JPH083250A - Method for producing modified block copolymer - Google Patents

Abstract

PURPOSE:To obtain a modified block copolymer improved in adhesion and coating properties and highly useful as an impact modifier for polymers by subjecting a copolymer of an aromatic vinyl compound and a conjugated diene block (or the hydrogenated product thereof) to melt modification by using a specific compound. CONSTITUTION:A modified block copolymer is produced by melt kneading 100 pts.wt. copolymer of an aromatic vinyl compound and a conjugated diene block copolymer and/or the hydrogenated product thereof with 0.01 to 50 pts.wt. hydroxylated alpha,beta-unsaturated carboxylic acid ester in the presence of a free radical initiator. According to this method, it is possible to obtain a modified block copolymer having a larger amount of remaining hydroxyl groups and improved compatibility with other polymers, adhesion and coating properties, and being highly useful as an impact modifier for polymers.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a modified aromatic vinyl compound-conjugated diene block copolymer and / or a hydrogenated product thereof which is excellent in adhesiveness, paintability and performance as a polymer impact modifier. It relates to a manufacturing method.

[0002]

BACKGROUND OF THE INVENTION Aromatic vinyl compound-conjugated diene block copolymers and / or hydrogenated products thereof are useful as coating agents, sealants, adhesives or impact modifiers for polymers. However, with the progress of technological innovation,
When high quality requirements for various products are increasing, the seal strength is as a sealant, the adhesive strength is as an adhesive, and the impact resistance improver for polymers is
Further improvement in affinity with the polymer has been desired. For this reason, JP-A-61-765
Japanese Unexamined Patent Publication No. 18 discloses a method in which maleic anhydride is graft-added to an aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product to improve. Although the introduction of maleic anhydride has a tentative effect, it may be insufficient in a field requiring high properties.

On the other hand, a method of introducing a functional group into a polymer by a melting reaction is generally performed in olefin resins and the like. The melt reaction method is advantageous in that the reaction is easy, fast, and economical. However, as proposed by the present inventors in Japanese Patent Application No. 5-77837 and the like, not only the deterioration of the polymer is feared by the reaction at high temperature but also a part of the functional group may be lost. is there.

[0004]

DISCLOSURE OF THE INVENTION According to the present invention, an aromatic vinyl compound-conjugated diene block copolymer and / or a hydrogenated product thereof is melt-modified to have a hydroxyl group residual ratio (measurement method described later) of 70% or more. Another object of the present invention is to provide a method for producing a modified block copolymer having excellent adhesiveness, paintability, and performance as a polymer impact resistance improver.

[0005]

According to the present invention, 100 parts by weight of an aromatic vinyl compound-conjugated diene block copolymer and / or a hydrogenated product thereof are used in the presence of a radical polymerization initiator to obtain a hydroxyl group-containing α, β. -Unsaturated carboxylic acid ester 0.01 to 20 parts by weight and aromatic vinyl compound 0.01 to
A method for producing a modified aromatic vinyl compound-conjugated diene block copolymer and / or a hydrogenated product thereof, which comprises melt-kneading together with 50 parts by weight. The present invention will be described in detail below.

The aromatic vinyl compound and the conjugated diene block copolymer and / or the hydrogenated product thereof used in the present invention specifically include at least one polymer block mainly containing an aromatic vinyl compound and at least Hydrogenating a block copolymer consisting of one conjugated diene-based polymer block and / or the block copolymer,
It is a hydrogenated block copolymer obtained by hydrogenating at least 80% of an aliphatic double bond based on a conjugated diene in the block copolymer.

Examples of the aromatic vinyl compound include styrene, α-methylstyrene, α-methoxystyrene,
Methylstyrene, dimethylstyrene, 2,4,6-trimethylstyrene, chlorostyrene, dichlorostyrene,
Examples thereof include bromostyrene, nitrostyrene, chloromethylstyrene, cyanostyrene, t-butylstyrene, vinylnaphthalene and the like, and among them, styrene, α-methylstyrene and methylstyrene are preferable. These are single or 2
They can be used in combination of two or more kinds.

As the conjugated diene, for example, one or more selected from butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, etc., among which butadiene, isoprene or Combinations of these are preferred. The polymer block mainly composed of the conjugated diene can have a microstructure in the block arbitrarily selected. For example, in the polybutadiene block, the 1,2-vinyl bond structure is 5 to 65%,
It is preferably 10 to 50%. The molecular structure of the block copolymer may be linear, branched, radial, or any combination thereof.

As a method for producing these block copolymers, for example, an aromatic vinyl compound-conjugated diene block copolymer is used in an inert solvent using a lithium catalyst by the method described in Japanese Patent Publication No. 40-23798. Coalescence can be synthesized. Further, the hydrogenated block copolymer,
It is obtained by hydrogenating the above aromatic vinyl compound-conjugated diene block copolymer. As a method for producing this hydrogenated block copolymer, for example, Japanese Patent Publication Nos. 42-8704 and 43-6636. It can also be obtained by the method described in each publication. In particular, a hydrogenated block copolymer synthesized using a titanium-based hydrogenation catalyst that exhibits excellent heat resistance and heat deterioration resistance of the obtained hydrogenated block copolymer is most preferable. 59-
It can be obtained by hydrogenating the block copolymer having the above-mentioned structure in the presence of a titanium-based hydrogenation catalyst in an inert solvent by the method described in each of JP-A-133203 and JP-A-60-79005. . At that time, at least 80% of the aliphatic double bond based on the conjugated diene of the aromatic vinyl compound-conjugated diene block copolymer is hydrogenated,
It is necessary to morphologically approximate the polymer block mainly containing the conjugated diene to the olefin polymer.

The amount of non-hydrogenated aliphatic double bonds contained in this hydrogenated block copolymer can be easily determined by a Fourier transform infrared spectrophotometer, nuclear magnetic resonance apparatus or the like. Examples of the α, β-unsaturated carboxylic acid ester having a hydroxyl group used in the present invention include the following compounds. Here, the name (meth) acrylate means acrylate and methacrylate. That is,
2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2,3-dihydroxypropyl (meth) acrylate, 2-hydroxymethyl-3-hydroxypropyl (meth) acrylate, 2,2-bishydroxymethyl Examples thereof include (meth) acrylic acid ester of 3-hydroxypropyl (meth) acrylate, oligoethylene glycol or oligopropylene glycol having 4 to 40 carbon atoms.

Further, bis (2-hydroxyethyl) malate, bis (2-hydroxypropyl) malate, bis (2,3-dihydroxypropyl) malate, bis (2
-Hydroxymethyl-3-hydroxypropyl) malate, bis (2,2-bishydroxymethyl-3-hydroxypropyl) malate, etc. and their isomers, fumarate, oligoethylene glycol or oligopropylene glycol having 4 to 40 carbon atoms And maleic acid or fumaric acid ester. Note that maleic acid or fumaric acid ester can be exemplified as a similar compound when both carboxylic acids are not esters of hydroxyalkyl groups as described above and only one is present.

The above α, β-unsaturated carboxylic acid ester having a hydroxyl group can be used alone or in combination of two or more kinds. Among them, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, oligoethylene glycol having 4 to 40 carbon atoms, or (meth) acrylic acid ester of propylene glycol is preferable.

The amount of the α, β-unsaturated carboxylic acid ester having a hydroxyl group added is 0.01 to 20 parts by weight per 100 parts by weight of the aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product. Part, preferably 0.05
The range is from 10 to 10 parts by weight. The amount of the aromatic vinyl compound used in combination with these compounds is 0.01 to 50 parts by weight, preferably 100 parts by weight of the aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product. Is in the range of 0.05 to 20 parts by weight.

The weight ratio of the α, β-unsaturated carboxylic acid ester having a hydroxyl group and the aromatic vinyl compound may be in the range of 1:99 to 99: 1, but is preferably. It is in the range of 10:90 to 90:10, and more preferably in the range of 20:80 to 50: 150. If the aromatic vinyl compound is not added or the ratio is too low, the aromatic vinyl compound-conjugated diene block copolymer and / or the hydrogenated product of the α, β-unsaturated carboxylic acid ester graft-polymerized The residual ratio of hydroxyl groups decreases, and it is not possible to introduce a sufficient amount of hydroxyl groups for reforming the aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product.

[0015]

The function of lowering the residual ratio of hydroxyl groups will be described below, but this is for clarifying the idea of the present invention, and the present invention is not limited thereto. A styrene-isoprene block copolymer hydrogenated product (SEP) having a hydroxyl group-containing methacrylic acid ester
Taking the modified block copolymer graft-polymerized to S) as an example, the mechanism of disappearing the hydroxyl group is as follows. 1) Hydrolysis of ester group (chain)

[0016]

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2) Interaction between two adjacent molecules

[0018]

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(In the formula, R represents an alkylene group) That is, since the hydroxyl group-containing methacrylic acid ester-based monomers are adjacent to each other, an interaction occurs and the ester moiety to which the hydroxyl group is bonded disappears. By interposing a copolymerizable aromatic vinyl monomer, the adjacent vinyl monomer is prevented, and the hydroxyl group residual ratio (measurement method described later) becomes 7
It is kept at 0% or more.

For graft-polymerizing the above-mentioned α, β-unsaturated carboxylic acid ester having a hydroxyl group and a modifier of an aromatic vinyl compound onto an aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product. Required radical polymerization initiators include t-butyl hydroperoxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, t-butylperoxybenzoate, benzoyl peroxide, dicumyl peroxide. Organic and inorganic peroxides such as oxides, 1,3-bis (t-butylperoxyisopropyl) benzene, dibutylperoxide, methylethylketone peroxide, potassium peroxide, hydrogen peroxide; 2,2'-azobisisobutyi. Ronitrile, 2,2'-azobis (isobutyramide) dihalide, 2,2'-azobis [2-methyl-
N- (2-hydroxyethyl) propionamide], azo compounds such as azodi-t-butane; carbon radical generators such as dicumyl, and the like can be used. These radical polymerization initiators can be appropriately selected in relation to the modifier and reaction conditions, and it is also possible to use two or more kinds in combination. The radical polymerization initiator can also be used by dissolving it in an organic solvent or the like.

The amount of the radical polymerization initiator used is preferably 0.01 to 3 with respect to 100 parts by weight of the aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product.
It is 0 part by weight, more preferably 0.05 to 10 parts by weight. The device used for melt kneading is an extruder or a stirrer,
Specifically, a Labo Plastomill, a single-screw or twin-screw kneader; a horizontal twin-screw mixer such as a horizontal twin-screw multi-disk device or a horizontal twin-screw surface renewal machine; or a vertical double-helical ribbon stirrer. Examples include a mold stirrer. The melt-kneading temperature can be any temperature as long as it is a temperature at which the aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product is in a molten state, but the deterioration of the block copolymer can be prevented. Therefore, the temperature is preferably 300 ° C. or lower. The melt-kneading time is preferably 0.1 to 10 minutes, more preferably 0.5 to 5 minutes. Further, in order to prevent deterioration and remove ungrafted matter, it is preferable to melt-knead under a reduced pressure condition, and the pressure is preferably 200 mmHg or less, more preferably 100 mmHg or less, and particularly preferably 50 mmHg or less.

The modifier and the radical polymerization initiator may be added by dry-blending with the aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product and kneading them together, or by modifying the modifier or radical polymerization. There is a method of dry blending one of the agents with the block copolymer and adding the other during kneading, a method of adding a modifier and a radical polymerization initiator to the block copolymer in a molten state, and the like. Further, for the purpose of improving the reaction efficiency, it is possible to add a small amount of an organic solvent such as xylene.

A small amount of general-purpose engineering plastic or the like is added as an additional component to the modified aromatic vinyl compound-conjugated diene block copolymer produced by the present invention and / or its hydrogenated product to improve heat resistance and the like. Is also possible. Examples of general-purpose engineering plastics include polyester, polycarbonate, polyphenylene ether, polyamide, and mixtures thereof. These additional components may be added by first mixing the aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product and modifying the mixture by the above-mentioned production method, or the modified block copolymer obtained by the above-mentioned production method. There are various methods such as a method of mixing with a polymer.

Since the modified aromatic vinyl compound-conjugated diene block copolymer and / or hydrogenated product thereof obtained in the present invention contains a large amount of hydroxyl groups, the adhesiveness, paintability, etc. are improved, and polyester, polycarbonate Since it has an excellent affinity with other polymers, it can be used as a coating agent, a sealant agent, and a polymer impact resistance improver.

[0025]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

Example 1 Styrene-isoprene block copolymer hydrogenated product (Kuraray Co., Ltd., trade name: Septon 2002, hereinafter "S2002"
40 g of powder, 2-hydroxyethyl methacrylate (hereinafter referred to as “HEMA”) 2 g, styrene 2 g
After dry blending 0.06 g of 1,3-bis (t-butylperoxyisopropyl) benzene (hereinafter referred to as “BPIB”), a Labo Plastomill kneader (manufactured by Toyo Seiki Seisakusho Co., Ltd.) was used and the reaction temperature was 180 ° C. , Rotation speed 1
After kneading at 80 rpm for 2 minutes, it was pulverized to obtain a granular resin. 0.3 g of the obtained modified block copolymer was dissolved in 50 ml of chloroform at room temperature to give 300 ml of methanol.
It was poured into ml and precipitated. The precipitate was filtered off and dried under reduced pressure (normal temperature) to obtain a purified resin. The HEMA content of this purified product was determined by the following method.

Quantification of HEMA Infrared spectroscopy (IR method): A sample resin was press-molded into a film, and the IR spectrum was measured. Quantitation is 17
A calibration curve prepared from the characteristic absorption of carbonyl at 24 cm ^-1 was used. Proton nuclear magnetic resonance spectroscopy (NMR method): Sample resin 3
0 to 50 mg was dissolved in 1 ml of o-dichlorobenzene at 130 ° C., a small amount of deuterated benzene was added to prepare a sample, and ¹ H-NMR spectrum was measured. For the quantification, absorption of methylene bonded to a hydroxyl group (chemical shift: 3.9 ppm) and methylene bonded to an ester group (chemical shift: 4.2 ppm) was used. The value obtained by the IR method is the C = 0 amount in the system, that is, H
The amount of grafted EMA is represented, and the value obtained by the NMR method represents the amount of HEMA retaining a hydroxyl group. Therefore, the hydroxyl group residual rate can be defined by the following equation.

[0028]

[Equation 1]

The results are shown in Table 1.

[0030]

[Table 1]

Example 2 Example 1 was repeated except that 2 g of styrene was changed to 4 g. The results are shown in Table 1.

Example 3 In Example 1, 2 g of HEMA was added to 4 g, and styrene 2 was added.
It carried out like Example 1 except having changed g into 4 g. The results are shown in Table 1.

Example 4 The procedure of Example 1 was repeated, except that 0.06 g of BPIB was changed to 0.2 g. The results are shown in Table 1.

Example 5 Styrene-butadiene block copolymer hydrogenated product (manufactured by Shell Chemical Co., trade name: Kraton G1652, hereinafter "G1"
2kg, HEMA 100g, styrene 1
After drive-landing 00g and 10g of BPIB, twin screw extruder (manufactured by Japan Steel Works, trade name: TEX-30 type)
Was used to obtain a modified resin by kneading under reduced pressure at a cylinder temperature of 160 ° C., a screw rotation speed of 300 rpm, a discharge rate of 2 kg / h, and a vent pressure of 50 mmHg. The purification method and the like were the same as in Example 1. The results are shown in Table 1.

Example 6 Example 5 was repeated except that HEMA 100 g was changed to 200 g and styrene 100 g was changed to 200 g. The results are shown in Table 1.

Comparative Example 1 Example 1 was repeated except that S2002 was replaced with G1652 and styrene was not added. The results are shown in Table 1.

COMPARATIVE EXAMPLE 2 In Example 1, except that styrene was not added.
It carried out like Example 1. The results are shown in Table 1.

Application Examples 1 to 3 and Comparative Application Examples 1 to 3 The modified block copolymers obtained in Examples 3, 4 and 5 and Comparative Examples 1 and 2 and polybutylene terephthalate (P
BT) (Made by Mitsubishi Kasei, trade name: Novador 5010)
According to the composition shown in Table 2, each component was used with a Labo Plastomill kneader (manufactured by Toyo Seiki Seisakusho Ltd.) at a reaction temperature of 250.
The mixture was kneaded at a temperature of 180 rpm for 5 minutes and then pulverized to obtain a granular resin composition.

The characteristics of the obtained resin composition were measured by an injection molding machine (CSIS18 manufactured by Custom Scientific).
A test piece injection-molded at a temperature of 260 ° C. using 3MMX Minimax) was measured and evaluated by the following method. The measurement results are shown in Table 2. During the kneading and molding, the saturated polyester and the composition were kept at 120 ° C. for 5 hours until just before that.
Dried for hours.

(1) Impact strength: A test piece having a length of 31.5 mm, a width of 6.2 mm and a thickness of 3.2 mm was injection-molded, and an Izod impact tester (made by Custom Scientific, Minimax CS) was used. -138TI type), 23
The notched Izod impact strength at 0 ° C was measured.

(2) Tensile Strength A tensile test piece having a parallel part length of 7.0 mm and a parallel part diameter of 1.5 mm was injection molded, and a tensile tester (CS-183TE manufactured by Custom Scientific) was used. 23 ° C,
A tensile test was conducted under the conditions of a tensile speed of 1 cm / min, and the tensile yield strength and tensile elongation at break were measured.

(3) Bending elastic modulus A test piece having a length of 47 mm, a width of 5 mm and a thickness of 2 mm was injection-molded,
Using a solid viscoelasticity measuring device (RSAII manufactured by Rheometrics Far East Co., Ltd.), the temperature dependence of the storage elastic modulus (E ′) was measured under the condition of a frequency of 1 Hertz, and the bending elastic modulus at 30 ° C. was obtained.

[0043]

[Table 2]

[0044]

As is clear from the effects of the above examples and application examples, the aromatic vinyl compound-conjugated diene block copolymer and / or its hydrogenated product produced by the present invention has α, β having hydroxyl groups. -A modified block which has a large amount of graft addition of unsaturated carboxylic acid ester and does not lose a hydroxyl group, and thus retains a sufficient amount of hydroxyl group and is excellent as an adhesiveness, paintability and impact modifier of polymer. It is a copolymer and can be an industrially useful material.

Continuation of front page (72) Inventor Mitsutoshi Aritomi 1 Toho-cho, Yokkaichi-shi, Mie Prefecture Yokkaichi Research Institute, Mitsubishi Petrochemical Co., Ltd.

Claims (1)

[Claims] 1. 100 parts by weight of an aromatic vinyl compound-conjugated diene block copolymer and / or a hydrogenated product thereof,
Α, β- having a hydroxyl group in the presence of a radical polymerization initiator
Modified aromatic vinyl compound-conjugated diene block copolymer and / or hydrogen thereof, which is melt-kneaded together with 0.01 to 20 parts by weight of unsaturated carboxylic acid ester and 0.01 to 50 parts by weight of aromatic vinyl compound. Manufacturing method of additives.