JP2010174081A - Method for producing terminal hydrocarbyloxy group-containing diorganopolysiloxane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently producing a terminal hydrocarbyloxy group-containing diorganopolysiloxane in a short time by a comparatively small installation, and to provide a method for continuously producing the diorganopolysiloxane. <P>SOLUTION: The method for producing the terminal hydrocarbyloxy group-containing diorganopolysiloxane having a specific structure includes mixing a reaction liquid containing (A) a diorganopolysiloxane having an alkenyl group, (B) a hydrosilyl group-containing hydrocarbyloxysilane represented by general formula (1): (R<SP>1</SP>O)<SB>a</SB>R<SP>2</SP><SB>3-a</SB>-Si-H (wherein, R<SP>1</SP>s are each independently 1-8C nonsubstituted or alkoxy-substituted monovalent hydrocarbon; R<SP>2</SP>is 1-13C monovalent hydrocarbon; and (a) is an integer of 1-3), and (C) a platinum group metal-based catalyst in a tube reactor by reciprocally vibrating the reaction liquid in the axis direction of the tube reactor, and reacting the components (A) with (B) in the presence of the component (C). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a process for producing a terminal hydrocarbyloxy group-containing diorganopolysiloxane useful as a base polymer of a one-component dealcohol-free RTV (room temperature curable) organopolysiloxane composition.

  A one-component dealcohol-free RTV organopolysiloxane composition basically composed of a base polymer composed of a silanol-terminated diorganopolysiloxane polymer and a crosslinking agent composed of an alkoxy-functional silane / siloxane is not corrosive and has little odor Has the advantage. However, it is very difficult to remove from the composition the alcohol produced by the reaction of the silanol group at the polymer end with the alkoxy functional crosslinking agent during the preparation, and the alcohol remaining in the composition in this way. There is a problem that the storage stability of the composition is lowered.

  In order to solve this problem, it is effective to use a base polymer obtained by reacting a terminal silanol group of a silanol-terminated diorganopolysiloxane polymer with an alkoxy functional crosslinking agent in advance. Patent Document 1 discloses a composition comprising a terminal alkoxy group-containing base polymer having a silalkylene skeleton, and Patent Document 2 discloses a composition comprising a terminal alkoxy group-containing base polymer having a siloxane skeleton. Patent Document 3 discloses a composition comprising a terminal alkoxysilyl-blocked organopolysiloxane, an alkoxysilane, and an alkoxytitanium. Further, Patent Document 4 discloses that an alkoxy functional crosslinking agent having a hydrogen atom bonded to silicon and a terminal silanol group of a silanol-terminated diorganopolysiloxane polymer is reacted in advance. In addition, Patent Document 5 discloses a composition comprising a terminal alkoxysilyl group-blocked organopolysiloxane containing a silethylene group, an alkoxysilane, and an alkoxytitanium. By the way, in order to industrially prepare a siloxane having a terminal alkoxy-modified in advance, it is important to complete the reaction at a relatively low temperature in a short time from the viewpoint of productivity and cost. However, the reaction between the terminal silanol group and the alkoxy functional crosslinking agent disclosed in Patent Documents 1 to 5 requires a long process at a relatively high temperature.

  As shown in Example 4 of Patent Document 6 and Reference Example 1 of Patent Document 5 described above, a platinum catalyst is required when a hydrosilyl group-containing alkoxysilane is added to a terminal vinyl group-blocked organopolysiloxane. From the viewpoint of saving resources and the high cost of the catalyst itself, only a small amount of platinum catalyst is added to the terminal vinyl group-blocked organopolysiloxane. Therefore, when the viscosity of the organopolysiloxane is increased, there arises a problem that it takes a long time to uniformly mix this small amount of platinum catalyst in order to sufficiently proceed the reaction. Further, in Patent Document 6 mentioned above, it is stated that the reaction temperature is raised as a method for increasing the reaction rate. However, as the reaction apparatus becomes larger, the time required for temperature rise and cooling becomes longer. Since a device for temperature and cooling is newly required, there arises a problem that the installation place of the entire device must be widened.

  As a continuous production method of a terminal hydrolyzable group-capped organopolysiloxane, Patent Document 7 discloses a method using a mixing device provided with a reciprocating agitator, and Patent Document 8 has a dynamic mixing function. A method using no tubular reactor is disclosed. In these methods, since a condensation reaction between the terminal silanol group and the alkoxysilane is used, after performing the condensation reaction with these apparatuses, an evaporation operation for removing volatile components such as by-produced alcohol is performed. Necessary.

U.S. Pat. No. 3,175,993 US Pat. No. 3,161,614 Japanese Patent Laid-Open No. 55-43119 Japanese Patent Publication No. 3-8657 Japanese Examined Patent Publication No. 7-39547 Japanese Unexamined Patent Publication No. 59-131431 JP 2001-114896 A JP 2003-246860 A

  The present invention has been made in view of the above circumstances, and compared terminal hydrocarbyloxy group-containing diorganopolysiloxane, which is a base polymer of a one-component dealcohol-free RTV organopolysiloxane composition that occupies an important position in the silicone industry. An object of the present invention is to provide a method for efficiently producing in a short time by a small-scale facility. It is another object of the present invention to provide a method for continuously producing a terminal hydrocarbyloxy group-containing diorganopolysiloxane.

  As a result of intensive studies, the present inventors have found that the above-mentioned problems can be solved by mixing the raw materials in the tubular reactor by reciprocating vibration along the axial direction thereof, and the present invention has been made. It was.

That is, the present invention
(A) a diorganopolysiloxane having an alkenyl group,
(B) The following general formula (1):
(R ¹ O) _a R ² _3-a -Si-H (1)
Wherein R ¹ is independently an unsubstituted or alkoxy group-substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, R ² is a monovalent hydrocarbon group having 1 to 13 carbon atoms, and a is (It is an integer from 1 to 3.)
(C) A reaction solution containing a hydrocarbyloxysilane containing a hydrosilyl group and a platinum group metal catalyst is mixed in a tubular reactor by reciprocating vibration along the axial direction of the tubular reactor, A) component and (B) component are reacted in the presence of component (C), the following general formula:
(R ¹ O) _a R ² _3-a -Si-A-
(Wherein R ¹ , R ² and a are as defined above, and A is an alkylene group.)
The manufacturing method of the terminal hydrocarbyloxy group containing diorganopolysiloxane which has a structure represented by these is provided. The terminal hydrocarbyloxy group refers to a group represented by the formula: R ¹ O in the structure represented by the above general formula.

  By the production method of the present invention, a terminal hydrocarbyloxy group-containing diorganopolysiloxane can be efficiently produced in a short time. Moreover, the terminal hydrocarbyloxy group containing diorganopolysiloxane can also be continuously manufactured by the manufacturing method of this invention. In the method of the present invention, an alkenyl group present in diorganopolysiloxane and a hydrosilyl group-containing hydrocarbyloxysilane are addition-reacted with a platinum catalyst. Except for the case where a solvent is added to lower the viscosity, an evaporation operation is unnecessary, and thus the manufacturing process is simple.

It is the schematic which shows an example of the manufacturing system containing the tubular reactor used by this invention. It is the schematic which shows another example of the manufacturing system containing the tubular reactor used by this invention.

  Hereinafter, the present invention will be described in more detail. In the present specification, the viscosity is a value measured with a rotational viscometer, and ppm is based on mass.

[(A) component]
The component (A) is a diorganopolysiloxane having an alkenyl group and forms the basic skeleton of a terminal hydrocarbyloxy group-containing diorganopolysiloxane. As an alkenyl group, C2-C6 alkenyl groups, such as a vinyl group and an allyl group, are mentioned, for example. (A) A component may be used individually by 1 type, or may use 2 or more types together.

  (A) The preferable viscosity of a component is 100-1,000,000 mPa * s in 25 degreeC. If the viscosity is 1,000,000 mPa · s or less, there is no particular need for measures against friction pressure when mixing by reciprocating vibration in a tubular reactor, so the equipment is simpler and more cost effective. It is hard to be disadvantageous.

As a preferable example of the component (A), the following general formula (2):
X _b -R ³ _3-b SiO (R ⁴ ₂ SiO) _n (X _2-c R ⁴ _c SiO) _m SiR ³ _{3-b '} -X _b' (2)
(Wherein R ³ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 6 carbon atoms other than an alkenyl group, and R ⁴ is independently an unsubstituted or substituted carbon atom having 1 to 13 carbon atoms. X is an alkenyl group having 2 to 6 carbon atoms, b and b 'are integers of 0 to 3, c is 0 or 1, and m is 0 to 10 (It is an integer, n is an integer of 10 or more, provided that b + b ′ + m (2-c) is an integer of 1 or more.)
The diorganopolysiloxane represented by these is mentioned.

Specific examples of R ³ include alkyl groups having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, and a hexyl group; a cycloalkyl group such as a cyclopentyl group and a cyclohexyl group; An unsubstituted monovalent hydrocarbon group, and at least a part of hydrogen atoms of these monovalent hydrocarbon groups are substituted with a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom) or the like, for example, chloro Examples thereof include substituted monovalent hydrocarbon groups such as a halogen-substituted monovalent hydrocarbon group such as a methyl group and a 3,3,3-trifluoropropyl group. R ³ may be the same as or different from each other. R ³ is preferably a methyl group or a phenyl group, and more preferably a methyl group.

R ⁴ is preferably other than an alkenyl group. Specific examples of R ⁴ include alkyl groups having 1 to 13 carbon atoms such as methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, decyl group and tridecyl group; cyclopentyl group, cyclohexyl group and the like. An aryl group having 6 to 13 carbon atoms such as phenyl group, tolyl group and naphthyl group; unsubstituted aralkyl group having 7 to 13 carbon atoms such as benzyl group, phenylethyl group and phenylpropyl group And at least part of the hydrogen atoms of these monovalent hydrocarbon groups are substituted with halogen atoms (fluorine atoms, chlorine atoms, bromine atoms, iodine atoms), cyano groups, etc. Chloromethyl group, trifluoromethyl group, chloropropyl group, 3,3,3-trifluoropropyl group, chlorophenyl group, dibromophenyl group, Examples include halogen-substituted monovalent hydrocarbon groups such as tetrachlorophenyl group and difluorophenyl group; substituted monovalent hydrocarbon groups such as cyanoalkyl groups such as β-cyanoethyl group, γ-cyanopropyl group, and β-cyanopropyl group. . R ⁴ may be the same as or different from each other. R ⁴ is preferably a methyl group or a phenyl group, and more preferably a methyl group.

  Specific examples of X include alkenyl groups having 2 to 6 carbon atoms such as vinyl group and allyl group. X may be the same or different from each other. X is preferably a vinyl group.

  As described above, b and b ′ are integers of 0 to 3, and c is 0 or 1. The n is an integer of 10 or more, preferably an integer of 20 to 10,000. m is an integer of 0 to 10, preferably an integer of 0 to 5. Further, b, b ′, c, and m are not limited in use as long as b + b ′ + m (2−c) is an integer of 1 or more, but b = b ′ = 1 and m = 0. (That is, the diorganopolysiloxane represented by the general formula (2) has one to two alkenyl groups having 2 to 6 carbon atoms at both ends and constitutes the diorganopolysiloxane. Or b = b ′ = 1, c = 1 and 1 ≦ m ≦ 10 (that is, the diorganopolysiloxane represented by the general formula (2) has 2 carbon atoms) It is preferable to have one alkenyl group of ˜6 at both ends and a part of the side chain constituting the diorganopolysiloxane.

[Component (B)]
The component (B) has the following general formula (1):
(R ¹ O) _a R ² _3-a -Si-H (1)
Wherein R ¹ is independently an unsubstituted or alkoxy group-substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, R ² is a monovalent hydrocarbon group having 1 to 13 carbon atoms, and a is (It is an integer from 1 to 3.)
It is a hydrosilyl group containing hydrocarbyl oxysilane represented by these. This component (B) is a component that acts as a modifying agent for the diorganopolysiloxane having an alkenyl group that is the component (A) and obtains the target terminal hydrocarbyloxy group-containing diorganopolysiloxane. (B) A component may be used individually by 1 type, or may use 2 or more types together.

R ¹ includes an unsubstituted monovalent hydrocarbon group such as an alkyl group having 1 to 8 carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, and an octyl group; a methoxyethyl group, an ethoxy group Examples thereof include an alkoxy group-substituted monovalent hydrocarbon group such as an alkoxy group-substituted alkyl group having 1 to 8 carbon atoms such as an ethyl group, a methoxypropyl group, and a methoxybutyl group. R ¹ is preferably a methyl group, an ethyl group, a propyl group, or a methoxyethyl group, and more preferably a methyl group or an ethyl group.

R ² includes an alkyl group having 1 to 13 carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, a decyl group and a tridecyl group; a cycloalkyl such as a cyclopentyl group and a cyclohexyl group. Groups: aryl groups having 6 to 13 carbon atoms such as phenyl group, tolyl group and naphthyl group; and aralkyl groups having 7 to 13 carbon atoms such as benzyl group, phenylethyl group and phenylpropyl group. R ² is preferably a methyl group, an ethyl group, a propyl group, or a phenyl group, and particularly preferably a methyl group.

  a is an integer of 1 to 3, preferably 2 or 3.

  Specific examples of the component (B) include trimethoxysilane, methyldimethoxysilane, triethoxysilane, and methyldiethoxysilane.

  The amount of component (B) charged is preferably such that the amount of hydrosilyl group in component (B) is 0.90 mol or more per mole of alkenyl groups in component (A), more preferably 0. The amount is in the range of .95 to 2.0 mol, particularly preferably in the range of 1.00 to 1.25 mol. When the component (B) is added so that the amount of the alkenyl group is 0.90 mol or more, the total amount of unreacted component (A) in the diorganopolysiloxane after the reaction is 10 mol%. Therefore, even if it is used as a base polymer of a one-component dealcohol-free RTV organopolysiloxane composition, the resulting one-component dealcohol-free RTV organopolysiloxane composition is likely to be sufficiently crosslinked, and the intended rubber It is easy to obtain a cured product having elasticity. The terminal hydrocarbyloxy group-containing diorganopolysiloxane can be produced without problems even if the component (B) is added in an amount exceeding 2.0 mol of the alkenyl group, but unreacted ( Since component B) remains, it is preferably removed by a separation device such as a thin film evaporator. When continuously producing a terminal hydrocarbyloxy group-containing diorganopolysiloxane, a separation device such as a thin film evaporator is installed downstream of the tubular reaction device, and the unreacted component (B) is continuously produced by the separation device. May be removed.

[Component (C)]
The platinum group metal catalyst of component (C) is used for the addition reaction of the alkenyl group in component (A) and the hydrosilyl group in component (B). As the component (C), platinum metal alone (including platinum black) used as a platinum group metal catalyst known in the silicone industry, chloroplatinic acid, alcohol-modified chloroplatinic acid, a complex of platinum and an olefin, Examples include platinum-based catalysts such as complexes of platinum and ketones, complexes of platinum and vinylsiloxane; palladium-based catalysts such as palladium metal alone; rhodium-based catalysts such as rhodium metal alone. Further, the platinum group metal catalyst dissolved or dispersed in an organic solvent such as toluene or xylene can be used.

  The amount of the component (C) is preferably 0.5 ppm or more, particularly preferably in the range of 1 to 10 ppm, based on the total of the components (A) and (B) in terms of platinum group metal. When the charged amount is 0.5 ppm or more, higher reactivity can be maintained, and the reaction time can be further effectively shortened. In addition, when the charging amount is 10 ppm or less, an improvement in reactivity according to the charging amount can be expected, and it is difficult to be disadvantageous in terms of cost.

[Method for producing terminal hydrocarbyloxy group-containing diorganopolysiloxane]
In the present invention, the reaction liquid containing the components (A) to (C) is mixed in the tubular reactor by reciprocating vibration along the axial direction of the tubular reactor, and the alkenyl group of the component (A) is mixed. The hydrosilyl group of component (B) is subjected to an addition reaction in the presence of component (C) to produce a terminal hydrocarbyloxy group-containing diorganopolysiloxane.

The raw materials for the addition reaction are simultaneously fed to the tubular reactor at a constant feed rate from a feed tank in which they are stored. At this time, even if the components (A) to (C) are supplied separately, or the two components are mixed in advance and the remaining one component is supplied separately, all components are mixed in advance May be supplied. When mixing at least two components in advance, the viscosity ratio (viscosity of one component is v. Between any two of the components so that the time required for complete mixing of these components does not become too long. It is preferable that v _a / v _b (ratio represented by v _a ≦ v _b ) is not smaller than 1/1000 when the viscosity of _a and the other component is v _b . Further, when the viscosity of the component (A) is high at room temperature, the component (A) may be heated in advance with a heat exchanger or the like to lower the viscosity and then supplied to the tubular reactor, or the component (A) Is passed through the inner pipe of the double pipe, and heated with a heat medium (steam, hot water, heated silicone oil, etc.) passed between the inner pipe and the outer pipe of the double pipe, while reducing the viscosity, the tubular reactor Alternatively, the component (A) may be dissolved in an organic solvent such as toluene, xylene, benzene, n-hexane, cyclohexane, etc., and supplied to the tubular reactor in the form of a solution having a low viscosity. When an organic solvent is used, it is preferable to remove the organic solvent remaining in the reaction liquid after being taken out from the tubular reaction apparatus with a separation apparatus such as a thin film evaporator. In the case of continuously producing a diorganopolysiloxane having terminal hydrocarbyloxy groups, a separation device such as a thin film evaporator is installed downstream of the tubular reactor, and the organic solvent is continuously removed by the separation device. Good.

  In the present invention, the (A) component diorganopolysiloxane having a high viscosity is mixed with the (B) component hydrocarbyloxysilane and the (C) component platinum group metal catalyst. Perform the reaction. In general, as a device for mixing high-viscosity products and low-viscosity products, a general batch mixer, planetary mixer, combination mix, etc. with a built-in stirrer with anchor blades etc. A mixing device is mentioned. Further, as a device capable of continuous mixing, a high-speed rotation type continuous mixing device with a jacket for uniformly mixing the contents by forcibly applying a shearing force is also used. Specific examples of such a continuous mixing device include a homomixer, a pipeline mixer, and a TK fill mix. When mixing with these rotary mixing devices, if the handling material has a higher viscosity, local heating exceeding the cooling capacity of the jacket may occur due to shear by rotation. When a high-speed rotation type continuous mixing apparatus is used, since the required power of the motor increases, the amount of stirring heat converted into the material also increases, and the tendency for the local heating to occur increases. When an end hydrocarbyloxy group-containing diorganopolysiloxane that easily undergoes thermal alteration is to be obtained by the above rotary mixing device, particularly a high speed rotary continuous mixing device, the terminal hydrocarbyloxy group is altered by the above local heating. The viscosity of the target product tends to be higher than the desired value. Moreover, volatilization of (B) component is induced and it becomes easy to lead to the fall of the reaction rate of the alkenyl group in (A) component, and the hydrosilyl group in (B) component. On the other hand, when a high viscosity product and a low viscosity product are mixed by reciprocating vibration along the axial direction in the tubular reactor, a piston flow (plug flow) along the same direction is formed. Since the occurrence of shearing is suppressed, local heating can be kept low.

  Therefore, in the present invention, the method of mixing by reciprocally vibrating the reaction liquid containing the components (A) to (C) along the axial direction of the tubular reactor in the tubular reactor was selected. As a result, the components (A) to (C) can be instantaneously and uniformly mixed, and the components (A) and (B) can be reacted efficiently in a short time in the presence of the component (C). A terminal hydrocarbyloxy group-containing diorganopolysiloxane in which an increase in viscosity is suppressed can be obtained. In particular, a reciprocating vibration of the reaction liquid containing the components (A) to (C) is generated by reciprocatingly vibrating an agitator provided in the tubular reaction apparatus and reciprocally vibrating along the axial direction of the tubular reactor. It is preferable to mix the reaction solution. The reciprocating vibration of the stirrer promotes the stretching and reversal action of the material in the tubular reactor, and the components (A) to (C) are more uniformly and uniformly mixed. In order to further improve the efficiency of mixing, the stirring body preferably has, for example, a spiral plate. In addition, by continuously supplying the components (A) to (C) to the tubular reactor and collecting the reaction liquid from the tubular reactor, the residence time in the tubular reactor is shortened. A terminal hydrocarbyloxy group-containing diorganopolysiloxane can be continuously produced.

  The supply of the raw material into the tubular reactor is preferably performed by a linear pump, a gear pump, a sine pump or the like that can supply the raw material at a constant flow rate without pulsation as much as possible.

  The temperature in the tubular reactor is preferably 70 to 150 ° C, more preferably 80 to 110 ° C. When the temperature is 70 to 150 ° C., the catalytic activity of the platinum group metal catalyst as the component (C) is sufficiently exerted, so that the reaction time can be prevented from becoming too long. Since the terminal hydrocarbyloxy group-containing diorganopolysiloxane is less affected by thermal history, the terminal hydrocarbyloxy group is less likely to be altered, and thus the viscosity does not become too high. The tubular reactor preferably has a jacket, and in order to stably maintain the temperature inside the apparatus, a coolant such as cooling water, steam, warm water, heated silicone oil or other heat medium is allowed to flow through the jacket, and external heat is supplied. It is preferable to control the temperature with an exchange or the like.

  The reaction can be carried out in the absence of a solvent or in an organic solvent. When the reaction is carried out in an organic solvent, it is preferable to remove the organic solvent remaining in the reaction solution in the same manner as described above. Examples of the organic solvent include toluene, xylene, benzene, n-hexane, cyclohexane and the like.

  Among the tubular reactors used in the present invention, in particular, as a specific example of a tubular reactor equipped with a stirring body that reciprocally vibrates along the axial direction in the tubular reactor, Vibro Mixer manufactured by Chilling Industries Co., Ltd. Etc. Also, a mixing device in which a mechanism for generating reciprocal vibration is added to a normal static mixer for stirring and mixing the solution can be used.

  FIG. 1 is a schematic view showing an example of a production system including a tubular reactor used in the present invention, which is based on the above-mentioned Vibro mixer. The manufacturing method of the present invention will be described below with reference to FIG. A production system 1 shown in FIG. 1 includes a tubular reaction device 2, raw material supply devices 3 and 4, and a reaction liquid recovery device 5. The tubular reactor 2 includes a reaction tube 6, a stirring body 7 disposed on an axis in the reaction tube 6, and a motor 9 provided below the reaction tube 6 and connected to the stirring body 7 via a shaft 8. The raw material supply ports 10 and 11 provided in the lower part of the reaction tube 6, the reaction liquid recovery port 12 provided in the upper part of the reaction tube 6, and the jacket 13 provided around the reaction tube 6. The reaction tube 6 is divided by a partition wall 14 into six mixer chambers 15a to 15f having the same volume. The stirring body 7 includes a support bar 7a and a spiral plate 7b provided around the support bar 7a. The vertical motion generated by the operation of the motor 9 is transmitted to the stirring body 7 through the shaft 8, and the stirring body 7 reciprocates along the axial direction of the reaction tube 6. The raw material supply device 3 includes a feed tank 16 for the raw material 1, a raw material supply pipe 17 having one end connected to the feed tank 16, and a pump 18 provided in the middle of the raw material supply pipe 17. The other end of the raw material supply pipe 17 is connected to the reaction tube 6 through the raw material supply port 10. The raw material supply apparatus 4 includes a feed tank 19 for the raw material 2, a raw material supply pipe 20 having one end connected to the feed tank 19, and a pump 21 provided in the middle of the raw material supply pipe 20. The other end of the raw material supply pipe 20 is connected to the reaction tube 6 through the raw material supply port 11. The raw materials 1 and 2 are supplied to the reaction tube 6 by the pumps 18 and 21, respectively. The reaction liquid recovery apparatus 5 includes a receiver 22 for recovering the reaction liquid, and a reaction liquid recovery pipe 23 connected to the receiver 22 and having one end disposed inside the receiver 22. The other end of the reaction solution recovery tube 23 is connected to the reaction tube 6 through the reaction solution recovery port 12. The jacket 13 is supplied with a heating medium such as warm water controlled at a predetermined temperature from a heating medium circulation device (not shown) such as a warm water circulation device, and maintains the inside of the reaction tube 6 at a constant temperature.

  In the production system 1, a heating medium such as warm water controlled at a predetermined temperature is supplied to the jacket 13 from a heating medium circulation device (not shown) such as a warm water circulation device in advance, and the inside of the reaction tube 6 is suitable for an addition reaction. Keep at temperature. The motor 9 is operated to vibrate the stirring member 7 up and down. At the same time, the pumps 18 and 21 are operated to supply the raw material 1 from the feed tank 16 through the raw material supply pipe 17 to the reaction tube 6 and supply the raw material 2 from the feed tank 19 through the raw material supply pipe 20 to the reaction tube 6. Examples of the raw material 1 include (A) component diorganopolysiloxane, and examples of the raw material 2 include (B) component hydrocarbyloxysilane and (C) component platinum group metal catalyst. Can be mentioned. The raw materials 1 and 2 supplied into the reaction tube 6 are instantaneously and uniformly mixed by the action of the spiral plate 7b included in the stirring body 7 that reciprocally vibrates up and down, and the addition reaction starts. The reaction proceeds while the reaction solution sequentially passes through the mixer chambers 15a to 15f. The reaction solution reaching the upper part of the reaction tube 6 exits from the reaction tube 6 and is collected in the receiver 22 through the reaction solution collection tube 23. If necessary, a separation device such as a thin film evaporator is installed downstream of the receiver 22 or in the middle of the reaction solution recovery pipe 23, and the reaction solution is supplied to the separation device so that the unreacted component (B) is removed. It is continuously separated from the reaction solution.

  The manufacturing method of the present invention can also be implemented by the manufacturing system shown in FIG. FIG. 2 is a schematic view showing another example of a production system including a tubular reactor used in the present invention, and is based on a Vibro mixer as in FIG. Hereinafter, the manufacturing method of the present invention will be described with reference to FIG. The manufacturing system 24 shown in FIG. 2 is the same as the manufacturing system 1 except that the raw material supply device 25 is used instead of the raw material supply device 4 in the manufacturing system 1 shown in FIG. The raw material supply device 25 includes a feed tank 26a for the raw material 2a, a raw material supply pipe 27a having one end connected to the feed tank 26a, a pump 28a provided in the middle of the raw material supply pipe 27a, a feed tank 26b for the raw material 2b, A raw material supply pipe 27b having one end connected to the feed tank 26b, a pump 28b provided in the middle of the raw material supply pipe 27b, and a raw material supply pipe 27 extending in one direction from the junction of the raw material supply pipes 27a and 27b. . The other end of the raw material supply pipe 27 is connected to the reaction tube 6 through the raw material supply port 11. The raw material 2a is supplied from the feed tank 26a to the reaction tube 6 through the raw material supply tubes 27a and 27 by the pump 28a. On the other hand, the raw material 2b is supplied from the feed tank 26b to the reaction tube 6 through the raw material supply tubes 27b and 27 by the pump 28b. If necessary, a mixing device such as a static mixer may be installed at the junction of the raw material supply pipes 27a and 27b.

  In the production system 2, the raw material 1 includes, for example, the (A) component diorganopolysiloxane, the raw material 2a includes, for example, the (B) component hydrocarbyloxysilane, and the raw material 2b includes, for example, , (C) component platinum group metal catalyst. The raw materials 1, 2 a and 2 b are supplied to the reaction tube 6 by operating the motor 9 to reciprocate the stirring body 7 up and down and operating the pumps 18, 28 a and 28 b. The raw materials 1, 2a and 2b supplied into the reaction tube 6 are instantaneously and uniformly mixed by the action of the spiral plate 7b provided in the stirring body 7 which reciprocally vibrates up and down, and an addition reaction starts. Other operations are the same as when the manufacturing system 1 is used.

[Terminal hydrocarbyloxy group-containing diorganopolysiloxane]
According to the production method of the present invention, the following general formula:
(R ¹ O) _a R ² _3-a -Si-A-
(Wherein R ¹ , R ² and a are as defined above, and A is an alkylene group.)
A terminal hydrocarbyloxy group-containing diorganopolysiloxane having a structure represented by the following formula can be obtained. In particular, when the diorganopolysiloxane represented by the general formula (2) is used as the component (A), the following general formula (3):
R ⁵ _b -R ³ _3-b SiO (R ⁴ ₂ SiO) _n (R ⁵ _2-c R ⁴ _c SiO) _m SiR ³ _{3-b '} -R ⁵ _b' (3)
(Wherein R ³ , R ⁴ , b, b ′, c, m and n are as defined above, and R ⁵ represents the following general formula:
(R ¹ O) _a R ² _3-a -Si-Y-
(Wherein R ¹ , R ² and a are as defined above, and Y is an alkylene group having 2 to 6 carbon atoms.)
The structure represented by is shown. )
The terminal hydrocarbyloxy group containing diorganopolysiloxane represented by these can be obtained. Specific examples of A and Y include an alkylene group having 2 to 6 carbon atoms such as an ethylene group, a propylene group, a butylene group, and a hexylene group.

  Hereinafter, the present invention will be described with reference to examples and comparative examples, but the present invention is not limited to these examples. In the following examples, the viscosity is a value at 25 ° C. measured with a rotational viscometer. In addition, the ratio of the non-volatile content in the reaction solution is obtained by accurately weighing 10 g of the reaction solution on an aluminum petri dish with a diameter of 6.5 cm and dividing the mass after being left in the atmosphere at 150 ° C. for 3 hours by the mass before leaving. It is the obtained value.

[Example 1]
A production system 1 shown in FIG. 1 was constructed based on a Vibro mixer (VIBRO LABO35 manufactured by Chilling Industries Co., Ltd.). Using this production system 1, supply of raw materials, addition reaction, and recovery of a reaction solution were performed. The Vibro mixer (VIBRO LABO35 manufactured by Chilling Industries Co., Ltd.) is a continuous mixing device that includes a mixer section, a main liquid section, and an additive liquid section. The reaction apparatus 2, the raw material supply apparatus 3, and the raw material supply apparatus 4 were used. The mixer section has a reaction tube 6 having a total volume of 144 ml, which is composed of six mixer chambers 15a to 15f, and is provided with a jacket 13 around the reaction tube 6. A heat medium (specifically, silicone oil heated to 90 ° C. in advance; the same applies hereinafter) was supplied by a heat medium circulation device (not shown), and the temperature of the jacket 13 was controlled to 90 ° C. Dimethyl polysiloxane (raw material 1) having a viscosity of 30,800 mPa · s and having both molecular chain ends blocked with vinyl groups was placed in the feed tank 16. On the other hand, 64.6 g of trimethoxysilane and 7.6 g of a toluene solution of chloroplatinic acid having a platinum concentration of 0.5% by mass were mixed at 200 rpm for 10 minutes with a reciprocating vibrator (trade name: LABORATORY SHAKER (NX-33D), manufactured by Nissin Science). A mixed liquid (raw material 2) was prepared by mixing, and placed in the feed tank 19. The motor 9 is operated to vibrate the stirring member 7 back and forth (frequency 15 times / second, amplitude 6 mm), and the pumps 18 and 21 are further operated to bring the dimethylpolysiloxane to 150 ml / min at room temperature. The reaction mixture 6 was fed into the reaction tube 6 at a feed rate (corresponding to a vinyl group feed rate of 0.00584 mol / min) at a feed rate of 0.9 ml / min (corresponding to a hydrosilyl group feed rate of 0.00695 mol / min). The raw materials 1 and 2 were mixed at the same time continuously for a minute, and an addition reaction was performed. At this time, the temperature at the raw material supply ports 10 and 11 of the reaction tube 6 was 29 ° C., and the temperature at the reaction liquid recovery port 12 of the reaction tube 6 was 106 ° C. In the reaction tube 6, the residence time of the reaction solution was approximately 1 minute. Furthermore, the platinum concentration during continuous supply was equivalent to 3.1 ppm with respect to the feedstock.

  The reaction solution was continuously recovered in a receiver 22 installed at the end of the reaction solution recovery tube 23. The obtained reaction liquid was a pale yellow transparent liquid having a viscosity of 38,240 mPa · s and a nonvolatile content of 99.9% by mass. The thickening ratio (that is, the viscosity of the reaction solution / the viscosity of the raw material dimethylpolysiloxane; the same applies hereinafter) was 1.24.

When 100 g of the obtained reaction solution and 1.0 g of tetrapropyl titanate were mixed, they did not immediately thicken and were cured after one day. From this, it was confirmed that trimethoxysilane was added to at least a part of the vinyl groups present at both ends of the raw material dimethylpolysiloxane. Separately, as a result of analyzing the obtained reaction liquid with a ²⁹ Si-NMR analyzer, trimethoxysilane was added to both ends of dimethylpolysiloxane in the reaction liquid, and the terminal vinyl group disappeared. Was confirmed. In this dimethylpolysiloxane, the content of trimethoxysilyl groups (that is, (number of moles of tridimethylsilyl group containing trimethoxysilyl groups) / (number of moles of all dimethylpolysiloxane terminals) × 100. The same applies hereinafter) was 100 mol%.

[Example 2]
In Example 1, the feed rate of the raw material 1 was changed from 150 ml / min to 75 ml / min (corresponding to a vinyl group feed rate of 0.00292 mol / min), and the feed rate of the raw material 2 was changed from 0.9 ml / min to 0.4 ml / min. The addition reaction was carried out in the same manner as in Example 1 except that the time was changed to min (corresponding to a hydrosilyl group supply rate of 0.00328 mol / min) and the continuous supply time to the reaction tube 6 was changed from 20 minutes to 40 minutes. went. At this time, the temperature at the raw material supply ports 10 and 11 of the reaction tube 6 was 31 ° C., and the temperature at the reaction liquid recovery port 12 of the reaction tube 6 was 117 ° C. In the reaction tube 6, the residence time of the reaction solution was approximately 2 minutes. Furthermore, the platinum concentration during continuous supply was equivalent to 2.8 ppm with respect to the feedstock.

  The reaction solution was recovered in the same manner as in Example 1. The obtained reaction liquid was a pale yellow transparent liquid having a viscosity of 39,680 mPa · s and a nonvolatile content of 99.9% by mass. The thickening rate was 1.29.

When 100 g of the obtained reaction solution and 1.0 g of tetrapropyl titanate were mixed, they did not immediately thicken and were cured after one day. From this, it was confirmed that trimethoxysilane was added to at least a part of the vinyl groups present at both ends of the raw material dimethylpolysiloxane. Separately, as a result of analyzing the obtained reaction liquid with a ²⁹ Si-NMR analyzer, trimethoxysilane was added to both ends of dimethylpolysiloxane in the reaction liquid, and the terminal vinyl group disappeared. Was confirmed. In this dimethylpolysiloxane, the content of trimethoxysilyl groups was 100 mol%.

[Comparative Example 1]
As a high-speed rotary continuous mixing device with a jacket that forcibly applies shearing force to uniformly mix the contents, a TK fill mix (TK fill mix 80-50 manufactured by Primics) with a mixer capacity of 250 ml was used. . The heat medium was supplied by a heat medium circulation device, and the temperature of the jacket was controlled at 90 ° C. At room temperature, the raw material 1 of Example 1 was fed at a feed rate of 200 ml / min (corresponding to a vinyl group feed rate of 0.00779 mol / min) and the raw material 2 of Example 1 was fed at a feed rate of 1.3 ml / min (hydrosilyl group). At a feed rate of 0.00965 mol / min), the TK fill mix was continuously fed simultaneously for 30 minutes, and raw materials 1 and 2 were mixed to carry out an addition reaction. At this time, the temperature at the inlet of the TK fill mix was 28 ° C., and the temperature at the outlet of the TK fill mix was 116 ° C. In the TK fill mix, the residence time of the reaction solution was approximately 1.3 minutes. Furthermore, the platinum concentration during continuous supply was equivalent to 3.3 ppm relative to the feedstock. The rotational speed of the TK fill mix was set to a peripheral speed of 10 m / s (corresponding to 2,500 rpm).

  The reaction solution was continuously collected in a receiver installed at the outlet of the TK fill mix. The obtained reaction liquid was a pale yellow transparent liquid having a viscosity of 83,360 mPa · s and a non-volatile content of 99.8% by mass. The thickening rate was 2.71.

When 100 g of the obtained reaction solution and 1.0 g of tetrapropyl titanate were mixed, they did not immediately thicken and were cured after one day. From this, it was confirmed that trimethoxysilane was added to at least a part of the vinyl groups present at both ends of the raw material dimethylpolysiloxane. Separately, as a result of analyzing the obtained reaction solution with a ²⁹ Si-NMR analyzer, trimethoxysilane was added to a part of the ends of dimethylpolysiloxane in the reaction solution, and the remaining ends were vinyl group. Confirmed to remain. In this dimethylpolysiloxane, the content of trimethoxysilyl groups was 47 mol%.

  Compared with the Examples, the reaction solution obtained in Comparative Example 1 had a significantly high viscosity increase rate and a low content of trimethoxysilyl groups.

[Comparative Example 2]
Viscosity of 30,800 mPa · s with both ends of the molecular chain blocked with vinyl groups in a 500 mL four-necked flask equipped with a thermometer, stirrer, cooler, nitrogen gas inlet pipe, gas outlet pipe and dropping funnel Charge 270 g of dimethylpolysiloxane (equivalent to 0.010 mol of vinyl group), 0.15 g of toluene solution of chloroplatinic acid with a platinum concentration of 0.5% by mass (platinum concentration is equivalent to 2.8 ppm with respect to the total amount of charged raw materials) at 250 rpm While stirring, the temperature was raised to 80 ° C. over 1 hour. After raising the temperature to 80 ° C., 1.4 g of trimethoxysilane (corresponding to 0.011 mol of hydrosilyl group) was added dropwise over 1 minute. Thereafter, the temperature was raised to 90 ° C., an addition reaction was carried out for 1 hour, and aging was carried out at 90 ° C. for 1 hour to obtain 254 g of a pale yellow transparent liquid having a viscosity of 40,200 mPa · s and a nonvolatile content of 99.9% by mass. The thickening rate was 1.31.

When 100 g of the obtained reaction solution and 1.0 g of tetrapropyl titanate were mixed, they did not immediately thicken and were cured after one day. From this, it was confirmed that trimethoxysilane was added to at least a part of the vinyl groups present at both ends of the raw material dimethylpolysiloxane. Separately, as a result of analyzing the obtained reaction liquid with a ²⁹ Si-NMR analyzer, trimethoxysilane was added to both ends of dimethylpolysiloxane in the reaction liquid, and the terminal vinyl group disappeared. Was confirmed. In this dimethylpolysiloxane, the content of trimethoxysilyl groups was 100 mol%.

  The method of Comparative Example 2 required a great amount of time of about 3 hours for the temperature rise, the addition reaction, and the aging after the raw materials were charged.

DESCRIPTION OF SYMBOLS 1 Manufacturing system 2 Tubular reaction apparatus 3, 4 Raw material supply apparatus 5 Reaction liquid collection apparatus 6 Reaction tube 7 Stirring body 7a Support rod 7b Spiral plate 8 Shaft 9 Motor 10, 11 Raw material supply port 12 Reaction liquid collection port 13 Jacket 14 Partition 15a ˜15f Mixer chamber 16, 19 Feed tank 17, 20 Raw material supply pipe 18, 21 Pump 22 Receiver 23 Reaction liquid recovery pipe 24 Production system 25 Raw material supply device 26a, 26b Feed tank 27a, 27b Raw material supply pipe 28a, 28b Pump

Claims (5)

(A) a diorganopolysiloxane having an alkenyl group,
(B) The following general formula (1):
(R ¹ O) _a R ² _3-a -Si-H (1)
Wherein R ¹ is independently an unsubstituted or alkoxy group-substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, R ² is a monovalent hydrocarbon group having 1 to 13 carbon atoms, and a is (It is an integer from 1 to 3.)
(C) A reaction solution containing a hydrocarbyloxysilane containing a hydrosilyl group and a platinum group metal catalyst is mixed in a tubular reactor by reciprocating vibration along the axial direction of the tubular reactor, A) component and (B) component are reacted in the presence of component (C), the following general formula:
(R ¹ O) _a R ² _3-a -Si-A-
(Wherein R ¹ , R ² and a are as defined above, and A is an alkylene group.)
A process for producing a terminal hydrocarbyloxy group-containing diorganopolysiloxane having a structure represented by the formula:   The production according to claim 1, wherein the reciprocating vibration of the reaction liquid is generated by reciprocating vibration of an agitator that is provided in the tubular reaction apparatus and reciprocates along the axial direction of the tubular reaction apparatus. Method.   The production method according to claim 1 or 2, wherein the supply of the components (A) to (C) to the tubular reactor and the recovery of the reaction liquid from the tubular reactor are continuously performed. The component (A) is represented by the following general formula (2):
X _b -R ³ _3-b SiO (R ⁴ ₂ SiO) _n (X _2-c R ⁴ _c SiO) _m SiR ³ _{3-b '} -X _b' (2)
(Wherein R ³ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 6 carbon atoms other than an alkenyl group, and R ⁴ is independently an unsubstituted or substituted carbon atom having 1 to 13 carbon atoms. X is an alkenyl group having 2 to 6 carbon atoms, b and b 'are integers of 0 to 3, c is 0 or 1, and m is 0 to 10 (It is an integer, n is an integer of 10 or more, provided that b + b ′ + m (2-c) is an integer of 1 or more.)
A diorganopolysiloxane represented by:
The terminal hydrocarbyloxy group-containing diorganopolysiloxane is represented by the following general formula (3):
R ⁵ _b -R ³ _3-b SiO (R ⁴ ₂ SiO) _n (R ⁵ _2-c R ⁴ _c SiO) _m SiR ³ _{3-b '} -R ⁵ _b' (3)
(Wherein R ³ , R ⁴ , b, b ′, c, m and n are as defined above, and R ⁵ represents the following general formula:
(R ¹ O) _a R ² _3-a -Si-Y-
(Wherein R ¹ , R ² and a are as defined above, and Y is an alkylene group having 2 to 6 carbon atoms.)
The structure represented by is shown. )
The manufacturing method which concerns on any one of Claims 1-3 represented by these.   The amount of component (B) charged is such that the amount of hydrosilyl group in component (B) is 0.90 mol or more per mole of alkenyl group in component (A). The manufacturing method which concerns on.

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