JPH0587087B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for producing an epoxy group-containing organopolysiloxane, and in particular to a method for producing an epoxy group-containing organopolysiloxane that can be produced by a simple operation without cleavage of the epoxy group during the reaction. The present invention relates to a method for manufacturing. (Prior technology) Epoxy group-containing organosiloxanes are used in many applications such as fiber treatment agents, water repellents, and resin modifiers, and those with a relatively high degree of polymerization have a moderate degree of flexibility. It is considered to be an excellent fiber treatment agent because it does not cause excessive sliminess or yellowing unlike aminosiloxanes. Various methods are already known for producing this epoxy group-containing organosiloxane, including a method in which an olefin group-containing siloxane is subjected to a peroxidation reaction, such as a method in which vinyl siloxane is subjected to a peroxidation reaction with a 40% peracetic acid solution. A method of oxidizing, a method of epoxidizing a Grignardized siloxane such as the formula ≡SiCH ₂ MgBr with alkali treatment with epichlorohydrin, a method of reacting a chlorosilane or acetoxysilane compound with glycidol to produce glycidyl silicone ether. (see US Pat. No. 2,730,532), but all of these methods have the drawbacks of low yield, complicated operations, and poor stability. This method epoxidizes silane or low-molecular siloxane, and as a method for epoxidizing high-molecular polysiloxane, it has the disadvantage that it is difficult to put into practical use industrially because there are various restrictions on reaction conditions. Therefore, in the production of this type of epoxidized organopolysiloxane, an addition reaction is carried out between an unsaturated epoxy monomer and an organohydrodiene polysiloxane containing a hydrogen atom bonded to a silicon atom using a peroxide or a platinum-based catalyst. A method has also been proposed (US Pat. No. 3,431,143).
Although this method is easy to operate and has a high reaction rate, it is difficult to control the reaction when obtaining a product with a relatively high degree of polymerization. Hydrodiene polysiloxanes are difficult to produce, and the production flow is complicated and time-consuming, resulting in high costs. On the other hand, when producing organosiloxanes from low-molecular organosiloxanes such as cyclic siloxanes, acids,
A method of equilibration reaction using a base as a catalyst is known, but since acid catalysts easily react with epoxy groups, this method cannot be used for equilibration of epoxy group-containing siloxanes, and a basic catalyst is used. In this case, equilibration with the epoxy group-containing siloxane is extremely slow and there is a problem in the cleavage of the epoxy group. (Problem to be Solved by the Invention) It is known that the equilibration of organopolysiloxane is promoted by adding a small amount of a specific polar solvent. is also known, but it has the disadvantage of not being put to practical use because it is affected by extremely small amounts of impurities such as water. Regarding the production of organopolysiloxane using a basic catalyst, a method has been proposed in which the reaction rate is accelerated by adding an alkyl sulfone or alkyl sulfoxide such as dimethyl sulfoxide (see US Pat. No. 3,175,995). This is because the yield of organopolysiloxane decreases due to cleavage of the epoxy ring, and because these organic solvents have high melting points, even dimethyl sulfoxide, which has the lowest melting point, remains solid in winter, making it difficult to handle. Also, because of their high boiling points, they are difficult to separate after the reaction, leaving a characteristic odor, and furthermore, when used in combination with other resins when using this siloxane for textile treatment, it may cause discoloration. or
This has the disadvantage of decreasing the stability of the processing solution. In addition, if this is equilibrated using a basic catalyst in a state containing no more than 1% by weight of saturated water, a relatively low-molecular-weight epoxy group-containing siloxane can be obtained without cleavage of the oxirane ring. The method is also known (see Japanese Patent Publication No. 51-33839), and although this method improves the equilibration rate, it cannot avoid the cleavage of the oxirane ring by water, and due to the presence of water, During the equilibration reaction, silanol groups are generated at the ends of the siloxane, stopping the growth of the siloxane chain, making polymerization difficult. Furthermore, the product has a large variation in the degree of polymerization, making it difficult to reproduce the production process. (Means for Solving the Problems) The present invention relates to a method for producing an organopolysiloxane containing an epoxy group that solves the above-mentioned disadvantages. 100 parts by weight of a mixture with an organosiloxane containing no
b) 1 to 50 parts by weight of an aprotic polar organic solvent that does not contain sulfur in the molecule, c) Basic equilibration catalyst
A mixture consisting of 0.001 to 1 part by weight is heated and reacted to form the general formula

[Formula] (where R ¹ is a monovalent organic group containing an epoxy group,
R ² is 1 with 1 to 8 carbon atoms that does not contain an epoxy group
Contains an average of one or more epoxy groups in a molecule represented by a valent hydrocarbon group or an alkoxy group having 1 to 3 carbon atoms, where m and n are numbers satisfying 1.8<m+n<2.1 with n/m≧3. It is characterized by obtaining organopolysiloxane. That is, as a result of various studies conducted by the present inventors on methods for equilibration reaction of organopolysiloxanes containing epoxy groups in the presence of a basic catalyst, a mixture of siloxanes containing epoxy groups and siloxanes not containing epoxidation was found. If an aprotic organic solvent that does not contain sulfur in its molecules is added to the equilibration reaction system in the presence of a basic equilibration catalyst, the reaction can proceed with a relatively low viscosity. Since this equilibration reaction can be accelerated, it can be carried out in a short time, and the desired epoxy group-containing organopolysiloxane can be obtained with a high degree of polymerization. They discovered that the polymerization of siloxane can be controlled as specified, and completed the present invention by conducting research on the types and amounts of each component to be used. (Function) The present invention comprises a) a mixture of an epoxy group-containing organopolysiloxane and an epoxy group-free organosiloxane, b) an aprotic organic solvent that does not contain sulfur in its molecules, and c) a basic equilibration catalyst. The present invention relates to a method for producing an epoxy group-containing organopolysiloxane by mixing them and subjecting them to a heating reaction. The organosiloxane used as the starting material in the present invention is a mixture of a siloxane containing an epoxy group and an organosiloxane not containing an epoxy group, and both of these siloxanes preferably have a degree of polymerization because they are advantageous in operation. 100
The following are used, but these may be any of cyclic siloxanes, disiloxanes, and linear siloxanes. Organosiloxane containing this epoxy group has the general formula

[Chemical formula], and R ³ is an alkyl group such as a methyl group, propyl group, butyl group, an aryl group such as a phenyl group or tolyl group, or a part of the hydrogen atom bonded to a carbon atom in these groups. or chloromethyl group, trifluoropropyl group, completely substituted with halogen group, cyano atom, mercapto group, etc.
1 to 20 carbon atoms selected from cyanoethyl groups, etc.
The same or different unsubstituted or substituted monovalent hydrocarbon groups excluding alkenyl groups, A is an epoxy group-containing organic group, a is 0 or a positive integer, b is a positive integer, a cyclic siloxane, or a general formula

It is a chain siloxane represented by the following formula, where R ₃ and A are the same as above, c is 0 or 1, and d and e are 0 or a positive integer. The epoxy group-containing organic group represented by A above is, for example,

【formula】

【formula】

[ka]

[Formula] It is said to be a group shown by the formula, and this epoxy group-containing organosiloxane has the formula

[ka]

[ka]

[ka]

[ka] A cyclic siloxane with the formula

[ka]

[ka]

An example is a linear siloxane represented by the following formula. In addition, the organosiloxane that does not contain epoxy groups used here may be a conventionally well-known organosiloxane, which has the formula

[ka]

[ka]

Examples are those shown by [C]. Such low molecular weight organosiloxanes can be obtained by hydrolysis and condensation polymerization of one or a mixture of the corresponding chlorosilanes and alkoxysilanes. The epoxy group may be introduced into the siloxane by a known method. This epoxy group can be introduced by, for example, 1) epoxidizing an olefin-containing silane or siloxane using a peroxidation reaction, 2) treating a Grignard-containing silane with an alkali such as epichlorohydrin, or 3) converting a chlorosilane or acetoxysilane compound to glycidol. 4) Addition reaction of unsaturated epoxy monomers using a platinum catalyst may be used.
Method 4) is preferable because it is easy to operate, has a high reaction rate, and produces a water-resistant epoxy group-containing organosiloxane with silicon-carbon bonds. Since the amount of epoxy monomer required is less than 20% by weight excess of the amount required for complete reaction with the organohydrodiene polysiloxane, side reactions or polymerization reactions due to unreacted epoxy monomer can be avoided. It gives you the advantage of being able to do it. Note that component (a) in the present invention is a mixture of the above-mentioned epoxy group-containing organosiloxane and an epoxy group-free organosiloxane, and the blending ratio of both is such that it is contained in the target organopolysiloxane. It may be set arbitrarily depending on the amount of epoxy groups to be used. Next, the organic solvent as component (b) used in the present invention is an aprotic polar organic solvent that does not contain sulfur in its molecules. This organic solvent has a large dielectric constant ε and is characterized by not having proton-donating groups, but it is generally highly associative and has a large ability to transform protons, so it is often used as a solvent for organic ion reactions. , which disassociate from self-association and create a more stable solvation state, exhibiting significant interactions with ionic reactive species. Examples of the aprotic polar solvent include N,N-dimethylformamide, N,N-dimethylacetamide, tetramethylurea, acetonitrile, propylene carbonate, nitrobenzene, nitromethane, dimethylcyanamide, tetrahydrofuran, dioxane, and pyridine. Among these, they are liquid at room temperature, making them easy to handle, such as measuring, compounding, and transferring.They also have a moderate boiling point, making them convenient for controlling reactions, and after the reaction is completed, they can be easily removed from the system by heating and reducing pressure. N,
Particularly preferred is N-dimethylformamide. If the amount of this organic solvent added is less than 1 part by weight per 100 parts by weight of the organosiloxane as component (a), the desired equilibration reaction will be delayed and the sufficient effect of the present invention may not be obtained. figure,
If the amount exceeds 50 parts by weight, the amount of cyclic substances produced increases and it becomes difficult to control the desired degree of polymerization, so it is necessary to keep it in the range of 1 to 50 parts by weight, but this preferred range The amount is 5 to 40 parts by weight. Furthermore, the basic equilibration catalyst used in the present invention as component c) is a catalyst for carrying out an alkaline equilibration reaction of the organosiloxane as component a) described above, and includes potassium hydroxide. , alkali metal hydroxides such as sodium hydroxide, cesium hydroxide, alkali metal silanolates such as potassium salt of methyltrihydroxysilane, potassium salt of phenyltrihydroxysilane, etc., octamethylcyclotetrasiloxane and potassium hydroxide. potassium silanolate, quaternary ammonium salts such as benzyltrimethylammonium hydroxide, tetramethylammonium hydroxide, trimethylammonium hydroxide, octyltrimethylammonium hydroxide, etc., or compounds with the general formula R ⁴ ₄ POR ⁵ (R ⁴ is 1
valent organic group, R ⁵ is a hydrogen atom or a monovalent organic group)
Phosphonium salts represented by, for example, tetramethylphosphonium hydroxide, tetra-n-
Butylphosphonium hydroxide, phenyltrimethylphosphonium hydroxide,
Examples include tetramethylphosphonium methoxide, tetrabutylphosnium butoxide, butyltricyclohexylphosphonium hydroxide, and among these, potassium hydroxide, potassium silanolate, and phosphonium bases are preferred. Particularly preferred is tetra-n-butylphosphonium hydroxide, which is decomposed by heating to remove the organic solvent, thereby eliminating the need for a neutralization salt removal step. Note that the amount of this base equilibrating catalyst added is the same as that of the organosiloxane mixture as component (a) above.
If it is less than 0.001 part by weight per 100 parts by weight, the equilibration reaction of organosiloxane will be slow, and if it is more than 1 part by weight, no further effect will be obtained.
The amount may be in the range of 0.001 to 1 part by weight, and the preferred range is 0.1 to 0.5 part by weight. The organopolysiloxane according to the present invention is produced using the above-mentioned a) mixture of an epoxy group-containing organosiloxane and an epoxy group-free organosiloxane as a component, b) an aprotic polar organic solvent as a component, and c) a component as an aprotic polar organic solvent. After uniformly mixing a predetermined amount of the basic equilibration catalyst, the alkaline equilibration reaction may be carried out by heating, but this heating is performed at a temperature of 60°C or more and 240°C or less, preferably 80 to 180°C. According to this, since the aprotic polar organic solvent as component (b) is present, the alkaline equilibration reaction of the organosiloxane proceeds in a very short time, and during this reaction, the epoxy ring is cleaved. Equilibration of the epoxy group-containing organosiloxane proceeds smoothly, and an epoxy group-containing organopolysiloxane can be easily obtained, and the viscosity of this organopolysiloxane can also be freely controlled. Therefore, it is industrially useful in that an organopolysiloxane containing an epoxy group can be advantageously obtained. (Example) Next, a synthesis example of an epoxy group-containing organosiloxane used in the present invention and an example of the present invention,
A comparative example is given, and the viscosity, specific gravity, and refractive index in the example are measured values at 25°C. Synthesis Example 1 855 g of allyl glycidyl ether, 855 g of toluene, and 0.6 g of chloroplatinic acid olefin complex salt containing 2% by weight of platinum were charged into a four-necked flask equipped with a dropping funnel, a reflux device, and a thermometer.
After heating under reflux for dehydration at 110°C for 30 minutes, the temperature was maintained at 90°C, and a mixture of 405 g of 1,2,3,4-tetramethylcyclotetrasiloxane and 405 g of toluene was added dropwise from the dropping funnel over 2 hours, during which time the temperature teeth
The temperature was maintained at 90°C, and after the completion of the dropwise addition, the mixture was further reacted at 90°C for 5 hours, and then cooled to below 30°C.
The reaction rate was determined by treating unreacted =SiH with a 20% caustic potassium aqueous solution and measuring the amount of hydrogen gas generated, which was 98.7%. Next, this reaction solution was neutralized by washing with water three times, and then heated at 100°C for 3 hours under a reduced pressure of 10 mmHg to strip off the solvent and unreacted substances. Compound 1 was obtained. The material has a viscosity of 110cS, a specific gravity of 1.117, a refractive index of 1.4623, and an epoxy value of 0.574 mol/
The physical properties of 100g are shown, and the structural formula of this substance is IR,
After examining it with NMR, this formula is

[Formula] It was confirmed that the following is true. Synthesis Example 2 2 with dropping funnel, reflux device and thermometer installed
allyl glycidyl ether in a four-necked flask.
92.9g, heptamethylcyclotetrasiloxane
Prepare 207.1g and 300g of toluene and heat at 110℃.
After dehydration under heating under reflux for 30 minutes, 0.15 g of chloroplatinic acid olefin complex salt containing 2% by weight of platinum was added and reacted at 85°C for 5 hours. After the reaction was completed, the amount of hydrogen gas was measured using a 20% caustic potassium aqueous solution. The rate was 100%. Next, the reaction solution was cooled, washed with water three times to neutralize it, and then stripped at 80°C for 3 hours under a reduced pressure of 10 mmHg to obtain Compound 2, which had a viscosity of 33 cS, a specific gravity of 1.028, It exhibits physical properties with a refractive index of 1.4254 and an epoxy value of 0.252 mol/100g, and when the structural formula of this substance was examined by IR and NMR, it was found to be of the formula

It was confirmed that it is shown by [Formula]. Synthesis Example 3 Into the same four-necked flask as in Synthesis Example 2, 156.8 g of allyl glycidyl ether, 156.5 g of toluene, and 0.5 g of the same chloroplatinic acid olefin complex salt as in Synthesis Example 1 were charged, and after dehydration under reflux at 110°C for 30 minutes,
While maintaining the temperature at 90°C, a mixed solution of 406.2 g of 1,2,3,4-tetramethyl-1,2,3-tripropylcyclotetrasiloxane and 406.2 g of toluene was added dropwise from the dropping funnel over 2 hours. 6 at 95℃
The reaction was continued for a period of time, and when the amount of hydrogen gas was measured after the reaction was completed, the reaction rate was 89.4%. Next, this reaction solution was cooled, washed with water three times to neutralize it, and then stripped at 100°C for 3 hours under a reduced pressure of 10 mmHg to obtain Compound 3, which had a viscosity of 11 cS and a specific gravity of 0.994. , refractive index 1.4347,
It exhibits physical properties with an epoxy value of 0.208 mol/100g, and when the structural formula of this product was investigated by IR and NMR, it was found that the formula

It was confirmed that it is shown by [Formula]. Synthesis Example 4 Allyl glycidyl ether in Synthesis Example 1
When the same procedure as in Synthesis Example 1 was carried out except that 930 g of vinylcyclohexene epoxide and 930 g of toluene were used instead of 855 g of vinylcyclohexene epoxide and 855 g of toluene, compound-4 was obtained with a reaction rate of 97.4%, and this product had a volatile content of 1.2. It shows physical properties with an epoxy value of 0.544 mol/100g in %, and the structural formula examined by IR and NMR is the formula

It was confirmed that it is shown by [Formula]. Synthesis Example 5 405g of 1,2,3,4-tetramethylcyclotetrasiloxane and 405g of toluene in Synthesis Example 1
Instead of the average expression

Methylhydrodiene polysiloxane represented by
When the reaction was carried out in the same manner as in Synthesis Example 1 except that 909 g of toluene and 909 g of toluene were used, the reaction rate was 96.4.
%, compound-5 was obtained, which had a volatile content (105℃ x 3 hours) of 0.8%, a viscosity of 580cS, and an epoxy value.
It showed a physical property of 0.402 mol/100g, and when the structural formula of this substance was investigated by IR and NMR, it was found to be the formula

It was confirmed that it was as shown in [C]. Example 1 In a four-necked flask equipped with a stirrer, a thermometer, and a nitrogen gas inlet, 659 g of octamethylcyclotetrasiloxane, 17.4 g of the compound-1 prepared in Synthesis Example 1, and a trimethylsilyl group at the end of the molecular chain were added. 74.1 g of dimethylpolysiloxane with an average degree of polymerization of 100 and 75 g of N,N-dimethylformamide were charged and dehydrated under reflux at 110°C for 30 minutes, followed by (nC ₄ H ₉ ) ₄ as a basic catalyst. Add 2.5g of POH dropwise and add 110g while stirring.
The equilibration reaction was carried out at ℃ for 5 hours. After the reaction was completed, the mixture was heated at 140°C for 1 hour to decompose (nC ₄ H ₉ ) ₄ POH as a catalyst, and then cooled.
After treatment with activated carbon and filtration, the obtained product was
Compound-A was obtained by heating at 120° C. for 2 hours under a reduced pressure of mmHg to strip off the solvent and unreacted substances. This substance is a pale yellow transparent liquid with volatile content (105℃
x 3 hours) 1.2%, viscosity 840p, refractive index 1.4046,
The epoxy value was 0.013 mol/100g, which matched the value set from the initial charging ratio. When this product was subjected to GPC, it showed a single peak, the molecular weight was 75,000 (degree of polymerization approximately 1,000), and IP and NMR confirmed that it had the following structural formula.

[Chemical Formula] Examples 2 to 4 Instead of 659 g of octamethylcyclotetrasiloxane and 17.4 g of Synthesis-1 in Example 1,
Example 1 except that octamethylcyclotetrasiloxane and compounds 2 to 4 were used in the amounts shown in Table 1.
Compounds B, C, and D were prepared in the same manner as above, and these compounds exhibited the physical properties shown in Table 2.

【table】

【table】

[Table] Example 5 The raw materials used in Example 1 were 724 g of octamethyltetracyclosiloxane, 24.9 g of compound-5, 1.18 g of octamethyltrisiloxane, 45 g of N,N-dimethylformamide, and (nC ₄ H ₉ ) ₄ OH1. Compound E was treated in the same manner as in Example 1 except that the amount was 5 g.
The result was a pale yellow transparent liquid with a volatile content of 1.2% (105°C x 3 hours), a viscosity of 830p, and an epoxy value of 0.012 mol/100g, and the GPC results showed a single peak with an average molecular weight of 75,000, an average degree of polymerization of about 1,000, no odor, and a methoxy value of 0. Examples 6-8 Dimethylpolysiloxane 74.1 in Example 1
When treated in the same manner as in Example 1 except that the organopolysiloxane shown in Table 3 was used instead of g, the corresponding compounds F, G, and H were obtained, which were as shown in Table 4. The physical properties were shown.

【table】

【table】

[Table] Comparative Examples 1 to 5 Instead of 75 g of N,N-dimethylformamide in Example 1, no solvent was used at all, or
Example 1 except that the solvents shown in the table were used.
When compounds were prepared in the same manner as above, compounds with the physical properties shown in Table 5 were obtained, but in this case, a reduction in the amount of epoxy groups was observed in each compound, making it the desired compound. There were some cases in which no material with physical properties could be obtained, some in which raw material peaks remained because equilibration did not proceed, some cases in which the peak position was unclear due to a clear overall broad spectrum, and 2 points in which the molecular weight could be confirmed by GPC. It was nothing more than a simple thing.

【table】

[Table] Examples 9-10, Comparative Examples 6-7 Instead of 75 g of N,N-dimethylformamide in Example 1, 22.5 g of N,N-dimethylformamide (Example 9), 500 g (Example 10) ,
Compounds were produced in the same manner as in Example 1, except that 3.75 g (Comparative Example 6) and 750 g (Comparative Example 7) were used. Compounds having the physical properties shown in Table 6 were obtained.

【table】

[Table] Examples 11 to 13, Comparative Example 8 A four-necked flask (No. 3) equipped with a dropping funnel, a reflux device, and a thermometer was charged with the types and amounts of raw materials shown in Table 7, and the same procedure as in Example 1 was carried out. When the compound was synthesized under the following conditions, the degree of polymerization was set at 200, the results shown in Table 7 were obtained for the resulting compound.

【table】

[Table] ｜ / ＼
C ₃ H ₆ OCH ₂ CH −
_CH2
(Effects of the Invention) The present invention relates to a method for producing an organopolysiloxane containing an epoxy group, and as described above, this includes (a) a mixture of an organosiloxane containing an epoxy group and a siloxane containing no epoxy group, and b) According to this method, an organopolysiloxane containing an epoxy group is produced by equilibrating a composition consisting of an aprotic polar organic solvent that does not contain sulfur in the molecule and c) a basic equilibration catalyst. Since an aprotic polar organic solvent is added to this system, 1) the equilibration reaction is carried out in a short time, 2) epoxy ring cleavage does not occur during the equilibration reaction, and 3) the target organopolysiloxane is produced. Since the degree of polymerization can be controlled as desired, it is industrially advantageous in that organopolysiloxanes containing epoxy groups can be easily obtained.

Claims (1)

[Scope of Claims] 1 a) 100 parts by weight of a mixture of an organosiloxane containing an epoxy group and an organosiloxane not containing an epoxy group, b) 1 to 50 parts by weight of an aprotic organic solvent that does not contain sulfur in its molecule. , c) 0.001 to 1 part by weight of a basic equilibration catalyst, and a mixture of the following is heated and reacted to form a compound of the general formula [Formula] (where R ¹ is an epoxy group-containing monovalent organic group,
R ² is 1 with 1 to 8 carbon atoms that does not contain an epoxy group
Contains an average of one or more epoxy groups in a molecule represented by a valent hydrocarbon group or an alkoxy group having 1 to 3 carbon atoms, where n and m are numbers satisfying 1.8<m+n<2.1 with n/m≧3. A method for producing an epoxy group-containing organopolysiloxane, the method comprising obtaining an organopolysiloxane.