JPH05202112A - Halomethyl group-containing azo-based polymerization initiator, macromolecular polymerization initiator synthesized from the same initiator and production of block polymer using the same initiator - Google Patents

Abstract

PURPOSE:To provide the subject halomethyl group-containing azo-based polymerization initiator capable of readily synthesizing a macromolecular polymerization initiator having one or the other of the initiating groups by using an ethylenic unsaturated monomer and of reaidily synthesizing a block copolymer. CONSTITUTION:(A) A halomethyl group-containing azo-based polymerization initiator of formula I [R<1> is formulae II to IV (n and m are natural number of 1 to 10); R'' is a 1 to 5C alkyl; Y is a halomethyl group having one or more halogens] obtained by (A1): reacting a halomethyl group-containing carboxyl acid halide with an azo-based polymerization initiator having OH groups at both the terminals or by (A2): reacting a halomethyl group-containing alcohol with an azo-based polymerization initiator having carboxylic acid halides at both the terminals. (B) (B1): An azo group-containing macromolecular polymerization initiator obtained by reacting a reducing agent on A and carrying out redox radical polymerization of an ethylenic unsaturated monomer. (B2): A halomethyl group-containing macromolecular polymerization initiator obtained by thermal radical polymerization of A with an ethylenic monomer. (C) A block polymer obtained by polymerizing an ethylenic monomer in the presence of A or B.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an azo polymerization initiator having a halomethyl group. More specifically, the present invention can synthesize an azo group-containing polymer by redox radical polymerizing an ethylenically unsaturated monomer by acting a reducing agent on the halomethyl group in the molecule, while using the azo group in the molecule. The present invention relates to an azo-based polymerization initiator capable of synthesizing a halomethyl group-containing polymer by radically heat-polymerizing an ethylenically unsaturated monomer, and a method for producing the same. Both of these azo group-containing polymers and halomethyl group-containing polymers are polymer polymerization initiators capable of initiating polymerization by the action of heat or a reducing agent. Further, a method of producing a block copolymer by carrying out polymerization using these polymerization initiators is also included.

[0002]

2. Description of the Related Art Polymerization initiators having initiating groups having different initiation temperatures or initiation mechanisms in the molecule are useful for synthesizing block polymers. That is, using a polymerization initiator having a low-temperature initiation group A and a high-temperature initiation group B in the same molecule, A is initiated and B is polymerized with the first monomer under the condition of being stored, and the initiation group B is intramolecularly added. To synthesize the polymer polymerization initiator contained in. Using this polymer polymerization initiator, the initiation group B
Then, the second monomer is polymerized under the condition that starts to obtain a block copolymer. An initiator having an azo group and a peroxide group has been proposed as an initiator having such a different initiator group (JSN Su, I. Pirma,
Journalof Applied Polymer
Science 33, (1987) p. 727 et seq.), And few specific examples thereof have been reported. The reason is that such an initiator is inherently difficult to synthesize, as described below.

[0003]

The initiator having the different kinds of initiation groups needs to satisfy the following conditions.

There is a sufficient difference between the starting temperatures of the two starting groups. Usually, a difference of 30 ° C. or more is desired. It is desirable that the low-temperature starting group A is sufficiently stable even at room temperature, and the higher the starting temperature, the better for storage stability. It is desirable that the starting temperature of the high-temperature initiating group B is not so high in order to prevent side reactions during polymerization. Usually 8
0 ° C. or lower is desired. Of these conditions, it is inconsistent to try to satisfy, and to satisfy one, one must sacrifice or, and these three parties are in a trade-off relationship with each other. It is extremely difficult to satisfy both and.

In order to satisfy these three conditions to some extent, for example, even if the molecular design of the initiator is planned by selecting a low temperature starting temperature of 50 ° C. and a high temperature starting temperature of 80 ° C., a compound satisfying those conditions is found, In reality, it is extremely difficult to design the molecule because the combination of the starting groups is limited to the azo group or the peroxide group. Therefore, ditertiary butyl-4 in the above-mentioned literature,
4'-azobis- (4-cyanoperoxyvalerate)
There are almost no other reports. Since this compound has a peroxide in the molecule, it has a drawback that it is easily decomposed by a trace amount of metal or impact. As described above, an initiator satisfying the above three conditions is extremely difficult in principle and synthesis.

As a result of earnest studies, the present inventor has found that the low-temperature initiating group initiates polymerization at a low temperature by adding a reducing agent, while the high-temperature initiating group is an azo-based initiating group that does not react with the reducing agent. The present inventors have completed the present invention by finding that a compound that initiates polymerization satisfies the above-mentioned three conditions and that this compound can be synthesized relatively easily.

[0007]

MEANS FOR SOLVING THE PROBLEMS The present invention provides "(1) an azo polymerization initiator having the halomethyl group represented by the general formula (1), the general formula (1)

[Chemical 2] (Wherein ^{R 1} is _{-CO-O-C m H 2m} -, - C n H
_{2n -CO-O-C m H} 2m - _or, -C _{n H} 2n -O
_{-CO-C m H 2m} - indicates, (n, m represents a natural number of 1 to 10), ^{R 2} represents an alkyl group of one prime number 1 to 5, Y is at least one or more halogen, Indicates a halomethyl group. (2) For an azo-based polymerization initiator having hydroxyl groups at both ends,
2. The method for producing an azo polymerization initiator according to item 1, wherein the carboxylic acid halide having a halomethyl group is reacted. (3) The method for producing an azo polymerization initiator according to item 1, wherein the azo polymerization initiator having a carboxylic acid halide at both ends is reacted with an alcohol having a halomethyl group. (4) A compound having an azo group in the main chain of a molecule obtained by causing a redox radical polymerization of an ethylenically unsaturated monomer by causing a reducing agent to act on the azo-based polymerization initiator having a halomethyl group according to the item 1. An azo group-containing polymer polymerization initiator composed of a united body. (5) A polymer having a halomethyl group at both ends or one end of a molecule obtained by radical thermal polymerization of an ethylenically unsaturated monomer using the azo-based polymerization initiator having a halomethyl group according to the item 1. A halomethyl group-containing polymer polymerization initiator composed of a united product. (6) The ethylenically unsaturated monomer is polymerized using one of the polymerization initiation groups with the polymerization initiator described in the item 1,
Next, a method for producing a block polymer, which comprises polymerizing another ethylenically unsaturated monomer using the other polymerization initiation group. (7) A block characterized by using the polymer polymerization initiator according to item 4 or 5 and polymerizing an ethylenically unsaturated monomer different from the monomer forming the polymer of the initiator. Method for producing polymer. Regarding

The azo-based polymerization initiator having a halomethyl group of the present invention (hereinafter sometimes referred to as a low molecular weight initiator) has a halomethyl group at both ends as a low temperature initiation group, and an azo as a high temperature initiation group. It has a group in the center of the molecule. This halomethyl group does not radically dissociate unless it comes into contact with a relatively strong reducing agent, such as a dithionite salt or a sulfinate salt, and in the absence of such a reducing agent, radical initiation does not actually occur below 200 ° C. On the other hand, in the presence of a strong reducing agent, 0-20
It starts redox easily even at ℃. The azo group is initiated by heat of 60 to 80 ° C., and the initiation temperature does not decrease or the initiation rate does not increase due to the presence of the reducing agent.

Therefore, the low molecular weight polymerization initiator of the present invention may be stored under a temperature condition where the high temperature initiating group can be protected so long as the reducing agent is avoided, and it is virtually inactivated when stored at 30 to 50 ° C. Since it is not present, it has good storage stability. The low-temperature initiation group of the low-molecular-weight initiator of the present invention means that it starts at a low temperature if a reducing agent is present, and does not mean that the group itself starts at a low temperature.

As a method for synthesizing a block copolymer using the low molecular weight initiator of the present invention, a reducing agent is allowed to act on a halomethyl group to redox-polymerize an ethylenically unsaturated monomer at a low temperature to form a main chain in the main chain. A polymeric initiator having an azo group is synthesized. A method of polymerizing other ethylenically unsaturated monomers using this polymer initiator. Or using azo group 60
The ethylenically unsaturated monomer is polymerized at a relatively high temperature of -80 ° C to synthesize a polymer initiator having a halomethyl group at one end and / or both ends. There are two types of methods for polymerizing other ethylenically unsaturated monomers using this polymer initiator, and either method may be used.

[0011]

The present invention will be described in detail below.

<Low-Molecular Polymerization Initiator of the Present Invention> The low-molecular polymerization initiator of the present invention is an azo-based initiator having a halomethyl group represented by the following general formula (1). General formula (1)

[Chemical 3] (Wherein ^{R 1} is _{-CO-O-C m H 2m} -, - C n H
_{2n -CO-O-C m H} 2m - _or, -C _{n H} 2n -O
_{-CO-C m H 2m} - indicates (n, m represents a natural number of 1 to 10), ^{R 2} represents an alkyl group of one prime number 1-5,
Y represents a halomethyl group having at least one halogen. )

Although n and m are 1 to 10, preferably 1 to 5 and more preferably 1 to 3 from the viewpoint of solubility. R ² is an alkyl group, and 1 to 3 is more preferable among 1 to 5 carbon atoms. Y is a halomethyl group, trihalomethyl or
Dihalomethyl is preferable, and trihalomethyl is particularly preferable. This is because the initiating ability increases as the number of halogens in the halomethyl group increases. At this time, halogens may be the same or different. Preferred types of halogen are chlorine, bromine and iodine, but chlorine and bromine are particularly preferred. This is because the initiation ability depends on the binding energy of the carbon-halogen element, and the above-mentioned halogen element is in the most preferable energy range. Specific examples of the initiator of the present invention include the following compounds.

[0014]

[Chemical 4]

[Chemical 5]

[Chemical 6]

[Chemical 7]

[Chemical 8]

[Chemical 9]

[Chemical 10]

[Chemical 11]

[Chemical 12]

[Chemical 13]

[Chemical 14]

[Chemical 15]

[Chemical 16]

[Chemical 17]

[Chemical 18]

[Chemical 19]

[Chemical 20]

[Chemical 21]

[Chemical formula 22]

[Chemical formula 23]

[Chemical formula 24]

[Chemical 25]

[Chemical formula 26]

[Chemical 27]

<Production Method> Any of the above-mentioned polymerization initiators of the present invention can be synthesized by an esterification reaction of a hydroxyl group and a carboxylic acid halide at a low temperature. Specifically, there are two types of manufacturing routes depending on the raw materials.

A method of reacting a carboxylic acid halide having a halomethyl group with an azo polymerization initiator having a hydroxyl group at both ends

A method of reacting an azo-based polymerization initiator having a carboxylic acid halide at both ends with an alcohol having a halomethyl group

Since the above reactions are the same kind of chemical reactions, the reaction conditions are the same. These reactions proceed quantitatively and a sufficient yield can be obtained at a ratio of equimolar alcohol to carboxylic acid halide, so it is not preferable which one is preferred in the reaction route itself, and the type of raw material It is appropriately selected depending on the performance of the intended polymerization initiator. Raw materials, production conditions, catalysts, etc. will be described below.

The azo-based polymerization initiator having hydroxyl groups at both ends, which is used as the (raw material), is represented by the following general formula (2). General formula (2)

[Chemical 28] (Here, m and R ² have the same meanings as in the general formula (1).)
In particular

[0020]

[Chemical 29]

[Chemical 30]

[Chemical 31]

[Chemical 32] Etc.

The carboxylic acid halide having a halomethyl group used in (1) is represented by the following general formula (3) or (4). Y-CO-X (3) (where Y represents the same meaning as in formula (1), and X represents a halogen element)

Specifically, CCl ₃ COCl, CCl ₃ C
OBr, CCl ₃ COI, CBr ₃ COCl, CBr ₃
COBr, CBr ₃ COI, HCCl ₂ COCl, HC
Cl ₂ COBr, HCCl ₂ COI, HCBr ₂ COC
1, HCBr ₂ COBr, HCBr ₂ COI, BrCC
l ₂ COCl, BrCCl ₂ COBr, BrCCl ₂ C
OI, ClCBr2COCl, ClCBr2COBr,
ClCBr2COI, and the like.

YC _n H _2n COX (4) (where n and Y have the same meanings as in general formula (1) and X has the same meaning as in general formula (3))

Specifically, CCl ₃ CH ₂ COCl, CC
l ₃ CH ₂ COBr, CCl ₃ CH ₂ COI, CBr ₃
CH ₂ COCl, CBr ₃ CH ₂ COBr, CBr ₃ C
H ₂ COI, CCl ₃ CH ₂ CH ₂ COCl, CCl ₃
CH ₂ CH ₂ COBr, CCl ₃ CH ₂ CH ₂ COI,
CBr ₃ CH ₂ CH ₂ COCl, CBr ₃ CH ₂ CH ₂
COBr, CBr ₃ CH ₂ CH ₂ COI, HCCl ₂ C
H ₂ COCl, HCCl ₂ CH ₂ COBr, HCCl ₂
CH ₂ COI, HCBr ₂ CH ₂ COCl, HCBr ₂
CH ₂ COBr, HCBr ₂ CH ₂ COI, BrCCl
₂ CH ₂ COCl, BrCCl ₂ CH ₂ COBr, Br
CCl ₂ CH ₂ COI, ClCBr ₂ CH ₂ COCl,
ClCBr ₂ CH ₂ COBr, ClCBr ₂ CH ₂ CO
I, etc. are mentioned.

The azo type polymerization initiator having a carboxylic acid halide at both terminals used in the above is represented by the following general formula (5). General formula (5)

[Chemical 33] (Here, m and R ² are general formula (1), and X is general formula (3).
Has the same meaning as. )

Specifically,

[Chemical 34]

[Chemical 35]

[Chemical 36]

[Chemical 37]

[Chemical 38]

[Chemical Formula 39]

[Chemical 40]

[Chemical 41]

[Chemical 42] Etc.

The halomethyl group-containing alcohol used in (1) is represented by the following general formula (6).

YC _n H _2n OH (6) (where n and Y have the same meanings as in the general formula (1))

Specifically, CCl ₃ CH ₂ OH, CBr ₃
CH ₂ OH, HCCl ₂ CH ₂ OH, HCBr ₂ CH ₂
OH, BrCCl ₂ CH ₂ OH, ClCBr ₂ CH ₂ O
H, CCl ₃ CH ₂ CH ₂ OH, CBr ₃ CH ₂ CH ₂
OH, HCCl ₂ CH ₂ CH ₂ OH, HCBr ₂ CH ₂
CH ₂ OH, BrCCl ₂ CH ₂ CH ₂ OH, ClCB
r ₂ CH ₂ CH ₂ OH, and the like.

(Production conditions) Reagents used in this reaction,
The solvent, gas, etc. must be sufficiently dried and dehydrated. This is because the carboxylic acid halide easily reacts with water to produce carboxylic acid and hydrochloric acid, and this carboxylic acid has a significantly lower reactivity with alcohol than the carboxylic acid halide, and as a result, the purity and yield of the target initiator are increased. Because it lowers the rate.

The reaction temperature for this reaction should be 30 ° C or more lower than the 10-hour half-life temperature of the azo initiator used. This is because, if the reaction is carried out at a temperature lower than this range, the decomposition of the azo group of the azo-based initiator to be used is practically not a problem. Specifically, the reaction temperature is preferably -10 ° C to 30 ° C, more preferably -5 ° C to 20 ° C. This reaction is preferably carried out in a low boiling point organic solvent having no hydroxyl group. This is because if it has a hydroxyl group, it reacts with the carboxylic acid halide contained in the raw material, and if it has a high boiling point, decomposition of the azo group occurs at the temperature at which the solvent is removed. As a preferred solvent,
Examples include lower hydrocarbons, lower halogenated hydrocarbons, aromatic hydrocarbons, ketones, ethers, and esters, and specific examples include n-heptane, n-hexane, cyclohexane, dichloromethane, chloroform, carbon tetrachloride, Dichloroethane, benzene, diethyl ether, tetrahydrofuran, acetone, methyl ethyl ketone, ethyl acetate and the like can be mentioned.

When the low molecular weight initiator is used as an initiator solution or an initiator dispersion, or a series of continuous steps of polymer initiator production or block copolymer production is performed in a solution or dispersion state. The solvent does not necessarily have to have a low boiling point because the dispersion medium is not removed in the process when it is carried out. These organic solvents may be used alone or in combination. In order to remove the reaction heat, it is preferable to use the same weight or more, more preferably twice the weight or more, based on the total weight of the raw materials.

(Catalyst) This reaction itself proceeds sufficiently without a catalyst, but amines and alkaline compounds may be used as a catalyst. Specifically, it is preferable to use triethylamine, trimethylamine, sodium hydroxide, potassium hydroxide or the like in an amount 0.1 to 2 times the mole of the raw material.

<Polymer Polymerization Initiator of the Present Invention> The present invention also relates to a polymer containing a polymerization initiation group, that is, a polymer polymerization initiator. The polymer polymerization initiator will be described below.

(Azo Group-Containing Polymer Initiator) As described above, the low molecular weight polymerization initiator of the present invention is an initiator containing a halomethyl group and an azo group. Polymerization having an azo group in the center of the molecule by causing a reducing agent to act on a halomethyl group while maintaining the azo group of the low molecular weight polymerization initiator of the present invention at a low temperature to polymerize an ethylenically unsaturated monomer An initiator can be obtained. Since this polymerization mechanism involves redox, it is generally called redox polymerization.

Reducing Agent Any reducing agent can be used as long as it can reduce the halogen element in the halomethyl group and is inert to the azo group. Examples thereof include dithionite salts, phosphinate salts, and amino compounds. Specifically, sodium dithionite, potassium dithionite, sodium phosphinate, calcium phosphinate, N, N-dimethyltoluidine, N , N-diethyltoluidine, and the like.
In each case, 0.01 mol per 1 mol of the low molecular weight initiator of the present invention
-10 mol is used. Since the low molecular weight initiator of the present invention is hydrophobic, when a hydrophilic dithionite salt or phosphinate salt is used as a reducing agent, 0.01 mol per mol of the initiator is used to promote mutual diffusion. It is advisable to use a phase transfer catalyst of -10 mol. Examples of the phase transfer catalyst include onium compounds and ionophores. Specifically, quaternary ammonium salts such as tetrabutylammonium bromide, tetrabutylammonium chloride, trioctylmethylammonium chloride and benzyltriethylammonium chloride, tetraphenylphosphonium chloride. , Tetrabutylphosphonium chloride,
Examples thereof include quaternary phosphonium salts such as trioctylethylphosphonium bromide, crown ethers such as 18-crown-6, azacrown, thiacrown and cryptand.

Ethylenically Unsaturated Monomer Any ethylenically unsaturated monomer may be used as long as it has a radically polymerizable ethylenic double bond. In the present invention, one or more of these monomers can be appropriately selected and used. Examples of the ethylenically unsaturated monomers used include (a) aromatic monovinyl monomers such as styrene,
p-chloromethylstyrene, o-aminostyrene, α-
(B) (meth) acrylic monomers such as methyl styrene,
For example, (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) acrylic acid n
-Butyl, i-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, i-octyl (meth) acrylate, (meth ) L-Methyl-heptyl acrylate, n-nonyl acrylate (meth), (meth)
Perfluoroethyl acrylate, hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, acrylonitrile, methacrylonitrile, (meth) acrylamide, etc., (c) vinyl halides such as vinyl chloride, (d) halogenation Vinylidene, such as vinylidene chloride, etc., (e) Others, such as vinyl acetate, isobutylene, vinylidene cyanide, vinylpyrrolidone, vinyl pyridine, N-vinylcarbazole, methyl vinyl ketone, vinyl isocyanate, maleic anhydride, N-substituted maleimide, etc. Can be given. Further, a macromonomer having one radical-polymerizable vinyl group in one molecule and having a main chain composed of styrene, (meth) acrylic acid ester, polysiloxane and the like can also be mentioned. In addition, "(meth) acryl" described in the present specification is a general term for acryl and methacryl, respectively.

Polymerization Polymerization using the low-molecular initiator of the present invention is possible in any reaction mode as long as the above-mentioned polymerization mechanism is carried out. That is, any of bulk polymerization, liquid polymerization, suspension polymerization, dispersion polymerization, emulsion polymerization and the like may be used. In particular, when a phase transfer catalyst is used, it is preferable to use water or a polar solvent such as alcohol, dimethylformamide or dimethylsulfoxide in a certain amount or more in order to promote ionic dissociation. In particular, water is the most preferable medium in terms of hygiene, ease of post-treatment, cost and the like. That is, specifically, it is preferable to disperse the low-molecular initiator and the ethylenically unsaturated monomer of the present invention in an aqueous solvent, that is, water alone or a mixture of a water-soluble polar solvent and water, and perform polymerization. .. At this time, it is preferable to use a medium of the same amount or more as the weight of the ethylenically unsaturated monomer used,
Particularly, about 2 to 5 times is preferable.

Even if air is used as the polymerization atmosphere, it does not significantly hinder the polymerization, but it is preferable to use an inert gas such as nitrogen, argon or carbon dioxide. The polymerization temperature depends on the stability of the azo group in the initiator of the present invention used, but is generally preferably 0 to 30 ° C. A halogen-free dispersion aid such as polyvinyl alcohol, sodium polyacrylate, or a surfactant can be used in the polymerization. In order to prevent cross-linking and control the molecular weight, a halogen-free molecular weight modifier, a halogen-free chain transfer agent such as n-butyl mercaptan, α-methylstyrene dimer and the like can be used. The low molecular weight initiator of the present invention is 0.01 to 100 parts by weight of the ethylenically unsaturated monomer in the same manner as a general polymerization initiator.
10 parts by weight, more preferably 0.1 to 5 parts by weight is used. If it is less than this range, the polymerization yield is low, and if it exceeds this range, the amount of unreacted initiator remaining cannot be ignored.
In this way, a polymer polymerization initiator having an azo group in its main chain is obtained.

(Halomethyl Group-Containing Polymer Initiator) While maintaining the halomethyl group of the low molecular weight initiator of the present invention, the azo group is radically dissociated by heat, and the ethylenically unsaturated monomer is polymerized to obtain both terminals. Alternatively, a polymer polymerization initiator having a halomethyl group at one end can be obtained. This mechanism is a very common radical thermal polymerization.

Ethylenically Unsaturated Monomer The same monomer as the ethylenically unsaturated monomer described in the above section (azo group-containing polymer initiator) can be used.

Polymerization Since this is a very general thermal polymerization, any polymerization method used for thermal polymerization can be used. That is, bulk polymerization, solution polymerization, suspension polymerization, dispersion polymerization, emulsion polymerization and the like. The polymerization temperature is preferably about 10 hours half-life temperature or higher of the initiator of the present invention to be used. Specifically, the initiator of the present invention is used at 40 to 150 ° C, more preferably 60 to 100 ° C. The polymerization atmosphere, the amount of the initiator of the present invention and the medium with respect to the ethylenically unsaturated monomer are the same as the conditions described in the above section (Azo group-containing polymer initiator). Further, a dispersion aid, a molecular weight modifier and a chain transfer agent used in general thermal polymerization can also be used. To protect the halomethyl group, do not bring anything with a reducing action into the system.

<Production of Block Copolymer> Since there are two types of polymer initiators obtained by using the initiator of the present invention, an azo group-containing polymer initiator and a halomethyl group-containing polymer initiator, a block copolymer is used. There are also two types of polymer production routes.

Method Using Azo Group-Containing Polymer Initiator Polymerizing an ethylenically unsaturated monomer different from the monomer constituting the polymer initiator by using the azo group-containing polymer itself as a thermal polymerization initiator A block copolymer can be obtained by For the polymerization using the polymer initiator, the above-mentioned (halomethyl group-containing polymer initiation is used for the ethylenically unsaturated monomer, polymerization mode, polymerization temperature, polymerization atmosphere, dispersion aid, molecular weight modifier, and chain transfer agent to be used. The conditions are the same as those described in the section of the agent), and an azo group-containing polymer polymerization initiator may be used instead of the low molecular weight polymerization initiator. However, the amount of the polymeric initiator used is 1/9 to 9, preferably 1/4 to 4 of the ethylenically unsaturated monomer. This is because the block copolymer obtained outside this range cannot sufficiently exhibit the properties as a block copolymer.

Method Using Halomethyl Group-Containing Polymer Initiator An ethylenically unsaturated monomer different from the monomer constituting the polymer initiator by causing a reducing agent to act on the halomethyl group-containing polymer initiator itself. A block copolymer can be obtained by polymerizing.

For the polymerization using the polymer initiator, for the reducing agent, the ethylenically unsaturated monomer, the polymerization mode, the polymerization atmosphere, the dispersion aid, the molecular weight adjusting agent, and the chain transfer agent, see (azo group-containing polymer initiator). In the same manner as the conditions described in the section 1), a halomethyl group-containing polymer polymerization initiator may be used instead of the low molecular weight polymerization initiator. In this step, since there is virtually no azo group in the polymer initiator and there is no need to protect it,
The polymerization temperature does not need to be low, and 0 to 150 ° C., preferably 30 to 100 ° C. is used. However, the amount of the polymer initiator used is preferably in the same range for the same reason as in the case of using the azo group-containing polymer initiator.

The block copolymer of the present invention is produced by a method of producing a polymer polymerization initiator and using the initiator to produce a block copolymer, as well as the production of the polymer polymerization initiator and the block copolymer. It is also possible to continuously produce the polymer. There are two possible routes for continuously producing a high molecular weight polymerization initiator and a block copolymer using the low molecular weight polymerization initiator of the present invention.

(1) First Step Radical thermal polymerization of an ethylenically unsaturated monomer is carried out using the azo group of the low molecular weight polymerization initiator of the present invention to produce a halomethyl group-containing polymer initiator. Second Step Subsequently, an ethylenically unsaturated monomer different from that in the previous radical ripening polymerization step is introduced, sufficiently impregnated with a polymer initiator, and redox radical polymerization is performed to obtain a block copolymer.

(2) First Step Redox radical polymerization of an ethylenically unsaturated monomer is carried out using the trihalomethyl group of the low molecular weight polymerization initiator of the present invention to produce an azo group-containing polymer initiator. Second Step Subsequently, an ethylenically unsaturated monomer different from the one used in the previous redox radical polymerization step is introduced, the polymer initiator is sufficiently impregnated, and radical thermal polymerization is carried out to obtain a block copolymer.

In the method (2), the reducing agent, the phase transfer catalyst and the like used for carrying out the redox radical polymerization can have the effect of inhibiting the polymerization of the polymerization or inhibiting the polymerization. The method (1) is industrially preferable because it must be used.

Specifically, the first step is solution polymerization using a dispersion medium, suspension polymerization, dispersion polymerization, or emulsion polymerization, in which radical thermal polymerization of ethylenically unsaturated monomer is carried out, and trihalogenation is carried out. A methyl group-containing polymer initiator solution or dispersion is prepared. At this time, the polymerization temperature, the polymerization atmosphere, the amount of the initiator and the medium of the present invention with respect to the ethylenically unsaturated monomer are the same as the conditions described in the section of the halomethyl group-containing polymer. The conditions for the dispersion aid, the molecular weight modifier, and the chain transfer agent are the same as those described in the section of the halomethyl group-containing polymer initiator.

Next, as the second step, redox radical polymerization is carried out in the same polymerization apparatus with an ethylenically unsaturated monomer different from the monomer used when producing the polymer polymerization initiator. As the second step, specifically, sufficient for the polymer initiator in the polymer initiator solution or dispersion,
The monomer is impregnated, and after that, the reducing agent is allowed to act to carry out redox radical polymerization. The impregnation time is
Although it varies depending on the composition, molecular weight, crystallinity, monomer used, type and amount of the dispersion medium of the polymer initiator, it is usually 2
It requires 0.5 to 30 hours in the temperature range of 0 to 80 ° C.
Redox radical polymerization using the polymer initiator is a reducing agent, an ethylenically unsaturated monomer, a polymerization temperature, a polymerization atmosphere,
The dispersion aid, the molecular weight modifier, and the chain transfer agent are preferably in the same range for the same reason as described in the section "Method using a halomethyl group-containing polymer initiator". In addition,
In the second step, it is preferable to add a dispersion medium which is the same as or different from the dispersion medium used in the first step. In this case, the total weight of the dispersion medium is preferably equal to or more than the weight of the block copolymer produced, and particularly preferably about 2 to 5 times.

[0053]

EXAMPLES Next, the present invention will be specifically described with reference to Examples.

Example 1 Ice water was added, and a stirrer was placed in a water bath maintained at 0 ° C.
A 500 ml separable flask equipped with a nitrogen introducing capillary tube and a condenser is installed. 100 g of dehydrated chloroform in the separable flask, 2,
9.81 g of 2-azobis (2-cyanopropanol) and 10.12 g of triethylamine were charged, and a trichloroacetyl cloid 9.0.2 g was introduced while introducing a slight amount of nitrogen gas.
A solution prepared by dissolving 09 g in 100 g of dehydrated chloroform is added in a dropping funnel in about 1 hour. After that, the reaction is carried out at 15 ° C for 1 hour and further at 30 ° C for 1 hour. The reaction solution is placed in a separating funnel (11), and 200 g of pure water is added and washed with water. The same washing with water is repeated twice more, and the mixture is evaporated to dryness with a rotary evaporator at room temperature. As a result, 8.95g
A brown viscous liquid was obtained. The result of elemental analysis is chlorine 43.7.
The content was 11.5% by weight of nitrogen, 13.1% by weight of oxygen, 29.6% by weight of carbon and 2.1% by weight of hydrogen. This is designated as initiator A.

Example 2 14.45 g of 2,2-azobis (2-cyanopentanoic chloride) was used in place of 2,2-azobis (2-cyanopropanol), and trichloroethanol 7 was used in place of trichloroacetyl chloride. The same operation as in Synthesis Example 1 was performed except that 0.42 g was used. As a result, 9.05
g of a brown viscous liquid was obtained. As a result of elemental analysis, chlorine 39.
2 wt%, nitrogen 10.3 wt%, oxygen 11.8 wt%,
The carbon content was 35.4% by weight and the hydrogen content was 3.3% by weight. This is designated as initiator B.

Example 3 In a water bath equipped with a temperature controller, a 500 ml separable flask equipped with a stirrer, a capillary tube for introducing nitrogen and a condenser is installed. In this separable flask, 100 g of methyl methacrylate, 200 g of toluene,
Then, 1.6 g of the initiator A is charged, polymerization is carried out at 70 ° C. for 4 hours while introducing a slight amount of nitrogen, and further polymerization is carried out at 80 ° C. for 4 hours. The reaction solution was precipitated in 3 Kg of hexane,
After the filtration, the solid content was dried for 10 hours in a vacuum dryer kept at 80 ° C. As a result, a polystyrene-equivalent number average molecular weight (Mn) of 32,000 by gel permeation chromatography (GPC) and the same weight average molecular weight (Mw) of 6
94.8 g of 5,000 polymethylmethacrylate were obtained. This is Polymer A.

Example 4 The same operation as in Example 3 was carried out except that styrene was used instead of methyl methacrylate. As a result, Mn of polystyrene conversion by GPC was 33,000 and Mw was 66.5.
93.1 g of polystyrene No. 00 was obtained. This is designated as Polymer B.

Example 5 The same operation as in Example 3 was performed except that 1.8 g of the initiator B was used instead of the initiator A. As a result, Mn of polystyrene conversion by GPC was 32,000 and Mw was 65,50.
94.5 g of polymethylmethacrylate of 0 was obtained. This is Polymer C.

Example 6 A separable flask similar to that used in Example 3 was charged with 100 g of methyl methacrylate, 1.6 g of initiator A, 200 g of pure water, 8 g of sodium phosphinate hydrate, and 3.2 g of tetrabutylammonium bromide. Polymerization is carried out at 30 ° C. for 8 hours while introducing nitrogen. The reaction dispersion was filtered, the solid content was washed with water, rinsed with methanol, and then dried in a vacuum dryer kept at 30 ° C. for 20 hours. As a result, Mn in terms of polystyrene by GPC
Of 43,000 and Mw of 88,000 to obtain 95.2 g of polymethylmethacrylate. This is designated as Polymer D.

Example 7 The same operation as in Example 6 was carried out except that styrene was used instead of methyl methacrylate. As a result, Mn of polystyrene conversion by GPC was 46,000 and Mw was 93.0.
94.8 g of polystyrene of 00 was obtained. This is designated as Polymer E.

Example 8 Polymer A5 was placed in a separable flask similar to that used in Example 3.
0 g, 50 g of styrene and 200 g of pure water are charged, and the monomer is impregnated into the polymer at 70 ° C. for 3 hours while introducing a slight amount of nitrogen. Then sodium phosphinate hydrate 8 g tetrabutylammonium bromide 3.2 g
Is added and polymerization is further carried out at 70 ° C. for 5 hours. Reaction dispersion
After being filtered, the solid content was washed with water, rinsed with methanol, and then dried in a vacuum dryer kept at 80 ° C. for 10 hours. As a result, Mn in terms of polystyrene by GPC
Is 71,000 and Mw is 145,000 and the copolymer 9 is
5.8 g was obtained. The blocking rate was 65.3% by weight when the blocking rate was determined by a method of sequentially extracting and separating this copolymer with acetonitril and cyclohexane (extracting and separating method).

Example 9 The same operation as in Example 8 was carried out except that polymer B was used instead of polymer A, and methyl methacrylate was used instead of styrene. As a result, M converted to polystyrene by GPC
Copolymer 9 having n of 73,000 and Mw of 148,000
6.6 g was obtained. According to the extraction separation method, the blocking rate is 6
It was 6.3% by weight.

Example 10 The same operation as in Example 8 was carried out except that the polymer C was used in place of the polymer A. As a result, Mn of polystyrene conversion by GPC was 72,000 and Mw was 148,000.
95.5 g of a copolymer of According to the extraction separation method, the blocking rate was 64.2% by weight.

Example 11 Polymer D5 was placed in a separable flask similar to that used in Example 3.
0 g, styrene 50 g, and pure water 200 g are charged, and the monomer is impregnated into the polymer at 30 ° C. for 3 hours while introducing a slight amount of nitrogen. After that, it is polymerized at 70 ° C. for 3 hours and further at 80 ° C. for 2 hours. Filter the reaction dispersion,
The solid content was washed with water, rinsed with methanol, and then dried in a vacuum dryer kept at 80 ° C. for 10 hours. As a result, the Mn in terms of polystyrene by GPC was 70,0.
00, 95.2 g of a copolymer having an Mw of 143,000 was obtained. According to the extraction separation method, the blocking rate is 66.5% by weight.
Met.

Example 12 The same operation as in Example 11 was carried out except that polymer E was used instead of polymer D and methyl methacrylate was used instead of styrene. As a result, M converted to polystyrene by GPC
Copolymer 9 having n of 73,000 and Mw of 148,000
6.0 g was obtained. According to the extraction separation method, the blocking rate is 6
It was 7.0% by weight.

Example 13 In a water bath equipped with a temperature controller, a 1-liter separable flask equipped with a stirrer, a capillary tube for introducing nitrogen and a condenser is installed. Into this separable flask, 100 g of styrene, 200 g of pure water, and 1.6 g of initiator A were charged, and while introducing a slight amount of nitrogen, the mixture was heated to 4 at 70 ° C.
Polymerization is carried out for an hour, and further at 80 ° C. for 4 hours. Subsequently, with stirring, 200 g of pure water is added, and further 100 g of methyl methacrylate is added to impregnate the polymer with the monomer at 70 ° C. for 2 hours. Thereafter, 16 g of sodium phosphinate monohydrate and 6.4 g of tetrabutylammonium bromide are added, and polymerization is carried out at 70 ° C. for 5 hours. The reaction dispersion was filtered, the solid content was washed with water, rinsed with methanol, and then dried with a vacuum dryer kept at 80 ° C for 10 minutes.
Allowed to dry for hours. As a result, 193.5 g of a copolymer having a polystyrene-converted Mn of 73,100 Mw of 149,000 by GPC was obtained. According to the extraction separation method, the blocking rate was 64.4% by weight.

[0067]

INDUSTRIAL APPLICABILITY The initiator of the present invention is stable to heat and impact at about 30 ° C., and a block polymer can be easily synthesized using an ethylenically unsaturated monomer.

Claims (7)

[Claims] 1. An azo-based polymerization initiator having a halomethyl group represented by the general formula (1), represented by the general formula (1): (Wherein ^{R 1} is _{-CO-O-C m H 2m} -, - C n H
_{2n -CO-O-C m H} 2m - _or, -C _{n H} 2n -O
_{-CO-C m H 2m} - indicates (n, m represents a natural number of 1 to 10), ^{R 2} represents an alkyl group of one prime number 1-5,
Y represents a halomethyl group having at least one halogen. ) 2. The method for producing an azo polymerization initiator according to claim 1, wherein an azo polymerization initiator having hydroxyl groups at both ends is reacted with a carboxylic acid halide having a halomethyl group. 3. The method for producing an azo polymerization initiator according to claim 1, wherein an azo polymerization initiator having a carboxylic acid halide at both ends is reacted with an alcohol having a halomethyl group. 4. An azo group in the main chain of a molecule obtained by reacting an azo polymerization initiator having a halomethyl group according to claim 1 with a reducing agent to redox radically polymerize an ethylenically unsaturated monomer. An azo group-containing polymer polymerization initiator comprising a polymer having 5. A halomethyl group at both ends or one end of a molecule obtained by radical thermal polymerization of an ethylenically unsaturated monomer using the azo-based polymerization initiator having a halomethyl group according to claim 1. A halomethyl group-containing polymer polymerization initiator comprising a polymer having 6. An ethylenically unsaturated monomer is polymerized with one of the polymerization initiating groups using the polymerization initiator according to claim 1, and then the other polymerization initiating group is used with another. A method for producing a block polymer, which comprises polymerizing an ethylenically unsaturated monomer. 7. The polymer polymerization initiator according to claim 4 or 5 is used to polymerize an ethylenically unsaturated monomer different from the monomer forming the polymer of the initiator. And a method for producing a block polymer.