JPS60250021A - Impact-resistant styrene resin containing low-modulus rubber - Google Patents

Abstract

PURPOSE:The title styrene resin having excellent Izot impact strength and good ridity and suited for use in vehicle parts, etc., obtained by dissolving a specified conjugated diene polymer rubber of a low elastic modulus in styrene and polymerizing the solution. CONSTITUTION:A conjugated diene monomer is polymerized in the presence of a small amount of a polyvinyl aromatic compound by using an organolithium compound as a catalyst, and the formed polymer is subjected to a coupling reaction with a polyfunctional treating agent. In this way, a conjugated diene polymer rubber which satisfies the relationship I (wherein etas (cp) is a viscosity of a 5wt% styrene solution of the conjugated diene polymer at 25 deg.C, E (kg/cm<2>) is a tensile modulus of a cured product obtained by crosslinking the conjugated diene polymer with an organic peroxide, and S is the degree of swelling) is produced. This rubber is dissolved in styrene and polymerized to form the title styrene resin satisfying the relationship II (wherein G is a toluene-insoluble matter content and R is a conjugated diene polymer rubber content).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to impact-resistant styrenic resins using low modulus rubber, and more specifically, to the use of specific conjugated diene polymer rubbers having low modulus as toughening agents. The present invention relates to a styrenic resin used as a styrene resin having excellent impact resistance, particularly Izot impact strength, and good rigidity.

BACKGROUND OF THE INVENTION Polystyrene resins are widely used for various purposes because they have excellent rigidity, transparency, gloss, and good moldability. However, this polystyrene resin has a major drawback of poor impact resistance.Therefore, methods to improve this drawback include, for example, mechanically blending a rubbery polymer with polystyrene, or adding a styrene solution of a rubbery polymer. Methods such as bulk polymerization or bulk suspension polymerization have been proposed. Particularly, the method of bulk polymerization or bulk suspension polymerization is widely practiced industrially because the obtained polymer has excellent physical properties. In such methods, rubber-like polymers used as toughening agents include polybutadiene rubber and styrene-butadiene copolymer rubber.
．． In particular, polybutadiene rubber is widely used because it provides excellent impact resistance.

In recent years, impact-resistant styrene resins have been used in housings and parts for household electrical equipment, axle parts, parts for office equipment,
As materials become more widely used in daily necessities, toys, etc., various superior properties are required, and impact resistance and rigidity are the fundamental physical properties that are strongly demanded to be improved.

As is well known, impact resistance can be improved by increasing the content of rubbery Na bodies, but the viscosity of styrene solutions containing high concentrations of rubbery polymers increases significantly, making industrial production difficult. In addition to being unfavorable in terms of transportation and agitation, styrenic resins with increased comb-like polymers have improved impact resistance, but have significantly lower rigidity, resulting in weak resins.

On the other hand, the rigidity can be improved by lowering the content of the comb-like polymer or by making the particles of the comb-like polymer dispersed in the resin finer, but on the other hand, the impact resistance is significantly reduced. .

As described above, since impact resistance and rigidity are contradictory properties, it is difficult to obtain a styrenic 1θ chili resin that maintains high rigidity and also has excellent impact resistance.

Conventionally, two methods have been known for improving 11fIJ impact styrene resin: improving the comb-like elastic body used and improving the resin. Examples of improvement methods include specifying the microstructure of a comb-like polymer (Japanese Patent Publication No. 52-86444, Japanese Patent Publication No. 53-44188), and specification of solution viscosity (Japanese Patent Publication No. 58-4934). Publication), specification of the relationship between solution viscosity and Mooney viscosity (Japanese Patent Publication No. 53-44188, Japanese Patent Publication No. 58-4934@), specification of molecular weight distribution (Japanese Patent Publication No. 2 of 159-198), etc. method has been proposed.

Problems to be Solved by the Invention However, these methods are not always satisfactory in terms of improving impact resistance, especially Izot impact strength, and improving rigidity without increasing the amount of rubbery polymer. isn't it.

In view of these circumstances, the present inventors have conducted repeated research on rubber-like polymers that provide impact-resistant styrenic resins that have excellent isotonic impact strength and rigidity. It was found that there is a deep relationship with the specific elastic modulus.

Generally, the elastic modulus of rubber changes depending on the molecular weight, molecular weight distribution, degree of branching, etc. of the rubber, and also changes depending on the degree of crosslinking, crosslinked structure, etc. Well, the elastic modulus of rubber E (K
9/cvi) f, the solution viscosity ηe (cps) when all of the rubber is dissolved in a specific solvent, and the swelling degree S of the crosslinked product of the rubber in a specific solvent, generally the elastic modulus E of the rubber is η8 There is a relationship that the smaller the degree of swelling S is, the smaller it is, and the larger the degree of swelling S is, the smaller it is.

Therefore, the present inventors conducted a detailed study on the tensile modulus E of the conjugated diene polymer rubber and the Izot impact strength and rigidity of the impact-resistant styrenic resin using the rubber. The elastic modulus is low,
That is, the viscosity η. , tensile elasticity, and swelling degree S under a certain value ↓ It has been found that in a specific case, the resin has an impact strength of 40% and a rigidity of 4.5%, and the present invention has been completed based on this finding.

Means for solving the problems, ie, the present invention ii, a rain shock-resistant method comprising dissolving a conjugated diene polymer rubber obtained by solution polymerization in the presence of an organolithium compound in styrene and polymerizing the solution. 5N amount % styrene solution viscosity η5 (cps) of the conjugated diene polymer rubber measured at a temperature of 25° C.
and the tensile modulus E (Ky/ca) and swelling degree S of the organic peroxide crosslinked product of the conjugated diene polymer, the relationship of the formula η6 K, S≦20,000 -1-(+1) is established. , and the weight ratio of the content G of toluene insoluble matter in the resin to the conjugated diene content R (content R of the combined rubber)
The present invention provides an impact-resistant styrenic resin using a low elastic modulus rubber characterized in that /R satisfies the following relationship.

The impact-resistant styrenic resin of the present invention has a specific conjugated diene polymer rubber having a low modulus of elasticity of 1. By using it as a total toughening agent, compared to the case where conventional conjugated/ene polymer rubber is used. This completely breaks the conventional wisdom that even though they have the same microstructure, they have excellent Izotsu impact strength and rigidity, and have extremely innovative properties.

The conjugated diene used in the present invention is a conjugated diene having 94 to 12 carbon atoms f7 per molecule, such as 1.3-butadiene, isogrene, 2,3-dimethyl-1,3-butadiene, piperylene, 1, 3-octadiene, 4,5-
1,3-octasienna, etc., but especially 1
．． 3-butadiene is preferred.

Further, the conjugated diene polymer comb is a homopolymer rubber or a copolymer rubber of two or more types of the conjugated diene. Particularly preferred are polybutadiene rubber, polyisoprene comb and butadiene-isoprene copolymer comb,
Most preferred is polybutadiene rubber.

In the unexploded BA, the specific conjugated diene polymer comb used has a low elastic modulus, and the tensile modulus was used as this elastic modulus.The tensile modulus E here refers to the conjugated diene polymer comb About 0.02 to about 0.2 parts by weight of organic peroxide/cumyl peroxide was added to 1001 parts of polymer rubber and kneaded. The tensile modulus of the perky crosslinked material obtained by compression molding for 1 minute is expressed as 9/crI.

The tensile modulus E is JI, which is punched from a 2 mm thick peroxide crosslinked sheet obtained by compression molding as described above.
The stress obtained when a tensile test was conducted using a No. 83 dumbbell-shaped test piece at room temperature with a Tensilon tensile tester (manufactured by Toyo Baldwin) at a tensile rate of 50/min.
The initial slope of the strain curve was determined.

Further, the degree of swelling S in the present invention was determined as follows. That is, the peroxide cross-linked product 27 was weighed, immersed in 50 rnl of toluene and swollen for 3 hours, and then this swollen product was separated from the solvent with a 1100 mesh wire mesh filter, and the sample was adhered to the surface of the sample. When the solvent in the gel was evaporated, the weight was measured (Wet Gel Weight), then the solvent was completely removed by heating and vacuum drying, and the weight was measured again (Dry Gel Weight), and the degree of swelling S was calculated using the following formula.

Here, the degree of swelling of the rubber varies depending on the amount of peroxide added. That is, as the amount of peroxide added increases, the degree of swelling decreases, and correspondingly, the tensile modulus decreases. Therefore, the swelling degree and tensile modulus of rubber are not necessarily determined. However, it has been experimentally found that the product of the degree of swelling S and the tensile modulus E is almost constant and is determined by the type of rubber. Therefore, in order to determine the degree of swelling and tensile modulus, an appropriate degree of swelling must be determined.
It is necessary to calculate the tensile modulus at that time.

For convenience of measurement, it is preferable to use one degree of swelling (ri) in the range of about 1 to about 14. (The tensile elastic modulus at that degree of swelling is calculated from the total index of wetness index divided by 1, which is calculated from the weight of raw styrene resin, and then the ratio of 1 unit of swelling to 1 unit of tensile elastic modulus.)

In the present invention, the co-immersed tsene polymer rubber with a low elastic modulus is defined by the tensile modulus K (K9/crl), the degree of swelling S corresponding to the tensile modulus, and the The 5 wt% styrene solution viscosity of the comb itself η8 (cps
) is 20000.1 no, the one below, ie.

It means something that satisfies the relationship of formula (1) above. here,
The tensile modulus E of the conjugated diene polymer rubber has a correlation with η8. That is, there is a relationship in which a comb with a small η6 has a small tensile modulus E.

In the present invention, it is more preferable that η8·E−S is less than tsooo Q, and a conjugated diene polymer rubber having Pl·S of 200 or less is further suitable. When η8·gs exceeds 20,000, the effect of improving the isot impact strength and rigidity of the resulting impact-resistant styrenic resin is small.

The specific conjugated diene TOGOGAI COMB used in the present invention is solution polymerized using an organolithium compound as an all-catalyst. This organic lithium compound is a hydrocarbon having at least one lithium atom bonded in its molecule, and examples of such compounds include n-glopyllithium, inopropyllithium, n-butyllithium, and 5eC-butyllithium. , tert-butyllithium, n-pentyllithium, lithium toluene, benzyllithium, 1.4
-dilithio-〇-butane, 1,2-dilithio-1,2-
Examples include di-phenylethane, trimethylene lithium, etc. Particularly common ones include n-butyl lithium,
5eG-butyllithium or the like is used.

The conjugated diene polymer rubber used in the present invention has a slight influence on the Izo impact strength of the resulting impact-resistant styrenic resin depending on its microstructure. For example, when using polybutadiene rubber as the conjugated diene polymer rubber,
Preferably, the 1,2-vinyl content is 10-35% and the 1.4-vinyl content is 20-85%. If a polybutadiene rubber having a microstructure outside this range is used, the resulting impact-resistant styrenic resin will have poor cylindrical strength and poor impact resistance (IZ).

There is no particular restriction on the method for adjusting the 1,2-vinyl content, and any conventionally known method can be used. For example, when polymerizing conjugated diene polymer rubber, this can be achieved by adding ethers such as dimethyl ether, diethyl ether, and tetrahydrofuran, amines such as dimethylamino, dimethyl sulfide, and diethyl sulfitone to the polymerization system. .

Furthermore, a method of adding hexamethylphosphoramide (HMPA') (Japanese Patent Publication No. 13-5904), a method of adding tetramethylethylenediamine (TMKDA) (Patent Publication No. 42-17199), and a method of adding diethylene glycol dimethyl ether There are ways to do this. In addition, the 1,2-vinyl bond may be polymerized so that it is uniform throughout the molecular chain, or it may be polymerized so that it changes gradually along the molecular chain.
(U.S. Pat. No. 48-875) Furthermore, it may be combined in a block manner (U.S. Pat. No. 330-875).
1840 specification). 1. In order to polymerize the 2-vinyl bonds uniformly in the molecular chain, the polymerization initiation temperature is usually set to 3.
A method is used in which the temperature is set at 0 to 90° C. and constant temperature polymerization is carried out.

In addition, in order to polymerize so that the 1,2-vinyl bond gradually changes along the entire molecular chain, the polymerization is carried out at an elevated temperature, that is, the polymerization initiation temperature is usually set at 30 to 80 °C, A method is used in which the temperature at the end of one cup is 85 to 120°C.

The conjugated diene polymer comb used in the present invention has an SV of 1
It is preferably in the range of 5 to 100 cps.

If this SV is less than 15 cps, the resulting impact-resistant styrenic resin will have poor isot impact strength, and it will be difficult to dry the conjugated diene polymer rubber during packaging, and the cold flow of the product will be reduced. It is industrially disadvantageous.

In order to produce such conjugated diene polymer rubber,
Some kind of improvement is necessary. As a specific method, for example, when total polymerizing a conjugated diene monomer using an organolithium compound as a catalyst, a small amount of a polyvinyl aromatic compound is interposed, and after the polymerization of the monomer is substantially completed, Examples of methods include producing a pin polymer or coupling a pin polymer with a polyfunctional processing agent.

Incidentally, a method of polymerizing a conjugated diene monomer in the coexistence of a polyvinyl aromatic compound using an organolithium compound as a catalyst is known (for example, in W Komei No. 43-25510). However, this method does not directly apply to the present invention. It was not possible to obtain the conjugated diene polymer rubber to be used, and by further coupling reaction with a polyfunctional treatment agent, a conjugated diene polymer with a special branched structure and a low elastic modulus that can be used in the present invention was obtained for the first time. rubber is obtained.

As another example, conjugated diene monomers ff,i are polymerized using a mixture of a mono-organolithium compound and a di- or tri-organolithium compound as a catalyst, with a small amount of polyvinyl aromatic compound intervening, and the polymerization is substantially After completion of the process, the resulting polymer is subjected to a coupling reaction using a polyfunctional processing agent.

Further, using a reaction product containing at least an organolithium compound and a polyvinyl aromatic compound as a catalyst, a conjugated diene monomer is polymerized with a slight amount of a polyvinyl aromatic compound interposed, and after the polymerization is substantially completed, There is a method in which the generated or pinged polymer is subjected to a coupling reaction with a polyfunctional processing agent.

Polyvinyl aromatic compounds referred to in Komu include, for example, hashivinylbenzene, 1,2.4-) IJ vinylbenzene,
1.3-divinylnaphthalene, 1,3.5-)divinylnaphthalene, 2.4-divinylbiphenyl, 3°5.4
-) ribinyl biphenyl and the like, preferably divinylbenzene. This divinylbenzene has o-, m
There are - and p- isomers, and divinylbenzene, which is a mixture of these isomers, is commercially available, and the effect can be sufficiently exerted even when this is used.

On the other hand, examples of polyfunctional processing agents include silane compounds [J.

Polym, Sci., A-1, 3, 93 (1965
)), diesters such as adipic acid/ether (British Patent No. 1223079), carbonic diesters such as diethyl carbonate (Japanese Patent Publication No. 54-8716, divinyl aromatic compounds such as nilbenzene (% 5
1-34290), carbon, halides such as chloroform and dibromoethane, and tin compounds such as tetrachlorotin and methyltrichlorotin, all known compounds can be used.

These may be used alone or in combination of two or more.

Regarding the molecular weight distribution of the conjugated diene polymer rubber obtained in this way, the molecular weight distribution curve of APC (gel permeation chromatography) may be monomodal, bimodal, trimodal, etc. May be polymodal.

Furthermore, M weight average molecular weight (iW) and number average molecular weight (in
>< mw7yn ) is usually in the range of 1.2 to 4.5.

In order to achieve all the objects of the present invention in the impact-resistant styrenic resin obtained using the specific conjugated diene polymer rubber of the present invention, it is necessary to The weight ratio with the rubber content R is
It is necessary to have a ratio that satisfies the formula % formula %. If the G/R value is less than 1.5, the resin will have poor Izotsu cylindrical strength and rigidity, and if it is more than 3 or 5, the rigidity will be poor. Although it can be maintained, the Izotsu impact strength is inferior.

The adjustment of the G/R value is usually performed by adjusting the G value. This G value is adjusted by controlling the amount of the polymerization initiator added, the polymerization temperature, or both in the polymerization of the impact-resistant styrenic resin. That is, the G value can be increased by increasing the amount of initiator added during the N interval, by lowering the polymerization temperature, or by doing both. Particularly effective is the method of increasing the amount of polymerization initiator.

The rubber particle diameter in the impact-resistant styrene resin of the present invention is in the range of 0.5 to 5 μm, usually 1.11.5 to 3 μm.

Especially for high gloss grade and 1-1 iZt, 7-1.5
A range of μ is preferred. As long as the requirements of the present invention are satisfied, a resin with higher gloss can be obtained by reducing the rubber particle size. The permanent diameter of this rubber particle can be measured using a Coulter counter, and it is preferable that the obtained distribution map has a single and sharp distribution. Alternatively, a bimodal distribution may be used.

In the impact-resistant styrenic resin of the present invention, the gel content (content of toluene-insoluble matter) G is 15 to 40,
Preferably, the swelling index of the gel in the resin is in the range of 7 to 13. Further, the molecular weight of the resin portion is usually in the range of 180,000 to 280,000 in terms of weight average molecular weight. The amount of styrene oligomer remaining in the resin affects the heat control properties, so it is usually less than 1 treble,
Particularly for those requiring heat resistance, it is desirable that the amount is 0.5% or less.

The particular conjugated/ene polymer comb used as a toughening agent in the present invention is typically dissolved in 2-25N suspended styrene to produce a high impact styrenic resin.

Regarding the method for obtaining the impact-resistant styrenic resin of the present invention, there are no particular limitations and known methods can be used as long as consideration is given to satisfying the requirements of the present invention. Alternatively, 1 cup of bulk suspension is advantageously used industrially.

Generally, in bulk polymerization, a specific conjugated diene polymer rubber is dissolved in styrene, and when no catalyst is used, it is usually 95 to 2
Heated polymerization is carried out at a temperature of 00°C, while catalytic polymerization or irradiation polymerization is carried out at a lower temperature than usual, e.g.
The styrene polymerization operation continues at a temperature of 80°C. In this bulk polymerization, if desired, a known internal lubricant such as liquid paraffin may be added in an amount of 1 to 5 parts by weight per 100 parts by weight of the polymer. After completion of polymerization, if unreacted styrene is contained in the resulting polymer, it is desirable to remove this styrene by a known method, such as removing under reduced pressure or using an extrusion device designed for the purpose of removing volatile matter. . Stirring can be performed as necessary during bulk polymerization, but after the conversion rate of styrene to polymer, that is, the polymerization rate has progressed to 30% or more,
It is desirable to stop or moderate agitation.

Excessive agitation can reduce the strength of the resulting polymer. Further, if necessary, polymerization may be carried out in the presence of a small amount of a diluent such as toluene or ethylbenzene, and after the completion of the polymerization, these diluents may be removed by heating together with unreacted styrene.

Bulk suspension polymerization is also useful in producing the high impact styrenic resins of this invention. In this method, first the first half of the reaction is carried out in bulk, and the second half of the reaction is carried out by suspension polymerization. That is, a styrene solution of a specific conjugated diene polymer rubber,
As in the case of bulk polymerization, heat polymerization without catalyst, catalytic mulberry polymerization, or irradiation polymerization is carried out to partially polymerize usually 50% or less of styrene, particularly preferably 10 to 40%. let This is the first half of bulk polymerization. This partially polymerized mixture is then placed in the presence of a suspension stabilizer or a combination thereof with a surfactant.

The mixture is dispersed in an aqueous medium with stirring, and the second half of the reaction is completed by suspension polymerization. The generated polymer is washed,
Dry and grind into pellets or powder if necessary.

In addition to the above methods, useful impact-resistant styrenic resins can also be obtained by conventionally known methods that are modified or improved from these methods. In addition, a portion of the styrene that forms the entire impact-resistant styrenic resin along with certain conjugated/ene polymer rubbers,
A monomer other than styrene that can be radically polymerized with styrene may be substituted. Such monomers account for 50% of all monomers including styrene. It is used in a range of t% or less. Examples of copolymerizable monomers other than styrene include α-methylstyrene, vinyltoluene, vinyletherbenzene, vinylquinrene, and vinylnaphthalene (D
-E: Examples include novinyl aromatic hydrocarbons, conjugated dienes such as butadiene and ingrene, acrylonitrile, and methyl methacrylate. These monomers may be used alone or in combination of 1.2 or more.

Effects of the Invention The impact-resistant styrenic resin of the invention can be used in a wide variety of practically useful products by processing methods such as injection molding and extrusion molding. Furthermore, during processing, other thermoplastic resins such as antioxidants, ultraviolet absorbers, flame retardants, lubricants, mold release agents, fillers, etc., such as general-purpose boristerene, methacrylic resin, polyphenyl ether, etc., may be added as required. It may be used in combination with polycarbonate or the like.

The ItI impact styrenic resin of the present invention has higher rigidity and better rain impact resistance than conventional impact 1'i styrenic resins, so it has a wide range of applications. The industrial significance is extremely significant.

EXAMPLES Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way.

Example 1 A combination of butanene or butadiene and divinylbenzene was used as a monomer, n-butyllithium was used as a catalyst, n-hexane was used as a solvent, and tetrahytron was used as a vinyl modifier in the proportions shown in Table 1. In Run K, a polybutane rubber was obtained using four groups and one arsenic as a camping agent. The divinylbenzene used was commercially available diethylbenzene containing 57% by weight of a mixture of divinylbenzene isomers and the remainder consisting of ethylvinylbenzene and diethylbenzene.

Polymerization of polybutadiene rubber was carried out as follows.

That is, an autoclave with an internal volume of 10 tons and an agitating device and/or burner was thoroughly washed and dried, purged with nitrogen, and then purified and dried butadiene, divinylbenzene, and n-hexane were added, and then n-butyl lithium (5) was added to the autoclave. %n
-Hexane solution was added, and tetrahydrofuran was added as a vinyl regulator, and polymerization was completely initiated at 70°C.

The polymerization temperature rose to 100°C. Thirty minutes after the start of polymerization, silicon tetrachloride was added to the obtained polymer and reacted for 30 minutes. Next, 0.5 phr of 2.6-7-tert-butyl-4-methylphenol (BHT) was added as a stabilizer to the obtained polymer solution, and the solvent was removed by heating to form polybutadiene rubber k? etc.

The custom made polybuta/encom obtained is shown in Table 1.

In addition, the styrene solution viscosity based on the 5-car weight was determined at 25°C using a Cannon-Fenske viscometer (7).

The microstructure was measured using an infrared spectrophotometer (Morello method [La
chimica E T; 1ndustrj, a,
4], 758 (1959)].

Furthermore, the tensile modulus was measured as follows. For example, for the rubber of Example A, 557 rubber was used and 0.034.
Add 0.05, 0.09, 0.15 parts of N, respectively, and use Labo Plast Mill (manufactured by Toyo Seiki) to make 50 to 7
After kneading at 5°C for 2 minutes, the kneaded product was compression molded using a hot press at 160°C for 13, 15 and 17, 20 minutes, respectively, to obtain a peroxide crosslinked notebook with a thickness of 2 mm. Molding time is Asagren 755A (Fushikasei) K
Based on the amount of undecomposed dicumyl peroxide remaining when 1.5 parts by weight of dicumyl peroxide 7 is added per 100M parts of rubber and molded for 30 minutes at 1601c, the following formula is calculated so that this amount is the same. Calculated using

! ! ! 1.5<+) ” = A graph of the relationship between swelling degree and tensile modulus was drawn for various rubbers.The results are shown in Table 2 and the drawings.

As shown in Table 2, the product of rubber swelling degree S and tensile modulus E is almost constant, and any value within the range of about 4 to about 14 can be used as the rubber swelling degree. However, for convenience, the swelling index of the high-impact polystyrene gel obtained using the rubber was taken as the swelling degree of the rubber. That is, the value of Kel's swelling index of the impact-resistant styrenic resin obtained using the Komke of Example A is taken as the value of the degree of swelling of the Komke of Example A, and the relationship between the degree of swelling and the tensile modulus is calculated. The tensile modulus is related to the degree of swelling.

The tensile modulus of the comb of Example A was defined as E. The degree of swelling of other rubbers was determined in the same manner, and the tensile modulus E was determined (Table 1).

Table 2 Next, using the various rubbers shown in Table 1, bulk polymerization was carried out as follows to obtain impact-resistant styrenic resins.

That is, 6 parts by weight of the various rubbers listed in Table 1 and 100 parts by weight of styrene.
Parts by weight, 8N parts of toluene, and 5 parts of BHTo were stirred at room temperature to dissolve various rubbers. This was transferred to a reactor equipped with a stirring device and a jacket, and for each mole of styrene, tert-phthyl peroxide IX was added.
Add 10' mol and incubate at 110°C for 3 hours at 140
Polymerization was carried out at 160°C for 5 hours and 2 hours at 160°C. then 2
After raising the temperature to 30°C and removing unreacted substances under reduced pressure, +BU
0.5 weight parts of T was added per 100 weight parts of the polymer, and the resulting polymer was made into pellets using an extruder. In Comparative Example B, the amount of di-tert-butyl peroxide added and the polymerization temperature were completely controlled to adjust the gel content in the resin.

The properties of each of the pellets thus obtained are shown in Table 3. Each characteristic was determined as follows.

(1) Rubber particle size Measured using a Coulter counter and expressed as a 50% mean diameter.

(2) Content of conjugated diene polymer comb in resin (river [car weight]) Obtained resin (Example A > 1.000 ji 50
Dissolve or swell in 0-dichlorobenzene.

This solution or swelling liquid'z800m/! The polymer is precipitated by dropping it little by little into methanol while stirring. After filtering off this precipitate, 80°C, 3 mrN g
Dry in vacuum dryer 4 for 8 hours, cool and weigh. The N content of the polymer thus obtained was 0.986F.

Add 50ml of 0-dichlorobenzene to 0.50Of of the above purified polymer and dissolve or swell it.

Add 1 ml of a freshly prepared benzene solution of osmium tetroxide and 10 tnl of tert-butyl hydroperoxide to the swelling solution (2), hold this mixture at 1110°C for 10 minutes, After the swelling liquid became transparent, it was cooled in a room temperature cabinet for 1 hour, and then 800ml!
dropwise into methanol to precipitate the polymer. The precipitate was filtered, washed thoroughly with 200 m of methanol, and dried at 80°C and 3'mmHg under reduced pressure.
Dry for an hour, cool and weigh. The polybutane rubber was oxidatively decomposed in this way, and the weight of the polymer remaining after removal was 0.465f. Therefore, R is 6 as shown below.
．． It becomes 9%.

R was determined in the same manner for other resins.

(3) Gel content in resin (toluene insoluble content) G
(i amount %) and swelling index of gel in resin obtained resin (
Example A) Add 201 toluene to 1,001' and boil for 1 hour! Mix, dissolve or swell. Next, the gel is sedimented using a centrifuge, the supernatant is discarded, and the sedimented gel is weighed. The M amount of the swollen gel thus obtained was 2.26 or. Next, this swollen gel was further heated to 3M for 45 minutes at 160°C and normal pressure.
TnH? Dry under reduced pressure for 15 minutes, cool and weigh the wheat. The weight of the gel thus obtained was (1,226
It was good. Therefore, the Kel content in the resin and the swelling index of Kel in the resin are determined as follows.

Similarly, the swelling index (()) and the gel swelling index were determined for the pond resin.

(4) Impact Resistance and Rigidity The resulting resin was subjected to total pressure composition molding, and the Izot impact strength was measured to determine impact resistance and the flexural modulus was measured to determine rigidity according to JIS K 6871.

As is clear from Tables 1 and 3, only those whose η8・E・S value and G/R value are within the range of the present invention are excellent in both Izotsu impact strength and rigidity. I understand.

Example 2 Using the polybutadiene rubber of Example A, all impact-resistant stereoscopic resins having different gel contents as shown in Table 4 were combined. Polymerization of the ml impact-resistant snalene resin was carried out in the same manner as in Example 1, except that the amount of polymerization initiator added and the bundling temperature were controlled. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 4.

Table 4 As is clear from Table 4, the values of η6・E, S and 0/
Those whose R values are both within the range of the present invention are excellent in both isot impact strength and rigidity, but the former is within the range of the present invention, but the latter's G/R value is smaller than the range of the present invention. In Example 112, both the Izot impact strength and rigidity are inferior, and in Example 112, where the G/R value is larger than the range of the present invention, although the rigidity is excellent, the Izot impact strength is inferior. I understand.

[Brief explanation of the drawing]

This is a graph showing an example of the relationship between swelling degree and tensile modulus in a co-diene polymer rubber using the impact-resistant styrene resin (C) of the present invention. Patent applicant: Japan Elastomer Co., Ltd. Agent A-gata Meikan Shiba d 1982 Patent Application No. 10591.7";l'') F+ 8: Impact-resistant styrenic resin using low elastic modulus rubber 3 corrections Relationship with the case considered Patent applicant Address: 1-1-2 Yurakucho, Sen-Daida-ku, Tokyo Representative: Tsutomu Kadoya 4, Agent: Shimitsu Kawa, 2-2-2, Shinbashi, Minato-ku, Tokyo 105 - Houshin Building 8th Floor 8, Contents of amendment (1) “On page 4, line 11 and line 13 of the specification”
Correct "Rubber-like Elastic Body" to "1-Rubber-like Polymer". (2) ``1 rubber-like elastic body'' on the 10th line of the 5th page of the same page is changed to ``
Corrected to "rubber-like polymer". (3) Delete "each" from the 2nd and 3rd lines of page 11. (4) “S■” in the 2nd and 13th lines of page 14
” will be corrected to “η8”. (5) "Organolithium compounds" in line 11 of page 15 will be corrected to "monoorganolithium compounds." (6) On page 18, lines 4 and 5, "by lowering the polymerization temperature" is corrected to "by increasing the polymerization temperature." (7) On page 22, lines 4-3 from the bottom, "polyphenyl ether" and "polyphenylene ether" are corrected. (8) On the bottom line of page 27, correct ``The unit is 2.J'' to ``The unit is parts by weight.''

Claims (1)

[Claims] 1. An impact-resistant styrenic resin obtained by dissolving a conjugated diene polymer rubber obtained by solution polymerization in the presence of an organolithium compound in styrene and polymerizing the solution at a temperature of 25°C. The viscosity of the 5 weight ratio styrene solution of the conjugated diene polymer rubber measured as ηs (cpS), and the tensile modulus of the organic peroxide crosslinked product of the conjugated diene polymer as E(
Kg/cr/i) and swelling degree as S, η
8・E-8≦20000, and the content G of toluene insoluble matter in the resin
and the content R of the conjugated diene copolymer rubber G/R
An impact-resistant styrenic resin using low elastic modulus rubber, which is characterized in that it is in a range of greater than 1.5 and less than 3.5.