JP2001087724A - Cleaning method of reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning method capable of performing repeatingly a polymer modification reaction with the reduction of solvent working cost and the quantity of the waste solvent. SOLUTION: In the case of repeating a process for obtaining an objective product having >=0.1 poise viscosity by the polymer modification reaction using a batch process in a reactor, after the polymer modification reaction is carried out and the objective product is discharged from the reactor, the vapor of a cleaning solvent is introduced into the reactor to clean off and discharge the remaining objective product, the discharged condensed cleaning solvent is sent to a cleaning liquid evaporating device to be vaporized, introduced again into the reactor as the vapor of the cleaning liquid to recycle for the next cleaning of the reactor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning a reactor when a reaction is continuously and repeatedly performed by a batch method.

[0002]

2. Description of the Related Art Techniques for modifying polymers by chemical modification are generally known. Examples of such techniques include hydrosilylation, hydroformylation, carboxylation, epoxidation, oxidation, and hydrogenation of alkenyl groups. Is known to. In these reactions, a method of continuously repeating the reaction by a batch method using an organometallic catalyst is generally used. However, depending on the main chain skeleton and the molecular weight of the polymer, the viscosity of the reaction field may be zero. .. May be performed in an area exceeding 1 poise.

The product after the completion of the reaction is generally degassed to remove volatile components such as a solvent and residual monomers, and then added with an additive or the like, mixed and discharged as a product.
However, when the product is dispensed in this way, a part of the product adhered to the reactor wall or the like remains in the reactor, and when the next batch reaction is performed, the catalyst is poisoned and a normal reaction is performed. May not be possible.

For example, a reaction in which a silicon hydride compound having a Si—H group is added to an alkenyl group (carbon-carbon unsaturated bond) is generally called a hydrosilylation reaction, which is disclosed in Japanese Patent Application Laid-Open No. 9-208624. It has been reported that a paraffin-based process oil is used in combination to reduce the viscosity of the reaction field, and when these are oxidized, the reaction is deactivated.

[0005] As described above, when the target product lowers the reaction of the next batch, usually, the organic solvent compatible with the target product is charged to the reactor in a full state, stirred and dissolved, and then washed. As described in Japanese Patent Application Laid-Open No. 9-296008, cleaning is generally performed by cleaning and discharging the wall side from a shower nozzle.

[0006] When the polymer modification reaction is completed by the batch method and the product is dispensed, and when the product viscosity at the time of dispensing exceeds 0.1 poise, the product adhering to the can wall or the like in the reactor is removed. The residual amount increases as compared with the case where ordinary organic solvents and water are discharged. If the remaining product is mixed into the next batch, it may inhibit the polymer modification reaction or cause a reduction in product quality. In order to prevent such contamination of the reaction field with impurities, it is necessary to repeatedly wash the product using an organic solvent compatible with the product until the effect is eliminated.However, such a method increases the amount of the organic solvent used for cleaning. As a result, the use cost of the solvent increases and the amount of the waste solvent increases, which is disadvantageous in terms of economic efficiency and environmental load.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to connect a simple cleaning liquid evaporator to a reactor, introduce a vaporized cleaning liquid into the reaction liquid, perform cleaning, and vaporize a generated discharge liquid to repeat the vaporization. It is an object of the present invention to provide a cleaning method which can reduce the cost of using a solvent and the amount of a waste solvent and can repeatedly carry out a denaturation reaction by using it as a cleaning liquid.

[0008]

That is, in the present invention, the polymer modification reaction is carried out by repeating the step of obtaining a target product having a viscosity of 0.1 poise or more by performing a polymer modification reaction by a batch method in a reactor. After the target product is discharged from the reactor, the vapor of the cleaning solvent is introduced into the reactor to clean and discharge the remaining target product inside, and the discharged condensed cleaning solvent is sent to the cleaning liquid evaporator. This is a method for cleaning the reactor, which comprises vaporizing the solution, introducing the solvent again as vapor of the cleaning solvent into the reactor, and reusing it for the subsequent cleaning of the reactor.

In the present invention, the step of obtaining a target product having a viscosity of 0.1 poise or more by a polymer modification reaction is repeatedly carried out using the same reactor by a batch method.
After the completion of the polymer modification reaction, the target product is discharged from the reactor, and then the washing solvent vaporized by an evaporator is introduced into the reactor to wash and discharge the remaining target product inside, and then discharged. Performing at least once a washing step in which the condensed washing solvent is sent to the evaporator in order to reuse the condensed washing solvent for washing the reactor, and charging the reactants again to the reactor to perform the polymer modification reaction. And a continuous method for carrying out the polymer modification reaction. Hereinafter, the present invention will be described in detail.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a reaction product obtained by a polymer modification reaction is discharged from a reactor as a high-viscosity product, and then a solvent vapor is introduced from a washing liquid evaporator as shown in FIG. Then, the target product residue in the reactor is washed and discharged.

The organic solvent used for washing may be any organic solvent that is compatible with the target product when it is discharged from the reaction tank. Depending on the type of the target product, aromatic hydrocarbons, aliphatic hydrocarbons, and halogenated organic solvents may be used. Although hydrocarbons and the like are used, it is preferable to use an inexpensive organic solvent inert to the polymer modification reaction. Of these, hydrocarbon solvents inert to the polymer modification reaction are preferred.

Specific examples of the organic solvent that can be used when the polymer modification reaction is a hydrosilylation reaction described below include hexane, heptane, octane, cyclohexane, and the like.
Examples thereof include aliphatic hydrocarbons such as methylcyclohexane, and aromatic hydrocarbons such as toluene and xylene, and hexane, heptane and toluene are particularly preferable in terms of the unit price of the solvent and the boiling point.

The amount of the organic solvent to be introduced into the reactor is not particularly limited, but from the viewpoint of time cycle and prevention of idle operation of the stirring lower bearing of the reactor.
The amount is preferably 0.05 to 0.5 times the reactor volume. In addition,
The reactor is usually equipped with a stirring device.

The amount of the residue of the target product mixed in the cleaning liquid may be any amount as long as the cleaning liquid can be substantially discharged from the cleaning liquid evaporator, and is operated in such an amount that the concentration of the target product in the cleaning liquid is less than 70%. Is preferred. This is because, when the viscosity of the cleaning liquid increases, the heat transfer from the heating unit in the evaporator decreases, the operation time increases, and the productivity decreases.

After the solvent vapor has condensed in the reactor, the stirring blades can be activated for a certain period of time to stir for more effective cleaning. That is, when the stirring blade is activated after the solvent vapor has condensed and adhered to the inside of the reactor, particularly to the inner wall surface, the solvent liquid is uniformly formed into a liquid film on the wall surface, so that the cleaning effect is enhanced. The number of washing operations for one batch reaction is not particularly limited, but is preferably 1 to 3 times.

The method of heating the cleaning liquid evaporator is not particularly limited, but a jacket heating method, an internal coil heating method, or the like can be selected. The heating temperature of the cleaning liquid may be substantially equal to or higher than the boiling point of the cleaning solvent to be used, but is preferably set to be higher than the boiling point of the organic solvent to be used by 10 ° C. or higher from the viewpoint of the cleaning operation time.

According to a preferred embodiment of the present invention, when a modification reaction of a polymer is carried out by a batch method, a target product, that is, a reaction product, or a product obtained after the completion of the reaction is commercialized (that is, the reaction product is degassed and reacted). After removing volatile components such as a solvent and residual monomers contained in the mixture and adding a desired additive, the dispensing valve is closed, and a heating unit connected to a reactor as shown in FIG. An organic solvent vapor compatible with the product is introduced from the cleaning liquid evaporator having the above, and after being condensed by the jacket portion in a certain amount, stirring is performed for a certain period of time to perform the cleaning operation, and the cleaning liquid is sent again to the cleaning liquid evaporator. To clean the reactor. By such an operation, the cleaning liquid can dissolve the reaction tank residue to a concentration that cannot be substantially discharged from the cleaning liquid evaporator, and can generate and reuse the solvent as cleaning vapor.

The polymer modification reaction applicable to the present invention includes:
The advantages of the present invention can be advantageously exhibited by targeting those which produce a target product having a viscosity of 0.1 poise or more. Among them, it can be suitably used for reacting a functional group in a polymer with a reaction substrate using an organometallic catalyst, and examples thereof include a hydrosilylation reaction, a hydroformylation reaction, a carboxylation reaction, an epoxidation reaction, and a hydrogenation reaction. No. In particular, it can be suitably used for a hydrosilylation reaction of a polymer.

An embodiment of the hydrosilylation reaction that can be suitably used will be described in more detail. Specifically, (A) a general formula (1): R _a X _b H _c Si (1) (wherein, R is an alkyl group having 1 to 20 carbon atoms, an aryl group or a triorganosiloxy group, and a is In the case of two or more, a plurality of Rs may be the same or different.
X is a halogen, an alkoxy group, an acyloxy group or a hydroxyl group. When b is 2 or more, a plurality of Xs may be the same or different. a and b are each an integer of 0 to 3, c is an integer of 1 to 3, and a + b + c = 4 is satisfied. ) And (B) a polymer containing an alkenyl group (carbon-carbon unsaturated bond) in a hydrosilylation reaction in the presence of (C) a catalyst containing a Group 8 metal. It can be favorably applied to the hydrosilylation reaction method characterized by the above.

A specific mode for carrying out the present invention will be described in detail. In the present invention, as the silicon compound (A) represented by the general formula (1), conventionally known compounds can be used without any particular limitation. Specifically, for example, trichlorosilane, methyldichlorosilane, dimethyl Halogenated silanes such as chlorosilane and trimethylsiloxydichlorosilane; alkoxysilanes such as trimethoxysilane, triethoxysilane, dimethoxymethylsilane and methoxydimethylsilane; acyloxysilanes such as methyldiacetoxysilane; dimethylsilane; trimethylsiloxy S in molecules such as methylsilane
Examples include hydrosilanes having two or more i-H bonds, alkenyloxysilanes such as methyldi (isopropenyloxy) silane, and among these, methyldichlorosilane, dimethoxymethylsilane, diethoxymethylsilane, and trisilane Methoxysilane, triethoxysilane and the like can be mentioned.

The amount of the silicon compound represented by the general formula (1) of the present invention is not particularly limited, but is usually 0.1 to 20 with respect to 1 mol of the alkenyl group of the polymer.
Although it is molar, it is economically preferable that it is 0.5 to 3 mol.

Catalyst containing Group 8 metal used in the present invention
(C) is usually cobalt, nickel, ruthenium, b
Indium, palladium, iridium, platinum (platinum)
A simple substance of these Group 8 metals, a metal salt
Alternatively, it is used as a complex with an organic compound. concrete
For example, simple platinum, alumina, silica, carbon
White on a carrier with solid platinum supported on a carrier such as black
Gold metal, chloroplatinic acid, chloroplatinic acid and alcohol, alde
Platinum compounds such as complexes with hydrides and ketones, platinum-ole
Fin complex [eg Pt (CH_Two = CH_Two )_Two (PPh
_Three ), Pt (CH _Two = CH_Two )_Two Cl_Two ], Platinum-vinyl
Siloxane complex [Pt @ (vinyl) Me_Two SiO
SiMe_Two (Vinyl)｝, Pt ｛Me (viny)
l) SiO｝ _Four ], A platinum-phosphine complex [Ph (PP
h_Three )_Four , Pt (PBu_Three )_Four ], Platinum-phosphite
Complex [Pt @ P (OPh)_Three ｝_Four And the like are preferred.
Good. Dicarbonyldichloroplatinum and Ashby in the United States
Patents 3,159,601 and 3,159,662
And a platinum-hydrocarbon complex described in Lamor
eaux in U.S. Pat. No. 3,220,972.
Also preferred are the platinum-alcoholate catalysts described. Further, M
Odic in US Pat. No. 3,516,946.
The prepared platinum chloride-olefin composite is also effective.

These catalysts may be used alone,
Two or more kinds may be used in combination. Chloroplatinic acid, a platinum-olefin complex, a platinum-acetylacetonate complex, and a platinum-vinylsiloxane complex are preferable because of their relatively high reaction activity.

The amount of the catalyst used is not particularly limited. Usually, the platinum catalyst is used in an amount of 10 ^-1 to 10 ^-8 mol, and is used in an amount of 10 ^-3 to 10 ^-6 mol per mol of the alkenyl group. Is preferred. If the amount of the catalyst is less than 10 ^-8 mol, the hydrosilylation reaction may not proceed sufficiently. If the amount of the catalyst is too large, the raw material cost increases,
The mixing of the catalyst residue causes problems such as coloring of the product and deterioration of the transparency.

The compound containing an alkenyl group (carbon-carbon unsaturated bond) in the present invention includes, for example, alpha-olefins such as ethylene, propylene, 1-butene and 1-hexene, and cyclohexene and trans-
Examples thereof include 2-hexene, butadiene, decadiene and allyltrimethylsilane. Various organosilicon compounds can be efficiently produced by hydrosilylation of these compounds.

Further, a polymer having an alkenyl group (carbon-carbon unsaturated bond) is subjected to a hydrosilylation reaction with a compound represented by the general formula (1), so that a hydrolyzable silyl group or the like is terminated. Can be obtained. The hydrolyzable silyl group (Si-X) is a group that gives a silanol group (Si-OH) by a hydrolysis reaction. A siloxane bond (Si-O-Si) can be given by a condensation reaction (silanol condensation) between the hydrolyzable silyl group (Si-X) and the silanol group (Si-OH).

When a polymer having an alkenyl group (carbon-carbon unsaturated bond) is used, the main chain of the polymer is not particularly limited, and examples thereof include a hydrocarbon-based main chain, a halogenated hydrocarbon-based main chain, and a saturated hydrocarbon. Hydrogen-based main chain, polyether-based main chain,
Examples include a polyester-based main chain, a polyamide-based main chain, and a polyimide-based main chain. Above all, those comprising isobutylene are preferred. Preferred as the main chain component of the polymer having a silyl group are isobutylene and olefins having 5 to 12 carbon atoms, conjugated dienes, non-conjugated dienes, vinyl ethers, aromatic vinyl compounds, norbornenes, cyclopentadiene, Examples thereof include polymers such as dicyclopentadiene and vinylsilane, and polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

Particularly preferable polymers having an alkenyl group (carbon-carbon unsaturated bond) include polypropylene oxide having an allyl group at the terminal and polyisobutylene having an allyl group at the terminal. The polyisobutylene having an allyl group at the terminal can be obtained, for example, by a reaction between polyisobutylene having a chlorine at the terminal and allyltrimethylsilane (JP-A-63-105005) or dienes (JP-A-4-288309).

The alkenyl group-containing polymer preferably has a number average molecular weight of 500 to 200,000 as measured by GPC using a polystyrene gel column.

The hydrosilylation reaction of the present invention can be carried out without a solvent or in the presence of a solvent. As the solvent for the hydrosilylation reaction, generally, hydrocarbons, halogenated hydrocarbons, ethers, and esters can be used, but heptane, hexane, benzene, toluene, xylene, and the like are preferably used. In particular, when a polymer containing an alkenyl group (carbon-carbon unsaturated bond) is subjected to hydrosilylation, since the polymer is often a solid or a high-viscosity liquid, the viscosity of the reaction system is reduced. It is preferable to use a solvent.

In the present invention, a plasticizer may be used as a reaction solvent in the hydrosilylation reaction of the polymer (a plasticizer is a liquid substance added to a polymer product). When the number average molecular weight of the alkenyl group-containing polymer is 500 to 200,000, it is preferable to use, for example, a paraffin plasticizer having an average molecular weight of 200 to 800 as a reaction solvent. As such a plasticizer, for example, paraffin 50 to 90%, naphthene 10 to 5
A mixture having a composition ratio of 0% and an aroma of about 1% can be exemplified. Specific examples of such a plasticizer include polybutene, hydrogenated polybutene, α-methylstyrene oligomer, biphenyl, triphenyl, triaryldimethane, alkylenetriphenyl, liquid polybutadiene, hydrogenated liquid polybutadiene, and alkyldiphenyl. Hydrocarbon compounds, BAA-15 (Daichi Chemical), P-103,
Adipate compounds such as W320 (Dainippon Ink), PN-150 (Adeka Argus), TOTM, T
Trimellitic ester compounds such as ITM (Shin Nippon Rika) and W-700 (Dainippon Ink), NS-100,
NM-26, NP-24, PS-32, PW-32, P
Petroleum-based process oils such as X-32 (Idemitsu Kosan),
Alkene-68 (Nippon Petroleum Detergent), BF-1000 (Adeka Argus), KE-828 (Arakawa Chemical), DOTP
(Shin Nippon Rika) and the like, and the alkene-68, PS-32, PW-32,
PX-32, DOTP, NS-100, TOTM, and the like are particularly preferable, but are not necessarily limited thereto.

In the present invention, the gas phase of the reactor used in the hydrosilylation reaction may be composed of only an inert gas such as nitrogen or helium, or may contain oxygen or the like. When performing the hydrosilylation reaction, the gas phase of the reactor may be carried out in the presence of an inert gas such as nitrogen or helium from the viewpoint of safety in handling combustible substances. However, when the hydrosilylation reaction is performed under the reaction conditions in which the gas phase of the reactor is replaced with an inert gas such as nitrogen or helium, there is a problem that the reaction rate may be reduced. The presence of oxygen in the gas phase may promote hydrosilylation. In the present invention, by setting the oxygen concentration in the gas phase portion of the reactor to a range that does not give an explosive mixed composition, it is possible to safely perform the hydrosilylation reaction while promoting the reaction in the presence of oxygen. . The oxygen concentration in the gas phase of the reactor is usually 0.1% or more, but 0.5 to 10%.
It is preferable that

In the case where oxygen is introduced into the gas phase in the present invention, a hydrosilylation reaction may be carried out in the presence of an antioxidant in order to prevent the reaction solvent and the plasticizer from being oxidized by oxygen. it can. Examples of the antioxidant include phenolic antioxidants having the function of a radical chain inhibitor, for example, 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butylphenol,
2,4-dimethyl-6-tert-butylphenol,
2,2-methylenebis (4-methyl-6-tert-butylphenol), 4,4-butylidenebis (3-methyl-6-tert-butylphenol), 4,4-thiobis (3-methyl-6-tert-butylphenol) , Tetrakis methylene-3 (3,5-di-ter
t-butyl-4-hydroxyphenyl) propionate @ methane, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane and the like can be used. As similar radical chain inhibitors, amine antioxidants such as phenyl-β-naphthylamine, α-naphthylamine, N, N-di-sec-
Butyl-p-phenylenediamine, phenothiazine,
N, N-diphenyl-p-phenylenediamine or the like can be used, but is not limited thereto.

The hydrosilylation reaction temperature of the present invention is usually 30 ° C. or more and 200 ° C. or less, preferably 50 ° C. or less.
The temperature can be set to not less than 120 ° C.

The sulfur compound (D) may be present in the hydrosilylation reaction system. The sulfur compound refers to a compound having a sulfur atom in the molecule, and specific examples thereof include simple sulfur, thiol, sulfide, sulfoxide, sulfone, and thioketone, but are not limited thereto. As the sulfur compound, sulfur is particularly preferable. When the sulfur compound is added to the liquid phase reaction system, the sulfur compound may be added as it is. However, if the sulfur compound is made into a solution and then added, the sulfur compound can be uniformly dispersed throughout the reaction solution. A sulfur compound such as elemental sulfur can be added after being dissolved in an organic solvent such as toluene, hexane, or xylene.

The amount of the sulfur compound added is, for example, 0.1 to 10 mols per mol of the catalyst containing a Group 8 metal.
The amount is 0.002 to 0.1 times the molar number of the alkenyl group of the compound containing the alkenyl group, or 0.01 to 500 p based on the total weight of the reaction solution.
pm. If the amount is small, the effect of the present invention may not be sufficiently achieved.
If the amount of the sulfur compound is too large, it may act as a catalyst poison to reduce the catalytic activity and inhibit the hydrosilylation reaction.

[0037]

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

(Example 1) [Blank test] 90 L of toluene was previously charged as a washing solvent in a reactor having an internal volume of 150 L, the internal temperature was set to 90 ° C, and the mixture was stirred and washed for 30 minutes, and the internal temperature was reduced to 40 ° C. Washing was performed twice to cool and remove toluene. After degassing the reactor after washing for 1 hour at 5 torr or less, a blank test of the hydrosilylation reaction of allyl-terminated polyisobutylene was performed. The reaction test method is shown below.

An allyl-terminated polyisobutylene (molecular weight: 15) produced according to the method of JP-A-63-105005
000, the number of allyl groups per polymer is 2.0) 4
0 kg is reacted with 1.4 kg of dimethoxymethylsilane. 20 kg of process oil PS-32 (Idemitsu Petroleum) was used as a reaction solvent. As a catalyst, 2.8 g of a platinum vinyl siloxane complex (0.00000831 mmol / μL xylene solution) was added. Nitrogen containing 5 vol% of oxygen was charged into the gas phase of the reactor to a pressure of 5 atm. 12 g of 2,6-di-tert-butyl-p-cresol was added as an antioxidant. 0.04 g of sulfur was dissolved in 40 g of toluene and added to the reactor. After adding dimethoxymethylsilane to start the reaction, mixing and stirring were continued at 70 ° C. for 15 hours.

A sample of the reaction solution was taken to evaluate the conversion of the allyl group in the hydrosilylation reaction, and the concentration of the allyl functional group was measured by an infrared spectrophotometer.
No residual allyl group was detected at 5 hours, and the reaction conversion was 10
It was 0%. 5 to unreacted components using a vacuum pump
The product was dispensed after degassing for 3 hours at less than rr. The silyl group-terminated polymer thus obtained was subjected to condensation crosslinking to prepare a standard (JIS No. 3 dumbbell: 5 mm wide × 2 mm thick) rubber-like cured product, and the cured product modulus was evaluated by an extension test. The condensation crosslinking was carried out by mixing at a weight ratio of 0.67 water and 2.5 tin octylate to 100 weight of the product and curing at 50 ° C. for 20 hours. A tensile test of this rubber-like cured product showed that the tensile stress (M ₅₀ ) at 50% elongation was 1.4 kg / cm ² . The results are summarized in Table 1.

[Repeated reaction test] After the product obtained in the blank test was dispensed, the dispensing valve was closed, and then about 40 L of toluene in a 60 L internal volume washing liquid evaporator having an internal coil connected to the reactor. 140 ° C
To generate toluene vapor, water was passed through the reactor jacket to condense about 30 L, and the washing liquid evaporator vapor line was closed. After the stirring of the reactor was started and the washing was carried out with stirring for 20 minutes, the washing liquid was again transferred to the washing liquid evaporator. This operation was repeated twice in total, and the residue in the reactor was washed. The remaining toluene in the reactor was degassed again under vacuum, and the above-described reaction was repeated. The results are also shown in Table 1. No residual allyl group was detected after 15 hours of reaction, and the conversion of the reaction was 1
00%. The M ₅₀ value of the final product is 1.3kg /
cm ² and the same level as the blank. The amount of toluene used per product was 0.44 kg / kg-product.

Example 2 The same operation as in Example 1 was performed except that the amount of the toluene solvent to be generated and condensed from the washing liquid evaporator was 15 L. Consumption rate of the allyl group and the M ₅₀ value of the final product are shown in Table 1. From this, as in Example 1, even when the amount of the toluene solvent was 15 L, the reaction was repeatedly carried out well. The amount of toluene used per product is 0.
22 kg / kg-product.

(Example 3) The reaction was repeated three more times by the washing method shown in Example 2. The results are also shown in Table 1. Thus, similar to Example 2, the repeated reaction was successfully performed. The amount of toluene used per product after the final batch was 0.054 kg / kg-product.

Comparative Example 1 The reaction described in Example 1 was repeated without washing the reactor. Reaction 15
The remaining allyl group after time is detected, and the reaction conversion rate is 80%.
Met. In addition, M ₅₀ value of the product after the degassing process is 0.7k
The value was as low as gf / cm ² .

(Comparative Example 2) The method of washing the reactor was repeated except that after the reaction was completed, 15 L toluene was charged into the reactor, stirred at 90 ° C for 30 minutes, cooled and discharged twice. The same reaction procedure as in Example 1 was performed. Table 1 shows the results
Shown in From this, the effect on the repetitive reaction is the same as that of the present invention, but the amount of toluene used per kg of the product is 0.4%.
4 kg / kg-product.

[0046]

[Table 1]

[0047]

Since the method of the present invention has the above-mentioned constitution, it is possible to easily carry out the polymer modification reaction in a batch manner without affecting the reaction rate or the final product analysis value. The unit can be reduced.

[Brief description of the drawings]

FIG. 1 shows a schematic diagram of a reactor and a washing apparatus in a preferred embodiment of the present invention.

[Explanation of symbols]

1. Reactor 2. 2. Washing liquid evaporator Stirring blades B _{1 to} B ₃ . Valve M. motor

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C11D 17/00 C11D 17/00 F term (reference) 3B201 AA33 AA47 AB51 BB12 BB13 BB14 BB92 BB95 CD22 4H003 DA12 DC01 ED03 4J011 DB24 4J100 AA06P BA77H CA27 HA61 HB17 HB50 HC09 HC70 HC71 HC90 HC91

Claims (12)

[Claims] When a step of obtaining a target product having a viscosity of 0.1 poise or more by repeatedly performing a polymer modification reaction by a batch method in a reactor is performed, the target product is discharged from the reactor after performing the polymer modification reaction. After that, the washing solvent vapor is introduced into the reactor to wash and discharge the remaining target product therein, and the discharged condensed washing solvent is sent to the washing liquid evaporator to be vaporized, and again the washing solvent vapor is emitted. The method for cleaning a reactor, wherein the method is introduced into the reactor and reused in the subsequent cleaning of the reactor. 2. The cleaning method according to claim 1, wherein the cleaning solvent is a hydrocarbon-based solvent that is inert to a polymer conversion reaction. 3. The polymer conversion reaction is carried out by: (A) a general formula (1): R _a X _b H _c Si (1) in the presence of a catalyst containing a Group 8 metal; Is an alkyl group, an aryl group or a triorganosiloxy group having 1 to 20 carbon atoms, and when a is 2 or more, a plurality of Rs may be the same or different.
X is a halogen, an alkoxy group, an acyloxy group or a hydroxyl group, and when b is 2 or more, a plurality of Xs may be the same or different. a and b are each an integer of 0 to 3 and c is an integer of 1 to 3, but a + b + c = 4
Meet. The cleaning method according to claim 1 or 2, which is a hydrosilylation reaction between the silicon compound represented by the formula) and the polymer (B) containing an alkenyl group. 4. The silicon compound (A) represented by the general formula (1) is one selected from the group consisting of methyldichlorosilane, dimethoxymethylsilane, diethoxymethylsilane, trimethoxysilane and triethoxysilane. The cleaning method according to claim 3, wherein 5. The cleaning method according to claim 3, wherein the main chain of the alkenyl group-containing polymer (B) is made of isobutylene. 6. The alkenyl group-containing polymer (B) has a number average molecular weight of 500 to 200,000.
The cleaning method according to 4 or 5. 7. The catalyst (C) containing a Group VIII metal may be platinum alone, chloroplatinic acid, a complex compound of chloroplatinic acid and an alcohol, aldehyde or ketone, platinum-olefin complex, platinum-vinylsiloxane complex, platinum 7. The cleaning method according to claim 4, wherein the cleaning method is at least one selected from the group consisting of a phosphine complex, a platinum-phosphite complex, and a material in which these are supported on a solid of alumina, silica or carbon black. . 8. The cleaning method according to claim 4, wherein the hydrosilylation reaction is further performed in the presence of (D) a sulfur compound. 9. The cleaning method according to claim 4, wherein the hydrosilylation reaction is further carried out in the presence of (E) a paraffinic plasticizer having an average molecular weight of 200 to 800. 10. The hydrosilylation reaction is further carried out in the presence of an antioxidant (F), so that oxygen is contained in the gas phase during the hydrosilylation reaction in an amount of 0.1% or more.
The cleaning method according to 7, 8, or 9. 11. When the step of obtaining a target product having a viscosity of 0.1 poise or more in the polymer modification reaction is repeatedly carried out using the same reactor in a batch mode, the target product is removed from the reactor after the completion of the polymer modification reaction. Then, the washing solvent vaporized by an evaporator is introduced into the reactor to wash and discharge the remaining target product therein, and the discharged condensed washing solvent is reused for washing the reactor. A method for continuously carrying out the polymer modification reaction, wherein a washing step of sending the solution to the evaporator for use is performed at least once, and the reaction material is again charged into the reactor to carry out the polymer modification reaction. . 12. The method according to claim 11, wherein after the completion of the polymer modification reaction, volatile components in the reactor are removed, and then the target product is discharged from the reactor.