with respect to 100 parts (parts by weight, hereinafter the same) of the silane of the formula (1).

In the hydrolysis, water or an aqueous solution of the above-mentioned acid catalyst is used. The amount of water used is an amount sufficient to completely hydrolyze the silane of the formula (1). )
Can be usually 0.1 to 200 parts with respect to 100 parts of silane. The hydrolysis reaction can be carried out by adding a polymerization inhibitor, if necessary.

The hydrolysis may be carried out usually at room temperature.
When the heat generation is severe, the temperature may be cooled to about -10 to 10 ° C.
What is necessary is just to heat to -100 degreeC. The reaction time is not particularly limited.

After the completion of the hydrolysis reaction, it is preferable to remove the alcohol (R ² OH) and excess water generated in the reaction system. As for the method of removal, the reaction mixture is heated and distilled off as it is, or if necessary, may be distilled off under reduced pressure, or may be heated under reduced pressure for distillation. Heating temperature,
The degree of decompression is not limited, but is 30 to 120 ° C. and 10 to 200 ° C.
Torr is sufficient.

Next, an organocyclosiloxane of the formula (2) and a linear organosiloxane oligomer of the formula (3) are added to the reaction mixture obtained by the hydrolysis, and the mixture is polymerized using an acid catalyst. The objective is to obtain the desired (meth) acrylic group-containing organopolysiloxane.

In this case, the weight ratio of the silane of the formula (1) to the organocyclosiloxane of the formula (2) is 0.1 / 9.
The ratio of 9.9 to 99.9 / 0.1, more preferably 0.9.
5 / 99.5 to 50/50, and the linear organosiloxane oligomer of the formula (3) has a total amount of 100% of the silane and siloxane of the formulas (1) and (2).
It is preferred to use from 0.1 to 50 parts per part.

The above-mentioned polymerization reaction can be carried out by heating to 50 to 150 ° C. In this polymerization reaction, the above-mentioned acid catalyst can be further added if necessary. in this case,
The additional amount is usually 10 parts or less based on 100 parts in total of the silane of the formula (1) and the cyclosiloxane of the formula (2). In addition,
The reaction time of the polymerization reaction is not particularly limited.

After the completion of the polymerization reaction, a basic compound is added to the reaction mixture to neutralize the acid catalyst used in the reaction.
Such basic compounds include NaHCO ₃ , Na ₂ C
O ₃ , K ₂ CO ₃ , (C ₂ H ₅ ) ₃ N, (C ₄ H ₉ ) ₃ N, N
H _3, and the like may be used pyridine, filtration of the resulting salts, NaHCO ₃ from safety, Na ₂ CO ₃ is preferred. The amount of these basic compounds used is the amount of neutralization, for example, 0.1 to 100 parts by weight of the cyclosiloxane of the formula (2).
It can be 300 parts. In this case, the neutralization temperature and time are not particularly limited.

After the neutralized salt is filtered from the reaction mixture, volatile components are distilled off under heating and reduced pressure, or the volatile component is heated from the reaction mixture and distilled off under reduced pressure, and then the neutralized salt is filtered. Thereby, a (meth) acryl group-containing organopolysiloxane, which is a product, is obtained.

In the above production method, instead of adding the organocyclosiloxane of the formula (2) at the time of polymerization, the organocyclosiloxane may be charged in advance before the hydrolysis of the silane and subjected to hydrolysis together with the silane (second). invention). In this case, during the process of distilling off alcohol and excess water, the organocyclosiloxane component in the reaction mixture may be azeotropically distilled off depending on the heating temperature and the degree of pressure reduction. Since the siloxane component and the water / alcohol component are separated, it is easy to recover the organocyclosiloxane component from the distillate, which can be returned to the reaction vessel. Other operations and the like are the same as those of the first invention.

[0033]

[0034]

[0035]

[0036]

[0037]

The reaction performed in the production method of the present invention may be performed using an organic solvent. Examples of usable organic solvents include aromatic hydrocarbons such as toluene and xylene, hexane, isooctane, aliphatic hydrocarbons such as industrial gasoline, alcohols such as isopropanol and n-butanol, and methyl isobutyl ketone. Such ketones are exemplified. The reaction atmosphere may be either air or an inert gas.

The (meth) acrylic group-containing organopolysiloxane obtained according to the present invention has, for example, the following formula (4)
Can be indicated by Here, A, R ¹ , c and d have the same meanings as described above, and m
Is an integer of 1 or more and n is an integer of 3 or more, and there is no particular limitation. However, the coatability of the obtained (meth) acrylic group-containing organopolysiloxane on a base material such as paper or plastic film. And m + n = 4 to 3000 is desirable.

Specific examples of the (meth) acrylic group-containing organopolysiloxane that can be produced according to the present invention include the following.

[0041]

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The (meth) acrylic group-containing organopolysiloxane obtained by the production method of the present invention may be used alone or in combination with the same type of organopolysiloxane having a different degree of polymerization or (meth) acryloxy group content. To obtain a radiation-curable organopolysiloxane composition. In this case, various additives may be added to the composition as long as the characteristics are not impaired. For example, acetophenone, benzophenone, 4-chlorobenzophenone, 4,4-dimethoxybenzophenone, 4-methylacetophenone, benzoinmethyl Photoinitiators such as ethers and benzoin trialkylsilyl ethers; oxygen curing inhibitors such as diethylamine, 2-diethylamineethanol and piperidine; reactive diluents such as hexadiol acrylate and trimethylolpropane triacrylate; organic Solvents, leveling agents, fillers,
An antistatic agent, an antifoaming agent, a pigment, an organopolysiloxane and the like can be added.

The radiation-curable organopolysiloxane composition using such a (meth) acrylic group-containing organopolysiloxane is suitable for use as a back surface treatment agent for adhesive tapes, a protective coating agent for metals and plastics, and a base for paints. ing.

In this use, a bar, a gravure coater, a reverse coater or the like or a spray is applied to a metal, such as paper, various plastic films or aluminum, by spraying.
After coating so as to have a film thickness of about 0 μm, this may be irradiated with radiation and cured. As this radiation,
Electron beam, α-ray, β-ray, γ-ray or mercury arc, low-pressure mercury lamp, medium-pressure mercury lamp, ultraviolet light generated from high-pressure mercury lamp, etc. are exemplified. If it is a line, it may be about 2 to 5 Mrad,
In the case of ultraviolet rays, for example, a 2 kW high-pressure mercury lamp (80 watts)
/ Cm) from a distance of 8 cm to 0.01 to 1
Irradiation may be performed for 0 seconds. In the case of ultraviolet irradiation, it is preferable to use the above photopolymerization initiator.

[0045]

According to the present invention, a (meth) acrylic group-containing organopolysiloxane, which conventionally required a multi-step reaction, can be produced in one pot, and only by changing the mixing ratio of the raw materials, A polymer having a desired degree of polymerization and a (meth) acrylic group content can be easily obtained.

[0046]

The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to the following Examples. The parts in the examples are parts by weight, and the viscosity and the refractive index are 2 parts.
It shows the measured value at 5 ° C. Further, the values of curability, peeling force and residual adhesiveness in the examples are values measured by the following test methods.

[Curability] The amount of electron beam irradiation (Mrad) required to form a completely cured film when the organopolysiloxane is applied to a polyethylene laminated paper and then cured by irradiation with an electron beam; In the case of ultraviolet irradiation, the irradiation time (second) required to form a completely cured film by irradiating ultraviolet rays from a distance of 8 cm using two 2 kW high-pressure mercury lamps (80 w / cm) is shown. However, the determination of this curing was made when the coated surface did not fall off even when the coated surface was rubbed with a finger and was not cloudy.

[Releasability] An organopolysiloxane is coated on a polyethylene laminated paper and cured by irradiation with radiation, and then an acrylic resin solvent-type adhesive [Olivine BPS-8170 (Toyo Ink Co., Ltd.) is applied to the cured film surface. And a heat treatment at 100 ° C. for 3 minutes. Then, a bonded paper having a basis weight of 64 g / m ² is stuck on the treated surface and aged at 25 ° C. for 20 hours. Cut to a width of 5 cm, bonded together at a peeling speed of 300 mm / min using a tensile tester at an angle of 180 °, and the force (g / 5c) required to pull and peel the paper.
m) was measured, and this value was used as the initial peel force. Moreover, what was measured after bonding for 3 days at 70 ° C. under a load of 70 g / cm ^{2 under} the above bonding conditions was defined as a temporal peeling force.

[Residual Adhesion Rate] A cured film of an organopolysiloxane was formed on a polyethylene laminated paper in the same manner as in the peeling test, and a polyester tape [Lumirror 31P (trade name, manufactured by Nitto Denko Corporation) was formed on the surface of the cured film. )]
Were heated at 70 ° C. for 20 hours under a load of 20 g / cm ² , and then the tape was peeled off and bonded to a stainless steel plate. Next, the treated tape was peeled off from the stainless steel plate at an angle of 180 ° at a peeling speed of 300 mm / min, the force required for peeling (g / 2.5 cm) was measured, and the untreated standard tape was removed from the stainless steel plate. The force (g / 2.5 cm) required to peel from the untreated standard tape was measured, and the percentage of the force required to peel the untreated standard tape was defined as the residual adhesion ratio.

Example 1 A four-necked flask equipped with a stirrer, thermometer, dropping funnel and reflux condenser was charged with a hydrolyzable silane (29.4 parts) represented by the following formula (5), Octamethylcyclotetrasiloxane (100 parts) represented by (6), methanesulfonic acid (0.13 parts), and dibutylhydroxytoluene (0.07 parts) as a polymerization inhibitor were charged. Water (3.7 parts) was added dropwise at room temperature, and stirring was continued for 3 hours. Thereafter, the flask was heated to 35 to 40 ° C.
Under reduced pressure of 0 Torr, methanol and water in the reaction mixture were distilled off. The liquid separated into two layers accumulated in the aggregator. The upper layer was methanol, the lower layer was octamethylcyclotetrasiloxane, and the lower layer was returned to the flask.

[0051]

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Next, an organosiloxane oligomer (2.2 parts) represented by the following formula (7) and methanesulfonic acid (1.3 parts) were added, heated to 85 to 90 ° C., and polymerized for 8 hours. . After completion of the reaction, sodium hydrogen carbonate (1.7
And heated at 120-130 ° C. for 3 hours. Next, the volatile components were distilled off at 120 to 130 ° C. under a reduced pressure of 2 Torr, and then filtered to obtain a sample 1 (93 parts).

[0053]

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IR spectrum of sample 1, ²⁹ SiNM
From the analysis results of the R and ¹ H NMR spectra, it was confirmed that this was an acrylic group-containing organopolysiloxane represented by the following average composition formula (8). This had a viscosity of 460 cp and a refractive index of 1.417.

[0055]

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[0056]

[0057]

[0058]

[0059]

Example 2 The same hydrolyzable silane of the formula (5) as in Example 1 (29.
4 parts), octamethylcyclotetrasiloxane (100
Part 2) and Sample 2 in the same manner as in Example 1 except that an organosiloxane oligomer (2.4 parts) of the following formula (9) was used.
(112 parts) was obtained.

[0061]

Embedded image ((CH ₃ ) ₃ SiO _1/2 ) ₃ (CH ₃ Si
O _3/2 ) ₁ ... (9)

IR spectrum of sample 2, ²⁹ SiNM
From the analysis results of the R and ¹ H NMR spectra, it was confirmed that this was an acrylic group-containing organopolysiloxane represented by the following average composition formula (10). This had a viscosity of 370 cp and a refractive index of 1.416.

[0063]

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Next, samples 1 and 2 obtained in Examples 1 and 2
Was applied to polyethylene laminated paper using an offset transfer machine so that the coating amount was about 1.0 g / m ² ,
An electron beam was irradiated using an electron beam irradiator to cure the resin, and the curability and peelability at this time were examined. The results shown in Table 1 were obtained.

[0065]

[Table 1]

The samples 1 and 2 obtained in Examples 1 and 2
5% by weight of benzoyl isobutyl ether as a photoinitiator was added to the mixture, and this was applied to a polyethylene laminated paper using an offset printing machine so that the application amount was about 1.0 g / m ^2, and then air was added thereto. Two high-pressure mercury lamps (80 w / cm) were used in the inside, and cured by irradiating ultraviolet rays from a distance of 8 cm. The curability at this time and the peeling characteristics of the cured film were examined. The results were as follows.

[0067]

[Table 2]

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshio Ohba 1-10 Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory (56) References JP-A-4-353523 ( JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) C08G 77/20 C08G 77/06

Claims (3)

(57) [Claims] 1. A method comprising the steps of hydrolyzing a silane having an acrylic group or a methacryl group and a hydrolyzable group, and polymerizing the hydrolyzate together with diorganocyclosiloxane and a chain organosiloxane oligomer using an acid catalyst. A method for producing a (meth) acrylic group-containing organopolysiloxane, comprising: 2. After hydrolyzing a silane having an acryl group or a methacryl group and a hydrolyzable group in the coexistence of a diorganocyclosiloxane, the hydrolyzate is used together with a chain organosiloxane oligomer using an acid catalyst. A method for producing a (meth) acrylic group-containing organopolysiloxane, which comprises polymerizing. 3. The production method according to claim 1, wherein the chain organosiloxane oligomer has an acryl group or a methacryl group at a terminal.