JPH09302044A - High-impact styrene resin composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-impact styrene resin composition having an excellent balance between gloss and impact strength. SOLUTION: This composition is obtained by solution-polymerizing at least one conjugated diene monomer in the presence of an organolithium-based catalyst having a molar ratio of a polyvinylaromatic compound to an organolithium compound in the range of 0.1-2.0 (in terms of a ratio of the polyvinylaromatic compound to the lithium atoms) and contains 2-25wt.% conjugated diene polymer having a weight-average molecular weight of 80,000-650,000 (in terms of polystyrene as measured by gel permeation chromatography).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impact-resistant styrene resin composition having a good balance of gloss and impact strength and a method for producing the same.

[0002]

2. Description of the Related Art Polystyrene has been used for various purposes because it has excellent rigidity, transparency, luster and the like and has good moldability. However, this polystyrene has a major drawback of being inferior in impact resistance, and various unvulcanized rubbers are used as a toughening agent in order to improve this drawback. Among them, an impact-resistant styrene-based resin composition in which a styrene-based monomer is radically polymerized in the presence of unvulcanized rubber and a rubber-like polymer is graft-polymerized is industrially widely produced. The unvulcanized rubber used for this purpose includes polybutadiene rubber and styrene-butadiene copolymer rubber, and in particular, polybutadiene rubber is widely used for imparting excellent impact resistance.

In recent years, applications of impact-resistant styrene resins have been
With the spread of housing and other parts of home electric appliances, axle parts, office equipment parts, daily necessities and toys, more excellent various characteristics are required,
There is a strong demand for an impact-resistant styrene-based resin having an excellent balance between appearance characteristics and impact resistance. Generally, the impact resistance can be improved by increasing the content of the rubber-like polymer, but the styrenic resin having the increased rubber-like polymer improves the impact resistance but decreases the gloss. . On the other hand, the gloss can be improved by lowering the content of the rubber-like polymer or by making the particles of the rubber-like polymer dispersed in the resin finer, but the impact resistance is significantly reduced. .

As described above, since impact resistance and gloss are contradictory to each other, it is extremely difficult to obtain an impact resistant styrene resin composition which maintains high gloss and has excellent impact resistance. Conventionally, as a method of improving impact-resistant styrene-based resin, the solution viscosity of the conjugated diene-based polymer has been specified (Japanese Patent Publication No.
8-4934), specification of the relationship between solution viscosity and Mooney viscosity of conjugated diene polymer (Japanese Patent Publication No. 53-4418).
No. 8), specification of the relationship between the solution viscosity of the conjugated diene polymer and the tensile elastic modulus and swelling degree of the crosslinked organic peroxide (Japanese Patent Laid-Open No. 60-25001).

Further, in Japanese Patent Publication No. 59-19577, a conjugated diene system in which a conjugated diene is polymerized using an organolithium-based catalyst containing a polyfunctional organolithium compound and coupled with a polyfunctional treating agent is disclosed. A method using a polymer has been proposed. However, these methods have not always been satisfactory in improving the balance between impact resistance and gloss. Further, the conjugated diene-based polymers used in these methods are all polymers that have been coupled with a polyfunctional treating agent, and a coupling step is required when producing the conjugated diene-based polymer. However, this is an unfavorable direction for increasing production efficiency.

[0006]

As described above, since impact resistance and gloss are contradictory properties, it is not possible to improve the conflicting balance between excellent impact resistance and excellent gloss to a satisfactory degree. Although difficult, the present invention is to solve the above-mentioned problems, and using an uncoupled conjugated diene polymer, the impact-resistant styrene is excellent in the balance of physical properties of impact resistance and gloss. The purpose is to obtain a resin composition.

[0007]

DISCLOSURE OF THE INVENTION In the present invention, as a result of detailed examination of obtaining an impact-resistant styrenic resin having an excellent balance of impact resistance and gloss physical properties, it has not been examined as a conventional toughening agent. The specific conjugated diene polymer, that is, the residue of the catalyst in which the molar ratio of polyvinyl aromatic compound and lithium (polyvinyl aromatic compound / lithium) is adjusted within a specific range is attached to the end of the conjugated diene polymer. It was revealed that the above-mentioned object can be achieved by using the polymer described above, and the present invention has been completed.

That is, in the present invention, at least one conjugated diene-based monomer and, if necessary, at least one aromatic vinyl-based monomer are used in a molar ratio of a polyvinyl aromatic compound and an organic lithium compound (polyvinyl). Aromatic compound /
Lithium) is adjusted in the range of 0.1 to 2.0, and solution polymerization is performed in the presence of an organic lithium-based catalyst, and the polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography is 80 to 650,000. 2 to 25% by weight of a conjugated diene-based polymer in the range of 1 to 5, and an impact-resistant styrene-based resin composition, and at least one conjugated diene-based monomer, and at least one if necessary. An organic lithium base material in which the aromatic vinyl-based monomer (1) is adjusted in a molar ratio of a polyvinyl aromatic compound and an organic lithium compound (polyvinyl aromatic compound / lithium) in the range of 0.1 to 2.0. A conjugated diene obtained by solution polymerization in the presence of a catalyst and having a polystyrene-equivalent weight average molecular weight of 80 to 650,000 as measured by gel permeation chromatography. 98 to 75% by weight of a mixture of 2 to 25% by weight of a styrene-based polymer and a styrene-based monomer or a monomer copolymerizable with the styrene-based monomer is subjected to a bulk polymerization method, a bulk suspension polymerization method or a solution weight method. Provided is a method for producing an impact-resistant styrene resin composition, which is characterized by legally radically polymerizing.

Hereinafter, the present invention will be described in detail. The conjugated diene-based polymer used in the present invention comprises at least one conjugated diene-based monomer and, if necessary, at least one aromatic vinyl-based monomer, a polyvinyl aromatic compound and an organolithium compound in a molar ratio. The ratio (polyvinyl aromatic compound / lithium) was adjusted in the range of 0.1 to 2.0,
It can be produced by solution polymerization in the presence of an organolithium-based catalyst.

The conjugated diene-based monomer used in the present invention includes 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene,
3-Methyl-1,3-pentadiene, 1,3-heptadiene, 1,3-hexadiene, etc., which may be used alone or in combination of two or more. Examples of preferable monomers include 1,3-butadiene and isoprene. In addition, examples of the aromatic vinyl-based monomer used in the present invention include styrene, p-methylstyrene, α-methylstyrene, and 3,5.
-Dimethylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, etc., which may be used alone or in combination of two or more. Particularly, styrene is preferred.

Examples of the hydrocarbon solvent used in the solution polymerization of the present invention include aliphatic hydrocarbons such as butane, pentane and hexane, alicyclic hydrocarbons such as cyclopentane and cyclohexane, and aromatic hydrocarbons such as benzene, toluene and xylene. Hydrogen or the like is used. Preferred examples include hexane and cyclohexane.

Any method can be used to prepare the organolithium-based catalyst used in the present invention as long as it is a reaction between a polyvinyl aromatic compound and an organolithium compound. For example, a reaction between an organolithium compound and a polyvinyl aromatic compound, a reaction between an organolithium compound and a conjugated diene monomer followed by a reaction with a polyvinyl aromatic compound, or a reaction between an organolithium compound and a monovinylaromatic monomer. And then reacting with a polyvinyl aromatic compound, or reacting with an organolithium compound in the presence of a conjugated diene monomer and / or a monovinyl aromatic monomer, and a polyvinyl aromatic compound in the presence of three or four members, etc. The reaction product prepared by the method is used as an organolithium-based catalyst for polymerization.

The term "polyvinyl aromatic compound" as used herein means an aromatic compound having a plurality of vinyl groups, for example, o, m and p-divinylbenzene, o, m and p-.
Diisopropenylbenzene, 1,2,4-trivinylbenzene, 1,2-vinyl-3,4-dimethylbenzene,
1,3-divinylnaphthalene, 1,3,5-trivinylnaphthalene, 2,4-divinylbiphenyl, 3,5
4'-trivinylbiphenyl, 1,2-divinyl-3,
4-dimethylbenzene, 1,5,6-trivinyl-3,
It is 7-diethylnaphthalene or the like, and one kind or two or more kinds can be used. Particularly, divinylbenzene and diisopropenylbenzene are preferable, and these o-, m-, p
It may be a mixture of isomers of-. In the case of industrial implementation, it is economically advantageous to use a mixture of these isomers.

The conjugated diene monomer is 1,3-
Butadiene, isoprene, 2,3-dimethyl-1,3-
Butadiene, 1,3-pentadiene, 3-methyl-1,
3-pentadiene, 1,3-heptadiene, 1,3-hexadiene and the like, and preferable monomers are 1,3
-Butadiene and isoprene. The monovinyl aromatic monomer is styrene, p-methylstyrene, α-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, etc., with styrene being particularly preferred.

Examples of the organolithium compound include mono-organolithium compounds such as n-butyllithium, sec-butyllithium, tert-butyllithium, n-propyllithium, iso-propyllithium and benzyllithium, 1,4-dilithiobutane, and 1. , 5-Dilithiopentane, 1,6-Dilithiohexane, 1,10-Dilithiodecane, 1,1-Dilithiodiphenylene, Dilithiopolybutadiene, Dilithiopolyisoprene, 1,4-Dilithiobenzene, 1,2-Dilithio -1,2-diphenylethane, 1,4-dilithio-2-ethylcyclohexane,
Examples thereof include polyfunctional organolithium compounds such as 1,3,5-trilithiobenzene and 1,3,5-trilithio-2,4,6-triethylbenzene, but preferably n
-Butyl lithium and sec-butyl lithium monoorganolithium compounds are used.

Hydrocarbon solvents used for adjusting the reaction of these organolithium-based catalysts include aliphatic hydrocarbons such as butane, pentane, hexane and heptane, cyclopentane,
Alicyclic hydrocarbons such as cyclohexane and aromatic hydrocarbons such as benzene, toluene and xylene are used. As the organolithium-based catalyst of the present invention, a reaction product using a monoorganolithium compound is preferable, and a reaction of reacting the monoorganolithium compound with a conjugated diene monomer and then reacting with a polyvinyl aromatic compound. The reaction product obtained by reacting the monoorganolithium compound in the presence of the product, the conjugated diene monomer and the polyvinyl aromatic compound is more preferable.

The amount of the polyvinyl aromatic compound used for preparing the organolithium-based catalyst of the present invention is (polyvinyl aromatic compound / lithium) 0.1-2. It is in the range of 0 mol. Preferably, it is in the range of 0.15 to 1.5, more preferably 0.2 to 1.0. A conjugated diene polymer obtained by using an organolithium-based catalyst adjusted to have a polyvinyl aromatic compound / lithium molar ratio of less than 0.1 does not show a significant difference in the effect of the present invention. Impact resistance and gloss are inferior, which is not preferable. When the molar ratio exceeds 2.0, the proportion of the polyfunctional organolithium catalyst in the organolithium-based catalyst increases, and when the catalyst is polymerized, the high molecular weight component in the copolymer is obtained. Is increased, the rubber particle diameters in the resin become uneven, and the resulting gloss in the resin is inferior, which is not preferable.

It is important that the conjugated diene polymer used in the present invention has a residue of the polyvinyl aromatic compound used for the catalyst preparation of the present invention added to the end of the conjugated diene polymer. is there. That is, the present invention is characterized by the fact that the residue of the polyvinyl aromatic compound greatly contributes to exhibiting the effects of the present invention.

The structure of the conjugated diene polymer of the present invention is, for example, a polymer mainly having a structure represented by the following general formula. (1) c-B (2) c-A-B (3) c-B-A (4) c-B-A-B (5) c-A-B-A (6) c-B-A -BA (7) c-ABBAB (In the formula, B is a conjugated diene-based polymer or a block component thereof, or a random copolymer of a conjugated diene and an aromatic vinyl compound or a block component thereof. , A may have a taper block in which the proportion of the aromatic vinyl compound gradually increases. A represents a polymer block mainly containing the aromatic vinyl compound, and c represents a residue of the organolithium-based catalyst.)

Further, a conjugated diene polymer which is one kind or a mixture of two or more kinds of these various structures may be used as a toughening agent for the impact resistant styrene resin composition. Furthermore,
A structure having a structure represented by the following general formula or the like, which is generated by a polyfunctional lithium catalyst in the organolithium-based catalyst, may be mixed.

[0021]

Embedded image (In the formula, B is a conjugated diene polymer or a block component thereof, or a random copolymer of a conjugated diene and an aromatic vinyl compound or a block component thereof, and has a tapered block in which the ratio of the aromatic vinyl compound gradually increases. A may represent a polymer block containing an aromatic vinyl compound as a main component, c represents a residue of an organolithium-based catalyst, and n is an integer of 2 to 6.)

The conjugated diene polymer of the present invention should not be coupled with a commonly used polyfunctional treating agent. Polyvinyl aromatic compound used in the present invention /
The object of the present invention is achieved by adding a catalyst residue of an organolithium-based catalyst in which the molar ratio of lithium is adjusted within a specific range to the conjugated diene polymer. Even after the coupling reaction, the catalyst residue of the organolithium-based catalyst is provided in the conjugated diene polymer, but it is possible to achieve the object of the present invention by increasing the molecular weight, increasing the number of highly branched components, etc. Have difficulty. Also, when producing a conjugated diene polymer,
A coupling step is required, and gelation of the polymer may occur in some cases, which is not preferable in the manufacturing process.

The conjugated diene polymer in the present invention has a slight influence on the impact resistance of the resulting impact-resistant styrene resin composition due to its microstructure. For example, butadiene is used as the conjugated diene monomer. In case 1,
The 2-vinyl content is preferably 10 to 80% and the cis-1,4-content is preferably 10 to 85%, and the 1,2-vinyl content is particularly preferably 12 to 40%. . If a block copolymer having a 1,2-vinyl content outside this range is used, the resulting impact resistant styrene resin will have poor impact strength.

There is no particular limitation on the method for adjusting the 1,2-vinyl content, and any conventional method can be used. For example, when polymerizing a conjugated diene polymer, dimethyl ether, diethyl ether, Tetrahydrofuran (THF), bis (2-oxolanyl) ethane, 2,2-bis (oxolanyl) propane, 1,1-
It is achieved by adding ethers such as bis (oxolanyl) ethane; amines such as dimethylamine; thioethers such as dimethyl sulfide and diethyl sulfide, and performing polymerization.

Further, hexamethylphosphoramide (HM
PA) (Japanese Patent Publication No. 43-5904), a method of adding tetramethylethylenediamine (TMEDA) (Japanese Patent Publication No. 42-17199), a method of adding diethylene glycol dimethyl ether, and the like. Further, the 1,2-vinyl bond may be polymerized so as to be uniform in the molecular chain, or
Polymerization may be performed so as to gradually change along the molecular chain (Japanese Patent Publication No. 47-875), and further, polymerization may be performed so as to form a block-like bond (US Pat. No. 33018).
No. 40).

In order to polymerize 1,2-vinyl bonds so that they are uniform in the molecular chain, the polymerization initiation temperature is usually 30 to 90.
C., a method of performing isothermal polymerization as much as possible is adopted, and in order to polymerize the 1,2-vinyl bond so as to gradually change along the molecular chain, a method of performing the polymerization at an elevated temperature, That is, usually, a method of setting the polymerization start temperature to 30 to 80 ° C. and a polymerization end temperature of 85 to 120 ° C., a method of gradually adding the 1,2-vinyl content modifier during the polymerization, and the like are adopted. .

When the conjugated diene polymer of the present invention is a copolymer comprising a conjugated diene monomer and a monomer copolymerizable therewith, the content of the copolymerizable monomer or the copolymerization The chain distribution of the copolymerizable monomer in the united chain is not particularly limited. In addition, the composition distribution of the monomer capable of being copolymerized with the conjugated diene in the copolymer chain may be uniform in the molecular chain, or may be unevenly distributed in the molecular chain, It may exist as a block.

Next, the polystyrene-equivalent weight average molecular weight (Mw) of the conjugated diene polymer of the present invention measured by gel permeation chromatography is limited to the range of 80 to 650,000. It is preferably in the range of 100,000 to 400,000. The ratio Mw / Mn of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is preferably in the range of 1.0 to 3.0.

When the weight average molecular weight of the conjugated diene polymer used is less than 80,000, the impact strength of the resulting impact resistant styrene resin composition is poor. When a conjugated diene polymer having a weight average molecular weight of more than 650,000 is used,
When manufacturing the impact-resistant styrene-based resin, there is a serious problem in the manufacturing process such as a decrease in workability in the process of dissolving a styrene-based monomer in the styrene-based monomer and spending a lot of time for transferring this solution.

The impact-resistant styrenic resin composition of the present invention is a styrenic resin composition containing 2 to 25% by weight of the above-mentioned conjugated diene polymer. When the amount of rubber used is less than 2% by weight, The effect of improving the impact strength targeted by the invention is insufficient, and it is difficult to achieve the object of the present invention. On the other hand, if the amount of use exceeds 25% by weight, the impact strength is improved, but the original properties of the polystyrene resin, such as tensile strength, rigidity, and appearance properties such as gloss, are impaired, which is not preferable. Further, the viscosity of the graft polymerization solution becomes extremely high, and it becomes difficult to produce the impact-resistant styrene resin composition of the present invention.

The average particle size of the conjugated diene polymer particles dispersed in the impact resistant styrene resin composition obtained in the present invention is preferably adjusted to the range of 0.2 to 2.0 μm. The adjustment of the rubber particle diameter of the conjugated diene polymer particles is affected by various factors such as the shape of the stirring device in the polymerization tank, the rotation speed of the stirrer, the stirring time, and the polymerization temperature.
Generally, at the time of producing an impact-resistant styrene resin composition,
The rubber particle size can be adjusted by changing the rotation speed of the stirrer, for example, such that shear stress is applied to the rubber solution.

The method for obtaining the impact-resistant styrenic resin composition of the present invention is not particularly limited as long as consideration is given to satisfy the constitutional requirements of the present invention, and a known method can be used. . Usually, 2 to 25% by weight of the conjugated diene polymer of the present invention and 98 to 75% by weight of a mixture of a styrene monomer or a monomer copolymerizable with the styrene monomer are subjected to a bulk polymerization method or a bulk method. The impact-resistant styrene-based resin composition can be produced by radical polymerization by a suspension polymerization method or a solution polymerization method.

In the bulk polymerization method, which is one of the preferred methods for obtaining the impact-resistant styrene resin composition of the present invention, generally, the conjugated diene polymer of the present invention is first dissolved in styrene to prevent oxidation. Agent, if necessary a chain transfer agent which is a molecular weight modifier, in the case of no catalyst, heat polymerization is usually carried out at a temperature of 95 to 200 ° C., and in catalyst polymerization using a radical initiator as a catalyst, it is lower than usual. , For example 6
The styrene polymerization operation is continued at a temperature of 0 to 180 ° C.

In the case of catalytic polymerization, 1,1 is used as an initiator.
-Bis (t-butylperoxy) cyclohexane, 1,
Peroxyketals such as 1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane; di-t
-Butyl peroxide, 2,5-dimethyl-2,5-
Dialkyl peroxides such as di (t-butylperoxy) hexane and dicumyl peroxide; diacyl peroxides such as benzoyl peroxide, m-toluoyl peroxide and lauroyl peroxide;
Peroxydicarbonates such as dimyristyl peroxydicarbonate and diisopropyl peroxydicarbonate; t-butyl peroxyisopropyl carbonate, t-butyl peroxyacetate, di-t-butyl diperoxy isophthalate, t-butyl percarbonate Peroxyesters such as oxybenzoate; Ketone peroxides such as cyclohexanone peroxide and methyl ethyl ketone peroxide; Hydroperoxides such as p-mentha hydroperoxide, t-butyl hydroperoxide and cumene hydroperoxide; Azobis Azo compounds such as isobutyronitrile and azobiscyclohexanecarbonitrile are used. These are used alone or in combination of two or more.

Examples of the antioxidant include octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate and 2,6-di-t-butyl-4.
-Methylphenol, 2- (1-methylcyclohexyl) -4,6-dimethylphenol, 2,2'-methylenebis (4-ethyl-6-t-butylphenol),
4,4'-thiobis (6-t-butyl-3-methylphenol), 2,4-bis [(octylthio) methyl]-
o-cresol, triethylene glycol-bis [3-
(3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], tris (dinonylphenyl) phosphite, tris- (2,4-di-t-butylphenyl) phosphite, and the like. Resin 1 is added
It is 0.01 to 5 parts by weight, preferably 0.1 to 2 parts by weight, per 00 parts by weight.

As the chain transfer agent, for example, n-dodecyl mercaptan, tert-dodecyl mercaptan, α
-Methylstyrene dimer, 1-phenylbutene-2-
Mercaptanes such as fluorene, dipentene and chloroform, terpenes, halogen compounds and the like can be used. Further, in this bulk polymerization method, it is possible to add an internal lubricant such as liquid paraffin, mineral oil or organic polysiloxane which is usually used, if necessary. For example, polydimethylsiloxane, which is an organic polysiloxane, is added in an amount of 0.005 to 100 parts by weight of the polymer.
You may add 10 weight part.

After the completion of the polymerization, when unreacted styrene is contained in the produced polymer, the styrene is removed by a known method, for example, a method of removing under reduced pressure or an extruder designed for the purpose of removing volatile matter. It is desirable to do. During the bulk polymerization, stirring can be carried out if necessary, but it is desirable to stop or moderate the stirring after the conversion of styrene to the polymer, that is, after the polymerization rate has advanced by 60% or more, Stirring may reduce the strength of the resulting polymer. If necessary, the polymerization may be carried out in the presence of a small amount of a diluent such as toluene or ethylbenzene, and after completion of the polymerization, these diluents may be removed by heating together with unreacted styrene.

The bulk suspension polymerization method is also useful for producing the impact resistant styrene resin composition of the present invention. In this method, the first half polymerization is first carried out by the bulk polymerization method, and the second half reaction is suspended. The turbid polymerization method is used. That is, the styrene solution of the conjugated diene polymer of the present invention is subjected to heat polymerization or catalyst addition polymerization in the absence of a catalyst as in the case of the above-mentioned bulk polymerization method, and usually 50% or less of styrene is particularly preferable. ~
Up to 40% are partially polymerized by the bulk polymerization method and then the partially polymerized mixture is dispersed in the aqueous medium with stirring in the presence of a suspension stabilizer or a combination of this with a surfactant. The second half of the reaction is completed by the suspension polymerization method.

The produced polymer is washed, dried and, if necessary, pelletized or powdered before use. In addition to the above-mentioned methods, a useful impact-resistant styrene-based resin composition can be obtained by a conventionally known method which is an improvement or improvement of these methods. Further, a part of styrene forming the impact resistant styrene resin composition together with the conjugated diene polymer of the present invention may be replaced with a monomer capable of radical polymerization with styrene other than styrene. The monomer is used in the range of 50% by weight or less based on the total monomers including styrene.

The copolymerizable monomer other than styrene is selected from the group of vinyl aromatic compounds, vinyl cyanide compounds, (meth) acrylic acid esters and other copolymerizable monomers. . Examples of vinyl aromatic compounds include α-methylstyrene, p-methylstyrene,
Vinylethylbenzene, vinylxylene, vinylnaphthalene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene, tetrabromostyrene, fluorostyrene, 1,1-diphenylethylene,
Examples thereof include divinylbenzene, p-hydroxystyrene, o-methoxystyrene, vinylpyridine, etc., and α-methylstyrene is preferable.

Examples of vinyl cyanide compounds include acrylonitrile and methacrylonitrile, with acrylonitrile being preferred. Examples of (meth) acrylic acid ester include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, dodecyl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate methacrylate, butyl methacrylate. , Amyl methacrylate, hexyl methacrylate, octyl methacrylate, dodecyl methacrylate, cyclohexyl methacrylate and the like, with methyl methacrylate being preferred.

Other copolymerizable monomers include conjugated dienes such as butadiene and isoprene.
These monomers may be used alone or in combination of two or more. The impact-resistant styrene resin composition thus obtained had a gel content (toluene insoluble content) of 10
Is preferably in the range of 40 to 40% by weight, the swelling index of the gel in the resin composition in toluene is preferably in the range of 7 to 13, and the molecular weight of the resin portion is usually 100,000 to 400,000 in terms of weight average molecular weight. , And more preferably 15 to 30
Range of ten thousand. The amount of the styrene oligomer remaining in the resin affects the heat resistance, so that it is usually preferably 1% by weight or less, and particularly preferably 0.5% by weight or less when heat resistance is required.

Upon further processing, if necessary, various additives such as an antioxidant, an ultraviolet absorber, a flame retardant, a lubricant, a release agent, a filler, an organic polysiloxane, and other thermoplastic resins such as general-purpose ones. Polystyrene, AS resin, ABS resin, AES resin, MBS resin, styrene-butadiene methacrylic resin, polyphenylene ether, polycarbonate, styrene-butadiene copolymer, methyl methacrylate / styrene copolymer resin, maleic anhydride / styrene copolymer resin , Polyamide resin, polyester resin, etc. may be mixed. Addition of these resins imparts heat resistance, rigidity, impact resistance, appearance, paintability, etc. and is used depending on the application.

The impact-resistant styrenic resin composition of the present invention can be molded into a wide variety of practically useful products by molding by processing methods such as injection molding and extrusion molding. It is used in a wide variety of applications such as electric appliances, cabinets for OA equipment, housings, interior / exterior parts for automobiles, parts for housing / furniture, antenna parts for broadcasting / communication, and others.

[0045]

EXAMPLES Some examples will be shown below to show concrete embodiments of the present invention, but this is for more specifically explaining the technical contents of the present invention, and does not limit the present invention in any way. Not something to do. Further, various measurements were made by the following methods. [Weight Average Molecular Weight of Polymer] This is a polystyrene-equivalent molecular weight measured and calculated by GPC (gel permeation chromatography).

(GPC measurement conditions) Measurement model LC Module1 solvent manufactured by Waters, THF (tetrahydrofuran) column ZORBAX PSM1000S × 2 tubes manufactured by DuPont PSM60S × 1 tube (total 3 tubes) Column temperature 35 ° C Liquid transfer flow rate 0.7 ml / min Sample concentration 0.1% by weight Sample injection amount 0.1 ml Detector Showa Denko Shodex RI SE-61

[Microstructure] Using an infrared spectrophotometer,
Hampton Method [Analytical Chemist
ry, 21, 923 (1949)]. [Izod impact strength] The obtained composition was compression-molded to prepare a 3.2 mm-thick test piece, which was subjected to JIS-K-7.
Measured according to 110.

[Glossiness] Glossiness (incident angle 60 °) of the gate portion and the end gate portion was measured and averaged according to ASTM D-638. [Rubber particle diameter] The rubber particles were measured by the Coulter counter method, and the obtained value was expressed as 50% median diameter.

(Examples 1 to 18 and Comparative Examples 1 to 10) (1) Preparation of catalyst An autoclave equipped with a stirrer and a jacket having an internal volume of 10 l was washed and dried, and after nitrogen replacement, under the conditions shown in Table 1. Then, dried 1,3-butadiene, cyclohexane and divinylbenzene were added, and then n-butyllithium was added and reacted at 75 ° C. for 1 hour for adjustment. The organolithium-based catalyst prepared under the conditions shown in Table 1 was soluble in cyclohexane and had no gel at all.

The divinylbenzene used to prepare the catalyst is
56% by weight of an isomer mixture (m-divinylbenzene = 40
%, P-divinylbenzene = 16% by weight), and the commercially available divinylbenzene was used, the balance being ethylvinylbenzene and diethylbenzene. The catalyst F was prepared in the same manner as described above except that m-diisopropenylbenzene was used instead of divinylbenzene.

(2) Production of conjugated diene polymer An autoclave equipped with a stirrer and a jacket having an internal volume of 10 l was washed and dried, and after purging with nitrogen, 700 g of 1,3-butadiene and cyclohexane 5000 which had been purified and dried in advance.
g, and then tetrahydrofuran as a 1,2-vinyl modifier, and the organolithium-based catalyst shown in Table 1 was further added to initiate polymerization at 65 ° C. The polymerization temperature rose to about 100 ° C. After the completion of the polymerization, methanol was added to completely deactivate the living polymer. To the polymer solution thus obtained, 0.5 part by weight of 2,6-di-tert-butyl-4-methylphenol was added as a stabilizer per 100 parts by weight of the polymer, and the solvent was removed by steam stripping. , After dehydration, followed by drying with a hot roll (110 ° C.), Table 2,
Rubber sample Nos. Shown in Table 3 1 to 25 conjugated diene polymer was obtained.

(3) Production of Impact-Resistant Styrenic Resin Composition Next, using various conjugated diene-based polymers shown in Tables 2 and 3, the impact-resistant styrene-based resin composition is prepared by the following bulk polymerization method. A resin composition was obtained. Ethylbenzene and styrene were added to the stirrer and the reactor equipped with the jacket in the types and proportions shown in Tables 4 and 5, and then the conjugated diene polymer sample Nos. Shown in Tables 2 and 3 were added. N-octadecyl-3- (3 ', 5'-di-ter as a rubber and a stabilizer of
0.3 parts by weight of t-butyl-4'-hydroxyphenyl) propionate and 0.05 parts by weight of t-dodecyl mercaptan were added and dissolved by stirring.

Di-tert-butyl peroxide was added ^{thereto in} an amount of 1 × 10 ^-4 mol per 1 mol of the monomer,
Polymerization was performed at 110 ° C. for 3 hours, 140 ° C. for 5 hours, and 180 ° C. for 2 hours. Further, after heating at 230 ° C. for 30 minutes, the unreacted product was removed under reduced pressure, the obtained polymer was ground, and in some cases mineral oil and polydimethylsiloxane having a viscosity of 500 centistokes at 25 ° C. were added, Pelletized with an extruder.

During the reaction, the average particle size of the rubber particle phase is about 1
The stirring number was controlled so as to be about 1.3 μm.
The physical properties of the obtained impact-resistant styrene resin composition are
The results are shown in Tables and 5. It can be seen that the impact resistant styrene resin composition produced using the conjugated diene polymer of the present invention is excellent in the balance between Izod impact strength and gloss. On the other hand, as shown in Comparative Examples 1 to 10, when a conjugated diene polymer outside the scope of the present invention is used, impact strength or gloss is inferior, and both are excellent impact-resistant styrene resin compositions. Was not obtained.

Examples 19 to 21 Using the same reactor as in Example 1, ethylbenzene, styrene and acrylonitrile were added in the types and proportions shown in Table 5, and then shown in Tables 2 and 3. Conjugated diene polymer sample No. N-octadecyl-3- (3
0.3 parts by weight of ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate and 0.05 parts by weight of t-dodecyl mercaptan were added and dissolved by stirring.

To this, 1 × 10 ⁻⁴ mol of di-tert-butyl peroxide was added to 1 mol of the monomer, and 1
Polymerization was carried out at 10 ° C. for 3 hours, 140 ° C. for 5 hours, and 180 ° C. for 2 hours. After heating at 230 ° C for 30 minutes,
The unreacted product was removed under reduced pressure, and the obtained polymer was pulverized and pelletized with an extruder to obtain an ABS resin. During the reaction,
The stirring number was controlled so that the average particle size of the rubber particle phase was about 1.0 μm. Table 5 shows the physical properties of the obtained ABS resin composition.

(Examples 22 and 23) Using the same reactor as in Example 1, ethylbenzene, styrene and methylmethacrylate were added in the types and proportions shown in Table 5, and then in Tables 2 and 3. Conjugated diene polymer sample No. shown.
N-octadecyl-3-as a rubber and stabilizer of
0.3 parts by weight of (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate and 0.05 parts by weight of t-dodecyl mercaptan were added and dissolved by stirring.

To this, 1 × 10 ⁻⁴ mol of di-tert-butyl peroxide was added to 1 mol of the monomer, and 1
Polymerization was carried out at 10 ° C. for 3 hours, 140 ° C. for 5 hours, and 180 ° C. for 2 hours. After heating at 230 ° C for 30 minutes,
The unreacted product was removed under reduced pressure, and the obtained polymer was pulverized and pelletized with an extruder to obtain an MBS resin. During the reaction,
The stirring number was controlled so that the average particle size of the rubber particle phase was about 1.0 μm. Table 5 shows the physical properties of the obtained MBS resin composition.

Comparative Example 11 (1) Production of Conjugated Diene Polymer An autoclave equipped with a stirrer and a jacket having an internal volume of 10 l was washed and dried, and after purging with nitrogen, 700 g of 1,3-butadiene and cyclohexane which had been purified and dried in advance were replaced. 5000
Then, 1.2 g of tetrahydrofuran as a 1,2-vinyl modifier was added, and then an organolithium-based catalyst A was further added to initiate polymerization at 65 ° C. The polymerization temperature rose to about 100 ° C. After completion of the polymerization, silicon tetrachloride was added to the obtained polymer as a polyfunctional coupling agent, and the reaction was carried out for 30 minutes.

To the polymer solution thus obtained, as a stabilizer, 2,6-di-tert-butyl-4-methylphenol was added in an amount of 0.5 part by weight per 100 parts by weight of the polymer, and the solvent was removed by steam stripping. Was removed, dehydrated, and subsequently dried by a hot roll (110 ° C.) to give a rubber sample No. 1 shown in Table 2. 26 conjugated diene-based polymers were obtained.

(2) Production of Impact-Resistant Styrenic Resin Composition Rubber sample No. 1 was prepared in the same manner as in Example 1. An impact resistant styrene-based resin composition was obtained by using 26 rubbers. No impact styrenic resin composition excellent in both impact strength and gloss was obtained.

Comparative Example 12 Rubber sample No. 1 was prepared in the same manner as in Example 1 except that n-butyllithium was used as the polymerization catalyst. 27 conjugated diene-based polymers and impact resistant styrene-based resin compositions were obtained. The impact-resistant styrene-based resin composition produced using a conjugated diene-based polymer obtained by using n-butyllithium, which is a common polymerization catalyst, is
It can be seen that the balance of Izod impact strength and gloss is poor.

[0063]

[Table 1]

[0064]

[Table 2]

[0065]

[Table 3]

[0066]

[Table 4]

[0067]

[Table 5]

[0068]

[Table 6]

[0069]

INDUSTRIAL APPLICABILITY The impact-resistant styrenic resin composition of the present invention has an excellent physical property balance between impact resistance and gloss as compared with the conventional impact-resistant styrene resin composition, and can be used in electronic devices such as TVs and VTRs. Home appliances such as appliances, air conditioners and refrigerators, OA
It has an industrially superior effect that it can be used in a wide variety of applications such as general equipment such as office equipment, stationery, toys, leisure sports goods, household goods, building materials and housing parts, and food containers.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C08F 297/04 MRE C08F 297/04 MRE C08L 25/04 LDT C08L 25/04 LDT

Claims (2)

[Claims] 1. A molar ratio (polyvinyl aromatic compound / lithium) of a polyvinyl aromatic compound and an organolithium compound of at least one conjugated diene-based monomer is 0.1.
The polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography is in the range of 80 to 650,000, which is obtained by solution polymerization in the presence of an organolithium-based catalyst adjusted in the range of 2.0 to 2.0. An impact-resistant styrene-based resin composition containing 2 to 25% by weight of a conjugated diene-based polymer. 2. A molar ratio (polyvinyl aromatic compound / lithium) of a polyvinyl aromatic compound and an organic lithium compound of at least one conjugated diene-based monomer is 0.1.
The polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography is in the range of 80 to 650,000, which is obtained by solution polymerization in the presence of an organolithium-based catalyst adjusted in the range of 2.0 to 2.0. 98 to 75% by weight of a mixture of 2 to 25% by weight of a conjugated diene polymer and a styrene monomer or a monomer copolymerizable with the styrene monomer.
A method for producing an impact-resistant styrene-based resin composition, wherein and are radically polymerized by a bulk polymerization method, a bulk suspension polymerization method, or a solution polymerization method.