JP3179869B2 - Method for producing graft copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel method for producing a (meth) acrylate-based graft copolymer having a regulated molecular structure.

[0002]

2. Description of the Related Art Block copolymers and graft copolymers have been developed for the purpose of enhancing the functionality and performance of polymer materials. Recently, polymerizable functional groups have been added to one end. With the progress of the technology for synthesizing oligomers and polymers (macromonomers) having these, attention has been drawn to the development and application of graft copolymers using these. Various methods have been proposed to date for synthesizing macromonomers. For example, the anionic polymerization method of Milkovich et al.
7-21486, JP-A-50-116586, etc.) and a radical polymerization method of ICI (Japanese Patent Publication No. 43-112).
No. 24, JP-B-43-16147), radical copolymerization (US Pat. No. 3,689,593) by Du Pont, and GTP (group transfer polymerization) method by Toa Gosei Chemical Industries (JP-A-62-62801).

[0003] However, the above-mentioned anionic polymerization method involves:
The (meth) acrylic acid ester monomer has a disadvantage that its application is difficult. In the radical polymerization method, the obtained macromonomer contains bifunctional components caused by side reactions such as termination of recombination in the synthesis process, and when used in the production of a graft copolymer, its moldability due to simultaneous crosslinking reaction Was low. GTP method is (meta)
It is suitable for the synthesis of macromonomer using acrylic acid ester, and the purity of the obtained macromonomer is high. In these respects, it is superior to other methods. However, since the synthesis reaction of the initiator for synthesizing the macromonomer is a multi-stage reaction and the yield is low (about 10 to 20%), it cannot be said that it is sufficient as an industrial production method. In addition, depending on the copolymerization reactivity ratio between the polymerizable vinyl group and the comonomer of the macromonomer, distribution of the composition of the graft copolymer often occurs, and it is not easy to obtain a graft copolymer having a regulated structure. Was. Furthermore, the polymerization of macromonomers and comonomers often has low solubility of macromonomers in comonomers, and it is difficult to increase the molecular weight of the backbone polymer by frequently used solution radical polymerization. Was. As described above, in the method for producing a graft copolymer using these macromonomers, it has been difficult to obtain a graft copolymer having a regulated molecular structure in accordance with the molecular design.

On the other hand, as a reaction for synthesizing a methacrylic resin and a copolymer thereof, the above-mentioned GTP method has been described by Du Pont
No. 58-13605, USP 44143
Nos. 72, 4417034, 4508880, and 4524196. However, they disclose a method for synthesizing the above-described macromonomer or block copolymer, but do not disclose a method for synthesizing the graft copolymer.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to select a polymer compound constituting the trunk of the graft copolymer and a (meth) acrylate component constituting the branch from a wide range, To provide a novel method for producing a (meth) acrylate-based graft copolymer having a controlled chain length and a branched chain length in a high yield.

[0006]

The gist of the present invention is to provide a polymer compound having at least one unit represented by the following general formula (I) in a molecular chain in substantially absence of water. Used as an initiator in the presence of a Lewis acid or H
^{_{F 2 -, (CH 3)}} 3 SiF 2 - graft and performing a source of anion selected from a compound the presence of at least one (meth) living polymerization of acrylic acid esters ^- and F In the method for producing the copolymer.

[0007]

Embedded image (In the formula, R represents hydrogen or an alkyl group having 1 to 6 carbon atoms, and R 'represents an alkyl group having 1 to 12 carbon atoms.)

[0008]

In the present invention, the polymer compound used as an initiator (hereinafter, referred to as a polymer initiator) is not particularly limited as long as it has at least one unit represented by the general formula (I) in a molecular chain. It is not something to be done. The polymer initiator preferably has two or more units represented by the general formula (I) in the molecular chain.

The polymer initiator is obtained by reacting a metal compound such as lithium diisopropylamide with a polymer compound having one or more acrylate units in a molecular chain (hereinafter referred to as a polymer initiator material), It can be produced by extracting the α-proton of the acrylate portion and then reacting it with a silylating agent such as trimethylsilyl chloride, but is not necessarily limited to this method. Lithium diisopropylamide as a metalating agent can be prepared, for example, by reacting n-butyllithium with diisopropylamine at 0 ° C. As a silylating agent, in addition to trimethylsilyl chloride, tri-n-butylsilyl chloride,
T-butyldimethylsilyl chloride, hexamethyldisilazane, hexaethyldisilazane, hexaiso-butyldisilazane, hexat-butyldisilazane and the like are preferably used. The raw material of the polymer initiator is not particularly limited,
Examples include polyacrylate, methacrylate-acrylate copolymer, ethylene-acrylate copolymer, and the like, and various polymer initiator materials can be used depending on the purpose.

The molecular weight of the high molecular initiator is not particularly limited, either, but the number average molecular weight is 1000 to 100.
About 0000 is preferable. If the number average molecular weight is less than 1,000, the mechanical properties of the obtained graft copolymer tend to decrease, and if it exceeds 1,000,000, the moldability tends to decrease. The polymerization method and polymerization conditions for the raw material of the polymer initiator can be any known techniques. For example, besides ordinary solution radical polymerization, if high molecular weight is required, emulsion polymerization, suspension polymerization, bulk polymerization, etc. may be used, and if molecular weight and molecular weight distribution control are required, living methods such as anionic polymerization may be used. By using the polymerization method, it is possible to control the polymer structure of the polymer initiator raw material constituting the trunk portion of the graft copolymer to a high degree.

R in the general formula (I) may be hydrogen or an alkyl group having 1 to 6 carbon atoms, and is preferably a methyl group in view of the availability of raw materials. Although an alkyl group having 7 or more carbon atoms may be used, it is not common in that it is difficult to obtain. R 'may be an alkyl group having 1 to 12 carbon atoms, but is preferably an alkyl group having 1 to 4 carbon atoms from the viewpoint of easy availability of raw materials. Although an alkyl group having 13 or more carbon atoms may be used, it is not suitable because it is difficult to obtain and the reactivity tends to decrease.

The (meth) acrylate used in the living polymerization of the present invention can be selected arbitrarily according to the purpose. Examples thereof include methyl (meth) acrylate and ethyl (meth) acrylate. , (Meth) acrylic acid n
-Butyl, octyl (meth) acrylate, dodecyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2, methacrylate Examples thereof include 3,3-tetrafluoropropyl, benzyl (meth) acrylate, phenyl (meth) acrylate, allyl (meth) acrylate, glycidyl (meth) acrylate, and trimethylsilyl (meth) acrylate. In the present invention, α, β may be added to the (meth) acrylate according to the purpose.
-(Meth) of a polyfunctional group having two or more unsaturated vinyl groups
Acrylic esters can also be added.

In the present invention, the chain length of the (meth) acrylic acid ester polymer which is a branch portion of the graft copolymer obtained by living polymerization is determined by the unit represented by the formula (I) in the polymer initiator. Can be controlled by the molar ratio of the (meth) acrylate monomer to the This molar ratio is not particularly limited, but may be 10
It is preferably in the range of 10,000 to 10,000. If it is less than 10, the mechanical properties tend to decrease, and if it is more than 10,000, the moldability tends to decrease.

The compound used as a catalyst in the living polymerization of the present invention is a Lewis acid when the monomer used for the polymerization is an acrylate ester, whereas HF ₂ ^- or (CH _{3) 3} SiF ₂ ^- and F ^- compound serving as a source of anions selected from the preferred. Examples of Lewis acids include ZnCl ₂ , ZnBr ₂ , Z
In addition to zinc halides such as nI ₂ , compounds such as mono- or dialkylaluminum halides and dialkylaluminum oxides can be mentioned. Of these, zinc halides are preferred. The amount of the Lewis acid present in the reaction system is 5 to 2% of the monomer used for living polymerization.
About 0 mol% is preferable. ^{_{HF 2 -, (CH 3)}} 3 SiF
₂ ^- and F ^- Representative examples of sources become compounds of anion selected ^{_{from, HF 2 -; (CH 3}} ) 3 Si
F ₂ ^- tris dimethylamino sulfonium salt (hereinafter, T
AS salt), that is, TAS ⁺ HF ₂ ⁻ , TAS ⁺
Examples include (CH ₃ ) ₃ SiF ₂ ⁻ ; and tetrabutylammonium fluoride [(C ₄ H ₉ ) ₄ N ⁺ F ⁻ ], and TAS ⁺ (CH ₃ ) ₃ SiF ₂ ^- is most preferred. The amount of the compound serving as the anion supply source in the reaction system is preferably about 0.1 to 50 mol% based on the starting site (unit represented by the general formula (I)).

The polymerization reaction for synthesizing the graft copolymer in the present invention can be carried out without a solvent, but is generally preferably carried out in a suitable solvent. Examples of suitable solvents when a Lewis acid is used as a catalyst include chlorinated hydrocarbon solvents such as dichloromethane and 1,2-dichloroethane, toluene, xylene, tetralin and the like. Solvents that react with Lewis acids such as tetrahydrofuran are not suitable. Examples of a suitable solvent when a compound serving as a source of an anion is used as a catalyst include tetrahydrofuran, toluene, xylene, tetralin, acetonitrile, and the like. Halogenated hydrocarbon solvents such as methylene chloride and chloroform are not preferred. When these solvents are used, they must be sufficiently dehydrated and purified according to a conventional method. When a solvent with insufficient dehydration and purification is used, the polymerization of the (meth) acrylic ester does not become living polymerization, and the intended graft copolymer cannot be obtained. Similarly, the reaction must be carried out in a sufficiently dehydrated and purified inert gas or under a high vacuum.

In the graft copolymer of the present invention, the (meth) acrylate polymer segment constituting the branch is synthesized by living polymerization. Therefore, this segment can be further made into a block copolymer. For example, first, butyl methacrylate is polymerized using a polymer initiator, and then methyl methacrylate is added and polymerized, and the graft is made of a block copolymer of polybutyl methacrylate and polymethyl methacrylate. A copolymer is formed.

The synthesis of the graft copolymer in the present invention can be carried out in a temperature range of -100 ° C to 100 ° C. A more preferred temperature range is -80C to 60C.

In the present invention, the graft copolymer can be controlled to have a desired molecular structure according to the purpose and application. For example, when high transparency and weather resistance are required, it is preferable to use a copolymer composed of an acrylic ester and a methacrylic ester as the raw material of the polymer initiator. Alternatively, when high impact strength, high elongation is required, or when the properties as an elastomer are required, a polyacrylate having a glass transition temperature of 0 ° C. or less is used as a starting material for the polymer initiator. It is preferable to select a suitable rubbery polymer compound and select a polymer having a glass transition temperature of 40 ° C. or higher for a (meth) acrylate polymer serving as a branch portion of a graft copolymer obtained by living polymerization. Thus, according to the present invention, a graft copolymer having various regulated molecular structures can be easily synthesized.

[0019]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not necessarily limited thereto.

The evaluation of various physical properties in the examples was carried out by the following methods. The tensile modulus, tensile strength at break, and elongation at break were based on ASTM D-638. Light transmittance was based on ASTM D-1003. However, the measurement was made for the one having a thickness of 3.2 mm. The weather resistance was evaluated by the rate of change in elongation after exposure to a sunshine weatherometer for 1000 hours. Dinstat impact strength is DIN-
53453. In the examples, the amount of the initiator site (expressed in mol) was expressed by regarding one unit represented by the general formula (I) as one molecule. Example 1 Synthesis of n-butyl polyacrylate (PBA) polymer initiator 1 kg of butyl acrylate (BA) and 1 kg of toluene
And 1 g of benzoyl peroxide (BPO)
The mixture was heated and reacted at 80 ° C. for 2 hours in a nitrogen stream. This solution was added dropwise to 15 l of methanol to precipitate the product.
The polymer obtained was vacuum dried at 80 ° C. for 12 hours,
A890 g was obtained. The number average molecular weight of this polymer is GP
As a result of measurement by the C (gel permeation chromatography) method, the yield was 100,000 and the yield was 89%.

440 g of this PBA (BA: 3.4 mol)
Dehydrated and purified tetrahydrofuran (THF) 1
0 L, cooled to −75 ° C. while stirring in a stream of dry argon gas, and cooled to a lithium diisopropylamide (LDA) solution (27% by weight, THF / heptane solution).
16 ml (LDA: 34 mmol) were added dropwise. After one hour, 10.3 ml of trimethylsilyl chloride (TMSC) (8
3 mmol) and reacted at 25 ° C. for 3 hours. Then, THF as a solvent was distilled off, and 10 l of dehydrated and dried diethyl ether was added and dissolved. The salt was removed by filtration, and then diethyl ether was distilled off. 440 g of a molecular initiator was obtained (yield 98%). The structure was confirmed by NMR, and the number of initiation sites in the polymer initiator was 8 on average per molecular chain. The glass transition temperature was -55 ° C as measured by DSC (differential scanning calorimetry). [Living polymerization of methyl methacrylate (MMA)] Next, 440 g of this polymer initiator (starting site: 34 mmol)
Was dissolved in _{^{THF2l, TAS + (CH 3)}} 3 SiF 2 -
70 ml of acetonitrile solution (0.18 mmol / ml) was added, and at 0 ° C., 700 ml of methyl methacrylate (MMA) was added.
(660 g, 6.6 mol) was added dropwise and reacted for 2 hours. The reaction solution was dropped into methanol, and the resulting BA / MMA graft copolymer (stem: PBA, branch: PM
MA, PBA / PMMA = 40/60) precipitate 1050
g was obtained (95% yield). Table 1 shows the evaluation results of the yield, total light transmittance, tensile strength and elongation, and weather resistance of the obtained graft copolymer. Example 2 In a living polymerization of MMA in the same manner as in Example 1, the polymer initiator 69 obtained in the same manner as in Example 1 was used.
0 g (starting site: 53 mmol) was dissolved in 3 l of THF.
110 ml of a solution of AS ⁺ (CH ₃ ) ₃ SiF ₂ ^- in acetonitrile (0.18 mmol / ml) was added, and at 0 ° C., MMA
490 ml (460 g, 4.6 mol) were added dropwise and reacted for 2 hours. The reaction solution was dropped into methanol, and the product BA / MMA graft copolymer (stem: PBA,
Branch: PMMA, PBA / PMMA = 60/40) to obtain 1090 g (95% yield). Table 1 shows the yield, total light transmittance, tensile strength, elongation at break, and weather resistance of the obtained graft copolymer. Example 3 [Synthesis of PMMA polymer initiator] 991 g of MMA, 9 g of methyl acrylate (MA), and 2 g of BPO were mixed with toluene 1
The mixture was dissolved in kg and heated at 80 ° C. for 2 hours in a nitrogen stream to cause a reaction. This solution was added dropwise to 15 l of methanol to precipitate the product. The obtained polymer was vacuum-dried at 80 ° C. for 12 hours to obtain 910 g of an MMA / MA copolymer. The number average molecular weight of this polymer measured by GPC was 90,000 (yield 91%).

600 g of this MMA / MA copolymer (M
A: 62 mmol) was dissolved in 10 l of well-dehydrated and purified THF, and stirred in a stream of dry argon gas under -75.
After cooling to 0 ° C., 29 ml of LDA solution (27% by weight, THF / heptane solution) (LDA: 62 mmol) were added dropwise. One hour later, 19 ml (156 mmol) of TMSC was added, and 2 more
The reaction was performed at 5 ° C. for 3 hours. Then, THF as a solution was distilled off, and 10 l of dehydrated and dried diethyl ether was added and dissolved. The salt was removed by filtration, and then diethyl ether was distilled off. 600 g of a molecular initiator was obtained (yield 98%). Structure is N
Confirmed by MR, the number of initiation sites in the polymeric initiator was
The average was 9 per molecular chain. The glass transition temperature was 106 ° C. as measured by DSC. [Living polymerization of BA] Next, this polymer initiator 600
g (starting site: 62 mmol) was well dehydrated and purified 1,2
-Dissolve in 5 l of dichloroethane and add zinc chloride 40 (300
mmol), and the temperature of the reaction system was set to 0 ° C. under stirring. Next, 400 g (3.1 mol) of BA was added dropwise and reacted for 2 hours. The reaction solution was dropped into methanol, and the product MMA / BA graft copolymer (stem: PMM
A, branch: PBA, PMMA / PBA = 60/40) to obtain 940 g of a precipitate (94% yield). Table 1 shows the yield, total light transmittance, tensile elongation and weather resistance of the obtained graft copolymer. Example 4 [Synthesis of polyethyl acrylate (PEA) polymer initiator] 1 kg of ethyl acrylate (EA), 1 kg of toluene and 1 g of BPO were mixed and dissolved, and heated and reacted at 80 ° C. for 2 hours in a nitrogen stream. . This solution was dropped into 15 l of hexane to precipitate the product. The obtained polymer was vacuum-dried at 80 ° C. for 12 hours to obtain 880 g of PEA. The number average molecular weight of this polymer was 80,000 as measured by GPC, and the yield was 88%.

660 g of this PEA (EA: 6.6 mol)
Was dissolved in 10 liters of THF which had been thoroughly dehydrated and purified, and cooled to -75 ° C. while stirring in a stream of dry argon gas.
A solution (27% by weight, THF / heptane solution) 15 ml
(LDA: 33 mmol) was added dropwise. One hour later, TMSC
10.3 ml (83 mmol) was added, and the mixture was further reacted at 25 ° C. for 3 hours. Then, THF as a solvent is distilled off,
10 l of dried diethyl ether was added and dissolved, and the mixture was further filtered to remove salts as a by-product. Then, diethyl ether was distilled off to obtain 660 g of a polymer initiator as a product (yield: 99%). ). The structure was confirmed by NMR, and the number of initiation sites in the polymer initiator was 4 on average per molecular chain. The glass transition temperature is DSC
Was -24 ° C. [Living polymerization of MMA] Next, this polymer initiator 66
0 g (starting site: 33 mmol) was dissolved in 3 l of THF.
^{_{AS + (CH 3) 3 SiF}} 2 - in acetonitrile (0.18mmol / ml) 70ml was added, at 0 ℃, MMA4
66 ml (440 g, 4.4 mol) was added dropwise and reacted for 2 hours. The reaction solution was dropped into methanol, and the product EA / MMA graft copolymer (stem: PEA, branch:
PMMA, PEA / PMMA = 60/40) precipitate 10
50 g was obtained (95% yield). Table 1 shows the evaluation results of the yield, total light transmittance, tensile strength, elongation at break, and weather resistance of the obtained graft copolymer. Example 5 [Synthesis of ethylene-ethyl acrylate copolymer-based polymer initiator] Ethylene-ethyl acrylate copolymer NUC-
6570 (Ethylene / EA = 75, manufactured by Nippon Yunika Co., Ltd.)
/ 25, number average molecular weight Mn = 161000 (GPC))
500 g (EA: 1.1 mol) was dissolved in a well-dehydrated and purified mixed solvent of 9 l of tetralin and 1 l of THF, and cooled to 0 ° C. with stirring in a stream of dry argon to give an LDA solution (27% by weight, THF / heptane solution). ) 21ml (LD
A: 44 mmol) was added dropwise. After one hour, 13 ml of TMSC
(110 mmol) and further reacted at 25 ° C. for 3 hours. Then, the salt as a by-product was removed by filtering the solution, and tetralin and THF as solvents were distilled off.
500 g of a polymer initiator as a product was obtained (yield: 100
%). The number of initiation sites in the polymeric initiator was an average of 10 per molecular chain. The glass transition temperature is DSC
Was -100 ° C or less. [Living polymerization of MMA] Next, this polymer initiator 50
0 g (starting site: 44 mmol) was dissolved in 3 liters of tetralin, 90 ml of a solution of TAS ⁺ (CH ₃ ) ₃ SiF ₂ ^- in acetonitrile (0.18 mmol / ml) was added.
350 ml (330 g, 3.3 mol) was added dropwise and reacted for 2 hours. The reaction solution was dropped into methanol, and the product ethylene-EA / MMA graft copolymer (stem:
Ethylene-EA copolymer, branch: PMMA, ethylene-E
790 g of a precipitate of A copolymer / PMMA = 60/40) was obtained (yield: 95%). Table 1 shows the evaluation results of the yield, total light transmittance, tensile strength, elongation at break, and weather resistance of the obtained graft copolymer. Comparative Example 1 [Synthesis of MMA Macromonomer Initiator Vinylphenylketenemethyltrimethylsilylacetal (VPATSA)] Commercially available vinylbenzyl chloride (meta form 60)
%, 40% para-form) (12.2 g) and 5 g of NaCN
In a mixed solvent of methanol / water = 12.2 g / 5 g,
The reaction was performed at 4 ° C. for 12 hours. The reaction product solution was filtered and distilled off, followed by distillation under reduced pressure to give vinylbenzyl cyanide 8.1.
g was obtained (yield 71%). 6.4 g of this vinylbenzyl cyanide was dissolved in 1.8 g of absolute ethanol, 2.0 g of dry hydrogen chloride was absorbed with stirring at 0 ° C., and the solution was allowed to stand in a refrigerator for 24 hours. The resulting precipitate of imide ester hydrochloride was filtered and dried in vacuo.

After 6.7 g of this imide ester hydrochloride and 3.4 g of water were stirred at room temperature for 15 minutes, the solution was concentrated and distilled under reduced pressure to obtain 4.7 g of methyl vinylphenylacetate (yield: 59%).

In a vessel purged with nitrogen, 8% LDA in THF
26.8 g of solution were charged. The container was cooled on ice, 3.5 g of methyl vinylphenylacetate was added dropwise over 5 minutes, and the mixture was stirred for 30 minutes. To this solution, 5.4 g of TMSC was added dropwise over 5 minutes, and the reaction mixture was returned to room temperature. After stirring at room temperature for 30 minutes, the reaction solution was filtered, and the filtrate was further concentrated. The residue was washed with anhydrous ether, and the filtration was repeated several times. After distilling off the ether, the residue was distilled under reduced pressure to obtain VPKTSA2.
2 g were obtained (yield 45%). [Synthesis of MMA macromonomer by GTP method] 2.2 g of VPKTSA in 100 ml of anhydrous THF under dry nitrogen
(8.97 mmol) and ^{_{TAS + (CH 3) 3 SiF}} 2 - 0.
03 g (0.11 mmol) and 89.7 g (0.
897 mmol) and polymerized at room temperature for 3 hours. A hexane solution containing 5% methanol was added to the reaction solution, and Mn = 110
A precipitate of a macromonomer of polyMMA having a styryl group at one end of Mw / Mn = 1.10 was obtained at a yield of 90%. NMR revealed that the introduction ratio of the styryl group was 100%. [Synthesis of BA / MMA graft copolymer] 60 g of MMA macromonomer, 40 g of BA, and 0.5 g of BPO were dissolved in 300 ml of toluene, and the mixture was sufficiently substituted with nitrogen and reacted at 80 ° C for 3 hours. The reaction solution was dropped into methanol and precipitated, and then dried under vacuum to obtain 84 g of a BA / MMA graft copolymer (BA / MMA = 40/60) (yield: 84).
%). Table 1 shows the yield, total light transmittance, tensile elongation and weather resistance of the obtained graft copolymer. Example 6 [Synthesis of Polymethyl Methyl Acrylate (PMA) Polymer Initiator] 1 kg of methyl acrylate (MA), 1 kg of toluene and 1 g of BPO were mixed and dissolved, and heated and reacted at 80 ° C. for 2 hours in a nitrogen stream. . This solution was dropped into 15 l of hexane to precipitate the product. The obtained polymer was vacuum-dried at 80 ° C. for 12 hours to obtain 900 g of PMA. The number average molecular weight of this polymer was 90,000 as measured by GPC, and the yield was 90%.

8.6 g of this PMA (MA: 0.1 mol)
Was dissolved in 10 l of well-dehydrated and purified THF, and cooled to −75 ° C. while stirring in a stream of dry argon gas.
47 ml of DA solution (27% by weight, THF / heptane solution)
(LDA: 0.1 mol) was added dropwise. One hour later, TMS
C31 ml (0.25 mol) was added, and the mixture was further reacted at 25 ° C. for 3 hours. Then, THF as a solvent was distilled off, 2 liters of dehydrated and dried diethyl ether was added and dissolved, and further filtration was performed to remove a salt as a by-product. 15.5 g of a molecular initiator was obtained (yield 98%). The structure was confirmed by NMR, and the number of initiation sites in the polymer initiator was 1,050 per molecule chain on average. The glass transition temperature was about 10 ° C. as measured by DSC. [Living polymerization of MMA] Next, the polymer initiator 9.
2 g (starting site: 59 mmol) was dissolved in 11 of THF, and T
^{_{AS + (CH 3) 3 SiF}} 2 - in acetonitrile (0.18mmol / ml) 7ml added, at 0 ℃, MMA10
0.6 ml (95 g, 0.95 mol) was added dropwise and reacted for 2 hours. The reaction solution was dropped into methanol, and the resulting MA / MMA graft copolymer (stem: PMA,
Branch: precipitation of PMMA, PMA / PMMA = 5/95) 9
5 g was obtained (95% yield). Table 1 shows the evaluation results of the yield, total light transmittance, tensile strength, elongation at break, and weather resistance of the obtained graft copolymer. Comparative Example 2 The total light transmittance, tensile strength, elongation at break, weather resistance and dynestat impact strength of commercially available PMMA (Acrypet VH, trade name, Mitsubishi Rayon Co., Ltd.) were evaluated, and the results are shown in Table 2. Indicated.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

According to the method for producing a graft copolymer of the present invention, a polymer compound constituting the trunk of the graft copolymer and a (meth) acrylate component constituting the branch are selected from a wide range. Thus, it has become possible to produce a (meth) acrylic acid ester-based graft copolymer in which the chain length of the trunk portion and the chain length of the branch portion are controlled in high yield.

Further, the method for producing a graft copolymer of the present invention is characterized in that, for example, a (meth) acrylate resin excellent in transparency, weather resistance and mechanical properties, or a (meth) acrylate having properties as an elastomer. Extremely excellent production that enables easy production of high-performance and high-performance resins such as acrylate resins, as well as the production of graft copolymers whose desired molecular structure is regulated according to the application. Is the law.

────────────────────────────────────────────────── ─── Continued on the front page (56) References WO 88/6603 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 265/06 C08F 4/00

Claims (3)

(57) [Claims] 1. A polymer compound having at least one unit represented by the following general formula (I) in a molecular chain as an initiator in the substantially absence of water, and in the presence of a Lewis acid,
Alternatively, living polymerization of at least one (meth) acrylate ester is performed in the presence of a compound serving as a source of an anion selected from HF ₂ ⁻ , (CH ₃ ) ₃ SiF ₂ ⁻ and F ^−. A method for producing a graft copolymer. Embedded image (In the formula, R represents hydrogen or an alkyl group having 1 to 6 carbon atoms, and R 'represents an alkyl group having 1 to 12 carbon atoms.) 2. The method for producing a graft copolymer according to claim 1, wherein the polymer compound has two or more units represented by the general formula (I) in a molecular chain. 3. The high molecular compound has a molecular weight of 1,000.
The method for producing a graft copolymer according to claim 1 or 2, wherein