JP4583391B2 - Process for producing hydrogenated olefinic polymer - Google Patents

Description

  The present invention relates to reaction control of a polymer solution or other organic compound solution, and relates to a measuring method and control of reaction state or reaction efficiency. More specifically, the present invention relates to a method for measuring the amount of transmission or reflection in the visible light region or the absorbance of a polymer solution or other organic compound solution, and reaction control from numerical values obtained from the above measurement method.

  Regarding reaction control of polymer solutions or other organic compound solutions, in recent years, in addition to indirect control of reaction conditions such as pressure, temperature, time, etc., the direct reaction feed composition and the composition of the reactor are analyzed, There are many methods for controlling the composition to a constant target value. Typical analysis methods are physical component separation methods such as gas chromatograph and liquid chromatograph, but in recent years there are problems such as long analysis time and long control cycle with respect to the factor fluctuation cycle of the reaction system. Infrared spectroscopy that can analyze multiple components simultaneously in about 1 minute (selection and application of process infrared analyzer: Proc Annu Symp Process ind vol 46th p99-112 etc.) Components by spectral separation such as near-infrared spectroscopy using absorption (JP-A-5-222178, JP-A-6-220162, JP-A-7-97420, JP-A-10-182802, etc.) Analytical techniques are becoming mainstream.

  However, the infrared or near-infrared spectroscopic analysis described above is a composition analysis method using molecular vibration of an organic functional group, and reaction control is performed from the composition value. In addition, in the infrared method, the absorption of organic substances is generally significant, the sample optical path length must be in the order of microns, pretreatment such as dilution is required, the equipment is expensive, and the analysis time is comparable to that of a chromatograph. There are many. In the near-infrared spectroscopic analysis, the cell length can be increased, but the measurement limit concentration is about 1% due to the overlap of the component attribution wavelength, and the value fluctuates due to the fluctuation of impurities. There are difficulties such as.

  On the other hand, in a reaction system or the like using a metal catalyst, color may be exhibited in the reaction process due to the interaction between the catalyst and the organic component. If the color reaction plays an important role in the rate-determining process of organic reaction, the absorption characteristics in the visible region control the reaction state more than the feed liquid composition and reactive organism composition analysis described above. It will be suitable to do. However, in the case of polymer solution and other organic compound solution reactions, there is no example of measuring the transmission or reflection spectrum in the visible region, and the fluctuation of the visible spectrum in the reaction process of the above solution is quantified to control the reaction. There have been no previous attempts.

  The object of the present invention is to provide a stable measurement technique for a transmission spectrum or a reflection spectrum in the visible light region upon reaction of a polymer solution or other organic compound solution, and to provide a technique for controlling the reaction from the spectrum. It is.

  In order to solve the above-mentioned problems, the present inventors have intensively studied on the effectiveness of measurement of a visible spectrum in the reaction process of a polymer solution and other organic compound solution and a means for stably measuring the visible spectrum. As a result, it was found that the reaction has coloration, and the reaction can be controlled by quantifying the visible spectrum or color when the coloration reaction affects the reaction rate-determining process. In addition, when measuring the visible spectrum or color using a measuring instrument, there is a measurement method that can eliminate disturbances due to scattering and absorption by foreign matter such as dirt and bubbles in the optical cell, which is always a problem in terms of accuracy and stability of optical measurement. The headline, the present invention has been reached.

Furthermore, the present invention includes the inventions of the following items.
1) Quantification of the visible spectrum and clarification of the correlation between the numerical variation and the process response factor.
2) Invention of quantification of visible spectrum, operation factor and control method.

That is, the present invention is achieved by the following method.
(1) In a reaction in a polymer solution or other organic compound solution, a spectrum or color obtained by a transmission method or a reflection method in the visible light region that changes with the reaction is measured, the spectrum or color is quantified, and the reaction is performed. How to control.
(2) In the spectrum or color measurement of (1), the predetermined total measurement range is divided into two or more areas, and the transmission amount or reflection amount, or the transmission brightness or reflection brightness in each area is obtained. (1) characterized in that an area outside a predetermined limit value is removed and average spectrum measurement is performed in the remaining area, or the average color of the remaining area is displayed in various color systems. How to control the reaction.

(3) In quantifying the spectrum or color of (1), quantifying the spectrum by transmission or reflection or absorbance of one or more wavelengths that change with the response of the spectrum, or obtaining a color difference, Alternatively, it is expressed as a vector on the color space, and the difference between the vector and a predetermined reference material vector is obtained, or a numerical value is obtained by using one or more orthogonal projection sizes on the color space of the vector. The method for controlling the reaction according to (1) or (2), wherein
(4) The spectrum or the color is digitized, and the control factor is controlled by calculating the reaction factor from the measured value of the spectrum or the color value using the calibration formula of the spectrum or the color value and the reaction factor prepared in advance. A method for controlling the reaction according to any one of (1) to (3), which is characterized in that

(5) In the hydrogenation reaction of the olefinic polymer, using the method described in (1), the spectrum or color obtained by the transmission or reflection method in the visible light region of the olefinic polymer solution is measured. A method for producing a hydrogenated olefin polymer, characterized in that the color is digitized and the reaction is controlled.
(6) In the spectrum or color measurement described in (5), the predetermined total measurement range is divided into two or more areas, and the transmission amount or reflection amount, or transmission brightness or reflection brightness in each area is measured. And removing an area outside a predetermined limit value and measuring an average spectrum in the remaining area, or displaying an average color of the remaining area in various color systems (5) A process for producing a hydrogenated olefin polymer as described in 1.

(7) In quantifying the spectrum or color described in (5) or (6), the spectrum is quantified by transmission or reflection or absorbance of one or more wavelengths that change with the reaction of the spectrum, Alternatively, the color difference is obtained or expressed as a vector on the color space, and the difference between the vector and the predetermined reference material vector is obtained, or the orthogonal projection size of the vector on the color space is calculated. The method for producing a hydrogenated olefinic polymer according to (5) or (6), wherein one or more are used for quantification.
(8) When a spectrum or color is digitized, a calibration formula of a spectrum or color value prepared in advance and an effective hydrogenation catalyst amount or a deactivated hydrogenation catalyst amount is used, and an actual measurement value of the spectrum or color value is used. The method for producing a hydrogenated olefin polymer according to any one of (5) to (7), wherein an effective hydrogenation catalyst amount is calculated.

(9) The method for producing a hydrogenated olefin polymer according to any one of (5) to (8), wherein the hydrogenation reaction is a homogeneous reaction using a metallocene compound as a catalyst.
(10) The hydrogenation reaction is a homogeneous reaction using a metallocene compound as a catalyst, and the transmittance or reflectance of an absorption band corresponding to an effective or deactivated hydrogenation catalyst in the range of 450 nm to 700 nm, or the amount of transmitted absorption or reflection. The method for producing a hydrogenated olefinic polymer according to any one of (5) to (9), wherein an absorption amount is determined.

  According to the method of the present invention, the hydrogenation reaction of a conjugated diene polymer can be maintained at a high hydrogenation rate even with a small amount of hydrogenation catalyst by adopting an automatic spectrum measurement method and an automatic control method.

The present invention will be specifically described below.
The polymer solution or other organic compound solution of the present invention has coloration in the visible light region in the reaction process, and is applied to any reaction when the coloration reaction affects the reaction rate-determining process.
Examples of the reaction of the polymer solution in the present invention include reactions such as a polymerization reaction, a terminal reaction of the polymer, and a hydrogenation reaction. In the reaction of the polymer solution, it is preferably used for the hydrogenation reaction of an olefin polymer having a double bond in the molecule.
As a method for measuring a spectrum or color, a method of providing a transparent window in a reactor, a method of providing a cell in a flow path, a fiberscope, or the like can be used.

For measuring the spectrum or color, a measuring instrument such as a visible spectrum meter, a camera-type spectrum meter, or a color camera can be used.
As a method for digitizing the spectrum, it can be obtained from the transmission absorption amount, the reflection absorption amount, the transmission brightness, or the reflection brightness. As a method for digitizing the color, any conventionally known method such as a method using an L ^* a ^* b ^* color system, a method using an XYZ color system, a method using an RGB color system, or the like may be used.
In the present invention, preferably, in the measurement of spectrum or color, the predetermined entire measurement range is divided into two or more areas, and the respective transmission amount or reflection amount, transmission lightness or reflection lightness in each area is obtained. Remove areas that deviate from the predetermined limits, or even include a predetermined number of areas adjacent to the area, and measure the average spectrum in the remaining areas, or change the average color of the remaining areas This is a method of controlling reaction by digitizing a spectrum or color obtained by a method of displaying in various color systems.

  The spectrum or color measurement method in the present invention is preferably an on-line continuous visible spectrum or color measurement. Here, as a method for obtaining a stable measurement value, the transmission amount or the reflection amount, or the transmission brightness or the reflection brightness may be a transmittance or a reflectance normalized by the transmission amount or the reflection amount of the standard substance. . Further, the absorbance calculated from the transmittance and the reflectance may be used.

  The area division is to divide the measurement visual field into a plurality of areas, and equal division is desirable, and more divided areas are more desirable. Usually, although it depends on the performance of the camera, it is preferably divided into 10 to 10,000 areas. In addition to the average value and integrated value of all wavelengths, the transmitted and reflected amounts of each area include the specific wavelength, specific wavelength band, the average or integrated value of multiple specific wavelengths and wavelength bands, or the important wavelength for measurement. It is also possible to use a weighted average weighted.

  When removing an area that deviates from the predetermined limit value, the predetermined limit value, that is, the threshold value, is determined in advance as the upper limit value and / or the lower limit value as absolute values, or all the values of each of the above divided areas The average value of each value is calculated, the deviation value from the average value for each area is calculated, and the deviation value exceeds the predetermined upper limit value and / or lower limit value. The average value and dispersion value of the optical quantity calculated from the above-mentioned optical measurement quantity or the quantity of the area may be obtained, and the dispersion value or a predetermined coefficient multiple of the square root thereof may be selected from the average value as the upper and lower thresholds. When an area outside the predetermined limit value is removed, the area can be removed so as to include a predetermined number of areas adjacent to the area. The predetermined number of adjacent areas can be, for example, from two areas, one area on each side, to eight areas surrounding the periphery, and further to the outer 24 areas, and a plurality of areas as one group, of which A method of removing an area group when one area is out of the limit value is also possible.

In the present invention, preferably, when the spectrum or color is digitized, the spectrum is digitized by the transmission amount or reflection amount or absorbance of a specific wavelength that changes with the reaction, the color difference is obtained, or the color space is obtained. And calculating the difference between the vector and a predetermined reference material vector, or by using one or more projections in the color space of the vector. .
As a method for digitizing the color, it is expressed as a vector on the color orthogonal coordinates such as the method using the L ^* a ^* b ^* color system, the method using the XYZ color system, the method using the RGB color system, and the like. Select the color display method that has the highest correlation with the change due to the reaction, based on the difference in size from the vector in the color space, etc., with the standard color as the color of a stable substance with no orthographic value or color change. Can do.

  In the present invention, preferably, when the spectrum or color is digitized, the spectrum or color is digitized using only the empty cell or solvent, and this is used as a standard spectral image, and the spectrum or color in the dark state is numeric. And can be quantified stably as a dark current spectrum image. In this case, it is also effective to digitize the method by removing an area that deviates from a predetermined limit value.

The numerical processing in the present invention is preferably performed by the following method.
(Transmittance of each wavelength in each area) = ((sample solution spectral image luminance value−dark current spectral image luminance value) / (standard spectral image luminance value−dark current spectral image luminance value))
In this processing method, the measurement system is calibrated by using the standard spectrum image and the dark current spectrum image, and it is possible to remove the influence of illumination, camera temperature drift, and the like when measuring the transmittance of the sample solution. This calibration is preferably performed for each measurement. However, when the temperature change in the environment where the camera is placed is small, there is no problem in accuracy even for several hours to once a day.

In the present invention, preferably, a spectrum or a color is digitized, and a calibration formula of a spectrum or color prepared in advance and a reaction factor (such as an effective catalyst amount, a deactivated catalyst amount) is used to calculate the spectrum or color value. It is a method for controlling a reaction characterized by calculating a reaction factor from an actual measurement value and controlling a control factor (such as a raw material composition, a catalyst amount, and a temperature).
The reaction factor is a specific factor related to the reaction rate-limiting process, and there are various cases such as an effective catalyst amount, that is, an active site amount, a deactivation catalyst amount, a reaction intermediate, and a product.
The operating factor is a specific factor that affects the increase or decrease of the reaction factor, and is an input added from the outside such as a raw material composition, a catalyst amount, and a temperature.

In the hydrogenation reaction of the olefin polymer, the present invention preferably measures the spectrum or color obtained by the transmission or reflection method in the visible light region of the olefin polymer solution, quantifies the spectrum or color, It is a method to control.
In the present invention, the olefin polymer is a polymer having a double bond in the molecule, such as a polymer of a conjugated diene, a copolymer with a monomer copolymerizable with the conjugated diene, a norbornene compound, etc. Polymers obtained by ring-opening polymerization of cycloolefin and derivatives thereof are included.
Polymers of the above conjugated dienes, and copolymers of monomers that can be copolymerized with conjugated dienes include those obtained by polymerizing using an organic alkali metal as a polymerization initiator, those obtained by polymerizing using a Ziegler catalyst as a polymerization initiator, and radicals. Including those polymerized using an initiator.

The olefin polymer in the present invention includes those having a reactive functional group at the terminal.
In the method for hydrogenating an olefin polymer in the present invention, hydrogen is supplied to a reactor supplied with an olefin polymer solution, the polymer solution and hydrogen are brought into contact with each other in the presence of a hydrogenation catalyst, This is a method in which a hydrogenation reaction is performed on a sex double bond.
As the hydrogenation catalyst, a Ziegler type hydrogenation catalyst using a transition metal salt such as nickel or cobalt and an organoaluminum reducing agent, or an organometallic complex such as titanium, ruthenium or rhodium is used.

In the present invention, preferably, when a spectrum or color is digitized, a numerical expression of the spectrum or color is used by using a calibration formula of a spectrum or color value prepared in advance and an effective hydrogenation catalyst amount or a deactivated hydrogenation catalyst amount. This is a method for producing a hydrogenated olefin polymer, characterized in that the amount of effective hydrogenation catalyst is calculated from the actual measured value. As a method for deriving the calibration formula, a method of introducing a regression analysis method based on a numerical value obtained experimentally in advance is preferably used.
One preferred method in the present invention may be a method in which the amount of the deactivated hydrogenation catalyst is once determined and the effective hydrogenation catalyst amount is calculated based on the numerical value.
The present invention is preferably a method for producing a hydrogenated olefin polymer in which the hydrogenation reaction is a homogeneous reaction using a metallocene compound as a catalyst.

One of the objects of the present invention is to achieve a sufficient hydrogenation rate under the condition that the feed amount of the hydrogenation catalyst is small in the production of the hydrogenated olefinic polymer.
As the metallocene compound, a metallocene compound such as titanium, zirconium or hafnium, or a reaction mixture of the metallocene compound and a reducing organic metal is used.
The present invention is preferably a homogeneous reaction in which the hydrogenation reaction uses a metallocene compound as a catalyst component, and the transmittance or reflectance of an absorption band corresponding to an effective or deactivated hydrogenation catalyst in the range of 450 nm to 700 nm, or This is a method for producing a hydrogenated olefinic polymer characterized in that a hydrogenation reaction is controlled by obtaining a transmission absorption amount or a reflection absorption amount and using the numerical value.

As a more preferred embodiment in the present invention, control of the hydrogenation reaction of a polymer or copolymer of a conjugated diene using an organic alkali metal compound as an initiator (hereinafter collectively referred to as a conjugated diene polymer). Is the method.
Here, the conjugated diene polymer is a conjugated diene polymer, a random or tapered or block copolymer of a conjugated diene and a vinyl aromatic compound, or a mixture containing these in an arbitrary ratio.
Examples of the conjugated diene include conjugated dienes having 4 to 20 carbon atoms, specifically 1,3-butadiene and isoprene. Examples of the vinyl aromatic compound include styrene, α-methylstyrene, p-methylstyrene, and the like.

In the present invention, when the conjugated diene polymer is a copolymer of a conjugated diene and a vinyl aromatic compound, the ratio of the conjugated diene and the vinyl aromatic compound contained in the polymer is 5/95 to 5/95. 95/5 is preferred. In the present invention, when the vinyl aromatic hydrocarbon content is less than 5% by weight, it is substantially regarded as a conjugated diene polymer.
The number average molecular weight of the conjugated diene polymer used in the present invention is preferably 10,000 to 3,000,000.
In the present invention, the molecular weight is measured by gel permeation chromatography (GPC), and the molecular weight of the chromatogram peak is a calibration curve obtained from the measurement of commercially available standard polystyrene (the peak molecular weight of standard polystyrene is used. )).

Moreover, the block copolymer of the conjugated diene and vinyl aromatic compound used in the present invention includes a block copolymer represented by any of the following general formulas and any mixture thereof.
(A-B) _n , A- (B-A) _n , B- (A-B) _n
[(BA) _{n] m + 1-} X, [(AB) _n ] _{m + 1-} X
[(B−A) _n −B] _{m + 1} −X, [(A−B) _n −A] _{m + 1} −X
(In the above formula, A is a polymer block mainly composed of vinyl aromatic hydrocarbon, and B is a polymer block mainly composed of conjugated diene. The boundary between the A block and the B block is not always clearly distinguished. In addition, n is 1 or more and is preferably an integer of 1 to 5. X is, for example, a polyvalent halogenated organosilicon compound, a polyvalent halogenated organotin compound, or a bifunctional to hexafunctional epoxy group. A residue of a coupling agent such as a compound or a residue of an initiator such as a polyfunctional organolithium compound, etc. m is 1 or more and preferably an integer of 1 to 10.

  The conjugated diene polymer can be obtained, for example, by polymerization in an inert hydrocarbon solvent using an organic alkali metal compound as a polymerization initiator. Suitable solvents are, for example, aliphatic hydrocarbons such as n-pentane and n-hexane, alicyclic hydrocarbons such as cyclohexane and cycloheptane, and aromatic hydrocarbons such as benzene and toluene.

  As the organic alkali metal compound used as the polymerization initiator of the conjugated diene polymer, an aliphatic hydrocarbon alkali metal compound or the like is used. Alkali metals include lithium, sodium, potassium and the like. Suitable organic alkali metal compounds are aliphatic or aromatic hydrocarbon lithium compounds having 1 to 20 carbon atoms, a compound containing one lithium in one molecule, a dilithium compound containing a plurality of lithium in one molecule, Trilithium compounds and tetralithium compounds are included. Specifically, n-, n-butyllithium, sec-butyllithium, tert-butyllithium, reaction product of diisopropenylbenzene and sec-butyllithium, divinylbenzene and sec-butyllithium and a small amount of 1,3 -Reaction products of butadiene and the like.

When producing a conjugated diene polymer by polymerizing a conjugated diene or a conjugated diene and a vinyl aromatic compound using an organic alkali metal compound as a polymerization initiator, the vinyl structure (1, 2 or 3, 4 bond) of the conjugated diene Tertiary amine compounds or ether compounds can be added to increase.
Examples of the tertiary amine compound include compounds of the general formula R 1 R 2 R 3 N (where R 1, R 2 and R 3 are hydrocarbon groups having 1 to 20 carbon atoms or a tertiary amino group). For example, trimethylamine, triethylamine, N, N, N ′, N′-tetramethylethylenediamine and the like.

The ether compound may be a linear ether compound or a cyclic ether compound. Examples of the linear ether compound include dimethyl ether and diethyl ether, and examples of the cyclic ether compound include tetrahydrofuran and dioxane.
The conjugated diene polymer can be obtained by either batch polymerization or continuous polymerization.
The conjugated diene polymer is preliminarily deactivated with a quenching agent before the hydrogenation from the point of suppressing the metallation reaction between polymer chains, which causes polymerization or gelation. It is preferable to keep it. Moreover, you may add the polyfunctional compound which has a 2 or more functional group in 1 molecule for the purpose of forming a branched or star-shaped polymer instead of deactivating.

  The quenching agent is not particularly limited, but those that react with an organometallic compound such as a hydroxyl group or a carbonyl group to produce an alkoxy metal, or those that produce a metal halide such as a halogen compound are preferred. In some cases, a compound having an ester group, a ketone group, an aldehyde group, an isocyanate group, an amino group, an imino group, or an acid anhydride group, a polyvalent epoxy compound, or a polyvalent halogen compound can also be used. These can be used for the purpose of reacting with the alkali metal terminal of the polymer to give a polar group to the polymer terminal, coupling it to increase the molecular weight, or generating a branch. Examples of the quenching agent include (polyhydric) alcohols, (polyhydric) phenols, organic carboxylic acids, etc., water, hydrogen, carbon dioxide gas, etc., and these may be used alone or in two types. You may mix above.

The solvent of the conjugated diene polymer solution in the hydrogenation reaction is an inert hydrocarbon solvent, and examples thereof include the same solvents that can be used for the polymerization of the conjugated diene polymer.
The concentration of the polymer in the conjugated diene polymer solution in the hydrogenation reaction is preferably 5 wt% or more from the viewpoint of energy load and production cost in the post-process for separating the hydrogenated polymer and the solvent. From the viewpoint of mixing with a hydrogenation catalyst or the like and heat transfer, 40 wt% or less is preferable.
The present invention is effective when a metallocene compound is used as a hydrogenation catalyst. The metallocene hydrogenation catalyst is an organometallic compound such as titanium, zirconium, hafnium or the like having two (substituted) cyclopentadienyl groups which are the same or different as a ligand, preferably a reducing organometallic compound, for example, Alkyl lithium, alkyl sodium, alkyl potassium, alkyl magnesium, alkyl aluminum and the like are used.

  Among metallocene hydrogenation catalysts, titanocene catalysts are preferable. As a hydrogenation method using a titanocene-based catalyst, for example, a method of hydrogenating an olefinic double bond in a polymer containing an olefinically unsaturated double bond with a Teve reagent which is a metallacycle compound of a titanocene compound and trimethylaluminum ( JP-A-11-71426), a method in which a titanocene compound is combined with a specified amount of lithium alkoxide to hydrogenate an olefinic double bond in an olefinically unsaturated double bond-containing polymer (JP-A-1 No. 275605) and the like, and the hydrogenation conditions can be a known method according to such a hydrogenation catalyst.

The hydrogenation reaction in the present invention may be performed by either a batch method or a continuous method.
The addition amount of the hydrogenation catalyst in the present invention is preferably from 0.001 mmol to 5 mmol per 100 g of the olefinically unsaturated group-containing polymer from the viewpoint of efficiently hydrogenating olefinically unsaturated groups. A more preferable catalyst addition amount is 0.002 milmol to 1 mmol per 100 g of the polymer.

The hydrogenation catalyst is generally fed to the reactor in the form of a solution. Any solvent may be used as long as it does not adversely affect the hydrogenation. For example, aliphatic hydrocarbons such as n-pentane and n-hexane, and alicyclic hydrocarbons such as cyclohexane and cycloheptane. Aromatic hydrocarbons such as benzene and toluene are used.
The hydrogenation catalyst may be supplied to the hydrogenation reactor separately from the olefinically unsaturated group-containing polymer solution, or the hydrogenation catalyst solution may be preliminarily stored in the olefinically unsaturated group-containing polymer solution or recycled hydrogen. It can also be fed to the reactor after mixing with the added polymer solution.

Hereinafter, the present invention will be described based on examples, but the present invention is not limited thereto.
A method for measuring physical properties of the conjugated diene polymer used in this example, and preparation examples of the conjugated diene polymer and the hydrogenation catalyst are shown below.
1) Measurement of physical properties of conjugated diene polymer 1-1) Styrene content: Calculated from absorption intensity at 262 nm using an ultraviolet spectrophotometer (UV2450, manufactured by Shimadzu Corporation).
1-2) Number average molecular weight: Measured by GPC (manufactured by Shimadzu Corporation, model LC-10AD), tetrahydrofuran was used as a solvent, and measurement conditions were performed at a temperature of 35 ° C. The molecular weight is a number average molecular weight obtained by using a calibration curve (created using the peak molecular weight of standard polystyrene) obtained by measuring the molecular weight of the peak of the chromatogram from measurement of commercially available standard polystyrene.
1-3) Vinyl bond and hydrogenation rate: Measured using a nuclear magnetic resonance apparatus (manufactured by BRUKER, DPX-400).

2) Preparation Example of Conjugated Diene Polymer An autoclave with a stirrer and a jacket was washed, dried, purged with nitrogen, and a cyclohexane solution containing 10 parts by mass of styrene purified in advance was added. Next, after adding n-butyllithium and tetramethylethylenediamine and polymerizing at 70 ° C. for 1 hour, a cyclohexane solution containing 80 parts by mass of pre-purified butadiene was added for 1 hour, and a cyclohexane solution containing 10 parts by mass of styrene was further added. For 1 hour. The resulting block copolymer was a block copolymer having a styrene content of 20 wt%, a 1,2-vinyl bond amount of polyptadiene part of 40 wt%, and a number average molecular weight of 100,000 (hereinafter referred to as conjugated diene polymer-1). Called).

3) Preparation example of hydrogenation catalyst The solution prepared by the following method was used for the hydrogenation catalyst.
Charge 1 liter of dried and purified cyclohexane to a nitrogen-substituted reaction vessel, add 100 mmol of bis (η5-cyclopentadienyl) titanium dichloride, and add n-hexane solution containing 200 mmol of trimethylaluminum with sufficient stirring. Then, the reaction was carried out at room temperature for about 3 days to obtain a TB reagent.

[Example 1]
1) After changing the amount of methanol added as a polymerization terminator to the conjugated diene polymer-1 solution to deactivate the living end, a certain amount of hydrogenation catalyst was added to conduct a hydrogenation reaction. It was observed that the polymer solution after the addition reaction had a dark color and almost no color. The relationship between the numerical value of the degree of color development and the hydrogenation rate 90 minutes after the start of the hydrogenation reaction of the olefinic double bond is shown.
Specifically, the polymer solution after completion of the hydrogenation reaction is sufficiently dried in advance, sampled in a liquid fixed cell substituted with an inert gas, and a typical table by a permeation method using cyclohexane used as a solvent as a standard color. The L ^* value of the L ^* a ^* b ^* color system, that is, the color system, that is, the lightness was digitized. At the same time, the hydrogenation rate of olefinic double bonds was measured.
FIG. 1 shows the relationship between the L ^* value (brightness) and the hydrogenation rate. From FIG. 1, it can be seen that in a state where the L ^* value is small (that is, the color is dark), the hydrogenation efficiency is low and the hydrogenation efficiency increases as the L ^* value increases.

2) After deactivating the living terminal under the condition that the amount of the polymerization terminator added to the solution of the conjugated diene polymer-1 is completely insufficient, hydrogenation is performed by changing the addition amount of the hydrogenation catalyst. The reaction was carried out, and the color of the polymer solution after completion of the hydrogenation reaction and the hydrogenation rate 60 minutes and 90 minutes after the start of the hydrogenation reaction of the olefinic double bond were measured in the same manner as in 1).
Table 1 shows the addition amount of the hydrogenation catalyst, L ^* value (lightness), and hydrogenation rate. The hydrogenation reaction under the condition that the amount of methanol in the polymerization terminator is insufficient will react if the addition amount of the hydrogenation catalyst is increased and the hydrogenation catalyst is deactivated during the reaction, and an appropriate amount of the polymerization terminator is not added. It turns out that is not completed.

FIG. 2 shows the relationship between the L ^* value (lightness) obtained from Table 1 and the amount of deactivated hydrogenation catalyst. From this figure, it can be seen that the decrease in the L ^* value corresponds to the amount of the hydrogenation catalyst deactivated due to the insufficient amount of the polymerization terminator. That is, when the L ^* value (lightness) is low, the polymerization terminator is in short supply, the amount of the deactivated hydrogenation catalyst increases according to the shortage of the polymerization terminator, and the activity of the hydrogenation catalyst decreases. It became clear that the hydrogenation efficiency was lowered.
Since the reaction activity in the hydrogenation reaction is determined by the effective hydrogenation catalyst amount obtained by subtracting the deactivated hydrogenation catalyst amount from the input hydrogenation catalyst amount, it is important to suppress the deactivation of the hydrogenation catalyst as much as possible.

3) A method of controlling the reaction by quantifying the color is shown.
When the L ^* value is measured from the above results and the value is larger than the predetermined value, the amount of the deactivated hydrogenation catalyst is minimized by feedback control for increasing the addition amount of the polymerization terminator by a predetermined amount. It is possible to keep the activity to the maximum.
As an example of reaction control, the L ^* value (lightness) is about 95 and the deactivated hydrogenation catalyst amount is almost zero from the relationship diagram between the L ^* value (lightness) and the deactivated hydrogenation catalyst amount in FIG. However, since the L ^* value does not change near 95, there is a possibility that the polymerization terminator becomes excessive and the hydrogenation rate decreases, so the control target of the L ^* value was set to 94 in this example.

After adding methanol as a polymerization terminator to the solution of the conjugated diene polymer-1 to deactivate the living end, a certain amount of hydrogenation catalyst was added to conduct a hydrogenation reaction, and the same as 1) The L ^* value of the polymer solution after completion of the hydrogenation reaction measured by the method was about 91.
Next, the hydrogenation reaction was performed under the same conditions as described above except that the amount of the polymerization terminator charged was feedback-controlled, and the L ^* value of the polymer solution after the hydrogenation reaction measured by the same method as in 1) was 94. there were.
Further, the amount of polymerization stopper charged is feedback controlled, and the hydrogenation reaction is carried out under the same conditions as above except that the amount of addition of the hydrogenation catalyst is reduced by half. After completion of the hydrogenation reaction measured in the same manner as in 1) The L ^* value of the polymer solution was 94.

As described above, feedback control of the addition amount of the polymerization terminator so that the L ^* value becomes 94 makes it possible to maintain the same high hydrogenation rate as in the past with half the amount of the conventional hydrogenation catalyst. became.
Similar results were obtained when control was performed with a color difference other than the L ^* value.

[Example 2]
As a method for controlling the hydrogenation reaction of a conjugated diene polymer by quantifying the spectrum or color, a more effective method for quantifying the visible spectrum and an automatic control method will be described.
The spectroscope used in this example was performed using an inspector, which is a camera-type spectroscope provided by Kawatetsu Techno-Research.
This camera-type spectroscope divides the measurement unit into 480 areas and divides each area by 640 divisions between about 380 nm and 800 nm. The output is obtained as a 480 × 640 image of 480 area 640 wavelengths (hereinafter, this image is referred to as a spectral image), and the transmission intensity of each wavelength in each area is output as luminance.

FIG. 3 shows an example of the measurement system and apparatus configuration.
In the measurement system, 2 is a light source, 3 is an optical fiber for irradiation, 4 is an optical fiber probe, and 5 is a sample cell. The light that has passed through the sample cell is received by the optical fiber probe on the light receiving side 4, the received light is transmitted by the imaging optical fiber 6 for light reception, and is split by the spectroscope 1.
In order to stabilize the measurement, first, the standard transmission amount is measured in a state where the cell is empty. Depending on the case, it is good also as a standard permeation | transmission amount, measuring in the state which filled the solvent etc. in the cell. In this case, there is no particular limitation as long as it is transparent or stable in color. After completing the acquisition of the standard spectrum image by the computer 10, the camera shutter 7 is closed to calibrate the temperature drift of the camera, and the spectrum image in that state (hereinafter referred to as a dark current spectrum image) is acquired. When a dark current spectrum image acquisition completion signal is sent to 10 computers, the valve 8 is automatically operated, the polymer solution is flowed from the reactor 9 into the measurement cell 5, and in the same manner as the standard solution measurement, A sample solution spectral image is acquired.

The transmittance of each wavelength of 480 areas was calculated from the measured three spectral images, that is, the standard spectral image, dark current spectral image, and sample solution spectral image by the following processing method. Further, calibration using the standard spectrum image and dark current spectrum image was performed every time the sample was measured.
(Transmittance of each wavelength in each area) = ((sample solution spectral image luminance value−dark current spectral image luminance value) / (standard spectral image luminance value−dark current spectral image luminance value))

Next, a method for calculating the absorbance spectrum of the sample solution from the transmittance of each wavelength in the 480 area will be described.
When the spectrum is measured, in some cases, bubbles or foreign substances may be mixed in the sample solution filled in the cell. In order to remove this influence, the following image processing was performed as preprocessing.
FIG. 4 is an example of a polymer solution spectrum image. The vertical axis indicates the measurement position, and the measurement is divided into 480 areas. The horizontal axis indicates the wavelength axis, and the visible transmitted light is divided into 640 wavelengths for each of the 480 areas, and the transmission intensity of each area and each wavelength is represented by luminance (brightness).
When foreign matters such as bubbles are present during measurement, they appear as black lines throughout the wavelength direction due to scattering, as shown in FIG. This black foreign matter portion is previously removed from the measurement range by image processing. The removal method may be removed directly by binarization processing from FIG. 4, but the following processing method stabilizes the data.

First, the transmittance or L ^* value (brightness) is measured for each of the areas obtained by further dividing the 480 area obtained by dividing the measurement position into 640 wavelengths on the wavelength axis.
Next, the average transmittance value or average L ^* value of the position-divided 480 areas is obtained for each area divided and spectrally divided into 640 wavelengths on the wavelength axis.
FIG. 5 shows the average transmittance of all the position-division areas obtained by processing FIG. 4 by the above method and the transmittance of each area.
A threshold is set between ± 3% of the average transmittance of all divided areas, and the remaining area is removed by adding the data of the position area that is above the upper threshold and below the lower threshold and the five areas on both sides of the area. The transmittance was recalculated. At that time, the same area was removed from the standard spectrum image and dark current spectrum image.

The recalculated transmittance is converted into absorbance (-log [transmittance]) and averaged for each wavelength in the wavelength direction to obtain a spectrum of the solution itself free from bubbles and foreign matters. As an order of processing, the transmittance can be converted into an absorbance spectrum after area average.
The Example which controlled hydrogenation reaction using the said visible spectrum meter is shown.
FIG. 6 shows an example of measurement of the visible spectrum. FIG. 6 shows that the hydrogenation reaction is started from a state in which a predetermined amount of hydrogenation catalyst is added to the conjugated diene polymer-1 and the polymerization terminator is artificially insufficient, and the addition amount of the polymerization terminator is gradually increased. The change in the visible spectrum of the polymer solution was shown.

Although an absorption peak is observed in the vicinity of 570 nm, the absorption of the peak decreases as the addition amount of the polymerization terminator is increased. From this, it can be seen that the absorption peak at 570 nm corresponds to the amount of the hydrogenation catalyst deactivated due to insufficient polymerization terminator. For the absorbance at 570 nm, which is the control value, a value obtained by baseline-correcting the absorbance at 570 nm with the absorbance at 750 nm was adopted.
Next, the addition amount of the hydrogenation catalyst was changed, and the addition amount of the polymerization terminator was changed under each condition to perform a hydrogenation reaction, and the visible spectrum of the polymer solution and the hydrogenation rate were measured. As a result, as shown in FIG. 7, the value obtained by dividing the absorbance at 570 nm with respect to the hydrogenation rate by the amount of hydrogenation catalyst (hereinafter referred to as P value) has a convex relationship upward and is 0.0006. The maximum hydrogenation rate was shown, and this value was taken as the control target value (Pv value).

The excess and deficiency of the polymerization terminator, which is an operating factor, can also be arranged by the P value, and has the relationship shown in FIG. Although FIG. 7 is theoretically assumed to be a parabolic curve, only the linear portion near the equivalence point is actually used.
An automatic control method using the correlation diagrams of FIGS. 7 and 8 will be described.
FIG. 9 shows an example of the control block. As a control flow, (1) the visible spectrum of the polymer solution in the hydrogenation reactor is measured to determine the absorbance at 570 nm. (2) The P value is calculated from the absorbance at 570 nm. At that time, the concentration of the hydrogenation catalyst, which is the denominator of the P value, is obtained by an approximate calculation using a temporary delay system from the operation history of the addition amount of the hydrogenation catalyst. (3) The deviation between the obtained P value and the control target value (Pv value) is obtained using the correlation diagrams of FIGS. 7 and 8, and the excess and deficiency of the polymerization terminator as the operation factor is calculated. (4) The amount of operation of the polymerization terminator is feedback controlled. (5) (1) Measure the visible spectrum in the hydrogenation reactor. Responds to fluctuations due to disturbances, such as the amount of polymerization initiation catalyst added and the amount of impurities.

It is a figure showing the relationship between the L ^* value (lightness) and hydrogenation rate in Example 1. FIG. 3 is a diagram illustrating a relationship between an L ^* value (lightness) and an amount of deactivated hydrogenation catalyst in Example 1. 6 is a conceptual diagram of a measurement system and a device configuration in Example 2. FIG. 2 is an example of a polymer solution spectrum diagram in Example 2. FIG. It is a figure showing the relationship between the average transmittance | permeability of a position division all area, and the transmittance | permeability of each area. 3 is a measurement example of a purple spectrum in Example 2. It is a figure showing the relationship between P value and hydrogenation amount. It is a figure showing the relationship between the amount of operating factors excess and deficiency, and P value. It is a conceptual diagram which shows an example of a control block.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Spectrometer 2 Light source 3 Optical fiber for illumination 4 Optical fiber probe 5 Sample cell 6 Imaging optical fiber for light reception 7 Camera shutter 8 Valve 9 Reactor 10 Computer

Claims (4)

A method for producing a hydrogenated olefinic polymer, wherein a predetermined total measurement range is divided into two or more areas in a hydrogenation reaction of an olefinic polymer, and the amount of transmission or reflection in each area. Alternatively, a process for obtaining a hydrogenated olefin polymer, comprising the steps of obtaining transmitted light intensity or reflected light intensity, removing an area outside a predetermined limit value, and measuring an average spectrum in the remaining area to control the reaction. Method. A method for producing a hydrogenated olefinic polymer, wherein a predetermined total measurement range is divided into two or more areas in a hydrogenation reaction of an olefinic polymer, and the amount of transmission or reflection in each area. Alternatively, the method includes a step of obtaining a transmission lightness or a reflection lightness, removing an area outside a predetermined limit value, and displaying an average color of the remaining area in various color systems to control a reaction. A method for producing an added olefinic polymer. The method for producing a hydrogenated olefin polymer according to claim 1 or 2, wherein the hydrogenation reaction is a homogeneous reaction using a metallocene compound as a catalyst. The hydrogenation reaction is a homogeneous reaction using a metallocene compound as a catalyst, and the transmittance or reflectance of an absorption band corresponding to an effective or deactivated hydrogenation catalyst in the range of 450 nm to 700 nm, or the transmission absorption amount or reflection absorption amount. The method for producing a hydrogenated olefinic polymer according to any one of claims 1 to 3, which is obtained.

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