JPH11269216A - Preparation of living polymer of styrene-based derivative - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a styrene-based derivative having a controlled molecular weight distribution by an industrially advantageous method. SOLUTION: A monomer represented by the formula (wherein X represents hydrogen atom or methyl group, Y represents a -(CH2 )n C1 at meta or para position, and n is an integer of 1-6) is polymerized using a polymerization catalyst comprising an iodine compound having at least one bond selected from a carbon-iodine bond, a hydrogen-iodine bond and a halogen-iodine bond, and a radical polymerization initiator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a styrene derivative living polymer, and more particularly to a method for producing a styrene derivative living polymer containing a chloro group having a narrow molecular weight distribution.

[0002]

2. Description of the Related Art A chloro group attached to a benzene ring or an alkyl group can be converted into a functional group such as an amino group, a carboxyl group, an alkoxysilyl group, or an aldehyde group through a Grignard reaction. Further, they can be easily converted to a hydroxyl group or a quaternary ammonium salt through these. If such a highly reactive chloro group can be incorporated into a polymer molecule in a controlled manner, a reactive polymer with functionality can be obtained by converting the chloro group into various functional groups. it is conceivable that.

As one of the methods, there is a living polymerization technique of a monomer containing an alkylchloro group. A typical example of such a living polymerization method is an anion polymerization method. Using an anionic polymerization method, the living polymerization of α-methylstyrene derivative and α-methylstyrene with a chloromethyl group at the meta or para position,
A method for synthesizing a random copolymer having a narrow molecular weight distribution and providing a resist material having excellent radiation sensitivity has been disclosed (JP-A-57-109943).

[0004] In addition to such alkylchloro groups, many techniques for producing living polymers of functional group-substituted styrene derivatives by anionic polymerization have been proposed.
However, the anionic polymerization method must be carried out in a form excluding oxygen and water from the system, and is difficult to operate and requires dangerous initiator reagents, so that it is limited to a small batch reactor, Difficult to apply to industrial production.

Further, the monomers and solvents used are:
It must be of high purity with thorough removal of water, and is more expensive than radical polymerization methods that do not require such purification. Therefore, a radical polymerization method that is easier to handle, can be synthesized at low cost, and can control the molecular weight distribution, that is, a living radical polymerization method, is desired.

[0006] As one of such radical polymerization methods, a polymerization method using an iniferter has been reported [Makrom.
ol. Chem., Bulletin, 3,127 (150982)]. However,
The use of iniferters has the following two disadvantages. The first point is that the polymerization rate is slow, and there is a report that the polymerization conversion rate is about 40% after a reaction time of 20 hours. Second, the free radical trap, which stabilizes the terminus of the growing chain, has the ability to initiate new chains, creating new chains during the polymerization process, resulting in polydispersion of the resulting polymer (eg, SRTuner, RWBlevinsPolymer).
Reprints, 29 (2) September 1988). Therefore, it was not suitable for producing a polymer having a narrow molecular weight distribution.

Further, 2,2,6,6-tetramethyl-1
A living polymerization method of styrene using a stable nitroxy radical represented by piperidinyloxy (TEMPO) for polymer terminal stabilization has been reported by Georges et al. (JP-A-6-199916). However, this polymerization method requires a high polymerization temperature of 120 ° C., and is not applicable to monomers having a thermally unstable functional group. Further, TEMPO, which is a stable nitroxy radical, is relatively expensive, which is disadvantageous in terms of cost.

Regarding the precise control of the primary structure of the styrene monomer, for example, JP-A-7-126322 discloses
There is a description that a polymer having a relatively narrow molecular weight distribution can be obtained in the presence of an iodine compound having a carbon-iodine bond and a radical polymerization initiator. However, there is no description about a styrene-substituted product containing a functional group, and there is a description of a comparative example that polymerization controllability is applied to p-chlorostyrene having a chloro group at the p-position. It is said that it cannot be controlled. Further, in the above reported examples, the obtained polymer cannot be obtained with a very high molecular weight, and a long polymerization time of several tens of hours is required to obtain a polymer having a conversion of 50% or more.

Apart from the above, there are also reports on living radical polymerization of vinyl acetate in the presence of an iodine compound.

[0010]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above problems, and is intended to produce a styrene derivative containing a functional group having a controlled molecular weight distribution by an industrially advantageous method. Provide a way.

[0011]

Means for Solving the Problems The present inventor can control the living polymerization of a monomer having an electron resonance effect, which is intermediate between styrene and vinyl acetate, and designs a reaction via a substituted styrene containing a chloro group. For example, as a result of intensive studies considering that polymerization of chloro group-substituted styrene is also possible, the electron resonance effect of the monomer can be controlled by using the following styrene-based derivative, and a specific iodine compound can be converted into a normal radical polymerization system. By adding
The inventors have found that the molecular weight of the obtained polymer is narrow, and have reached the present invention.

In the method for producing a living polymer of a styrene derivative according to the present invention, the monomer represented by the general formula (1) is formed by bonding at least one bond selected from a carbon-iodine bond, a hydrogen-iodine bond and a halogen-iodine bond. The polymerization is characterized by using an iodine compound having at least one iodine compound and a polymerization catalyst comprising a radical polymerization initiator.

[0013]

Embedded image

In the formula, X represents a hydrogen atom or a methyl group;
Y is attached to the meta or para position - (CH ₂₎ shows the _n Cl, n is an integer of 1-6.

In the general formula (1), when n is 0, the chloro group is a monomer directly added to the meta-position or para-position of styrene, so that the vinyl group has a strong electron resonance effect and the living polymerization is controlled. If n becomes larger than 6, the polymerization rate becomes slow due to steric hindrance of the monomer, and the practicality becomes poor. Therefore, n is limited to 1 to 6.

As the monomer (substituted styrene) represented by the above general formula (1), for example, m, p-chloromethyl-styrene, m, p- (2-chloroethyl) -styrene, m, p- ( 3-chloropropyl) -styrene, m,
p- (4-chlorobutyl) -styrene, m, p-chloromethyl-α-methylstyrene, m, p- (2-chloroethyl) -α-methylstyrene, m, p- (3-chloropropyl) -α- Examples include, but are not limited to, methylstyrene, m, p- (4-chlorobutyl) -α-methylstyrene, and the like. Among these, p- (chloromethyl) -styrene, p- (chloromethyl) -α-methylstyrene and p-chlorostyrene are preferred.

The iodine compound used in the present invention includes a compound having at least one bond selected from a carbon-iodine bond, a hydrogen-iodine bond and a halogen-iodine bond.

Examples of the compound having a carbon-iodine bond include alkyl iodide, perfluoroalkyl iodide, an adduct of hydrogen iodide and an alkene, and phenyl iodide.

Examples of the alkyl iodide include iodomethane, iodoethane, iodopropane, iodobutane, diiodomethane, 1,2-diiodoethane, iodoform, chloroiodomethane, iodoacetonitrile, iodoacetic acid and the like. Examples of the perfluoroalkyl iodide include iodoperfluoropropane, 1-iodoperfluorohexane, 1-iodoperfluorooctane, 1,2-diiodoperfluoroethane, 1,4-diiodoperfluorobutane, 1,6-
And diiodoperfluorohexane.

Examples of the alkene used in the adduct of hydrogen iodide and the alkene include vinyl ester monomers such as vinyl acetate, various vinyl ether monomers such as isobutyl vinyl ether, and styrene monomers. Examples of the phenyl iodide include iodobenzene, 2-iodoethylbenzene, and the like. Examples of the synthesis of the adduct of hydrogen iodide and an alkene include, for example, a method of mixing anhydrous hydrogen iodide with an alkene at a low temperature.

Examples of the compound having a hydrogen-iodine bond include hydrogen iodide. The above halogen-
Examples of the compound having an iodine bond include iodine monochloride, iodine trichloride, iodine monobromide and the like.

As the above iodine compound, iodoform,
Alkyl iodides such as diiodomethane and iodoacetonitrile; perfluoroalkyl iodides such as 1-iodoperfluorohexane, 1,4-diiodoperfluorobutane and 1,6-diiodoperfluorohexane; hydrogen iodide and alkene Adducts: hydrogen iodide and the like are preferable. Furthermore, the use of iodoform is particularly preferred because the calculated value of the number average molecular weight, which is assumed to form one polymer molecule from one molecule of iodoform added to the polymerization, and the measured value most accurately.

The above iodine compounds may be used alone or in combination of two or more.

The amount of the iodine compound used can be appropriately determined according to the molecular weight of the living polymer to be obtained. However, when the amount is small, the structure of the living polymer cannot be controlled. Therefore, the amount is preferably 0.0001 to 0.2 mol, more preferably 0.0002 to 0.1 mol, per 1 mol of the monomer.

The method of adding the iodine compound is not particularly limited, but it is preferable that the iodine compound is added to the polymerization system before the start of the polymerization.
It is preferable from the viewpoint of control of molecular weight distribution and simplicity of operation.

Examples of the method for the radical polymerization reaction include use of a usual radical polymerization initiator; use of a photopolymerization initiator and irradiation of light; irradiation of radiation, laser light, light, and the like; heating, and the like.

Particularly, it is preferable to use a radical polymerization initiator industrially, and the type of the polymerization initiator is that which can generate a radical and react with a vinyl ester monomer or an iodine compound to initiate polymerization. There is no particular limitation, and it can be selected from compounds that generate radicals by the action of heat, light, radiation, an oxidation-reduction chemical reaction, or the like.

Examples of the radical polymerization initiator include azo compounds, organic peroxides, inorganic peroxides, organometallic compounds, and photopolymerization initiators. More specifically, azo compounds such as azobisisobutyronitrile (AIBN), azobisisobutyrate, and hyponitrite; benzoyl peroxide (BPO), lauroyl peroxide;
Organic peroxides such as dicumyl peroxide and dibenzoyl peroxide; inorganic peroxides such as potassium persulfate and ammonium persulfate; hydrogen peroxide-ferrous iron, BPO
Redox polymerization initiators such as -dimethylaniline-based and cerium (IV) salt-alcohol-based. Among these, AIBN and BPO are preferably used.

In the case of photopolymerization, a photopolymerization initiator such as an acetophenone type, a benzoin ether type, or a ketal type may be added.

The above radical polymerization initiators may be used alone or in combination of two or more as long as they do not adversely affect the progress of polymerization due to interaction. Further, a combination in which the polymerization is advanced to some extent by the action of heat and then the polymerization is completed by light may be used.

The amount of the radical polymerization initiator used is not particularly limited as long as the polymerization can be started, but is preferably in the range of 0.02 to 20 mol per mol of the iodine compound, 0.000 for
It is preferably from 0.5 to 0.5 mol. If the amount of the radical polymerization initiator is too small, polymerization is slow and the polymerization rate is low, which is industrially disadvantageous. When used in excess, control of the reaction may be difficult.

More preferably, it is in the range of 0.05 to 10 mol per mol of iodine compound, and 0.0001 to 0.2 mol per mol of monomer. Furthermore, it is particularly preferable to use the radical polymerization initiator in the range of 0.1 to 5 mol per 1 mol of the iodine compound.

The polymerization temperature varies depending on the type of the radical polymerization reaction, and is not particularly limited. However, the polymerization is preferably carried out at a temperature of -30 ° C to 120 ° C, more preferably 0 ° C to 100 ° C. ° C.

The reaction is usually carried out at normal pressure, but it is also possible to increase the pressure.

As the polymerization method used in the present invention, conventionally known polymerization methods can be used, for example, bulk, solution, suspension, emulsion polymerization and the like are used. In particular, from the viewpoint of suppressing the chain transfer to obtain a better controlled living polymer, bulk polymerization is preferably used. In addition, continuous polymerization using an extruder can also be used.

As the solvent for the solution polymerization, alcohols, toluene, benzene, and other commonly used solvents can be used. Particularly, in the polymerization of vinyl ester monomers, the chain transfer constant is relatively small, and Use of benzene is particularly preferred because of its excellent properties.

It has been confirmed that most of the starting terminals of the living polymer obtained according to the present invention are alkyl groups, perfluoroalkyl groups, phenyl groups and the like derived from iodine compounds, and that most of the growing terminals are iodine. I have. Therefore, by using an iodine compound having a functional group in the main polymerization, a functional group can be introduced into the terminal of the living polymer. It is also possible to convert to another functional group by utilizing the reactivity of the terminal functional group or iodine. These terminal functional polymers can be used as macromonomers, used as crosslinking points, compatibilizers, raw materials for block polymers, and the like.

The molecular weight distribution (Mw / Mn) of the living polymer obtained in the present invention is more controlled than that obtained by a conventional ordinary radical polymerization method.
9 Further, it is possible to obtain a living polymer having a narrower molecular weight distribution of 1.05 to 1.8.

The molecular weight of the living polymer of the present invention can be adjusted by the amount of the iodine compound, but is suitable for obtaining a living polymer having a number average molecular weight of 300 to hundreds of thousands, particularly, a number average molecular weight of 1 to 100,000. It is suitable for obtaining 1,000 to 200,000 living polymers.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be specifically described based on examples and comparative examples.

Example 1 In a 50 ml flask purged with nitrogen, 0.115 g (0.7 mmol) of AIBN, 0.275 g (0.7 mmol) of iodoform, and 10.0 g (66 mmol) of p- (chloromethyl) -styrene were charged. After the container was sealed and uniformly mixed, the mixture was heated to 80 ° C. to start polymerization. After polymerizing for 7 hours, the temperature was reduced to 0.
C. to terminate the polymerization. After 7 hours of polymerization, the polymerization conversion was 91%. The obtained polymer solution was poured into a large amount of methanol to precipitate a product. After drying this n
The polymer was purified by reprecipitation with hexane and dried under vacuum to obtain a polymer.

Example 2 18 g of p-chloromethyl-α-methylstyrene was used instead of p- (chloromethyl) -styrene, and 1,6- was used instead of 0.275 g of iodoform.
0.554 g of diiodoperfluorohexane (1.0 m
mol)), polymerization and polymer purification were carried out according to Example 1 to obtain a polymer. The polymerization conversion rate after 7 hours was 87%.

Example 3 The amount of AIBN used was 0.36
Polymerization and polymer purification were carried out according to Example 1 except that the amount was changed to 0 g (2.2 mmol) to obtain a polymer.
After 7 minutes, the polymerization conversion was 96%.

Example 4 0.46 g of 1-iodoperfluorohexane instead of 0.275 g of iodoform
Polymerization and polymer purification were carried out according to Example 1 except that (1.3 mmol) was used to obtain a polymer. After 7 hours, the polymerization conversion was 85%.

Comparative Example 1 Polymerization and purification of a polymer were carried out in the same manner as in Example 1 except that 10.0 g of p-chlorostyrene was used instead of p- (chloromethyl) -styrene to obtain a polymer. The polymerization conversion after 7 hours was 91%.

Comparative Example 2 A polymer was obtained by polymerization and polymer purification according to Example 1 except that no iodoform was used. After 7 hours, the polymerization conversion was 92.
%Met.

The polymerization conversion, number average molecular weight (Mn), and weight average molecular weight (Mw) of the polymers obtained in the above Examples and Comparative Examples were measured and are shown in Table 1.

(1) Polymerization conversion conversion was measured by gas chromatography (GC) using n-heptane as an internal standard. The GC used was Shimadzu Corporation, and the column used was "PEG 1500". (2) Molecular Weight The molecular weight of the polymer was measured by gel permeation chromatography (GPC) in terms of standard polystyrene. For the measurement, THF was used as an eluent, and the flow rate was 1 ml /
In min, a refractometer was used for detection. GPC has S
A “column: KF-80M × 2 pcs” manufactured by HODEX was used. The molecular weight distribution (Mw / Mn) was calculated from the measured values of the number average molecular weight (Mn) and the weight average molecular weight (Mw).

Unless otherwise noted, monomers, solvents, etc. were used in columns (Aldrich “Inhibitor Remover, dis
After removing the polymerization inhibitor by p. column "), the mixture was used after deoxygenation treatment.

[0050]

[Table 1]

The components used in the table are as follows.・ DIPFH: 1.6-diiodoperfluorohexane ・ IPFH: 1-iodoperfluorohexane ・ ClMeSt: p- (chloromethyl) -styrene ・ ClMe─MeSt: p- (chloromethyl) -α-methylstyrene ・ ClSt : P-chlorostyrene

[0052]

According to the present invention, a living polymer of a styrene derivative containing a chloro group can be obtained by polymerizing under a condition that the polymerization temperature is mild without requiring purification of a monomer or a solvent. In addition, the living polymer can be converted into a block polymer by further polymerizing another monomer onto the living polymer, and can be applied to various materials such as a dispersant, a sizing agent, and a surface modifier. It is.

Claims (1)

[Claims] 1. A monomer represented by the general formula (1) comprising an iodine compound having at least one bond selected from a carbon-iodine bond, a hydrogen-iodine bond and a halogen-iodine bond, and a radical polymerization initiator. A method for producing a styrenic derivative living polymer, characterized in that the polymerization is carried out using a polymerization catalyst. Embedded image [In the formula, X represents a hydrogen atom or a methyl group, Y represents-(CH ₂ ) _n Cl attached to the meta or para position, and n represents 1 to
6 represents an integer)