JPH09291070A - New azoamide compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject new compound having high-temperature activity, excellent in solubility to an organic solvent, having high melting point and high capability of polymerization, and useful as a polymerization initiator. SOLUTION: This compound is an azoamide compound of formula I (R1 and R2 are each an independent lower alkyl; R3 is >=2C saturated alkyl) and e.g. 2,2'-azobis(N-cyclohexyl-2-methylpropionamide) is exemplified. The compound of formula I is obtained by reacting an azodicarboxylate compound of formula II (R4 is a lower alkyl) with an amine compound of formula III in a suitable solvent or without any solvent and in the presence of an alkaline organic metal compound. For instance, the compound in the concrete example is obtained by mixing cyclohexylamine with dimethyl 2,2'-azobis(2-methylpropionate) and reacting, after dropping a mathanol solution containing 28% sodium methoxide under stirring.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an oil-soluble and high temperature active azo compound useful as a polymerization initiator and the like.

[0002]

2. Description of the Related Art Azo compounds and organic peroxides are known as organic radical polymerization initiators. Organic peroxides are generally unstable with respect to impact, heating, etc., and undergo self-induced decomposition and the like, and have the risk of fire and explosion.
On the other hand, the azo compound has an advantage that it is easy to control the polymerization reaction because it is relatively stable physically and chemically despite its high activity.
There is a demand for azo polymerization initiators having various activities depending on the purpose. In particular, there is a demand for an azo-based polymerization initiator having high-temperature activity when treating a residual monomer when polymerizing styrene, or when performing cross-linking polymerization.

Examples of the azo-based polymerization initiator having high temperature activity include 1,1-azobis (1-cyanocyclohexane) and 2,
2'-Azobis (2,4,4-trimethylpentane) and the like are known. However, since 1,1-azobis (1-cyanocyclohexane) has a cyano group in the molecule, there is a possibility that toxicity due to this cyano group may be expressed, or 2,2′- Azobis (2,4,4-trimethylpentane)
Has a problem that it has a melting point around room temperature and is inconvenient to handle.

Many amide type azo compounds generally have high-temperature activity. For example, 2,2'-azobis (2-methylpropionamide) and 2,2'-azobis (2-methyl-N-methyl). -Propionamide) and 2,2'-azobis [2-methyl-N
-(Hydroxymethyl) -propionamide] etc.
8288, Makromol. Chem., 193 2843 (1992), JP-A-2
All of the known azoamide compounds described in JP-A-149551, etc. are water-soluble, and therefore when the polymerization of an oil-soluble monomer is desired to be carried out by solution polymerization, the solubility is poor in an organic solvent used as a solvent, and It has a problem that it is difficult to use for the polymerization reaction. Therefore, an azoamide compound which is oil-soluble and has high temperature activity has been desired. For the purpose of improving such a point, 2,2'-azobis (2-methyl-N-allyl-propionamide) in which an allyl group is introduced into an amino group has been reported (JP-A-2-149551). Gazette). However, although the activation temperature was somewhat improved, the polymerization reaction was stopped by chain transfer of the allyl group during the polymerization reaction, so that a large amount had to be added, and improvement in this respect was also desired.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and provides a novel azoamide compound having high temperature activity, excellent solubility in an organic solvent, and a high melting point. With the goal.

[0006]

The present invention provides a compound represented by the general formula [1]:

[0007]

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(Wherein R ₁ and R ₂ each independently represents a lower alkyl group, and R ₃ represents a saturated alkyl group having 2 or more carbon atoms).

Further, the present invention is an invention of a method for polymerizing a monomer, which comprises using the above-mentioned azoamide compound.

Furthermore, the present invention is an invention of a polymerization initiator comprising the above-mentioned azoamide compound.

The azoamide compound represented by the above general formula [1] of the present invention is, for example, the general formula [2]

[0012]

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(In the formula, R ₄ represents a lower alkyl group, and R ₁
And R ₂ are the same as above. ) And an azodicarboxylic acid diester compound represented by the general formula [3]

[0014]

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It can be obtained by reacting an amine compound represented by the formula (in the formula, R ₃ is the same as above) with or without a solvent in the presence of an alkaline organometallic compound.

In the general formulas [1] and [2], the lower alkyl group represented by R ₁ and R ₂ may be linear, branched or cyclic and has, for example, a carbon number. 1 to 6 alkyl groups, specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl Group, tert-pentyl group,
Examples thereof include a 1-methylpentyl group, an n-hexyl group, an isohexyl group, a cyclopropyl group, a cyclopentyl group and a cyclohexyl group. In the general formulas [1] and [3], the saturated alkyl group having 2 or more carbon atoms represented by R ₃ may be linear, branched or cyclic, and specifically, Ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group,
Pentyl group, isopentyl group, tert-pentyl group, 1-methylpentyl group, n-hexyl group, isohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, hexadecyl group, octadecyl group,
Examples thereof include a cyclopropyl group, a cyclopentyl group and a cyclohexyl group, and among them, a saturated alkyl group having 2 to 10 carbon atoms, preferably 2 to 6 carbon atoms, and more preferably 3 to 6 carbon atoms. In the general formula [2], the lower alkyl group represented by R ₄ may be linear or branched, and examples thereof include an alkyl group having 1 to 6 carbon atoms. Is methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, ter
Examples thereof include t-butyl group, sec-butyl group, pentyl group, isopentyl group, tert-pentyl group, 1-methylpentyl group, n-hexyl group and isohexyl group.

Examples of the alkaline organometallic compound used in producing the azoamide compound of the present invention include alkali metal alkoxides such as sodium methoxide, sodium ethoxide, potassium methoxide, potassium ethoxide, potassium tert-butoxide, and the like. For example, n-
Examples include organic lithium compounds such as butyl lithium and tert-butyl lithium.

As the reaction solvent, for example, hydrocarbons such as toluene, xylene, benzene, cyclohexane, n-hexane and n-octane, for example, methanol,
Ethanol, n-propanol, isopropanol, n-
Examples include alcohols such as butanol, isobutanol, tert-butanol, dimethylformamide, dimethylsulfoxide, and the like. These may be used alone or in combination of two or more.

The amounts of the azodicarboxylic acid diester compound and the amine compound used in the production of the azoamide compound of the present invention vary depending on the kind of the amine compound used, but the amine compound is usually added to the azodicarboxylic acid diester compound. 1.5 to 10 times mol, preferably 2 to 5
It is appropriately selected from the range of the molar amount.

Although the amount of the alkaline organometallic compound used varies depending on the kind of the amine compound, it is usually 0.05 to 3 with respect to the azodicarboxylic acid diester compound.
It is appropriately selected from the range of equivalents, preferably 0.1 to 0.5 equivalents.

The reaction temperature is not particularly limited, but if it is too high, the azo group decomposes, and if it is too low, the reaction rate slows down and it takes time for production. Therefore, it is usually appropriately selected from the range of 0 to 40 ° C. The reaction time varies depending on the type of azodicarboxylic acid diester compound or amine compound, but is usually 1
It is appropriately selected from the range of 24 hours.

The azodicarboxylic acid diester compound and amine compound according to the present invention may be either commercially available products or manufactured products.

The azoamide compound of the present invention can be effectively used as a polymerization initiator or a foaming agent because the azo group is easily decomposed by heating or irradiation with light to generate a nitrogen gas and a radical species. At that time, if various monomers are present, polymerization is promptly caused.

To polymerize or copolymerize monomers using the azoamide compound of the present invention as a polymerization initiator,
For example, it may be performed as follows. That is, the azoamide compound obtained as described above and the monomer may be subjected to a polymerization reaction in an appropriate solvent or without a solvent, if necessary, in an inert gas atmosphere according to a conventional method. Post-treatment after the reaction may be carried out in accordance with a post-treatment method generally used in this field.

Examples of the monomer include α-olefinic aromatic hydrocarbons having 8 to 20 carbon atoms such as styrene, 4-methylstyrene, 4-ethylstyrene and divinylbenzene.
For example, vinyl formate, vinyl acetate, vinyl propionate,
Vinyl ester having 3 to 20 carbon atoms such as isopropenyl acetate and the like, halogenated vinyl compounds having 2 to 20 carbon atoms such as vinyl chloride, vinylidene chloride, vinylidene fluoride, tetrafluoroethylene and tetrachloroethylene, such as acrylic acid and methacryl Acid, itaconic acid, maleic acid,
3 to 3 carbon atoms such as fumaric acid, crotonic acid, citraconic acid, mesaconic acid, vinyl acetic acid, allyl acetic acid, and vinyl benzoic acid
20 α, β-ethylenically unsaturated carboxylic acids (these acids may be in the form of a salt such as an alkali metal salt such as sodium or potassium or an ammonium salt), for example, methyl methacrylate, methacryl Ethyl acid, propyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate,
Methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, lauryl methacrylate, stearyl acrylate, methyl itaconate, ethyl itaconate, methyl maleate, ethyl maleate, methyl fumarate, ethyl fumarate, Α, β-ethylenically unsaturated carboxylic acid esters having 4 to 20 carbon atoms such as methyl crotonate, ethyl crotonate, methyl citraconic acid, ethyl citraconic acid, methyl mesaconic acid, ethyl mesaconate, and methyl 3-butenoate. For example, cyanovinyl compounds having 3 to 20 carbon atoms such as acrylonitrile, methacrylonitrile, and allyl cyanide, and vinyl amide compounds having 3 to 20 carbon atoms such as acrylamide and methacrylamide.
For example, the carbon number of acrolein, crotonaldehyde, etc. is 3
~ 20 α, β-ethylenically unsaturated aldehydes, such as vinyl sulfonic acid, 4-vinylbenzene sulfonic acid, and other vinyl sulfonic acids having 2 to 20 carbon atoms (these acids are alkali metal salts such as sodium and potassium) Etc., such as vinylamine, allylamine, etc., vinyl aliphatic amines having 2 to 20 carbon atoms, such as vinylaniline, etc., vinyl aromatic amine having 8 to 20 carbon atoms. C5-C20 vinyl aliphatic heterocyclic amines such as N-vinylpyrrolidone and vinylpiperidine, and C5-C20 vinyl aromatic heterocyclic amines such as vinylpyridine and 1-vinylimidazole Such as allyl alcohol, crotyl alcohol and the like, α, β-ethylenically unsaturated alcohols having 3 to 20 carbon atoms, such as 4-vinylphenol and the like. Olefin phenols prime 8-20, such as butadiene, diene compounds having 4 to 20 carbon atoms such as isoprene and the like.
These may be used alone or in combination of two or more.

When carrying out the polymerization reaction, a chain transfer agent (for example, lauryl mercaptan, octyl mercaptan, butyl mercaptan, 2-mercaptoethanol, butyl thioglycolate, etc.) is added, if necessary, to control the molecular weight. You can go.

Examples of the method of the above polymerization reaction include solution polymerization, bulk polymerization, suspension polymerization, emulsion polymerization and the like. At this time, the azoamide compound of the present invention and an ordinary radical polymerization initiator (for example, azobisisobutyronitrile, 2,2 '
-Dimethyl azobisisobutyrate, etc.) may be used in combination.

Examples of the solvent used in the solution polymerization include ethers such as tetrahydrofuran, diethyl ether and dioxane, halogenated hydrocarbons such as chloroform, methylene chloride and 1,2-dichloroethane, n-hexane,
Hydrocarbons such as petroleum ether, toluene, benzene and xylene, alcohols such as methanol, ethanol and isopropanol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, acetonitrile, N,
Examples thereof include N-dimethylformamide and dimethyl sulfoxide. These solvents may be used alone or in any suitable combination of two or more kinds.

The polymerization reaction is also preferably carried out in an inert gas atmosphere. Examples of the inert gas include a nitrogen gas and an argon gas.

The ratio of the azoamide compound of the present invention to the monomer used in the above-mentioned polymerization reaction varies depending on the kind of the compound of the present invention to be used, but it can be generally selected from a wide range, and is usually based on the monomer. It is appropriately selected from the range of 0.01 to 100% by weight, preferably 0.05 to 50% by weight.

The concentration of the monomer during the polymerization reaction varies depending on the kind of the monomer, but is usually 5 to 100% by weight.
(No solvent), preferably selected appropriately in the range of 10 to 60% by weight.

The polymerization temperature is not particularly limited, but if it is too low, the progress of the polymerization slows down because the decomposition of the azo group is small, and if it is too high, the decomposition of the azo group becomes excessively large and it becomes difficult to control the polymerization, so that it is usually 20 to 20. It is appropriately selected from the range of 150 ° C, preferably 50 to 130 ° C. Since the azoamide compound of the present invention has a high temperature activity, it can be effectively used even in a polymerization reaction at a high temperature, for example, 90 to 150 ° C, more practically 90 to 120 ° C. .

The polymerization reaction time varies depending on the reaction conditions such as the reaction temperature, the type of the azoamide compound and the monomer to be reacted, the concentration, etc., but is usually appropriately selected from the range of 2 to 24 hours. Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[0034]

【Example】

Example 1.2 Synthesis of 2,2'-azobis (N-cyclohexyl-2-methylpropionamide) 47.3 g of cyclohexylamine and 50 g of dimethyl 2,2'-azobis (2-methylpropionate) were mixed and mixed with this. 28% methanol solution of sodium methoxide under stirring 2
After dropping 0 g, the mixture was reacted with stirring at room temperature for 6 hours. After standing overnight, 100 ml of water was added to the reaction solution and then cooled to 10 ° C. to precipitate crystals. This is collected by filtration, dried and the desired 2,2 '
59.4 g (yield 81%) of yellow crystals of -azobis (N-cyclohexyl-2-methylpropionamide) were obtained. The solubility is shown in Table 1. mp 116 ° C. ¹ H-NMR δppm (CDCl ₃ ): 1.2 to 2.0 (m, 20H, cyclohexyl group), 1.33 (s, 12H, = NC (C H ₃ ) ₂ ), 3.87 (m, 2H, cyclohexyl group (NH-C) H )), 6.7 (br, 2H, CON H ). IR (KBr tablet) ν cm ^-1 : 3344 (NH), 1645 (C = O).

Example 2.2 Synthesis of 2,2'-azobis [N- (2-methylpropyl) -2-methylpropionamide] Isobutylamine 34.9 g and 2,2'-azobis (2-methylpropionate) After mixing 50 g, 10 g of 28% methanol solution of sodium methoxide was added dropwise with stirring to this,
The mixture was reacted with stirring at room temperature for 6 hours. After leaving it overnight, water is added to the reaction solution.
After adding 100 ml, the mixture was cooled to 10 ° C. to precipitate crystals.
This is collected by filtration, dried and the desired 2,2'-azobis [N- (2
56.4 g (yield 83%) of pale yellow crystals of -methylpropyl) -2-methylpropionamide] were obtained. The solubility is shown in Table 1. mp 100 ° C. _{^{1 H-NMR δppm (CDCl 3}} ): 0.92 (m, 12H, CH (C H 3) 2),
1.35 (s, 12H, = NC (C H ₃ ) ₂ ), 1.82 (m, 2H, C H (CH ₃ ) ₂ ),
3.2 (m, 4H, NH- C H 2), 6.9 (br, 2H, CON H). IR (KBr tablet) ν cm ^-1 : 3336 (NH), 1660 (C = O).

Example 3 Synthesis of 2,2'-azobis (N-butyl-2-methylpropionamide) 34.9 g of n-butylamine and 50 g of 2,2'-azobis (2-methylpropionate) were mixed. Then, 10 g of 28% methanol solution of sodium methoxide was added dropwise thereto with stirring, and the mixture was reacted with stirring at room temperature for 6 hours. After leaving it overnight, water 1
After adding 00 ml, the mixture was cooled to 10 ° C. to precipitate crystals. This is collected by filtration, dried and the target light yellow crystal of 2,2'-azobis [N-butyl-2-methylpropionamide] 58.0 g
(Yield 85.5%) was obtained. The solubility is shown in Table 1. mp 65 ° C. ¹ H-NMR δppm (CDCl ₃ ): 0.94 (t, 6H, CH ₂ C H ₃ ), 1.3
~ 1.6 (m, 8H, C H ₂ C H ₂ ), 1.34 (s, 12H, = NC (C H ₃ ) ₂ ), 3.
5 (m, 4H, NH- C H 2), 6.85 (br, 2H, CON H). IR (KBr tablet) ν cm ⁻¹ : 3331 (NH), 1660 (C = O).

Example 4.2 Synthesis of 2,2'-azobis [N- (2-methylethyl) -2-methylpropionamide] 28.2 g isopropylamine and 2,2'-azobis (2-methylpropionate) 50 g was mixed, 20 g of 28% methanol solution of sodium methoxide was added dropwise thereto with stirring, and the mixture was reacted with stirring at room temperature for 6 hours. After standing overnight, 100 ml of water was added to the reaction solution and then cooled to 10 ° C. to precipitate crystals. This is collected by filtration, dried and the target 2,2'-azobis is obtained.
41.5 g (yield 67%) of pale yellow crystals of [N- (2-methylethyl) -2-methylpropionamide] were obtained. The solubility is shown in Table 1. mp 103 ° C. _{^{1 H-NMR δppm (CDCl 3}} ): 1.8 (d, 12H, CH (C H 3) 2),
1.33 (s, 12H, = NC (C H ₃ ) ₂ ), 4.15 (m, 2H, NH-C H (C
H ₃ ) ₂ ), 6.85 (br, 2H, CON H ). IR (KBr tablet) ν cm ^-1 : 3388 (NH), 1664 (C = O).

Example 5 2,2'-Azobis (N-hexyl-2-
Synthesis of methyl propionamide) 28.2 g of n-hexylamine and 50 g of 2,2'-azobis (2-methylpropionate) were mixed, and 20 g of a 28% methanol solution of sodium methoxide and 10 ml of methanol were mixed with this while stirring. Sequential additions were made and the reaction was allowed to stir at room temperature for 6 hours. After standing overnight, add 100 ml of water to the reaction mixture, then n-hexane
Extracted with 100 ml. The hexane layer was washed with water and then dried over anhydrous sodium sulfate. Evaporate the solvent to obtain the desired
2,2'-azobis (N-hexyl-2-methylpropionamide)
76.3 g (yield 95%) of a yellow semi-molten crystal was obtained. The solubility is shown in Table 1. ¹ H-NMR δppm (CDCl ₃ ): 0.88 (m, 6H, CH ₂ C H ₃ ), 1.3
( M , 12H, NH-CH ₂ CH ₂ C H ₂ C H ₂ C H ₂ CH ₃ ), 1.34 (s, 12H, = NC
(C H ₃ ) ₂ ), 1.55 (m, 4H, NH-CH ₂ C H ₂ CH ₂ CH ₂ CH ₂ CH ₃ ), 3.35
( M , 4H, NH-C H ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₃ ), 6.85 (br, 2H, CON
H ). IR (KBr tablet) ν cm ⁻¹ : 3340 (NH), 1647 (C═O).

Example 6. Synthesis of 2,2'-azobis (N-propyl-2-methylpropionamide) 28.3 g of n-propylamine and 50 g of 2,2'-azobis (2-methylpropionate) were mixed. , While stirring, 10 ml of methanol and 28% methanol solution of sodium methoxide
10 g were sequentially added, and the mixture was reacted with stirring at room temperature for 6 hours. After standing overnight, 100 ml of water was added to the reaction solution and then cooled to 5 ° C. to precipitate crystals. This is collected by filtration, dried and the desired 2,
54.0 g (yield 87%) of slightly yellow crystals of 2'-azobis (N-propyl-2-methylpropionamide) were obtained. The solubility is shown in Table 1. mp 65 ° C. ¹ H-NMR δppm (CDCl ₃ ): 0.94 (t, 6H, -NH-CH ₂ CH ₂ C
_{H 3), 1.34 (s,} 12H, = NC (C H 3) 2), 1.57 (m, 4H, NH-CH 2 C
H ₂ CH ₃ ), 3.32 (q, 4H, NH-C H ₂ CH ₂ CH ₃ ), 6.85 (br, 2H, CO
N H ). IR (KBr tablet) ν cm ^-1 : 3335 (NH), 1653 (C = O).

Example 7 Synthesis of 2,2'-azobis (N-ethyl-2-methylpropionamide) 2,2'-azobis (2-methylpropionate) (50 g) and methanol (50 ml) were mixed with ethylamine. 39 g of the hydrochloride was added and suspended, and 133 g of a 28% methanol solution of sodium methoxide was added dropwise at 5 ° C., and the mixture was stirred at room temperature for 6 hours for reaction. After standing overnight, 200 ml of water was added to the reaction solution, and then methanol was distilled off under reduced pressure to precipitate crystals. After cooling to 5 ° C, the crystals are collected by filtration and dried to give the target 2,2'-azobis (N-ethyl-2-methylpropionamide) pale yellow crystals.
16.6 g (yield 30%) was obtained. The solubility is shown in Table 1. mp 98 ° C. ¹ H-NMR δ ppm (CDCl ₃ ): 1.18 (t, 6H, NH-CH ₂ C H ₃ ,),
1.34 (s, 12H, = NC (C H ₃ ) ₂ ), 3.39 (m, 4H, NH-C H ₂ CH ₃ ), 6.8
(Br, 2H, CON H ). IR (KBr tablet) ν cm ⁻¹ : 3394 (NH), 1667 (C═O).

Comparative Example 1.2 Synthesis of 2,2'-azobis (N-methyl-2-methylpropionamide) 2,2'-azobis (2-methylpropionate) 50 g and 40%
37.1 g of methylamine in methanol was mixed and stirred with 28% methanol solution of sodium methoxide.
10 g was added, and the mixture was reacted with stirring at room temperature for 7 hours. After standing overnight, it was cooled to 5 ° C. to precipitate crystals. This is filtered off,
After drying, 37.2 g (yield: 75%) of the target 2,2′-azobis (N-methyl-2-methylpropionamide) pale yellow crystal was obtained. The solubility is shown in Table 1. mp 153 ° C. ¹ H-NMR δppm (CDCl ₃ ): 1.35 (s, 12H, = NC (C
_{H 3) 2), 2.92 (} s, 6H, NH-C H 3), 6.9 (br, 2H, CON H). IR (KBr tablet) ν cm ⁻¹ : 3393 (NH), 1665 (C═O).

[0042]

[Table 1] *) Solubility of each azoamide compound in 100g of solvent at 25 ℃.

As the polymerization initiator, those having a solubility of 2% or more, preferably 5% or more are highly practical, and from the results shown in Table 1, all of the azoamide compounds of the present invention undergo a polymerization reaction using an organic solvent. It turns out that it is suitable for.
On the other hand, 2,2′-azobis (N-methyl-2-methylpropionamide) obtained in Comparative Example 1 has a low solubility in ethyl acetate and toluene, and the polymerization reaction using such a solvent It turns out that it is not practical to use.

Experimental Example 1. Half-life test Each 1% of the azoamide compounds obtained in Examples 1 to 7 (W /
W) Prepare an ethylbenzene solution, measure the concentration of the azoamide compound in each sample for each unit time in a thermostatic bath at a predetermined temperature, determine the decomposition rate constant at each temperature, and decompose it. From the rate constant, according to the Arrhenius equation,
The 10-hour half-life temperature of each azoamide compound was calculated. Table 2 shows the results.

[0045]

[Table 2]

From the above results, since the 10-hour half-life temperatures are all around 110 ° C., it can be seen that all of the azoamide compounds of the present invention have high temperature activity.

Experimental Example 2 The azoamide compound obtained in Example 1, 3 or 6 was treated with 4 ×
5 ml of each styrene solution containing 10 ⁻⁴ mol / l was charged into a glass ampoule, deaerated, and then sealed under reduced pressure. 110
Each ampoule was placed in a constant temperature bath adjusted to ° C to start polymerization, and the ampule was taken out of the constant temperature bath at regular intervals and immediately cooled in ice water to stop the polymerization. Next, the polymerization solution of the ampoule was put into methanol to precipitate a polymer. This was collected by filtration, dried under reduced pressure at 60 ° C. for 8 hours, and the obtained polymer amount was measured. The polymerization rate was determined from the amount of styrene at the time of charging and the amount of generated polymer. The results are shown in Table 3.

[0048]

[Table 3]

As is clear from Table 3, the oil-soluble azoamide compound according to the present invention has a high polymerization activity in the polymerization of styrene.

[0050]

INDUSTRIAL APPLICABILITY As described above, the present invention provides a novel azoamide compound having high temperature activity, excellent solubility in organic solvents, high melting point, and high polymerization ability. It has a remarkable effect.

Claims (3)

[Claims] 1. A compound of the general formula [1] (In the formula, R ₁ and R ₂ each independently represent a lower alkyl group, and R ₃ represents a saturated alkyl group having 2 or more carbon atoms.) An azoamide compound. 2. A method for polymerizing a monomer, which comprises using the azoamide compound according to claim 1. 3. A polymerization initiator comprising the azoamide compound according to claim 1.