JP5495736B2 - Improved polymerization process - Google Patents

Description

  The present invention relates to a polymerization method characterized by improving the activity of polymerization terminals during polymerization in controlled radical polymerization.

  In recent years, a controlled radical polymerization method has been developed and has been actively researched by various groups. In the controlled radical polymerization method, the molecular weight can be freely controlled by the charging ratio of the radical polymerizable monomer and the polymerization initiator. Among the controlled radical polymerization methods, a method of polymerizing a radical polymerizable monomer using an organic halide or the like as a polymerization initiator and a transition metal complex as a polymerization catalyst, in addition to the characteristics of the above controlled radical polymerization method, Since the compound has a halogen or the like that is relatively advantageous for functional group conversion reaction at the terminal and has a high degree of freedom in designing a polymerization initiator and a polymerization catalyst, it is preferable as a method for producing a polymer having a specific functional group.

Examples of the polymerization using the transition metal complex as a polymerization catalyst include the methods described in Patent Documents 1 and 2.
Controlled radical polymerization using a transition metal complex as a polymerization catalyst can be carried out in various solvents including hydrocarbon solvents such as toluene and nitrile solvents such as acetonitrile. Among these solvents, it is known that the polymerization rate is improved when dimethyl sulfoxide is used (Non-patent Document 1).

  However, in general, in controlled radical polymerization using a transition metal complex as a polymerization catalyst, a termination reaction occurs as the polymerization proceeds, and the polymerization conversion tends to be difficult to increase. In recent years, it has been pointed out that in the presence of dimethylformamide and dimethyl sulfoxide, a transition metal complex as a polymerization catalyst is deactivated by a disproportionation reaction over time (Non-patent Document 1).

International Publication No. 96/30421 Pamphlet International Publication No. 97/47661 Pamphlet

Macromolecules, 2007, 40, 7795-7806.

The object of the present invention is to prevent a decrease in the polymerization rate until the end of the polymerization in the controlled radical polymerization in the presence of dimethylformamide, dimethylacetamide, dimethylsulfoxide or a mixture thereof .

As a result of intensive studies on the above problems, the present inventors have found that the activity of the polymerization terminal is improved by adding cuprous bromide during the polymerization in the controlled radical polymerization, leading to the present invention. .

That is, the present invention is a controlled radical polymerization method for obtaining a polymer using the following (a) to (e), wherein the following (a) to (e) are mixed at the start of polymerization, This is a controlled radical polymerization method in which (c) is further added when the polymerization conversion is 5 to 95%:
(A) a radically polymerizable monomer;
(B) dimethylformamide, dimethylacetamide, dimethylsulfoxide or mixtures thereof ;
(C) cuprous bromide ;
(D) a polyamine compound capable of forming a complex with (c);
(E) An organic halide which is a polymerization initiator.
Moreover, this invention is a polymer obtained by superposing | polymerizing said (a) by said control radical polymerization method.
Moreover, this invention is a manufacturing method of the polymer which superposes | polymerizes said (a) by said control radical polymerization method.

According to the present invention, in the controlled radical polymerization in the presence of dimethylformamide, dimethylacetamide, dimethyl sulfoxide or a mixture thereof, it is possible to prevent a decrease in polymerization rate until the end of polymerization and shorten the polymerization time. . Moreover, since it is possible to predict the polymerization end time from the amount and timing of cuprous bromide to be added, it is possible to save the trouble of checking the polymerization conversion rate and the residual monomer amount.

The relationship between the polymerization time in the presence of dimethylformamide and the amount of monomer consumption [= ln ((monomer concentration at the start of polymerization) / (monomer concentration))] is shown. The arrow (solid line) in the figure indicates the addition of cuprous bromide in Example 1, and the arrow (broken line) indicates the addition of cuprous bromide in Example 2. The relationship between the polymerization time in the presence of dimethylformamide and the amount of monomer consumption [= ln ((monomer concentration at the start of polymerization) / (monomer concentration))] is shown. The arrow (solid line) in the figure indicates the addition of cuprous bromide in Example 3. The relationship between the polymerization time in the presence of dimethylformamide and the amount of monomer consumption [= ln ((monomer concentration at the start of polymerization) / (monomer concentration))] is shown. The arrow (solid line) in the figure indicates the addition of cuprous bromide in Example 4. The relationship between the polymerization time in the presence of dimethylacetamide and the monomer consumption [= ln ((monomer concentration at the start of polymerization) / (monomer concentration))] is shown. The arrow (solid line) in the figure indicates the addition of cuprous bromide in Example 5. The relationship between the polymerization time in the presence of dimethyl sulfoxide and the consumption of monomer [= ln ((monomer concentration at the start of polymerization) / (monomer concentration))] is shown. The arrow (solid line) in the figure indicates the addition of cuprous bromide in Example 6. The relationship between the polymerization time in the presence of acetonitrile and the monomer consumption [= ln ((monomer concentration at the start of polymerization) / (monomer concentration))] is shown. The arrow (solid line) in the figure indicates the addition of cuprous bromide in Comparative Example 5. The relationship between the polymerization time in the presence of dimethylformamide and the amount of monomer consumption [= ln ((monomer concentration at the start of polymerization) / (monomer concentration))] is shown. In the figure, the arrow (thin solid line) is in Example 7, the arrow (thin broken line) is in Example 8, the arrow (thick solid line) is in Example 9, and the arrow (thick broken line) is in Example 10. The addition of cuprous bromide at.

Hereinafter, the present invention will be described in detail.
Examples of the radical polymerizable monomer (a) used in the present invention include (meth) acrylic acid; (meth) methyl acrylate, (meth) acrylate ethyl, (meth) acrylate-n-propyl, (meth) ) Isopropyl acrylate, (meth) acrylic acid-n-butyl, (meth) acrylic acid isobutyl, (meth) acrylic acid-sec-butyl, (meth) acrylic acid-t-butyl, (meth) acrylic acid-n- Pentyl, (meth) acrylic acid-n-hexyl, (meth) acrylic acid cyclohexyl, (meth) acrylic acid-n-heptyl, (meth) acrylic acid-n-octyl, (meth) acrylic acid-2-ethylhexyl, ( (Meth) acrylic acid nonyl, (meth) acrylic acid decyl, (meth) acrylic acid dodecyl, (meth) acrylic acid stearyl, (meth) acrylic acid Bornyl, phenyl (meth) acrylate, toluyl (meth) acrylate, benzyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, (meth) acrylic acid -3-methoxybutyl, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, 2-aminoethyl (meth) acrylate, γ- (methacryloyloxy) (Propyl) trimethoxysilane, (meth) acrylic acid ethylene oxide adduct, (meth) acrylic acid (trifluoromethyl) methyl, (meth) acrylic acid (2-trifluoromethyl) ethyl, (meth) acrylic acid (2 -Perfluoroethyl) ethyl, (meth) acrylic acid (2-perfluoroethyl) ( 2-perfluorobutyl) ethyl, perfluoroethyl (meth) acrylate, perfluoromethyl (meth) acrylate, (meth) acrylic acid (diperfluoromethyl) methyl, (meth) acrylic acid (perfluoromethyl) ( Perfluoroethyl) methyl, (meth) acrylic acid (2-perfluorohexyl) ethyl, (meth) acrylic acid (2-perfluorodecyl) ethyl, (meth) acrylic acid (2-perfluorohexadecyl) ethyl, etc. (Meth) acrylic acid esters; aromatic vinyl monomers such as styrene, vinyl toluene, α-methyl styrene, chlorostyrene, styrene sulfonic acid and salts thereof; silicon-containing single quantities such as vinyl trimethoxy silane and vinyl triethoxy silane Body; maleic anhydride, maleic acid, maleic acid monoalkyl ester Fumaric acid, monoalkyl and dialkyl esters of fumaric acid; maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-butylmaleimide, N-hexylmaleimide, N-octylmaleimide, N -Maleimide monomers such as dodecylmaleimide, N-stearylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide; vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; amide group-containing monomers such as acrylamide and methacrylamide Mer: vinyl esters such as vinyl acetate, vinyl propionate, vinyl pivalate, vinyl benzoate, vinyl cinnamate; ethylene, propylene, vinylidene fluoride, perfluoroethylene, perfluoropropylene Olefins such as vinyl chloride and vinylidene chloride; conjugated dienes such as butadiene and isoprene; and allylic monomers such as allyl chloride and allyl alcohol. These can be used alone or in combination of two or more.
Of these, (meth) acrylic acid esters, aromatic vinyl monomers, and vinyl cyanide monomers are preferred, and (meth) acrylic acid esters are more preferred, from the physical properties of the resulting polymer.
In the present invention, “(meth) acryl” represents “methacryl” or “acryl”.
In this invention, it is preferable that the content rate at the time of the polymerization start of a radically polymerizable monomer (a) is 3-90 mass% with respect to the whole polymerization system (100 mass%), and is 15-75 mass%. More preferably. In addition, the whole polymerization system here refers to the above-mentioned (a) to (e) to which a solvent described later is added.
If the content rate of (a) with respect to the whole polymerization system is 3% by mass or more, the polymerization rate at the initial stage of polymerization is improved, and if it is 90% by mass or less, an increase in the viscosity of the polymerization system at the end of polymerization is suppressed.
The “monomer concentration” in FIGS. 1 to 7 is obtained by converting the content of (a) to the molar concentration with respect to the entire polymerization system.

Examples of the carboxylic acid amide, sulfoxide or a mixture thereof (b) used in the present invention include dimethylformamide, dimethylacetamide, dimethyl sulfoxide or a mixture thereof.
In the present invention, the content of the carboxylic acid amide, sulfoxide or a mixture thereof (b) at the start of polymerization is preferably 5 to 95% by mass with respect to the entire polymerization system (100% by mass), and 20 to 80%. More preferably, it is mass%.
If the content of (b) with respect to the entire polymerization system is 5% by mass or more, the solubility of the transition metal complex does not decrease, so the polymerization rate does not decrease. The content of the metal complex is appropriate, and the polymerization rate does not decrease.

As the transition metal compound (c) used in the present invention, for example,
MX _n
(M is a transition metal selected from the group consisting of Cu, Fe, Ru, Cr, Mo, W, Rh, Re, Co, V, Zn, Au, and Ag, X is a halogen atom, and n is a transition metal. Formal charge (0 ≦ n ≦ 7)
Is mentioned. When n is 0, it is a “transition metal”. That is, the “transition metal compound (c)” in the present invention is a concept including “transition metal” as well as “transition metal compound” composed of a transition metal atom and a halogen atom. These can be used alone or in combination of two or more.
Among these, from the viewpoint of controllability as a controlled radical polymerization catalyst, M is preferably Cu, X is preferably chlorine, bromine or iodine, n is preferably 0 to 2, copper, chloride. Cuprous and cuprous bromide are more preferable.
The transition metal compound (c) may be added as it is, or may be added as a solution or dispersion of a suitable solvent.
In this invention, it is preferable that the content rate at the time of the polymerization start of a transition metal compound (c) is 0.05-5 mass% with respect to the whole polymerization system (100 mass%). When the content of (c) with respect to the entire polymerization system is 0.05% by mass or more, the polymerization rate at the initial stage of polymerization is improved, and when it is 5% by mass or less, the molecular weight distribution at the initial stage of polymerization can be narrowed.

In the present invention, the transition metal compound (c) is further added when the polymerization conversion rate of the radical polymerizable monomer (a) is 5 to 95%. By doing so, the activity of the polymerization terminal is improved, and even in the case of controlled radical polymerization in the presence of carboxylic acid amide or sulfoxide, it is possible to prevent a decrease in polymerization rate until the end of the polymerization. The transition metal compound (c) may be added once, or may be added in two or more times, but the effect of improving the polymerization rate is greater when added in two or more times.
The amount of the transition metal compound (c) added when the polymerization conversion rate of the radically polymerizable monomer (a) is 5 to 95% is 0.05 to 5 mass with respect to the entire polymerization system (100 mass%). % Is preferred. If the amount of the transition metal compound (c) added when the polymerization conversion rate of (a) is 5 to 95% is 0.05% by mass or more, the effect of improving the polymerization rate by the addition of the transition metal compound (c) can be obtained. If it is easy to express and is 5% by mass or less, the resulting polymer can be easily purified.
The timing of further adding the transition metal compound (c) is when the polymerization conversion rate of (a) is 5 to 95%, and preferably 20 to 95%. If the polymerization conversion rate of (a) is 5% or more, the effect of improving the polymerization rate due to the addition of the transition metal compound (c) is easily exhibited, and if the polymerization conversion rate is 95% or less, the molecular weight distribution of the polymer obtained Can be kept narrow.
In the controlled radical polymerization, unlike ordinary radical polymerization using an azo polymerization initiator or the like, a balance between the polymerization rate of the monomer and the control ability is important. In other words, when a polymerization catalyst is added later in controlled radical polymerization using a transition metal complex as a polymerization catalyst, the radical generation amount may increase (halogen extraction reaction) depending on the conditions, and the polymerization rate may be improved. Occurrence is suppressed (halogen supply reaction from the transition metal complex), and apparently the polymerization rate does not change in many cases. In addition, when a polymerization catalyst is added afterwards, in many cases, the polymerization control becomes difficult and the molecular weight distribution of the polymer tends to be widened.
Therefore, in the present invention, the transition metal compound (c), which is one of the polymerization catalyst, is post-added instead of the polymerization catalyst itself. That is, in the controlled radical polymerization in the presence of (b), in order to supplement the polymerization catalyst (transition metal complex) that is deactivated over time, a transition metal compound (c) is added afterwards to prevent a decrease in polymerization rate. It is out. By doing so, it is possible to narrow the molecular weight distribution of the polymer while improving the polymerization rate of the monomer.

The polyamine compound (d) that can form a complex with the transition metal compound (c) used in the present invention is preferably an amine-based ligand.
Examples of amine-based ligands include bipyridyl compounds such as 2,2′-bipyridyl or derivatives thereof; 1,10-phenanthroline or derivatives thereof; hexamethyltriethylenetetraamine, bispicolylamine, trialkylamine, and tetramethyl. Examples include ethylenediamine, pentamethyldiethylenetriamine, and hexamethyl (2-aminoethyl) amine. These can be used alone or in combination of two or more.
Among these, pentamethyldiethylenetriamine and hexamethyl (2-aminoethyl) amine are preferable.
Moreover, when using a copper compound as a transition metal compound (c), it is preferable that an amine-type ligand is a compound which has three or more amino groups.

  In addition, although the amino group in this invention represents group which has a nitrogen atom-carbon atom bond, it is preferable that a nitrogen atom couple | bonds only with a carbon atom and / or a hydrogen atom among these.

  The molar ratio ((c) / (d)) between the transition metal compound (c) and the polyamine compound (d) at the start of polymerization is preferably 0.1 to 2, and preferably 0.5 to 1. More preferred. If the molar ratio of (c) / (d) is 0.1 or more, the polymerization rate at the initial stage of polymerization is improved, and if it is 2 or less, the transition metal compound not involved in the polymerization does not become excessive (c). The resulting polymer is easy to purify.

  As the organic halide (e) used as a polymerization initiator in the present invention, a monofunctional, difunctional, or polyfunctional compound can be used. Although these can be used properly according to the objective, when manufacturing an AB diblock copolymer, since the acquisition of a polymerization initiator is easy, a monofunctional compound is preferable. When producing an A-B-A type triblock copolymer or a B-A-B type triblock copolymer, use a bifunctional compound in terms of the number of polymerization steps and shortening the polymerization time. Is preferred. When manufacturing a branched block copolymer, it is preferable to use a polyfunctional compound from the viewpoint of shortening the number of polymerization steps and polymerization time.

Examples of monofunctional compounds include:
R ¹ —C (H) (X) —COOR ² ,
R ¹ —C (CH ₃ ) (X) —COOR ² ,
R ¹ —C (H) (X) —CO—R ² ,
R ¹ —C (CH ₃ ) (X) —CO—R ² ,
R ¹ —C (H) (X) —CN,
R ¹ —C (CH ₃ ) (X) —CN,
The compound shown by these is mentioned. In the formula, R ¹ represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. X represents chlorine, bromine or iodine. R ² represents a monovalent organic group having 1 to 20 carbon atoms.
Specific examples of the alkyl group having 1 to 20 carbon atoms (including the alicyclic hydrocarbon group) as R ¹ include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, t- A butyl group, n-pentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, dodecyl group, and isobornyl group can be mentioned.
Specific examples of the aryl group having 6 to 20 carbon atoms include a phenyl group, a triyl group, and a naphthyl group.
Specific examples of the aralkyl group having 7 to 20 carbon atoms include benzyl group and phenethyl group.
Specific examples of the monofunctional compound include methyl 2-bromide propionate, ethyl 2-bromide propionate, butyl 2-bromide propionate, methyl 2-bromide isobutyrate, ethyl 2-bromide isobutyrate, Examples include 2-butyl isobutyrate, 2-bromopropiononitrile, and 2-isobutyronitrile bromide. Among these, ethyl 2-bromide propionate, butyl 2-bromide propionate, 2-bromide propiononitrile and 2-bromoisobutyronitrile are preferable from the point of fast elimination of halogen groups. .

As a bifunctional compound, for example,
^{XCH (COOR 3) - (CH} 2) n -CH (COOR 3) -X,
^{_{XC (CH 3) (COOR 3}} ) - (CH 2) n -C (CH 3) (COOR 3) -X,
_{XCH 2 -COO- (CH 2) n} -OCO-CH 2 -X,
_{XCH (CH 3) -COO- (CH} 2) n -OCO-CH (CH 3) -X,
_{XC (CH 3) 2 -COO- (} CH 2) n -OCO-C (CH 3) 2 -X,
_{XCH 2 -COO-C 6 H 4} -OCO-CH 2 -X,
_{XCH (CH 3) -COO-C} 6 H 4 -OCO-CH (CH 3) -X,
_{XC (CH 3) 2 -COO-} C 6 H 4 -OCO-C (CH 3) 2 -X,
The compound shown by these is mentioned. In the formula, R ³ represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. n represents an integer of 0 to 20. C ₆ H ₄ represents a divalent phenyl group. X represents chlorine, bromine or iodine.
Specific examples of the alkyl group having 1 to 20 carbon atoms, the aryl group having 6 to 20 carbon atoms, and the aralkyl group having 7 to 20 carbon atoms of R ³ are the same as the specific examples of R ¹ described above.
Specific examples of the bifunctional compound include dimethyl 2,3-dibromosuccinate, diethyl 2,3-dibromosuccinate, dimethyl 2,4-dibromoglutarate, diethyl 2,4-dibromoglutarate, 2,4- Dibutyl dibromoglutarate, dimethyl 2,5-dibromoadipate, diethyl 2,5-dibromoadipate, dimethyl 2,6-dibromopimelate (dimethyl-2,6-dibromoheptanedioate), diethyl 2,6-dibromopimelate Dimethyl 2,7-dibromosuberate, diethyl 2,7-dibromosuberate. Among these, diethyl 2,5-dibromoadipate, dimethyl 2,6-dibromopimelate, and diethyl 2,6-dibromopimelate are preferable because of easy availability of raw materials.

As the multifunctional compound, for example,
_{C 6 H 3 - (CH 2} -X) 3,
_{C 6 H 3 - (CH (} CH 3) -X) 3,
_{C 6 H 3 - (C (} CH 3) 2 -X) 3,
The compound shown by these is mentioned. In the formula, C ₆ H ₃ represents a trivalent phenyl group (the positions of the three bonds may be any combination of the 1st to 6th positions), and X represents chlorine, bromine or iodine.
Specific examples of the polyfunctional compound include tris (1-bromoethyl) benzene, tris (1-bromoisopropyl) benzene, and tris (bromomethyl) benzene. Among these, tris (bromomethyl) benzene is preferable because it is easy to obtain raw materials.

When an organic halide having a functional group other than the group that initiates polymerization is used, a polymer in which a functional group other than the group that initiates polymerization is easily introduced into the terminal or in the molecule can be obtained. Examples of functional groups other than the group that initiates polymerization include alkenyl groups, hydroxyl groups, epoxy groups, amino groups, amide groups, silyl groups, and the like.
In the organic halide that can be used as the polymerization initiator, carbon to which a halogen group (halogen atom) is bonded is bonded to a carbonyl group or a phenyl group, and the carbon-halogen bond is activated to perform polymerization. Start.
In this invention, it is preferable that the content rate at the time of the polymerization start of the organic halide (e) which is a polymerization initiator is 0.05-5 mass% with respect to the whole polymerization system (100 mass%).
If the content rate of (e) with respect to the whole polymerization system is 0.05 mass% or more, the polymerization rate at the initial stage of polymerization is improved, and if it is 5 mass% or less, side reactions such as termination reactions can be suppressed.
In addition, what is necessary is just to determine the quantity of (e) to be used from ratio with a monomer according to the molecular weight of the polymer made into a manufacture objective. That is, the molecular weight of the polymer can be controlled by the number of radically polymerizable monomers used per molecule of the organic halide (e) that is a polymerization initiator.

The atmosphere for polymerization is preferably an oxygen-free atmosphere. Oxygen easily reacts with radicals to inhibit polymerization, and in the presence of oxygen, the polymerization catalyst may be oxidized and lose activity.
The polymerization temperature can be carried out in the range of 0 to 200 ° C, preferably in the range of room temperature to 150 ° C.
The polymerization mixture is preferably stirred well. In particular, when the transition metal compound is added, sufficient stirring is preferable in order to quickly and uniformly diffuse the transition metal compound.
The polymerization method can be applied to batch polymerization, semi-batch polymerization in which monomers are added, continuous polymerization, and the like.

In the present invention, a solvent can be used as necessary. Examples of the solvent include hydrocarbon solvents such as benzene and toluene; ether solvents such as diethyl ether and tetrahydrofuran; halogenated hydrocarbon solvents such as methylene chloride and chloroform; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone. Solvent: Alcohol solvents such as methanol, ethanol, propanol, isopropanol, n-butyl alcohol and t-butyl alcohol; Nitrile solvents such as acetonitrile, propionitrile and benzonitrile; Esters such as ethyl acetate and n-butyl acetate Solvent; carbonate solvents such as ethylene carbonate and propylene carbonate are listed. These can be used alone or in combination of two or more.
Polymerization can also be carried out in an emulsion system or a system using supercritical fluid CO ₂ as a medium.
The polymer obtained by the controlled radical polymerization method of the present invention can be used for various applications. Applications of the obtained polymer include, for example, a coating composition utilizing a narrow molecular weight distribution, a thermoplastic composition utilizing a block polymer, a curable composition by heat or light, and an adhesive. Compositions, adhesive compositions, and molding materials such as films and sheets.

EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to these Examples.
The polymerization conversion rate of the monomer, the composition of the polymer, the number average molecular weight and the molecular weight distribution were measured by the following methods.
(1) Polymerization conversion rate ¹ H-NMR (manufactured by JEOL Ltd., “JNM-EX270” (trade name)) was used for measurement.
The reaction solution collected during or after polymerization is dissolved in deuterated chloroform, and the peak derived from the double bond of the monomer and the peak derived from the hydrogen of the hydrocarbon group bonded to the ester group of the polymer are integrated. From the intensity ratio, the polymerization conversion rate of the monomer was measured. The measurement temperature is 25 ° C., and the number of integration is 16 times.

(2) Number average molecular weight (Mn) and molecular weight distribution (PDI)
GPC (manufactured by Tosoh Corporation, “HLC-8220” (trade name), column: TSK GUARD COLUMN SUPER HZ-L (4.6 × 35 mm), TSK-GEL SUPER HZM-N (6.0 × 150 mm) × 2 series connection, eluent: chloroform, measurement temperature: 40 ° C., flow rate: 0.6 mL / min), and measurement was performed using polymethyl methacrylate as a standard.

<Example 1>
200 mL Schlenk was charged with butyl acrylate (24 g, 0.187 mol), cuprous bromide (269 mg, 1.87 mmol), and dimethylformamide (24 g), and purged with nitrogen by bubbling. Stir well, add pentamethyldiethylenetriamine (hereinafter referred to as “PMDETA”) (0.4 mL, 1.87 mmol), raise the temperature until the internal temperature reaches 70 ° C., stir at the same temperature for 10 minutes, The complex of cuprous bromide and PMDETA was dissolved.
Ten minutes later, dimethyl-2,6-dibromoheptanedioate (0.2 mL, 0.937 mmol) was added as a polymerization initiator to initiate polymerization. After 1 hour had elapsed from the start of polymerization (polymerization conversion rate 85%), cuprous bromide (269 mg, 1.87 mmol) was added, and polymerization was further performed for 2 hours. On the way, the polymerization solution was sampled using a syringe at regular intervals.
The polymerization conversion after 3 hours from the start of polymerization was 97%, Mn by GPC was 32100, and PDI was 1.35.

<Example 2>
The polymerization operation was performed in the same manner as in Example 1 except that the amount of cuprous bromide at the time of preparation was changed to 538 mg (3.75 mmol). The polymerization conversion rate when cuprous bromide was added was 92%.
The polymerization conversion rate 3 hours after the start of polymerization was 98%, Mn by GPC was 29200, and PDI was 1.48.

<Example 3>
The amount of cuprous bromide at the time of charging was 53 mg (0.369 mmol), and brominated after 30 minutes from the start of polymerization (polymerization conversion rate 34%) and after 1 hour (polymerization conversion rate 76%), respectively. The polymerization operation was performed in the same manner as in Example 1 except that 108 mg (0.753 mmol) of cuprous was added.
The polymerization conversion rate after 3 hours from the start of polymerization was 92%, Mn by GPC was 23700, and PDI was 1.19.

<Example 4>
The amount of cuprous bromide at the time of charging was 135 mg (0.937 mmol), 30 minutes after the start of polymerization (polymerization conversion rate 49%), 1 hour later (polymerization conversion rate 81%), and 1 hour 30 The polymerization operation was performed in the same manner as in Example 1 except that 135 mg (0.937 mmol) of cuprous bromide was added after the lapse of minutes (polymerization conversion rate 90%).
The polymerization conversion rate 3 hours after the start of polymerization was 98%, Mn by GPC was 29000, and PDI was 1.27.

<Example 5>
The polymerization operation was carried out in the same manner as in Example 1 except that 24 g of dimethylacetamide was used instead of 24 g of dimethylformamide. The polymerization conversion rate when cuprous bromide was added was 50%.
After 6 hours from the start of polymerization, the polymerization conversion was 89%, MPC by GPC was 23900, and PDI was 1.19.

<Example 6>
The amount of cuprous bromide at the time of charging was 67.5 mg (0.469 mmol), the amount of PMDETA was 0.1 mL (0.469 mmol), and the amount of dimethyl-2,6-dibromoheptanedioate was 0.1 mL ( 0.469 mmol), methyl acrylate (32 g, 0.371 mol) was used instead of 24 g of butyl acrylate, and 32 g of dimethyl sulfoxide was used instead of 24 g of dimethylformamide, after 1 hour from the start of polymerization (polymerization conversion rate 66% The polymerization operation was carried out in the same manner as in Example 1 except that the amount of cuprous bromide added to 67.5 mg (0.469 mmol) was added.
The polymerization conversion rate after 4 hours from the initiation of polymerization was 92%, Mn by GPC was 67900, and PDI was 1.31.

<Example 7>
A 300 mL three-necked round bottom flask was used as a reaction vessel, the amount of butyl acrylate at the time of charging was 48 g (0.374 mol), the amount of cuprous bromide was 135 mg (0.937 mmol), the amount of dimethylformamide was 48 g, PMDETA Was 0.2 mL (0.938 mmol) and dimethyl-2,6-dibromoheptanedioate was 0.1 mL (0.469 mmol), and 30 minutes after the start of polymerization (polymerization conversion rate 38%) The polymerization operation was carried out in the same manner as in Example 1 except that 135 mg (0.937 mmol) of cuprous bromide was added.
After 6 hours from the start of polymerization, the polymerization conversion was 89%, the MPC Mn was 92700, and the PDI was 1.22.

<Example 8>
The polymerization operation was performed in the same manner as in Example 7 except that cuprous bromide was added after 1 hour from the start of polymerization (polymerization conversion: 47%).
After 6 hours from the start of polymerization, the polymerization conversion was 89%, MPC MPC was 87800, and PDI was 1.23.

<Example 9>
The polymerization operation was performed in the same manner as in Example 7 except that cuprous bromide was added after the lapse of 2 hours from the start of polymerization (polymerization conversion rate: 67%).
The polymerization conversion ratio 6 hours after the start of polymerization was 91%, Mn by GPC was 93600, and PDI was 1.26.

<Example 10>
The polymerization operation was carried out in the same manner as in Example 7 except that cuprous bromide was added after 4 hours from the start of polymerization (polymerization conversion rate 75%).
The polymerization conversion ratio after 6 hours from the start of polymerization was 88%, Mn by GPC was 87100, and PDI was 1.27.

<Comparative Example 1>
The polymerization operation was performed in the same manner as in Example 1 except that cuprous bromide was not added after the start of polymerization.
The polymerization conversion rate after 3 hours from the start of polymerization was 89%, Mn by GPC was 24900, and PDI was 1.25.

<Comparative example 2>
The polymerization operation was performed in the same manner as in Example 2 except that cuprous bromide was not added after the start of polymerization.
The polymerization conversion rate after 3 hours from the initiation of polymerization was 96%, Mn by GPC was 37400, and PDI was 1.38.

<Comparative Example 3>
The polymerization operation was performed in the same manner as in Example 5 except that cuprous bromide was not added after the start of polymerization.
The polymerization conversion ratio after 6 hours from the start of polymerization was 80%, Mn by GPC was 20900, and PDI was 1.15.

<Comparative Example 4>
The polymerization operation was performed in the same manner as in Example 6 except that cuprous bromide was not added after the start of polymerization.
The polymerization conversion rate after 4 hours from the start of polymerization was 76%, Mn by GPC was 57200, and PDI was 1.25.

<Comparative Example 5>
Similar to Example 1 except that 24 g of acetonitrile was used instead of 24 g of dimethylformamide, and cuprous bromide (269 mg, 1.87 mmol) was added after 4 hours from the start of polymerization (polymerization conversion 71%). The polymerization operation was carried out.
After 6 hours from the start of polymerization, the polymerization conversion was 80%, and MDI 20800 by GPC had a PDI of 1.08.

<Comparative Example 6>
The polymerization operation was performed in the same manner as in Comparative Example 5 except that cuprous bromide was not added after the start of polymerization.
The polymerization conversion ratio 6 hours after the start of polymerization was 77%, Mn by GPC was 20300, and PDI was 1.08.

<Comparative Example 7>
The polymerization operation was performed in the same manner as in Example 7 except that cuprous bromide was not added after the start of polymerization.
The polymerization conversion ratio 6 hours after the start of the polymerization was 79%, Mn by GPC was 73700, and PDI was 1.15.

<Comparative Example 8>
The polymerization operation was performed in the same manner as in Example 7 except that the amount of cuprous bromide at the time of preparation was 269 mg (1.87 mmol), and cuprous bromide was not added after the start of polymerization.
The polymerization conversion ratio 6 hours after the start of polymerization was 87%, Mn by GPC was 88300, and PDI was 1.26.

<Evaluation>
The results of Examples 1 and 2 and Comparative Examples 1 and 2 are shown in FIG. 1, the results of Example 3 and Comparative Example 1 are shown in FIG. 2, the results of Examples 4 and 2 are shown in FIG. The results of Comparative Example 3 are shown in FIG. 4, the results of Example 6 and Comparative Example 4 are shown in FIG. 5, the results of Comparative Examples 5 and 6 are shown in FIG. 6, and the results of Examples 7-10 and Comparative Examples 7 and 8 are shown. As shown in FIG.

  As shown in FIG. 1, in the case of controlled radical polymerization in the presence of dimethylformamide, when cuprous bromide was added when the polymerization conversion rate of (a) was 5 to 95% (Examples 1 and 2), It was found that the polymerization rate was improved as compared with the case where the addition was not made (Comparative Examples 1 and 2), and the activity of the polymerization terminal during the polymerization was improved. Further, when the same amount of cuprous bromide was charged at the start of polymerization (Comparative Example 2), it was added in portions at the start of polymerization and when the polymerization conversion rate of (a) was 5 to 95%. In the case (Example 1), the latter improved the polymerization rate.

  As shown in FIGS. 2 and 3, compared with the case where cuprous bromide was charged at the beginning of polymerization, the polymerization was added at the start of polymerization and at a time when the polymerization conversion of (a) was 5 to 95%. Thus, the effect of improving the polymerization rate was also observed when cuprous bromide at the start of polymerization was reduced ((c) / (d) molar ratio was 1 or less).

  As shown in FIGS. 4 and 5, in the controlled radical polymerization in the presence of dimethyl sulfoxide and dimethyl sulfoxide, as in the presence of dimethylformamide, the first bromide bromide at the time when the polymerization conversion of (a) is 5 to 95%. A difference in polymerization rate was observed depending on whether or not copper was added.

  As shown in FIG. 7, in the case of controlled radical polymerization in the presence of dimethylformamide, when cuprous bromide was added at different points in time when the polymerization conversion rate of (a) was in the range of 5 to 95% (Examples 7 to In 10), the polymerization rate was improved as compared with the case where it was not added (Comparative Example 7) and the case where the same amount of cuprous bromide was charged at the start of polymerization (Comparative Example 8).

  Thus, in the controlled radical polymerization performed in the presence of carboxylic acid amide or sulfoxide, the activity of the polymerization terminal during the polymerization can be increased by adding the transition metal compound when the polymerization conversion of (a) is 5 to 95%. It has been found that the polymerization rate can be prevented from decreasing until the end of the polymerization.

  In addition, in the controlled radical polymerization in the presence of acetonitrile as shown in FIG. 6, when adding cuprous bromide when the polymerization conversion rate of (a) is 5 to 95% (Comparative Example 5) and not adding In the case (Comparative Example 6), no significant difference was observed in the polymerization rate, and no improvement in the activity of the polymerization terminal during the polymerization due to the addition of the transition metal compound was observed. The reason for this is considered that the polymerization catalyst is not deactivated in the case of Comparative Example 5, and the amount of the active polymerization catalyst does not change even if a transition metal compound (cuprous bromide) is added later. .

Claims (4)

A controlled radical polymerization method for obtaining a polymer using the following (a) to (e):
The controlled radical polymerization method in which the following (a) to (e) are mixed and used at the start of polymerization, and (c) is further added when the polymerization conversion rate of (a) is 5 to 95%:
(A) a radically polymerizable monomer;
(B) dimethylformamide, dimethylacetamide, dimethylsulfoxide or mixtures thereof ;
(C) cuprous bromide ;
(D) a polyamine compound capable of forming a complex with (c);
(E) An organic halide which is a polymerization initiator.   The controlled radical polymerization method according to claim 1, wherein a molar ratio ((c) / (d)) of (c) and (d) at the start of polymerization is 0.1 to 2.   The polymer obtained by superposing | polymerizing said (a) by the controlled radical polymerization method of Claim 1 or 2.   The manufacturing method of the polymer which superposes | polymerizes said (a) by the controlled radical polymerization method of Claim 1 or 2.

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