JP4221886B2 - Living radical polymerization initiator system and polymer production method using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a living radical polymerization initiator system and a method for producing a polymer using the same. More specifically, the present invention relates to a living radical polymerization initiator system that can be applied in a wide range with respect to the types and combinations of radical polymerizable monomers, and further uses the living radical polymerization initiator system to control the molecular weight. The present invention also relates to a method for producing a polymer having a narrow molecular weight distribution easily and at a higher speed than in the past.
[0002]
[Prior art]
According to living polymerization, a polymer can be produced while controlling the molecular weight, molecular weight distribution, terminal structure and the like. For example, when living polymerization is applied to anionic polymerization, coordinated anionic polymerization, or cationic polymerization, a block polymer or a terminal functionalized polymer with a controlled degree of polymerization can be produced. However, the monomers applicable to anionic polymerization, coordinated anionic polymerization or cationic polymerization itself are limited to specific ones compared to a wide variety of monomers applicable to radical polymerization. There is a problem that the application range of living polymerization to coordination anionic polymerization or cationic polymerization is necessarily narrow.
[0003]
On the other hand, the application of living polymerization to radical polymerization, which can be applied to a wide range of monomers, has been considered difficult because it tends to cause side reactions such as polymerization termination and chain transfer at the growth end. Living polymerization in a broad sense using the equilibrium reaction between activated and activated materials has become possible. Examples thereof include those using radical scavengers such as nitroxide compounds (Macromolecules, vol. 27, 7228 (1994)), those using an initiator system in which an organic halide and a transition metal complex are combined, and the like.
[0004]
In particular, those using an initiator system in which an organic halide and a transition metal complex are combined are useful in that they can be applied to a wide range of monomers, a polymerization temperature that can be applied to existing equipment, and the like. Specifically, a transition metal complex such as dichlorotris (triphenylphosphine) ruthenium, an organic halogen compound (polymerization initiator) such as carbon tetrachloride, 1-phenylethyl chloride or ethyl-2-bromoisobutyrate, The one using a polymerization initiator system (living radical polymerization initiator system) composed of a Lewis acid such as an aluminum alkoxy compound has been proposed (Macromolecules, vol. 28, 1721 (1995); J. Am. Chem. Soc 117, 5614 (1995); JP-A-8-41117; JP-A-9-208616, etc.).
[0005]
[Problems to be solved by the invention]
However, when performing radical polymerization using a living radical polymerization initiator system as described above, which is a combination of an organic halide and a transition metal complex, according to the knowledge obtained by the present inventors, the expected polymerization In order to obtain the result, there is a problem that the central metal or ligand of the transition metal complex must be changed according to the type of monomer to be subjected to living radical polymerization. Therefore, it is substantially difficult to apply one living radical polymerization initiator system to a wide range of monomers or to copolymerization using two or more monomers.
[0006]
In addition, in order to control the molecular weight and molecular weight distribution at a high level while suppressing side reactions such as polymerization termination and chain transfer at the growth end depending on the reactivity of the monomer, an initiator system with a very slow polymerization is used. Depending on the monomer, it may be difficult to produce the polymer in a practical time.
[0007]
The present invention is capable of easily producing a radical polymer having a narrow molecular weight distribution while controlling the molecular weight and at a higher speed than the conventional one, and initiating living radical polymerization applicable to a wide range of types and combinations of radical polymerizable monomers. An object is to provide an agent system.
[0008]
[Means for Solving the Problems]
The inventors select a specific ruthenium complex as the transition metal complex, and combine the specific ruthenium complex with a specific organic halide and a specific activator to form a living radical polymerization initiator system as described above. The inventors have found that the above problem can be solved, and have completed the present invention.
[0009]
That is, the present invention includes the following components (A), (B) and (C):
(A) halogenopentamethylcyclopentadienylbis (triarylphosphine) ruthenium;
(B) an α-halogenocarbonyl compound or an α-halogenocarboxylic acid ester;
as well as
(C) Amine
It is a living radical polymerization initiator system characterized by comprising.
[0010]
The present invention also provides a method for producing a polymer, characterized in that at least one radical polymerizable monomer is subjected to living radical polymerization in the presence of the above-described living radical polymerization initiator system.
[0011]
In this production method, when at least two kinds of radical polymerizable monomers are used as the radical polymerizable monomer, the resulting polymer is a copolymer.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
[0013]
The living radical polymerization initiator system of the present invention uses halogenopentamethylcyclopentadienylbis (triarylphosphine) ruthenium as a transition metal complex (component (A)) and an organic halide (polymerization initiator (component (B )) Is used as an α-halogenocarbonyl compound or α-halogenocarboxylic acid ester, and an amine (component (C)) is used as an activator.
[0014]
In the present invention, halogenopentamethylcyclopentadienylbis (triarylphosphine) ruthenium is used as the transition metal complex of component (A), but pentamethylcyclopenta which is one of the ligands for ruthenium as the central metal. When the dienyl group is replaced with another coordinating group (for example, a cyclopentadienyl group), the effects of the present invention are not sufficiently achieved. The reason is that pentamethylcyclopentadienyl is an appropriate electron donating group, so that a transition metal complex having it as one of the ligands has an appropriate redox ability, and as a result, a polymerization initiator and This may be because the equilibrium reaction between the structure having a carbon-halogen bond at the growth terminal of the polymer and the structure of the carbon radical formed by radical dissociation of the structure by a transition metal complex can be efficiently activated. Presumed.
[0015]
Preferable specific examples of component (A) include chloropentamethylcyclopentadienylbis (triarylphosphine) ruthenium such as chloropentamethylcyclopentadienylbis (triphenylphosphine) ruthenium.
[0016]
In the living radical polymerization initiator system of the present invention, the α-halogenocarbonyl compound or α-halogenocarboxylic acid ester of component (B) is used as the polymerization initiator.
[0017]
When component (B) is an α-halogenocarbonyl compound, preferred specific examples thereof include 2,2-dichloroacetophenone and 1,1-dichloroacetone. When component (B) is an α-halogenocarboxylic acid ester, preferred specific examples thereof include ethyl 2-bromo-2-methylpropanoate, dimethyl 2-chloro-2,4,4-trimethylglutarate, 1, 2-bis (α-bromopropionyloxy) ethane and the like can be mentioned.
[0018]
In the living radical polymerization initiator system of the present invention, the component (C) amine is used as an activator. Examples of such amines include aliphatic primary amines such as methylamine, ethylamine, propylamine, isopropylamine, and butylamine, and aliphatic secondary amines such as dimethylamine, diethylamine, dipropylamine, diisopropylamine, and dibutylamine. , Aliphatic amines such as aliphatic tertiary amines such as trimethylamine, triethylamine, tripropylamine, triisopropylamine, tributylamine; N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, Aliphatic polyamines such as N ″, N ″ -pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetraamine; aromatic primary amines such as aniline and toluidine, diphenylamine, etc. Aromatic secondary amine, triphenylamine And aromatic amines such as aromatic tertiary amines. Of these, aliphatic amines are preferable, and butylamine, dibutylamine, tributylamine and the like are particularly preferable.
[0019]
The content ratio of each component in the living radical polymerization initiator system of the present invention is not necessarily limited, but if the ratio of the component (A) to the component (B) is too low, the polymerization tends to be slow, On the other hand, if the molecular weight distribution of the resulting polymer tends to be wide if it is too high, the molar ratio of component (A): component (B) is preferably in the range of 0.05: 1 to 1: 1. . On the other hand, if the ratio of the component (C) to the component (B) is too low, the polymerization is slowed. Conversely, if the ratio is too high, the molecular weight distribution of the resulting polymer tends to be widened. The molar ratio of C) is preferably in the range of 1: 1 to 1:10.
[0020]
In the living radical polymerization initiator system of the present invention, the transition metal complex of component (A), the polymerization initiator of component (B), and the activator of component (C) are usually mixed immediately before use. Can be manufactured. In addition, the transition metal complex of component (A), the polymerization initiator of component (B), and the activator of component (C) are stored separately, and added separately to the polymerization reaction system, and the polymerization reaction It may be mixed in the system so as to function as a living radical polymerization initiator system.
[0021]
Next, a method for producing a polymer (including a copolymer) using the living radical polymerization initiator system of the present invention will be described.
[0022]
This production method basically involves living polymerizing a radical polymerizable monomer in a solvent such as toluene in the presence of the living radical polymerization initiator system of the present invention. Thereby, the number average molecular weight (Mn) of the obtained polymer can be increased almost in proportion to the increase in the polymerization rate, and the molecular weight distribution represented by weight average molecular weight / number average molecular weight (Mw / Mn). Can be a value close to 1. Therefore, at the time of the progress of the polymerization, the production of the polymer due to the chain termination or the transfer reaction can be suppressed to allow the living polymerization to proceed. Furthermore, even when two or more types of monomers are combined and random copolymerization is performed, the molecular weight can be controlled and the molecular weight distribution can be made close to 1. In addition, a polymerization reaction system in which the polymerization of one type of monomer or a mixture of two or more types of monomers is almost completed as the first step, and a new type of monomer or two or more types of single units are added as the second step. If the monomer mixture is added, the number average molecular weight can be increased while maintaining the molecular weight distribution close to 1, and a block copolymer can be produced. Then, in the same way, in the third stage or higher, add one monomer or a mixture of two or more monomers to produce a triblock or higher multiblock copolymer. can do.
[0023]
As the radical polymerizable monomer used in the living radical polymerization reaction according to the production method of the present invention, from the viewpoint of versatility and the remarkable effect of the present invention, from a styrene monomer, a methacrylic ester and an acrylic ester. At least one radically polymerizable monomer selected from the group consisting of Examples of the styrene monomer include styrene, p-methyl styrene, p-methoxy styrene, pt-butyl styrene, pn-butyl styrene, p-chlorostyrene and the like, and a particularly preferable example is styrene. . Examples of the methacrylic acid ester include methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate and the like, and particularly preferred examples include methyl methacrylate and butyl methacrylate. Examples of the acrylate ester include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and the like, and particularly preferred examples include methyl acrylate and butyl acrylate. In addition, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylic amide, N-substituted (meth) acrylic amide, acrylonitrile, methacrylonitrile, fumaric anhydride, fumaric acid Radical polymerizable monomers such as methyl and ethyl fumarate can be used. The above “(meth) acrylic acid” is a general term for “methacrylic acid” and “acrylic acid”.
[0024]
In the production method of the present invention, the initial concentration of the radically polymerizable monomer in the polymerization reaction system is not necessarily limited, but if it is too low, the reaction is too slow, and if it is too high, the radical of the generated radical is converted into the monomer. Since the chain transfer reaction is increased and the molecular weight distribution of the resulting polymer is widened, the range is preferably 0.5 to 8 mol (mol) / L (liter), and particularly preferably 1 to 4 mol / L. The concentration of each component in the polymerization system at that time is not necessarily limited, but the concentration of the polymerization initiator of component (B) is preferably 0, although there is a difference depending on the concentration of the radical polymerization monomer. .1 to 100 mmol (mmol) / L (liter), particularly preferably 0.5 to 50 mmol / L. The concentration of the transition metal complex of component (A) is preferably 0.1 to 50 mmol / L, particularly preferably 0.5 to 10 mmol / L. The concentration of the component (C) amine is preferably 1 to 200 mmol / L, particularly preferably 10 to 50 mmol / L.
[0025]
In the production method of the present invention, at the start of the living radical polymerization reaction, a monomer, a solvent, an amine (component (C)) and a transition metal complex (component (component (C)) are placed in a reaction vessel under an inert gas atmosphere such as nitrogen. It is preferable to prepare a mixture comprising A)) and add a polymerization initiator (component (B)) thereto. Polymerization can be initiated by heating the mixture thus obtained to a temperature in the range of 60 to 120 ° C., for example.
[0026]
After completion of the polymerization reaction, for example, the polymerization reaction system is cooled to 0 ° C. or less, preferably about −78 ° C. to stop the reaction, and then the reaction mixture is diluted with an organic solvent such as toluene, and the polymerization initiator is diluted with dilute hydrochloric acid. After removing the metal component of the system, the polymer can be obtained by evaporating volatile components.
[0027]
【Example】
Hereinafter, the present invention will be specifically described by way of examples.
[0028]
In the following examples and comparative examples, unless otherwise specified, all operations were performed in a dry nitrogen gas atmosphere, and the reagents were collected from the container with a syringe and added to the reaction system. Further, the solvent and the monomer were purified by distillation and further used after blowing dry nitrogen gas.
[0029]
The polymerization rate of the polymer was calculated based on the analysis value obtained by analyzing the monomer concentration in the reaction mixture by gas chromatography (internal standard substance: n-octane).
[0030]
The number average molecular weight (Mn), the weight average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) of the obtained polymer are as follows using gel permeation chromatography (GPC). Measured, polymethyl methacrylate, polymethyl acrylate and poly (methyl methacrylate-methyl acrylate) random copolymer were calculated in terms of polymethyl methacrylate, and polystyrene was calculated in terms of polystyrene.
Column: Shodex K-805L (3 in series)
Solvent: Chloroform
Temperature: 40 ° C
Detector: RI and UV
Flow rate: 1 ml / min
[0031]
Example 1
4.28 ml (40.1 mmol) of methyl methacrylate, 3.57 ml of toluene and 0.856 ml of n-octane were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 0.800 ml (0.401 mmol) of a 500 mmol / L toluene solution of dibutylamine, and then 31.9 mg (0.0401 mmol) of chloropentamethylcyclopentadienylbis (triphenylphosphine) ruthenium was added at room temperature. And finally, 0.499 ml (0.401 mmol) of a 802 mmol / L toluene solution of dimethyl 2-chloro-2,4,4-trimethylglutarate was added. The resulting mixture was heated to 80 ° C. to initiate the polymerization reaction.
[0032]
When 6 hours had elapsed after the start of the polymerization reaction, the reaction mixture was cooled to −78 ° C. to stop the polymerization reaction. The polymerization rate of methyl methacrylate is 31%, and the polymethyl methacrylate present in the reaction mixture has a number average molecular weight (Mn) of 3800 and a polymerization average molecular weight (Mw) of 4100. Therefore, Mw / Mn is 1.08. Furthermore, the GPC curve was unimodal.
[0033]
Example 2
In Example 1, the polymerization reaction was performed and analyzed in the same manner as in Example 1 except that the polymerization reaction was started and stopped after 50 hours. As a result, the polymerization rate of methyl methacrylate was 95%, Mn of polymethyl methacrylate present in the reaction system was 12700, Mw was 14900, Mw / Mn was 1.17, and the GPC curve was unimodal. It was.
[0034]
As apparent from a comparison of Example 2 with Example 1, when the polymerization rate is increased, the Mn of the resulting polymer increases in proportion to it, but the value of Mw / Mn is kept close to 1. You can see that it is leaning.
[0035]
Comparative Example 1
4.28 ml (40.1 mmol) of methyl methacrylate, 1.28 ml of toluene and 0.856 ml of n-octane were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 3.20 ml (0.401 mmol) of 125 mmol / L toluene solution of aluminum tri-t-butoxide, and then 191.8 mg (0.200 mmol) of dichlorotris (triphenylphosphine) ruthenium was added at room temperature. The mixture was stirred, and finally 0.389 ml (0.401 mmol) of a 1030 mmol / L toluene solution of dichloroacetophenone was added. The resulting mixture was heated to 80 ° C. to initiate the polymerization reaction.
[0036]
After 150 hours from the start of the polymerization reaction, the reaction mixture was cooled to −78 ° C. to stop the polymerization reaction. The polymerization rate of methyl methacrylate was 94%, and Mn of polymethyl methacrylate present in the reaction mixture was 9000, Mw was 12900, and thus Mw / Mn was 1.43.
[0037]
As is clear from comparison between Examples 1 and 2 and Comparative Example 1, when the initiator system of the present invention is used, dichlorotris (triphenylphosphine) ruthenium as a transition metal complex that is outside the scope of the present invention. It can be seen that the molecular weight distribution is narrower and the polymerization is faster than when aluminum tri-t-butoxide is used as the activator.
[0038]
Comparative Example 2
4.28 ml (40.1 mmol) of methyl methacrylate, 1.17 ml of toluene and 0.856 ml of n-octane were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 3.20 ml (0.401 mmol) of 125 mmol / L toluene solution of aluminum triisopropoxide, and then 31.9 mg (0.0401 mmol) of chloropentamethylcyclopentadienylbis (triphenylphosphine) ruthenium. The mixture was added at room temperature and stirred sufficiently. Finally, 0.499 ml (0.401 mmol) of a 802 mmol / L toluene solution of dimethyl 2-chloro-2,4,4-trimethylglutarate was added. The resulting mixture was heated to 80 ° C. to initiate the polymerization reaction.
[0039]
When 313 hours had elapsed after the start of the polymerization reaction, the reaction mixture was cooled to −78 ° C. to stop the polymerization reaction. The polymerization rate of methyl methacrylate is 92%, and the number average molecular weight (Mn) of polymethyl methacrylate present in the reaction mixture is 9600, and the polymerization average molecular weight (Mw) is 11200. Therefore, Mw / Mn is 1.17.
[0040]
As is clear from comparison between Example 2 and Comparative Example 2, when the initiator system of the present invention is used, when aluminum triisopropoxide is used as an activator that is outside the scope of the present invention. It can be seen that the polymerization is fast while controlling the molecular weight and molecular weight distribution.
[0041]
Example 3
Styrene 5.04 ml (44.0 mmol), toluene 3.52 ml and n-octane 1.01 ml were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 0.880 ml (0.440 mmol) of a 500 mmol / L toluene solution of dibutylamine, and then 35.0 mg (0.0440 mmol) of chloropentamethylcyclopentadienylbis (triphenylphosphine) ruthenium was added at room temperature. Finally, 0.549 ml (0.440 mmol) of a 802 mmol / L toluene solution of dimethyl 2-chloro-2,4,4-trimethylglutarate was added. The resulting mixture was heated to 100 ° C. to initiate the polymerization reaction.
[0042]
When 8 hours had elapsed after the start of the polymerization reaction, the reaction mixture was cooled to −78 ° C. to stop the polymerization reaction. The polymerization rate of styrene was 22%, and the Mn of polystyrene present in the reaction mixture was 2900, Mw was 3100, and thus Mw / Mn was 1.07. Furthermore, the GPC curve was unimodal.
[0043]
Example 4
In Example 3, the polymerization reaction was performed and analyzed in the same manner as in Example 3 except that the polymerization reaction was started and stopped after 51 hours. As a result, the polymerization rate of styrene was 91%, the Mn of polystyrene present in the reaction system was 11000, Mw was 12000, Mw / Mn was 1.09, and the GPC curve was unimodal.
[0044]
As is clear from the comparison of Example 4 with Example 3, when the polymerization rate is increased, the Mn of the obtained polymer increases in proportion to it, but the value of Mw / Mn is kept close to 1. You can see that it is leaning.
[0045]
Comparative Example 3
2.52 ml (22.0 mmol) of styrene, 4.24 ml of toluene and 0.504 ml of n-octane were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 3.52 ml (0.440 mmol) of 125 mmol / L toluene solution of aluminum triisopropoxide, and then 105.5 mg (0.110 mmol) of dichlorotris (triphenylphosphine) ruthenium was added at room temperature. The mixture was stirred, and finally 0.214 ml (0.220 mmol) of a 1030 mmol / L toluene solution of ethyl 2-bromo-2-methylpropanoate was added. The resulting mixture was heated to 100 ° C. to initiate the polymerization reaction.
[0046]
When 50 hours had passed since the polymerization reaction was started, the reaction mixture was cooled to −78 ° C. to stop the polymerization reaction. The polymerization rate of styrene was 90%, and the Mn of polystyrene present in the reaction mixture was 9500, Mw was 16800, and thus Mw / Mn was 1.77.
[0047]
As is clear from comparison between Examples 3 and 4 and Comparative Example 3, when the initiator system of the present invention is used, dichlorotris (triphenylphosphine) ruthenium as a transition metal complex that is outside the scope of the present invention. It can be seen that the molecular weight distribution is narrower than when aluminum triisopropoxide is used as the activator.
[0048]
Example 5
3.42 ml (38.0 mmol) of methyl acrylate, 4.27 ml of toluene, and 0.684 ml of n-octane were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 0.760 ml (0.380 mmol) of a 500 mmol / L toluene solution of dibutylamine, and then 30.3 mg (0.0381 mmol) of chloropentamethylcyclopentadienylbis (triphenylphosphine) ruthenium was added at room temperature. The mixture was sufficiently stirred, and finally 0.369 ml (0.380 mmol) of a 1030 mmol / L toluene solution of ethyl 2-bromo-2-methylpropanoate was added. The resulting mixture was heated to 80 ° C. to initiate the polymerization reaction.
[0049]
When 2 hours had elapsed after the start of the polymerization reaction, the reaction mixture was cooled to −78 ° C. to stop the polymerization reaction. The polymerization rate of methyl acrylate was 37%, and Mn of polymethyl acrylate present in the reaction mixture was 3100, Mw was 4000, and thus Mw / Mn was 1.29. Furthermore, the GPC curve was unimodal.
[0050]
Example 6
In Example 5, the polymerization reaction was performed and analyzed in the same manner as in Example 5 except that the polymerization reaction was started and stopped 24 hours later. As a result, the polymerization rate of methyl acrylate was 91%, Mn of polymethyl acrylate present in the reaction system was 8800, Mw was 11200, Mw / Mn was 1.27, and the GPC curve was unimodal. It was.
[0051]
As apparent from a comparison of Example 6 with Example 5, when the polymerization rate is increased, the Mn of the polymer obtained increases almost proportionally, but the value of Mw / Mn is kept close to 1. You can see that it is leaning.
[0052]
Comparative Example 4
1.71 ml (19.0 mmol) of methyl acrylate, 4.22 ml of toluene and 0.342 ml of n-octane were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 3.04 ml (0.380 mmol) of a 125 mmol / L toluene solution of aluminum triisopropoxide, and then 91.1 mg (0.0950 mmol) of dichlorotris (triphenylphosphine) ruthenium was added at room temperature. The mixture was stirred, and finally, 0.185 ml (0.190 mmol) of a 1030 mmol / L toluene solution of ethyl 2-bromo-2-methylpropanoate was added. The resulting mixture was heated to 80 ° C. to initiate the polymerization reaction.
[0053]
When 145 hours had elapsed after the start of the polymerization reaction, the polymerization reaction was stopped by cooling the reaction mixture to −78 ° C. The polymerization rate of methyl acrylate was 95%, and Mn of polymethyl acrylate present in the reaction mixture was 6800, Mw was 10900, and thus Mw / Mn was 1.60.
[0054]
As is clear from comparison between Examples 5 and 6 and Comparative Example 4, when the initiator system of the present invention is used, dichlorotris (triphenylphosphine) ruthenium as a transition metal complex that is outside the scope of the present invention. It can be seen that the molecular weight distribution is narrower and the polymerization is faster than when aluminum triisopropoxide is used as the activator.
[0055]
Example 7
3.21 ml (30.0 mmol) of methyl methacrylate, 2.70 ml (30.0 mmol) of methyl acrylate, 5.66 ml of toluene and 1.18 ml of n-octane were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 1.50 ml (0.600 mmol) of a 400 mmol / L toluene solution of tributylamine, and then 47.8 mg (0.0600 mmol) of chloropentamethylcyclopentadienylbis (triphenylphosphine) ruthenium was added at room temperature. Finally, 0.748 ml (0.600 mmol) of a 802 mmol / L toluene solution of dimethyl 2-chloro-2,4,4-trimethylglutarate was added. The resulting mixture was heated to 80 ° C. to initiate the polymerization reaction.
[0056]
After 59 hours from the start of the polymerization reaction, the reaction mixture was cooled to −78 ° C. to stop the polymerization reaction. The polymerization rates of methyl methacrylate and methyl acrylate are 90% and 59%, respectively. The Mn of the poly (methyl methacrylate-methyl acrylate) random copolymer present in the reaction mixture is 9000, and Mw is 10900 and thus Mw / Mn was 1.21.
[0057]
Comparative Example 5
2.14 ml (20.0 mmol) of methyl methacrylate, 1.80 ml (20.0 mmol) of methyl acrylate, 1.68 ml of toluene and 0.788 ml of n-octane were collected in a Schlenk reaction tube and mixed uniformly. To this mixed solution was added 3.20 ml (0.400 mmol) of a 125 mmol / L toluene solution of aluminum tri-t-butoxide, and then 192 mg (0.200 mmol) of dichlorotris (triphenylphosphine) ruthenium was added at room temperature and stirred sufficiently. Finally, 0.389 ml (0.400 mmol) of a 1030 mmol / L toluene solution of carbon tetrachloride was added. The resulting mixture was heated to 80 ° C. to initiate the polymerization reaction.
[0058]
After 180 hours from the start of the polymerization reaction, the reaction mixture was cooled to −78 ° C. to stop the polymerization reaction. The polymerization rates of methyl methacrylate and methyl acrylate are 92% and 77%, respectively, and the Mn of the poly (methyl methacrylate-methyl acrylate) random copolymer present in the reaction mixture is 6000, and Mw is 9500, and thus Mw / Mn was 1.58.
[0059]
As is clear from comparison between Example 7 and Comparative Example 5, when the initiator system of the present invention was used, dichlorotris (triphenylphosphine) ruthenium, an initiator as a transition metal complex outside the scope of the present invention. As compared with the case of using carbon tetrachloride and aluminum tri-t-butoxide as the activator, it can be seen that the molecular weight distribution of the random copolymer using a mixture of two kinds of monomers is narrow.
[0060]
【The invention's effect】
According to the living radical polymerization initiator system of the present invention, a wide variety of radical polymerizable monomers can be polymerized at a high speed while controlling the molecular weight, and a polymer having a narrow molecular weight distribution can be produced. It becomes. And when the living radical polymerization initiator system is applied to copolymerization of two or more types of radical polymerizable monomers, it can be copolymerized at high speed while controlling the molecular weight for a wide range of combinations of various monomers. In addition, a copolymer having a narrow molecular weight distribution can be produced.

Claims (7)

The following components (A), (B) and (C):
(A) halogenopentamethylcyclopentadienylbis (triarylphosphine) ruthenium;
(B) an α-halogenocarbonyl compound or an α-halogenocarboxylic acid ester;
And (C) a living radical polymerization initiator system comprising an amine. The living radical polymerization initiator system according to claim 1, wherein the component (A) is chloropentamethylcyclopentadienylbis (triarylphosphine) ruthenium. The living radical polymerization initiator system according to claim 1 or 2, wherein the component (C) is an aliphatic amine. A method for producing a polymer, comprising subjecting at least one radical polymerizable monomer to living radical polymerization in the presence of the living radical polymerization initiator system according to claim 1. The production method according to claim 4, wherein the radical polymerizable monomer is at least one radical polymerizable monomer selected from the group consisting of a styrene monomer, a methacrylic ester and an acrylic ester. The production method according to claim 4, wherein at least two kinds of radical polymerizable monomers are used for copolymerization. The manufacturing method of Claim 6 using the at least 2 sort (s) of radically polymerizable monomer chosen from the group which consists of a styrene-type monomer, methacrylic acid ester, and acrylic acid ester.