JP3229394B2 - Method for producing diorganopolysiloxane containing diphenylsiloxy units capped with epoxy groups at both ends - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing a diorganopolysiloxane containing a diphenylsiloxy unit having both terminal epoxy groups blocked.

[0002]

2. Description of the Related Art Organopolysiloxanes having organic functional groups can impart the properties of organopolysiloxanes such as weather resistance, surface water repellency, lubricity, biocompatibility and gas permeability to organic resins. It is useful as a modifier for organic resins. Examples of such organopolysiloxanes having an organic functional group include various organic compounds such as amino-modified organopolysiloxane, epoxy-modified organopolysiloxane, methacryloxy-modified organopolysiloxane, carbinol-modified organopolysiloxane, and carboxylic acid-modified organopolysiloxane. Organopolysiloxanes having functional groups are known. Among these, epoxy-modified organopolysiloxane is used as a modifier for an epoxy resin for semiconductor encapsulation and is extremely useful. In addition, the properties of organopolysiloxane are improved by radiation resistance, heat resistance, nonflammability,
It is known that low-temperature flexibility, compatibility, moisture resistance, solder resistance, and marking properties are improved.

[0003]

The use of an epoxy-functional phenylpolysiloxane for modifying an epoxy resin can be expected to improve the above-mentioned properties, but it is difficult to produce a phenylpolysiloxane containing silicon-bonded hydrogen atoms as a raw material. It was difficult to produce epoxy group-containing phenylpolysiloxane. This is because when an acidic polymerization catalyst is used, a silicon atom-phenyl group bond is cleaved, and when a basic polymerization catalyst is used, a silicon atom-hydrogen atom bond is cleaved. The present inventor has previously proposed a method for producing an epoxy group-containing phenylpolysiloxane in Japanese Patent Application Nos. 3-185431 and 3-214735. However, the former method has a long manufacturing process leading to a final product, and has a difficulty in actually manufacturing in large quantities. The latter method has the drawback that an expensive and difficult to handle organolithium compound and expensive hexaphenylcyclotrisiloxane and hexamethylcyclotrisiloxane must be used. Also, a method of producing an epoxy group-containing organopolysiloxane in one step by an equilibrium polymerization method has been proposed (JP-A-3-255130,
JP-A-3-234768). However, these methods require the presence of an aprotic polar solvent that does not contain sulfur in the molecule, and these solvents usually have a high boiling point, so heat stripping after the polymerization reaction is completed at high temperature and high vacuum. This has the disadvantage that these polar solvents remain in the final polymer. Therefore,
There has been a demand for a method capable of easily producing an epoxy group-containing phenylpolysiloxane in a high yield in a short process. The present inventors have conducted intensive studies to solve the above problems,
The present invention has been reached. That is, an object of the present invention is to provide a method capable of producing a diorganopolysiloxane containing a diphenylsiloxy unit having both terminal epoxy groups blocked at both ends with high productivity.

[0004]

The present invention relates to (A) a diorganopolysiloxane containing diphenylsiloxy units and (B) a diorganosiloxane oligomer in which both ends of a molecular chain are blocked with an epoxy group-containing organic group. When,
The present invention relates to a method for producing a diorganopolysiloxane containing diphenylsiloxy units having both terminal epoxy groups blocked, wherein (C) dimethylpolysiloxane and (D) equilibrium polymerization in the presence of a basic catalyst.

The component (A) used in the present invention is a diorganopolysiloxane containing diphenylsiloxy units.
This component may contain a dimethylsiloxy unit as a structural unit in addition to the diphenylsiloxy unit. Specific examples of this component include cyclic diphenylpolysiloxanes such as hexaphenylcyclotrisiloxane and octaphenylcyclotetrasiloxane; 1,1-diphenyl-3,
3,5,5-tetramethylcyclotrisiloxane, 1,
Cyclic diphenylpolysiloxane / dimethylpolysiloxane copolymer such as 1,5,5-tetraphenyl-3,3,7,7-tetramethylcyclotetrasiloxane; dimethylpolysiloxane / diphenylpolysiloxane copolymer having both terminal hydroxyl groups blocked And chain polysiloxanes such as diphenylpolysiloxane having hydroxyl groups blocked at both ends. Also,
A hydrolyzate of diphenyldichlorosilane or a cohydrolyzate of diphenyldichlorosilane and dimethyldichlorosilane can also be used. When a hydrolyzate of a chain polysiloxane or dichlorosilane having hydroxyl groups blocked at both ends is used as this component, no silanol group remains in the final product, and no epoxy group is opened during polymerization. like,
Prior to the polymerization, it is necessary to condense the silanol group in the presence of a basic catalyst to be used and to remove generated water from the polymerization system by a conventionally known means such as azeotropic dehydration.

The component (B) used in the present invention is a diorganosiloxane oligomer in which both ends of the molecular chain are blocked by an epoxy group-containing organic group, and acts as a terminal blocking agent. The molecular weight of the target copolymer can be adjusted by the addition amount of this component. Specific examples of the epoxy group-containing organic group include γ-glycidoxypropyl group, γ-glycidoxybutyl group, γ-glycidoxyhexyl group, (3,4
-Epoxycyclohexyl) ethyl group,
Among them, a γ-glycidoxypropyl group is most preferable from the viewpoint of ease of production and economy. The substituent other than the epoxy group is most preferably a methyl group from the viewpoint of easiness of production and economy, but is not particularly limited as long as the substituent does not react with the basic catalyst used at the time of polymerization. This component can be easily produced by performing an addition reaction between a diorganopolysiloxane containing a silicon-bonded hydrogen atom and an organic compound containing an epoxy group and an aliphatic unsaturated group. As a specific example of this component, a dimethylsiloxane oligomer having a glycidoxypropyl group at both ends blocked such as 1,3-di (γ-glycidoxypropyl) tetramethyldisiloxane is exemplified.

The component (C) used in the present invention is dimethylpolysiloxane. By adjusting the addition amount of this component, the ratio of diphenylsiloxy units to dimethylsiloxy units in the target copolymer can be adjusted.
Specific examples of the component include cyclic dimethylpolysiloxanes such as hexamethylcyclotrisiloxane and octamethylcyclotetrasiloxane; and hydrolysates of dimethylpolysiloxane and dimethyldichlorosilane having both terminal hydroxyl groups blocked. When a hydrolyzate of dimethylpolysiloxane and dimethyldichlorosilane having hydroxyl groups blocked at both ends is used, the polymerization is carried out substantially in the absence of silanol groups and water in the same manner as in the case of the above-mentioned component (A). It is necessary.

The basic catalyst of the component (D) used in the present invention is an equilibrium polymerization catalyst, and specific examples thereof include lithium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, and tetramethylammonium hydroxide. Alkali silanolates such as lithium silanolate, sodium silanolate, potassium silanolate, cesium silanolate, and tetramethylammonium silanolate; butyllithium, phenyllithium, and the like;
Organic metal compounds such as methyllithium, sodium naphthalenide, potassium naphthalenide, and cumyl potassium are included. Among these, cesium and tetramethylammonium are preferable as the alkaline component in order to reach a complete equilibrium state during equilibrium polymerization.

[0009] The production method of the present invention comprises the above component (A),
The components (B), (C) and (D) are mixed and polymerized under appropriate polymerization conditions. The polymerization conditions are 50-
The reaction is preferably performed at a temperature of 200 ° C. for 5 minutes to 50 hours. Although it is the gist of the present invention that this reaction is carried out in the absence of a solvent, it may be carried out in the presence of a suitable solvent. Any solvent may be used as long as it is aprotic and well dissolves the starting material and the resulting polymer. Specific examples of the solvent include aliphatic hydrocarbons such as hexane and heptane, ethers such as tetrahydrofuran and diethyl ether, dimethylformamide, dimethylsulfoxide, and hexamethylphosphoric triamide. May be used in combination. For example, when using a low-polarity solvent such as toluene, it is recommended to add a high-polarity solvent such as dimethylformamide, dimethylsulfoxide, and hexamethylphosphoric triamide for the purpose of accelerating the reaction. . When a diorganopolysiloxane or a hydrolyzate of dichlorosilanes having both terminal hydroxyl groups is used as the component (A) or the component (C), a solvent such as toluene, benzene, or xylene which can be used for azeotropic dehydration is used. Aromatic hydrocarbon solvents are preferred. The polymerization reaction is usually followed by means such as a viscometer and gas chromatography, and after confirming that the state of equilibrium has been reached, the reaction is stopped by a neutralization operation. After deactivation of the equilibrium polymerization catalyst, the desired diorganopolysiloxane containing diphenylsiloxy units having both ends epoxy-blocked can be obtained by heating and distilling off the low-boiling substance and the solvent under reduced pressure.

The diorganopolysiloxane containing a diphenylsiloxy unit having an epoxy group blocked at both ends obtained by the production method of the present invention as described above improves, for example, the properties of epoxy resin such as moisture resistance, solder resistance, and printability. Is useful as a modifier for

[0011]

The present invention will be described below in detail with reference to examples.
In the examples, Me is a methyl group, Ph is a phenyl group, and Q is γ
-Represents a glycidoxypropyl group.

[0012]

Reference Example 1 Platinum and 1,2-divinyltetramethyl were added to 102.2 g (895.4 mmol) of allyl glycidyl ether charged in a four-necked flask equipped with a stirrer, a reflux tube, a thermometer, and a dropping funnel. When the complex with disiloxane has a platinum metal content of 15 p with respect to allyl glycidyl ether
pm. Then, the mixture was heated to 80 ° C, and 50 g (373.1 mmol) of 1,1,3,3-tetramethyldisiloxane was added dropwise while maintaining the temperature of the reaction mixture at 80 to 90 ° C. After dropping, 10
Stirred at 0 ° C for 0.5 hours. Infrared absorption spectrum analysis (hereinafter IR), gas chromatography (hereinafter GLC)
As a result, it was confirmed that the monoadduct of 1,1,3,3-tetramethyldisiloxane and allyl glycidyl ether had completely disappeared. Therefore, the reaction was terminated, and vacuum distillation was carried out at 166 to 167 ° C./1 mmHg. 113.9 grams of a fraction were obtained (84.2% yield). From the results of nuclear magnetic resonance analysis (hereinafter NMR), IR and quantitative determination of the epoxy group content, this reaction product was obtained from the disiloxane [1,3-bis (γ-glycidoxypropyl) -1] represented by the following chemical structural formula. ,
1,3,3-tetramethyldisiloxane]. The purity by GLC was 99.6%.

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[0013]

EXAMPLE 1 255.0 g of co-hydrolyzed product of diphenyldichlorosilane and dimethyldichlorosilane (64.1 mol% of diphenylsiloxy groups, 35.9 mol% of dimethylsiloxy groups) in a four-necked flask equipped with a stirrer, average Both ends hydroxyl-blocked dimethylpolysiloxane having a polymerization degree of 51.8 1
91.2 grams of a 50% by weight aqueous solution of cesium hydroxide in 0.2%.
31 g and 52.3 g of toluene were added, mixed and gradually heated, and water produced as a by-product was gradually removed from the system by distillation in order to maintain a reaction temperature of 150 ° C. Then, the mixture was cooled to 100 ° C., and 54.8 g (0.151 mol) of 1,3-bis (γ-glycidoxypropyl) -1,1,3,3-tetramethyldisiloxane synthesized in Reference Example 1 was added. Add 1
It heated and stirred at 40-150 degreeC for 4 hours. Thereafter, it was cooled to room temperature, 0.34 g (3.14 mmol) of trimethylchlorosilane was added, and the mixture was stirred for 0.5 hour to deactivate the catalyst. Then, distillation under reduced pressure was performed at 160 to 170 ° C./1 mmHg for 1 hour to remove toluene and low-boiling substances.
5.8 grams of polymer were obtained. The resulting polymer is
From the results of NMR, IR, gel permeation chromatography (hereinafter GPC) and quantitative determination of epoxy group content,
It was confirmed to be a diphenylsiloxane / dimethylsiloxane copolymer having both ends γ-glycidoxypropyl group blocked by the following average structural formula.

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[0014]

Example 2 In a four-necked flask equipped with a stirrer, 153.8 g of a co-hydrolyzed product of diphenyldichlorosilane and dimethyldichlorosilane (64.1 mol% of diphenylsiloxy groups, 35.9 mol% of dimethylsiloxy groups), average Hydroxyl-terminated dimethylpolysiloxane 3 having a polymerization degree of 51.8
36.1 g of a 50% by weight aqueous solution of cesium hydroxide in 0.1%.
33 g and 54.9 g of toluene were added and mixed and gradually heated, and water produced as a by-product was gradually removed from the system by distillation in order to maintain a reaction temperature of 150 ° C. Then, the mixture was cooled to 100 ° C., and 46.5 g (0.128 mol) of 1,3-bis (γ-glycidoxypropyl) -1,1,3,3-tetramethyldisiloxane synthesized in Reference Example 1 was added. Add 1
It heated and stirred at 40-150 degreeC for 4 hours. Thereafter, the mixture was cooled to room temperature, 0.24 g (2.2 mmol) of trimethylchlorosilane was added, and the mixture was stirred for 0.5 hour to deactivate the catalyst. Then, the mixture was distilled under reduced pressure at 160-170 ° C./1 mmHg for 1 hour to remove toluene and low-boiling substances.
6.5 grams of polymer were obtained. The resulting polymer is
From the results of NMR, IR, GPC, and quantification of the epoxy group content, it was confirmed that the copolymer was a diphenylsiloxane / dimethylsiloxane copolymer having both ends γ-glycidoxypropyl group and represented by the following average structural formula.

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[0015]

Example 3 In a four-necked flask equipped with a stirrer, 210.2 g (265.2 g of octaphenylcyclotetrasiloxane) was added.
0 mmol), octamethylcyclotetrasiloxane 2
35.1 g (792.6 mmol) and 0.15 g of cesium hydroxide were added, mixed and gradually heated to 150 ° C.
, And then cooled to 100 ° C. Then
54.8 g (0.151 mol) of 1,3-bis (γ-glycidoxypropyl) -1,1,3,3-tetramethyldisiloxane synthesized in Reference Example 1 was added, and 140-1
The mixture was heated and stirred at 50 ° C. for 4 hours. Thereafter, it was cooled to room temperature, 0.34 g (3.14 mmol) of trimethylchlorosilane was added, and the mixture was stirred for 0.5 hour to deactivate the catalyst. Then, distillation was performed under reduced pressure at 160-170 ° C./1 mmHg for 1 hour to obtain 465.8 g of a polymer excluding low-boiling substances. The obtained polymer was analyzed by NMR, IR, GP
From the results of quantification of the C and epoxy group contents, it was confirmed that the copolymer was a diphenylsiloxane / dimethylsiloxane copolymer having both ends γ-glycidoxypropyl group and represented by the following average structural formula.

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[0016]

According to the production method of the present invention, it is possible to produce a diorganopolysiloxane containing diphenylsiloxy units having both terminal epoxy groups blocked in a high yield in a short process.

(56) References JP-A-5-9296 (JP, A) JP-A-5-32783 (JP, A) JP-A-3-255130 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) C08G 77/06-77/10 C08G 77/38

Claims (1)

(57) [Claims] 1. A method comprising: (A) a diorganopolysiloxane containing diphenylsiloxy units, (B) a diorganosiloxane oligomer in which both molecular chain terminals are blocked with an epoxy group-containing organic group, and (C) dimethylpolysiloxane. (D)
A method for producing a diorganopolysiloxane containing diphenylsiloxy units having both terminal epoxy groups blocked, wherein equilibrium polymerization is carried out in the presence of a basic catalyst.