JPH05345841A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the thermoplastic resin composition excellent in flexibility and weather resistance and good in appearance characteristic. CONSTITUTION:This thermoplastic resin composition comprises (A) a polyolefinic resin, (B) the hydrogenated product of a thermoplastic block copolymer composed of a block comprising an aromatic vinyl monomer and a block comprising an isoprene and/or butadiene, (C) an acrylic resin, (D) a hydrocarbon-based softening agent, and (E) the hydrogenated product of a thermoplastic block copolymer composed of a block comprising an aromatic vinyl monomer and a block comprising isoprene and/or butadiene and having the polymer of an acrylic monomer on side chains in amounts of 100 pts.wt., 10-300 pts.wt., 10-300 pts.wt., 0-500 pts.wt., and 0-50 pts.wt., respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition having excellent flexibility and weather resistance and good appearance characteristics.

[0002]

2. Description of the Related Art As a resin excellent in flexibility and appearance characteristics,
Hitherto, polyolefin resins, polystyrene resins, polyvinyl chloride resins, polyurethane resins, polyester resins and the like have been known, and are widely marketed and put into practical use. If the field of use is illustrated, it will be used for interior parts of automobiles, bumpers, housings of home appliances, and the like. Compared with these resins, polystyrene-based thermoplastic elastomers such as styrene-butadiene and hydrogenated products of styrene-isoprene block copolymers have excellent mechanical properties, flexibility, and processability, and are included in the molecular chain. The heat resistance can be improved by using the unsaturated double bond hydrogenated and used, and the use for the above-mentioned uses is spreading. As for this polystyrene-based thermoplastic elastomer, for example, JP-A-59-31541 discloses a composition in which a polyolefin-based resin, a hydrocarbon-based softening agent and the like are mixed. However, these thermoplastic resin compositions, compared to other polystyrene, polyvinyl chloride, the composition mainly resin such as polyester,
Although it is excellent in flexibility, it has the drawback of being inferior in surface gloss and the like of the molded product. Further, although the coloring property is excellent as compared with the polyolefin-based resin composition, the resin itself does not have a polar group, so that it is unsatisfactory for the coating property.

Therefore, a method of blending polyethylene, polypropylene or the like with a polystyrene type thermoplastic elastomer has been carried out for the purpose of improving the surface characteristics, but the low temperature characteristics are insufficient although the appearance is improved. Further, a composition containing a polypropylene-based block copolymer, which is an improvement thereof, has been proposed (JP-A-61-124848, etc.). By this method, the surface and appearance characteristics are improved, but the weather resistance is not satisfactory. Occurs.

In contrast to these thermoplastic resin compositions, acrylic resins are used in various materials by taking advantage of their characteristic surface properties such as transparency, color developability, weather resistance and surface hardness. In particular, it is often used outdoors as a weather-resistant resin having good color development, and is also used as a transparent material such as a fluorescent lamp cover and an automobile rear panel. In addition, since it decomposes into a monomer when heated, it is also being studied as a recyclable material. However, acrylic resins are generally poor in flexibility and low-temperature characteristics, and many studies have been conducted for the purpose of improving these drawbacks.

The present invention is to solve the above-mentioned problems by blending an acrylic resin with a resin composition containing a polyolefin resin composition and a polystyrene saturated thermoplastic elastomer as main components.

[0006]

SUMMARY OF THE INVENTION The object of the present invention, however, is to provide a flexible resin composed of a polyolefin resin, a hydrogenated product of a thermoplastic block copolymer, an acrylic resin and a hydrocarbon softening agent. It is intended to provide a novel thermoplastic resin composition having excellent weather resistance and having excellent mechanical properties and appearance characteristics.

[0007]

According to the present invention, the above-mentioned problems are (A): 100 parts by weight of a polyolefin resin, (B): a block composed of an aromatic vinyl monomer, and isoprene and / or butadiene. A hydrogenated product of a thermoplastic block copolymer composed of a block consisting of
0 parts by weight, (C): 10 to 300 parts by weight of acrylic resin, (D): 0 to 500 parts by weight of a hydrocarbon softening agent, and (E): a polymer of an acrylic monomer in the side chain. A thermoplastic resin composition containing 0 to 50 parts by weight of a hydrogenated product of a thermoplastic block copolymer composed of a block composed of an aromatic vinyl monomer and a block composed of isoprene and / or butadiene. , Has been found to be solved.

The present invention will be described in detail below. (I) Polyolefin-based resin In the present invention, the polyolefin-based resin used as the component (A) is a homopolymer of an olefin monomer typified by polyethylene, polypropylene or the like, or an ethylene-propylene random copolymer, an ethylene-propylene block copolymer, or the like. And a copolymer composed of two or more kinds of monomers. It is not limited to the use of one type of polyolefin resin for the intended use, and in some cases, two or more types of polyolefin resin may be used in combination. (Ii) Hydrogenated Product of Thermoplastic Block Copolymer The hydrogenated product of the thermoplastic block copolymer used as the component (B) is a block (a) made of an aromatic vinyl monomer, isoprene and / or And a block (b) made of butadiene. The aromatic vinyl monomer used here is styrene, α-methylstyrene or the like, and these can be used alone or in combination of two or more kinds. The block (a) composed of an aromatic vinyl monomer has a number average molecular weight of 3,000 to 8,000.
It is preferably in the range of 0. The block (a)
Is 10 to 6 in proportion to the total weight of the block (b).
It is preferably in the range of 0% by weight, and this maintains the thermoplasticity of the hydrogenated product of the thermoplastic block copolymer as the component (B).

The number of segments of the block (a) can be arbitrarily determined, but if it is too large, it is not preferable because the manufacturing process becomes complicated.
Even if the number of segments is as small as ~ 5, sufficient performance can be exhibited and no problem occurs in the physical properties of the product.

The block (b) composed of isoprene and / or butadiene has a number average molecular weight of 20000 to 2000.
It is preferably in the range of 00, whereby the thermoplasticity of the hydrogenated product of the thermoplastic block copolymer which is the component (B) is maintained. When the number average molecular weight of the block (b) exceeds the above range, the hydrogenated product of the thermoplastic block copolymer as the component (B) impairs fluidity, which is not preferable.

In the block (b), isoprene and butadiene can be used alone, or both can be copolymerized in an arbitrary ratio. In this case, both random and block structures can be used depending on the purpose. can do. Further, hydrogenation is carried out to improve the heat resistance and weather resistance of this block, but the properties of the thermoplastic elastomer can be maintained because the temperature of the Garnish transition is hardly changed. In order to satisfy desired heat resistance and weather resistance, the hydrogenation rate is preferably 70% or more.

The hydrogenated product of the thermoplastic block copolymer as the component (B) is not miscible with the respective components of the components (A) and (C) until the above conditions are satisfied. When the plastic resin composition is used, the desired good mechanical strength can be obtained.

The method for synthesizing a hydrogenated product of a thermoplastic block copolymer is obtained by obtaining a polymer by anionic living polymerization which is usually carried out using an organic alkali metal catalyst, and then hydrogenating this. For example, a saturated aliphatic hydrocarbon compound such as hexane, heptane or cyclohexane using an anionic polymerization initiator such as n-butyllithium or s-butyllithium, or an aromatic hydrocarbon compound such as benzene, toluene or xylene is used as a solvent. A living polymer is produced by anionically polymerizing an aromatic vinyl monomer under a temperature condition of 30 to 60 ° C., and then a conjugated diene monomer such as isoprene or butadiene is dropped into the system to produce a block copolymer. Polymerize,
In some cases, an aromatic vinyl monomer is dropped again into the system to produce a block copolymer. By repeating this operation, a living polymer having a desired number of segments can be produced. The living polymer thus obtained may also be subjected to a coupling treatment with a dihalogen compound such as 1,2-dibromoethane, 1,4-dibromobutane or 1,4-dichlorobenzene, or a tin compound such as tin tetrachloride. A block copolymer of segments can be obtained. Alternatively, when a bifunctional anionic polymerization initiator such as 1,4-dilithiobutane or dilithionaphthalene is used as the polymerization initiator, a triblock can be obtained by adding a conjugated diene monomer and then an aromatic vinyl monomer in this order. A copolymer is produced. Further, by repeating this operation, a multi-segment block copolymer can be produced. When carrying out the polymerization, ethers such as dimethyl ether, diethyl ether, tetrahydrofuran and dioxane as cocatalysts, glycol ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether, triethylamine, N, N,
Amine base such as amines such as N ′, N′-tetramethylethylenediamine and N-methylmorpholine is used in an amount of about 0.1 to 1000 with respect to the number of moles of the metal cation of the polymerization catalyst.
When it is used in the double range, the microstructure of the block segment composed of isoprene and / or butydiene is changed to contain a vinyl bond. When this vinyl structural unit is 40% or more, it has a glass transition temperature near room temperature, and vibration damping performance near room temperature can be imparted (JP-A-2-102212). And
When the desired molecular weight is reached, active hydrogen compounds such as alcohols, carboxylic acids and water are added to terminate the polymerization.

Subsequently, the obtained copolymer is hydrogenated to produce a hydrogenated product of a thermoplastic block copolymer. As the hydrogenation catalyst, a homogeneous catalyst or a heterogeneous catalyst can be used. When a homogeneous catalyst is used, an organic transition metal catalyst (for example, nickel acetylacetonate, cobalt acetylacetonate, nickel naphthenate, cobalt naphthenate, etc.) and an alkyl compound of a metal such as aluminum, an alkali metal or an alkaline earth metal is used. The combined Ziegler catalyst is used in an amount of about 0.01 to 0.1 mol% per double bond of the polymer to be hydrogenated. The hydrogenation reaction is carried out at room temperature to 150 ° C. and atmospheric pressure to 50 kg / cm ² of hydrogen pressure, and is completed in about 1 to 50 hours. After completion of the reaction, acidic water is added to the vessel and vigorously stirred to dissolve the hydrogenation catalyst in water. By removing the aqueous phase of the two phases that have been phase-separated and further distilling off the solvent, the hydrogenated product of the desired thermoplastic block copolymer is obtained.

When a heterogeneous catalyst is used, nickel, cobalt, palladium, rhodium, ruthenium, platinum, etc. may be used alone or in combination with silica, diatomaceous earth, alumina,
It is used by supporting it on activated carbon or the like, and its amount is suitably 0.5 to 10% by weight based on the weight of the polymer. This is added to the polymerization reaction liquid. At this time, ethers such as diethyl ether, tetrahydrofuran and dioxane, and alcohols such as ethanol and isopropanol can also be used as a mixed solvent. The hydrogenation reaction is from room temperature to 250 ° C,
It is carried out under a hydrogen pressure of atmospheric pressure to 200 kg / cm ² , and about 1 to
It ends in 50 hours. After the completion of the reaction, the reaction product is taken out from the container, the catalyst is filtered off, and the solvent is distilled off from the obtained filtrate to obtain the desired hydrogenated product of the thermoplastic block copolymer. (iii) Acrylic resin The acrylic resin used as the component (C) is a homopolymer of methyl methacrylate or a small amount of another copolymerizable monomer containing methyl methacrylate as a main component. It is a copolymer. As the copolymerization component, acrylic acid, acrylic acid metal salt, methyl acrylate, ethyl acrylate, n-butyl acrylate, s-butyl acrylate, t-butyl acrylate, acrylic acid ester such as 2-ethylhexyl acrylate, etc. , Methacrylic acid, methacrylic acid metal salt, ethyl methacrylate, n-butyl methacrylate, s-butyl methacrylate, methacrylic acid t
-Butyl, 2-hydroxyethyl methacrylate, glycidyl methacrylate, methacrylic acid esters such as cyclohexyl methacrylate, acetic acid esters such as vinyl acetate, unsaturated nitrile compounds such as acrylonitrile, aromatics such as styrene and α-methylstyrene Group vinyl compounds, maleic anhydride, maleic acid mono- and dialkyl esters, maleimides such as N-phenylmaleimide, and the like, and one or more of them may be used in any combination and in any ratio. it can. The copolymerization ratio with methyl methacrylate is preferably a ratio that does not significantly change the properties of the acrylic resin, and specifically, it can be used at about 0.01 to 30% by weight. (Iv) Hydrocarbon-based Softening Agent The hydrocarbon-based softening agent used as the component (D) is a polyolefin-based softening agent such as a hydrocarbon oil typified by process oil, polybutene oligomer, polyisobutene oligomer, or the like. These softening agents can also be used alone or in combination of two or more kinds. (V) Hydrogenated Product of Thermoplastic Block Copolymer Having Acrylic Monomer Polymer in Side Chain In this component (E), side chain acrylic monomer polymer (E1) is (C ) Component has a high affinity, a block composed of an aromatic vinyl monomer of the main chain and isoprene and /
Alternatively, since the hydrogenated product (E2) of the thermoplastic block copolymer composed of a block made of butadiene has a high affinity for the components (A) and (B), it has an effect as a compatibilizer. is there.

The component (E1) in the component (E) is basically the same polymer as described for the component (C),
It is a polymer of methyl methacrylate alone or a copolymer obtained by copolymerizing methyl methacrylate as a main component with a small amount of another monomer having copolymerizability. As the copolymerization component, one or more kinds of copolymerization monomers similar to those used in the component (C) can be used in any combination and in any ratio, but it should be the component (C). Those having similar compositions are preferable.

The component (E2), which is the main chain, is produced by a method similar to that described for the component (B), and the component (B) synthesized by anion living polymerization using an organic alkali metal catalyst which is usually performed. Is obtained by hydrogenating a polymer similar to. The structure has a block (a) in which the block of the aromatic vinyl monomer of (E) is composed of the aromatic vinyl monomer of the component (B), and a block of further isoprene and / or butadiene in the (E). Is preferably similar to the block (b) consisting of isoprene and / or butadiene as the component (B). Further, by hydrogenating at 70% or more, the heat resistance and weather resistance are excellent, and by having a molecular structure similar to that of the component (B), the compatibilizing effect is excellent. Further, when the number of each block segment of the component (E2) is 2 or 3, it is most effective in terms of compatibilization and manufacturing cost.

The components (E1) and (E) in the component (E) are
2) The ratio of the components can be arbitrarily determined, but in order to clarify the effect as a compatibilizer, the closer the component ratio is,
Specifically, (E1) / (E2) (weight ratio) is 25/75
The range of ~ 75/25 is preferred.

For the component (E), various synthetic methods have been proposed so far, and any method can be selected from them, but basically, the component consisting of (E1),
It is obtained by chemically bonding the component (E2).
For example, in the presence of (1) :( E2) component, the monomer constituting (E1) component is converted to (C1) by radical reaction such as hydrogen abstraction using a catalyst such as peroxide.
2) A method in which the side chain of the component is graft-polymerized, (2): (E
1) Introducing a reactive double bond at the terminal of the molecular chain of the component polymer to cause an addition reaction to the residual double bond in the component (E2),
A method in which the ends of the molecular chains of the component (E1) polymer are bonded by radical hydrogen abstraction reaction, (3): (E
2) Component having functional group such as dibasic acid anhydride introduced to modify carboxylic acid, and (E1) component having a hydroxyl group or an active hydrogen group such as primary or secondary amino acid at the end of the molecular chain. A method of reacting the introduced polymer is known.

Although any of these methods can satisfy the requirements for the component (E) to be produced,
In particular, it is important to control the molecular structure of the graft polymer more finely in order to enhance the compatibilizing effect. (E1), (E2) The reaction rate, the content of the branched side chain component, etc. can be determined by grasping the molecular weight, molecular weight distribution, functional group content, etc. of each raw material component,
It is possible to design the component (E) more appropriately for the combination of (A), (B), and (C). From the above viewpoint, the manufacturing method described in (3) above is most suitable.

The manufacturing method (3) will be described below. (E
The component 2) is produced by a method similar to the method described in detail for the production method of the component (B), and is a polymer similar to the component (B) synthesized by anion living polymerization using an organic alkali metal catalyst which is usually performed. Is obtained by hydrogenating.
The structure has a block (a) in which the block of the aromatic vinyl monomer of (E) is composed of the aromatic vinyl monomer of the component (B), and a block of further isoprene and / or butadiene in the (E). Preferably has the same or similar molecular weight as the block (b) composed of the isoprene and / or butadiene as the component (B). Further, by hydrogenating 70% or more, heat resistance and weather resistance are excellent, and (B)
The compatibilizing effect is excellent because it has a molecular structure similar to that of the component. Further, when each block segment of the component (E2) is composed of two or three components, the effect is exhibited in terms of compatibilization and manufacturing cost. The component (E2) thus obtained and a dibasic unsaturated acid anhydride such as maleic anhydride, itaconic anhydride, or citraconic anhydride are mixed with a hydrocarbon such as toluene, xylene, or cyclohexane, if necessary. In a system solvent, 0.01 to 1% by weight of a peroxide catalyst such as benzoyl peroxide, dicumyl peroxide and di (t-butyl) peroxide is added to the component (E2), if necessary. Then, the carboxylic acid-modified product of the component (E2) is obtained by reacting at room temperature to 200 ° C. for 1 to 100 hours with stirring.

On the other hand, as a method of introducing a hydroxyl group or an active hydrogen group such as a primary or secondary amino group into the terminal of the molecular chain of the component (E1), the following method can be exemplified. The component (E1) used here is
A polymer similar to that described for component (C),
It is a homopolymer of methyl methacrylate or a copolymer containing methyl methacrylate as a main component and a small amount of a monomer having the same copolymerizability as used in the component (C). The monomer copolymerized with methyl methacrylate may be used in any combination of one or more kinds and in any ratio, but it is preferable that the composition is as close as possible to the component (C). Saturated carbonyl compounds such as ethyl acetate, butyl acetate, acetone, and methyl ethyl ketone, and hydrocarbon compounds such as toluene and xylene are used as a solvent as required, and methyl methacrylate alone or methyl methacrylate and copolymerizability therewith A monomer is a thiol compound (a hydroxyl group-containing thiol compound such as 2-hydroxyethanethiol if a hydroxyl group is introduced at the terminal, and an amino group-containing thiol compound such as 2-aminoethanethiol if an amino group is introduced. Etc.) in the presence of an ordinary radical polymerization initiator, for example, an organic azo compound such as 2,2′-azobisisobutyronitrile or 2,2′-azobis (2-methylbutyronitrile) at room temperature. ~ 100 ° C
Then, the active hydrogen group is introduced into the terminal of the molecular chain of the component (E1) by carrying out the polymerization for 3 to 30 hours. There is no strict limitation on the molecular weight of the acrylic resin having a hydroxyl group or a primary or secondary amino group at the terminal of the molecular chain thus obtained, but if this is unnecessarily large, the carboxylic acid modified product of (E2) is obtained. The reactivity with (A) or the component (B) becomes too high, and the melt viscosity of the component (E) obtained by the reaction with the carboxylic acid modified product of the component (E2) becomes too large. Since it becomes difficult to carry out, it is preferable that the number average molecular weight is in the range of 10,000 to 80,000. The component (E) is obtained by the reaction between the terminal active hydrogen group of the component (E1) and the carboxylic acid anhydride residue of the component (E2). This reaction is carried out, for example, by using a common solvent for both components such as toluene and xylene. It is dissolved in an aromatic hydrocarbon compound or the like and stirred at room temperature to 250 ° C. for 0.5 to 100 hours for reaction, or in a melt kneader such as an extruder or a kneader at 170 to 300 ° C. and a residence time of 0. 2-30
This can be done by reacting by melt-kneading of minutes.
The reaction mixture of the component (E1) and the component (E2) thus obtained contains 30 to 100% by weight of the component (E),
Preferably, if only 50 to 100% by weight is contained,
It can be used as it is.

The content of the component (E) may be any amount as long as it can exert a sufficient function as a compatibilizer, but the amount is high because the production cost of the component (E) is higher than the other components. It is better not to increase too much, and it is used in the range of 0 to 50 parts by weight with respect to 100 parts by weight of the component (A).

The thermoplastic resin composition of the present invention may optionally contain various additives such as fillers and pigments for the purpose of increasing the amount, coloring and reinforcing. For example, alumina, talc, carbon black, mica, zeolite, glass fiber, carbon fiber, ferrite, calcium carbonate, aluminum hydroxide and other general fillers, dyes, pigments, flame retardants, ultraviolet absorbers, etc. , Other organic or inorganic additives used as functional additives. Further, the addition amount thereof is in the range of the amount generally used, for example, 0.00 parts with respect to 100 parts by weight of the total resin composition.
1 to 50 parts by weight, or optionally more, can be used.

The method of mixing the components constituting the composition can be carried out by a conventional method, and is not particularly limited. For example, a conventional extruder, melt kneader such as a kneader, or the like can be used to perform mixing in a molten state. At that time, (A), (B), (C), (D),
The respective components of (E) may be melt-kneaded at the same time, or the remaining components may be melt-kneaded with a product obtained by previously melt-kneading two or more members. The resin temperature needs to be kneaded at a temperature not lower than a temperature at which each raw material resin melts and flows, and moreover, a temperature in a range that does not cause deterioration. Specifically, it is in a range of 150 to 300 ° C.
It is carried out at 80 to 280 ° C.

[0026]

EXAMPLES Next, the present invention will be specifically described with reference to examples. In addition, the part in each Example represents a weight part. Moreover, each physical property was calculated | required by the method shown below. (1) Acid value: Titrated directly with 0.1N-potassium hydroxide ethanol solution. (2) Amino value: Titrated directly with 0.01 N-hydrochloric acid methanol solution. (3) Tensile physical property test: Measured using a No. 2 test piece in accordance with JISK-7113. (4) Hardness: ASTMD-2240 or JISK-
Measure according to 6301. (5) Appearance characteristics: The surface of a 11 cm × 11 cm flat plate due to injection molding is visually evaluated for surface roughness, cloudiness and the like. (6) Weather resistance test: Exposing for 100 hours with a weathering tester, visual observation of appearance, and evaluation of retention rate of tensile breaking strength.

In this example, commercially available products described below were used as the polyolefin resin, acrylic resin, and hydrocarbon softening agent. Further, a hydrogenated product of a thermoplastic block copolymer composed of a block composed of an aromatic vinyl monomer and a block composed of isoprene and / or butadiene was produced as described below. Polyolefin resin: Mitsubishi Yuka Nobren MA-3
(Polypropylene homopolymer) Acrylic resin: Kuraray Parapet G-1000 (methacrylic resin) Hydrocarbon softening agent: Idemitsu Kosan Diana Process PW-
Production of hydrogenated product (1) of 90 (paraffin-based oil) thermoplastic block copolymer: 500 parts of cyclohexane and 11 parts of s-butyllithium were charged in a pressure resistant reaction vessel equipped with a stirrer and a dropping funnel, and 5
The temperature was raised to 0 ° C., 60 parts of styrene was continuously charged from a dropping funnel, 280 parts of isoprene was continuously charged, and then 60 parts of styrene was continuously charged to carry out polymerization for 8 hours. Thereafter, the reaction system was replaced with hydrogen, 25 parts of a diatomaceous earth-supported nickel catalyst was added, and the mixture was reacted at 150 ° C. for 10 hours under a hydrogen pressure of 15 kg / cm ² . The reaction product was diluted with cyclohexane, the catalyst was filtered off, and the filtrate was concentrated and dried under reduced pressure to obtain a hydrogenated product (1) of a thermoplastic block copolymer. From the NMR analysis, it was confirmed that the styrene-isoprene-styrene triblock copolymer had a styrene content of 30.3%. Also G
From the analysis of PC, the number average molecular weight of the styrene block was 8,300 and the number average molecular weight of the isoprene block was 3
The total number average molecular weight was 8,500 and the hydrogenation rate by iodine value was 95.6%. Production of hydrogenated product (2) of thermoplastic block copolymer: 500 parts of cyclohexane and s-butyllithium part were charged in a pressure-resistant reaction vessel equipped with a stirrer and a dropping funnel and heated to 50 ° C.
Then, 12.5 parts of styrene was continuously charged from the dropping funnel, 100 parts of isoprene was continuously charged, and then 12.5 parts of styrene was continuously charged.
Polymerization was performed for 0 hours. After that, the reaction system was replaced with hydrogen, and 10 parts of a diatomaceous earth-supported nickel catalyst was added to obtain 15 kg / c.
The mixture was reacted at 150 ° C. for 10 hours under a hydrogen pressure of m ² . The reaction product was diluted with cyclohexane, the catalyst was filtered off, and the filtrate was concentrated and dried under reduced pressure to obtain a hydrogenated product (3) of a thermoplastic block copolymer. It was confirmed by NMR analysis that the styrene-isoprene-styrene triblock copolymer had a styrene content of 20.4%. From the GPC analysis, the number average molecular weight of the styrene block was 20,200, the number average molecular weight of the isoprene block was 155,700, and the total number average molecular weight was 196.
The hydrogenation rate based on the iodine value of 100 was 97.8%.

Next, the hydrogenated product of a thermoplastic block copolymer (hereinafter referred to as a graft copolymer) having a polymer of an acrylic monomer in the side chain used in the present invention is as follows. Manufactured. Acrylic polymer having amino group at the end of molecular chain (1)
Preparation: 300 parts of ethyl acetate was charged into a pressure resistant reaction vessel equipped with a stirrer and a dropping funnel, and then 6.2 parts of 2-aminoethanethiol, 200 parts of methyl methacrylate, 9.9 parts of azobisisobutyronitrile. Were sequentially charged and the temperature was raised to 70 ° C. to carry out polymerization for 10 hours. The obtained polymerization liquid was dropped into n-hexane, the precipitate was filtered off and dried under reduced pressure to obtain polymethyl methacrylate having an amino group at the terminal of the molecule. The molecular weight by GPC was 38,400, and the amino group content by the amino value was 1.21 per molecule. Production of carboxylic acid-modified thermoplastic block copolymer hydrogenated product (1): 30 parts of xylene in a pressure-resistant reaction vessel equipped with a stirrer, thermoplastic block copolymer hydrogenated product (1)
And 300 parts of maleic anhydride were charged and reacted at 230 ° C. for 20 hours. The obtained reaction product was heated at 120 ° C. for 24 hours.
The solvent and unreacted maleic anhydride were removed by vacuum drying for an hour to obtain a hydrogenated product of a carboxylic acid-modified thermoplastic block copolymer. The amount of added maleic anhydride based on the acid value was 2.17 parts. Production of graft copolymer (1): 100 parts of an acrylic polymer having an amino group at the terminal of the molecular chain and 100 parts of a hydrogenated product of a carboxylic acid-modified thermoplastic block copolymer (1) are uniformly mixed with a mixer. However, under nitrogen atmosphere, 230 ℃, 30
The reaction was carried out by feeding into a twin-screw extruder at 0 rpm. The reaction rate by solvent fractionation was 85.5%. Examples 1 to 6 and Comparative Examples 1 to 5 Compositions of polyolefin resins, acrylic resins, hydrogenated products of thermoplastic block copolymers, hydrocarbon softening agents, and graft copolymers shown in Table 3 in a mixer. Under a nitrogen atmosphere, the mixture was fed into a twin-screw extruder at 200 ° C. and 200 rpm and melt-mixed. Table 1 shows the physical properties measured by molding the obtained mixture into various test pieces by an injection molding machine.

[0029]

[Table 1]

[0030]

As is apparent from the results of the examples, according to the present invention, a polyolefin resin, an acrylic resin, a hydrogenated product of a thermoplastic block copolymer, a hydrocarbon softening agent, and a graft copolymer are used. By blending the coalescence, a thermoplastic resin composition having excellent flexibility and weather resistance and good appearance characteristics is provided.

Claims (1)

[Claims] 1. A thermoplastic block copolymer comprising (A): 100 parts by weight of a polyolefin-based resin, (B): a block composed of an aromatic vinyl monomer, and a block composed of isoprene and / or butadiene. Hydrogenated products of 10-30
0 parts by weight, (C): 10 to 300 parts by weight of acrylic resin, (D): 0 to 500 parts by weight of a hydrocarbon softening agent, and (E): a polymer of an acrylic monomer in the side chain. A thermoplastic resin composition containing 0 to 50 parts by weight of a hydrogenated product of a thermoplastic block copolymer composed of a block composed of an aromatic vinyl monomer and a block composed of isoprene and / or butadiene. .