JPH02123146A - Production of thermoplastic resin composition and graft copolymer - Google Patents

Abstract

PURPOSE:To obtain a composition excellent in impact, heat, weather resistance, rigidity, etc., by containing a maleimide-based graft copolymer prepared by a specific emulsion polymerization method and having high characteristics and a specified rigid copolymer therein. CONSTITUTION:A composition consisting of (A) 10-60 pts.wt. graft copolymer obtained by using 60-20 pts.wt. mixture consisting of (A2) 5-30wt.% maleimide- based monomer, 25-80wt.% aromatic vinylic monomer, 5-40wt.% vinyl cyanide- based monomer and 0-50wt.% other copolymerizable monomers, continuously adding the component (A2) and a redox-based initiator to a polymerization system for >=1hr in the presence of (A1) 40-80 pts.wt. (solid content) EPDM- containing crosslinked latex containing a modified low-molecular weight alpha- olefinic copolymer in an amount of 0.1-20 pts.wt. based on 100 pts.wt. EPDM and carrying out emulsion polymerization using two or more kinds of emulsifying agents while keeping the pH of the polymerization aqueous phase at 10-7 and (B) 90-40 pts.wt. rigid copolymer consisting of the monomer of the component (A2).

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a thermoplastic resin composition and a graft copolymer, and particularly relates to a method for producing a thermoplastic resin composition and a graft copolymer, and in particular, a thermoplastic resin composition containing a specific graft copolymer and a hard copolymer. A thermoplastic resin composition with excellent impact resistance, heat resistance, rigidity, weather resistance, and falling weight impact strength, and a high-performance graft copolymer suitable as a component of this thermoplastic resin composition in a stable and high yield. The present invention relates to a method for producing a graft copolymer that can be obtained by.

[Conventional technology] Styrenic resins such as ABS (acrylonitrile-styrene-butadiene copolymer) resins have been used more than ever because they have high impact resistance, good dimensional accuracy, and excellent moldability. Although it is widely used as a molding material, it has the disadvantage of poor heat resistance. Therefore, many studies have been conducted to improve the heat resistance of styrene resins such as ABS resins and to further improve their impact resistance.

For example, a maleimide-based graft copolymer obtained by graft-copolymerizing a conjugated diene-based rubbery polymer with a maleimide-based compound and an aromatic vinyl monomer is effective in improving heat resistance and impact resistance. It has been reported that (
Japanese Patent Publication No. 46-34103, Japanese Patent Publication No. 47-6891).

In addition, a method of producing a maleimide-based graft copolymer by imidizing a graft copolymer obtained by grafting maleic anhydride and other vinyl monomers onto a rubber-like polymer with ammonia or a primary amine (especially Kaisho 57-100104.
JP-A-6O-155216) and the rubber-modified maleimide-based graft copolymer obtained by this method, styrene/
A composition blended with a copolymer such as acrylonitrile (JP 58-185642, JP 58101141)
It has been reported to have excellent heat resistance and impact resistance.

Furthermore, for the purpose of improving impact resistance, polymerization was carried out in the presence of a rubbery polymer by regulating the supply rate of imide monomer to the polymerization system within a specific range, thereby making the copolymer composition homogeneous. A method has been proposed (Japanese Unexamined Patent Publication No. 59-11322).

[Problems to be Solved by the Invention] Among the above-mentioned conventional techniques, in the method of graft copolymerizing a maleimide compound and an aromatic vinyl-based IT compound to a conjugated diene-based rubbery polymer, homogeneous It is difficult to carry out graft polymerization, and furthermore, the heat resistance and impact resistance of the resulting resin composition using the maleimide-based graft copolymer are disadvantageous.

In addition, the method of imidizing a graft copolymer obtained by grafting maleic anhydride and other vinyl monomers onto a rubbery polymer with ammonia or a primary amine requires a complicated polymerization process and requires high temperatures. The disadvantage is that it requires a reaction. Moreover, in practice, it is extremely difficult to produce a high rubber maleimide-based graft copolymer having a rubber content of 40% by weight or more because of limitations on polymerization conditions and the like.

Therefore, a composition containing a rubber-modified maleimide-based graft copolymer produced by this method does not have sufficiently satisfactory properties.

Furthermore, a method in which the rate of supply of the maleimide monomer to the polymerization system is controlled within a specific range is industrially disadvantageous because it takes a long time to complete the polymerization.

The present invention solves the above conventional problems, has good weather resistance,
It is an object of the present invention to provide a thermoplastic resin composition that has excellent impact resistance, heat resistance, and rigidity, has high falling weight surface 7 strength, and has an excellent balance of these properties.

The present invention also provides that a maleimide-based graft copolymer suitable for producing a thermoplastic resin composition having such excellent properties can be obtained with high polymerization stability and high yield by an emulsion polymerization method. The purpose of the present invention is to provide a method for producing a graft copolymer that can be produced.

[Means and effects for solving the problem] The thermoplastic resin composition of claim (1) comprises 10 to 60 parts by weight of the maleimide-based graft copolymer of the following (A) and the hard copolymer of the following (B). It is characterized by containing 90 to 40 parts by weight.

(A): Ethylene/propylene/non-conjugated diene copolymer containing 0.1 to 20 parts by weight of a modified low molecular weight α-olefin copolymer per 100 parts by weight of the ethylene/propylene/non-conjugated diene copolymer. Contains crosslinked latex 40~
In the presence of 80 parts by weight (as solid content), 5 to 30% by weight of maleimide monomer, and 25 to 80 parts by weight of aromatic vinyl i-mer.
fi 2%, vinyl cyanide I'It ffi form 5-4
0% by weight and 0 to 0 monomers copolymerizable with these monomers
Maleimide graft copolymer (B) obtained by emulsion graft polymerization of 60 to 20 parts by weight of a monomer mixture containing 50% by weight: 5 to 30% by weight of maleimide monomer, aromatic vinyl monomer The graft copolymer of claim (2) is a hard copolymer containing 25 to 80% by weight, 5 to 40% by weight of a vinyl cyanide monomer, and 0 to 50% by weight of a monomer copolymerizable with these monomers. The method for producing the polymer includes adding 0.1 to 0.1 to 100 parts by weight of a modified low molecular weight α-olefin copolymer to 100 parts by weight of an ethylene/propylene/non-conjugated diene copolymer.
In the presence of 40 to 80 parts by weight (as solid content) of a crosslinked latex containing 20 parts by weight of ethylene/propylene/nonconjugated diene copolymer, 5 to 30 parts by weight of maleimide monomer, and aromatic vinyl monomer. 60 to 20 parts by weight of a monomer mixture containing 25 to 80% by weight of vinyl cyanide monomer, 5 to 40% by weight of vinyl cyanide monomer, and 0 to 50% by weight of a monomer copolymerizable with these monomers. When producing a graft copolymer by emulsion polymerization using two or more emulsifiers, the above 'J, Fc mixture and redox initiator are continuously added to the polymerization system for one hour or more, and From the start of polymerization to the end of polymerization, the pH of the polymerized aqueous phase was adjusted to 1.
It is characterized by adding alkaline water sequentially or continuously to maintain the temperature between 0.0 and 7.0.

That is, the present inventors are weather resistant and impact resistant! After extensive research in order to obtain a thermoplastic resin composition that has a good balance of properties, heat resistance, rigidity, and falling weight impact strength, we have formulated a specific maleimide-based graft copolymer and hard copolymer in specific proportions. The inventors have discovered that a thermoplastic resin composition having extremely poor properties can be obtained by doing so, and have completed the invention of claim (1).

Further, in order to obtain a method for efficiently producing a maleimide-based graft copolymer used in such a high-performance thermoplastic resin composition, the following studies were conducted.

Examples of methods for producing male-imide graft copolymers using maleimide monomers include solution polymerization, bulk polymerization, and suspension polymerization. The emulsion polymerization method is advantageous because the homogeneity of the components can be easily controlled and the 71-neumide graft copolymer can be made into a high rubber.

However, attempts have been made to graft copolymerize aromatic vinyl monomers, vinyl cyanide monomers, maleimide 4i-mers, etc. onto ethylene-propylene-nonconjugated diene copolymers using emulsion polymerization. If all the monomers are added to the polymerization system at once or in a very short period of time to start polymerization, the stability of the latex may deteriorate and copolymerization may become impossible. Even if the polymerization is completed and a 71/imide graft copolymer is obtained, the polymerization yield is low and the graft component is heterogeneous, so such a maleimide graft copolymer cannot be used. Good characteristics cannot be obtained with the resin composition used.

As a result of investigating the reason for this, it was found that when the pH of the polymerization aqueous phase is set to 9 or higher, the maleimide monomer becomes more susceptible to hydrolysis, causing a decrease in p in the polymerization system and reducing the surface activity of the emulsifier. It was found that the stability of latex deteriorates due to the decrease in

In particular, EPI)M (ethylene/propylene/non-conjugated diene copolymer) latex is easily affected by pH and is unstable. Furthermore, it is known that maleimide monomers and aromatic vinyl monomers have high polymerizability and are preferentially polymerized, but their polymerization rate is strongly influenced by the pH of the polymerized aqueous phase. It was found that the composition of the graft component, the graft ratio, the molecular weight of the graft compound, etc. were greatly affected.

Based on this knowledge, we conducted further research on an emulsion polymerization method that has excellent polymerization stability, has a high m unit ratio, and has good properties of the resulting resin composition using the maleimide-based graft copolymer. As a result, it was discovered that by specifying the monomer addition time and the pH of the polymerization water system, a maleimide-based graft copolymer with high polymerization stability and excellent properties could be obtained in high yield, and the following claims were made: The invention of (2) was completed.

The present invention will be explained in detail below.

First, the thermoplastic resin composition of claim (1) will be explained.

The thermoplastic resin composition according to claim (1) contains the maleimide graft copolymer (A) and the hard copolymer (B) in a specific ratio.

In (A), the rubber component ethylene-propylene-non-conjugated diene copolymer (hereinafter abbreviated as rEPDMJ) is a rubber-like copolymer of ethylene, propylene and non-conjugated diene. The weight ratio of ethylene to propylene is preferably in the range of 85:15 to 30:70. In addition, as a non-conjugated diene component,
1.4-hexadiene, 5-ethylidene-2-norbornene, 5-vinylnorbornene, dicyclopentadiene, etc. are preferred.

Examples of the modified low molecular weight α-olefin copolymer include acid-modified polyethylene containing 99.8 to 80% by weight of α-olefin and 0.2 to 20% by weight of an unsaturated carboxylic acid compound. Here, examples of the α-olefin include ethylene, and examples of the unsaturated carboxylic acid compound include acrylic acid, maleic acid, itaconic acid, maleic anhydride, itaconic anhydride, and maleic acid monoamide.

By blending such a modified low molecular weight α-olefin copolymer with 0.1 parts by weight or more to 100 parts by weight of the EPDM, the stability of the obtained EPDM-containing crosslinked latex can be improved, and the impact strength can be improved. However, if the amount exceeds 20 parts by weight, it will cause damage.
This results in a significant decrease in strength. Therefore, in the present invention,
EPDM-containing crosslinked latex contains 0.1 to 2 parts of modified low molecular weight α-olefin copolymer to 100 parts by weight of EPDM.
It is assumed that 0 part by weight is blended.

Monomers to be graft-polymerized to EPDM include maleimide #mer, aromatic vinyl monomer, vinyl cyanide *-
It is a mixture of monomers that can be combined with these monomers if necessary. These-! Among the lIL molecules,
Examples of maleimide monomers include maleimide, N-methylmaleimide, N-ethylmaleimide, N-butylmaleimide, N-laurylmaleimide, N-phenylmaleimide, N-(p-bromophenyl)maleimide, and the like. Examples of aromatic vinyl monomers include styrene, α-
Examples include methylstyrene and p-methylstyrene.

Examples of vinyl cyanide monomers include acrylonitrile,
Examples include methacrylate trile. Furthermore, examples of copolymerizable monomers include methacrylate, methyl methacrylate, and the like.

In the present invention, the monomer mixture includes maleimide monomer 5
~30% by weight, aromatic vinyl monomer 25-80% by weight
, 5 to 40% by weight of a vinyl cyanide monomer, and 0 to 50% by weight of a copolymerizable monomer. In the monomer mixture, the maleimide monomer in particular acts effectively to improve the balance between impact strength and heat resistance of the final resin composition, and if the maleimide J# polymer is less than 5% by weight, the impact strength A resin composition with an excellent balance between heat resistance and heat resistance cannot be obtained. In addition, copolymerization is possible! The I-mer is not necessarily required and may not be used in the present invention.

The maleimide graft copolymer (A) is the EPD
60 to 80 parts by weight (as solid content) of the EPDM-containing crosslinked latex containing 0.1 to 20 parts by weight of a modified low molecular weight α-olefin copolymer to 100 parts by weight of M, and 60 to 80 parts by weight of the above monomer mixture. 20. It is obtained by emulsion graft polymerization of part ii. When the EPDM-containing crosslinked latex of the maleimide-based graft copolymer is less than 40 parts by weight and the A-mer mixture exceeds 60 parts by weight, or when the EPDM-containing crosslinked latex exceeds 80 parts by weight and the monomer mixture is 20 parts by weight. If the amount is less than 1 part by weight, the balance between Ji impact strength and heat resistance of the final resin composition will be significantly deteriorated.

On the other hand, the hard copolymer (B) contains maleimide monomer 5
~30% by weight, aromatic vinyl monomer 25-80% by weight
, 5 to 40% by weight of a vinyl cyanide monomer and, if necessary, 0 to 50% by weight of a monomer copolymerizable with these monomers. As preferable specific examples of each monomer, those listed as specific examples of the 11V-mer in the monomer mixture used in the maleimide-based graft copolymer (A) can be used, and the composition ratio thereof is desirably approximately equal to the composition ratio of the maleimide graft copolymer (A). In the hard copolymer (B), if the maleimide-based 4i-mer is less than 5% by weight, the heat resistance of the final resin composition D will decrease significantly, and if it exceeds 30% by weight, the impact strength will decrease. It is also not preferable.

The thermoplastic resin composition of the present invention comprises 10 to 60 mvc parts of the maleimide graft copolymer (A) mentioned above and (B
), and preferably the total of (A) and (B) is 100 parts. If the maleimide graft copolymer is less than 10 parts by weight and the hard copolymer is more than 90 parts by weight, the impact resistance will be poor; If the combined amount is less than 40 parts by weight, the heat resistance will be poor, and either case is not preferred.

p! of claim (1) of the present invention! 1. The desirable resin composition comprises (A) the maleimide-based graft copolymer and C.
A predetermined amount of the hard copolymer of B) is further mixed with antioxidants, lubricants, processing aids, pigments, fillers, etc. as necessary,
For example, it can be easily produced by kneading and pelletizing using an extruder, Banbury mixer 1 kneading roll, or the like.

The method for producing a graft copolymer according to claim (2) is a method suitable for producing a maleimide-based graft copolymer which is a raw material for producing the thermoplastic resin composition according to claim (1).

The method for producing a graft copolymer according to claim (2) will be explained below.

In order to produce a maleimide-based graft copolymer according to the method of claim (2), it is preferable to produce it as follows, for example.

First, an EPDM-containing crosslinked latex is produced using EPDM and a modified low molecular weight α-olefin copolymer. That is, predetermined amounts of EPDM and modified low molecular weight α-olefin copolymer are dissolved in a suitable solvent, and an emulsifier is added thereto to emulsify. In this case, an aliphatic or alicyclic hydrocarbon solvent such as n-hexane or cyclohexane can be used as the solvent. The emulsifier is not particularly limited, but anionic surfactants such as potassium oleate and disproportionated potassium rosinate can be used. The amount of emulsifier added is preferably 1 to 10 parts by weight based on EPDM. The emulsifier can also be added by, for example, mixing oleic acid with a solution of EPDM and modified low-molecular-weight α-olefin, and adding an aqueous potassium hydroxide solution thereto to generate potassium oleate. The blending amount of the modified low molecular weight α-olefin is 0.1 to 20 parts by weight based on EPDM. ! , by adding a modified low molecular weight α-olefin in a proportion of
It is possible to carry out stable graft copolymerization and to improve the physical properties of the final resin composition.

After a solution of E'PDM and modified low molecular weight α-olefin is emulsified with an emulsifier, this is sufficiently stirred and the solvent is distilled off to obtain a latex having a particle size of 0.2 to 1 μnl W degrees.

Next, 0.1 to 5 ml of a polyfunctional compound such as divinylbenzene is added to 100 mi parts of EPDM in this latex.
．． 0 parts by weight and 0.1 to 5 parts by weight of an organic peroxide such as di-t-butyl-oxytrimethylcyclohexane. A crosslinked latex is prepared by adding Oll to the back side and reacting at 60 to 140°C for about 0.5 to 5.0 hours.

In the present invention, E P D prepared in this way
Gel content of M-containing crosslinked latex is 40-950-9
Preferably, the weight is 5. The gel content of the cross-linked latex is determined by washing the latex with dilute sulfuric acid and drying it.
It can be determined by soaking for a period of time, then filtering through a 200-mesh stainless wire mesh, and drying the remaining residue.

Next, to the crosslinked latex 40 prepared in this way, 80 parts by weight (excluding solid content), 5 to 30 weight % of maleimide monomer, 25 to 80 weight % of aromatic vinyl monomer, 60 to 20 parts by weight of a monomer mixture consisting of 5 to 40% by weight of a vinyl cyanide monomer and, if necessary, 0 to 50% by weight of a monomer copolymerizable with these monomers, Graft polymerization is carried out by using more than one type of emulsifier and heating to an appropriate polymerization temperature. Examples of emulsifiers used here include anionic surfactant +1 agents such as potassium oleate, disproportionated potassium rosinate, alkali metal salts of furkylbenzenesulfonate, alkali metal salts of alkylnaphthalenesulfonate, and alkali metal salts of lauryl sulfate. It is preferable to select from.

In the present invention, when performing graft polymerization in this way, a redox initiator is mixed with the monomer mixture and added continuously into the polymerization system over an hour or more, and from the start to the end of the polymerization. , the pH of the polymerized aqueous phase was 10.
The pH within the polymerization system is controlled by sequentially or continuously adding an alkaline aqueous solution to maintain the pH within the range of 0 to 7.0.

In the present invention, it is necessary to maintain the pH of the polymerized aqueous phase at 1010 to 7.0, and in particular, from 10 minutes after the start of polymerization until the end of polymerization, p)l should be kept at 9.0. It is preferable to keep it between 0 and 8.0.

As mentioned above, maleimide monomers are susceptible to hydrolysis in aqueous solutions with a pH of 9.0 or higher, but in practice, in the above method, hydration of maleimide f, If, and Decomposition is negligible.

Note that the pH of the polymerized water phase at the start of polymerization is io, o ~ 9.0.
It is preferable from the viewpoint of latex stability that If the pH of the polymerized aqueous phase is less than 7.0, the latex stability deteriorates significantly by -C.

Further, in the present invention, it is necessary to mix one redox initiator with the monomer mixture and continuously add one redox initiator to the polymerization system over one hour or more. When this 41 addition time is less than 1 hour, the latex stability deteriorates and the polymerization yield decreases.

It should be noted that the dox-based initiator used here is preferably an oil-soluble organic peroxide, and is usually used in combination with one kilogram of ferrous sulfate, one agent, and one reducing agent. Ru.

The oil-soluble initiator is preferably an organic peroxide such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, or tert-butyl hydroperoxide. As the chelating agent, sodium pyrophosphate, sodium ethylenediaminetetraacetate, etc. are preferred.

As the title agent, formaldehyde sulfoquinole-1 sodium chloride, dextrose, sodium ascorbate and the like are preferred.

An antioxidant is added to the maleimide-based graft copolymer dex obtained by completing the polymerization, if necessary.

Next, a resin solid is precipitated from the obtained maleimide graft polymer latex. In this case, as a precipitating agent, for example, an aqueous solution of sulfuric acid, acetic acid, calcium chloride, magnesium sulfate, etc. may be used alone or in combination. The maleimide-based kraft copolymer latex to which a precipitating agent has been added is heated and stirred, and then the precipitate is separated, washed with water, dehydrated, and dried.71.
(B) used in claim (1) of the present invention
The method for producing the hard copolymer will be explained.

For producing the hard copolymer (B), polymerization methods such as emulsion polymerization and suspension polymerization are employed.

When the hard copolymer is synthesized by emulsion polymerization, common emulsifiers for emulsion polymerization such as potassium rosinate and sodium alkylbenzenesulfonate can be used as the emulsifier. Further, as the polymerization initiator, an organic or inorganic peroxide type initiator is used, and as the iI chain transfer agent, mercaptans, α-methylstyrene dimer, terpenes, etc. are used.

When synthesizing a hard copolymer by suspension polymerization, as a suspending agent,! - Licalcium phosphite, polyvinyl alcohol, etc. are used, and sodium alkylbenzenesulfonate etc. can be used as a suspension aid. Further, as the initiator, organic peroxides are used, and as the chain transfer agent, mercaptans, α-methylstyrene, terpenes, etc. can be used.

To synthesize a hard copolymer, monomers constituting the copolymer are mixed in predetermined amounts, and a suitable emulsifier or suspending agent, initiator, and chain transfer agent are added and polymerized. Next, in the case of hard resin latex obtained by emulsion polymerization, resin solids are precipitated. In this case, as the precipitating agent, for example, an aqueous solution of sulfuric acid, acetic acid, calcium chloride, magnesium sulfate, etc. can be used alone or in combination. The precipitate is washed with water, dehydrated, and dried as necessary to obtain a hard copolymer.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Production Examples, Examples, and Comparative Examples, but the present invention is not limited to the following Examples unless it exceeds the gist thereof. In addition, in the following, "parts" indicate "parts by weight."

Production Example I Production of EPDM-containing cross-linked latex EPDM (EPT3045) 100 manufactured by Mitsui Petrochemicals
After dissolving 1 part in 566 parts of n-hexane, acid-modified polyethylene (Hiwax 2203A) manufactured by Mitsui Petrochemicals Co., Ltd. was added in amounts shown in Table 1, and oleic acid was further added to completely dissolve. Separately, an aqueous solution prepared by dissolving 9 parts of KOHo in 180 parts of water was kept at 60° C., and the prepared polymer solution was gradually added thereto to emulsify it, followed by stirring with a homomixer. Next, the solvent is distilled off to reduce the particle size to 0.2 to 1 μm.
of latex was obtained.

To this latex, 1.5 parts of divinylbenzene and 1.0 parts of di-t-butylperoxytrimethylcyclohexane were added to 100 parts of EPDM, which is a rubber component, and reacted at 120°C for 1 hour to create an EPDM-containing cross-linked Radess Nos. 1-1 to 1-4 were prepared.

In addition, each EPDM-containing crosslinked latex was coagulated with dilute sulfuric acid, washed with water and dried, and then 1 g of this was collected and
00 mu toluene for 40 hours, then 20 mu
The gel content of each latex was determined by filtering through a stainless wire mesh with 0 mesh and drying the residue, and the results shown in Table 1 were obtained.

Table 1 Production Example 2 Production of Graft Copolymer In a stainless steel polymerization tank equipped with a stirrer, No. 2-1 in Table 2 was placed.
The raw materials were prepared according to the recipe shown in ~2-16 and polymerization was carried out. The polymerization temperature was kept constant at 80°C.

In addition, the addition time of the ingredient (!■) is 150 minutes, the addition time of the ingredient (Ill
) was added for 180 minutes. However, No, 2-
Regarding No. 13, the addition time of component (11) was 30 minutes, and the addition time of component (III) was 60 minutes. Further, the pH of the polymerized aqueous phase was as shown in Table 2.

After polymerization, an antioxidant is added, solid content is precipitated with sulfuric acid, and through the steps of washing, dehydration, and drying, maleimide graft copolymer powders 2-1 to 2-5.2-8 to 2-1
5 and maleimide-free graft copolymer 2-1
I got 6.

In addition, graft copolymers No. 2-1 to 2-5 and No.
, 2-7 to 2-16 are shown in Table 2. The monomer conversion rate was calculated from the amount of residual monomer obtained by collecting a portion of the latex and using gas chromatography.

As is clear from Table 2, No. 2-6, in which the pH of the polymerized aqueous phase was 7.0 or less, solidified in 95 minutes after the start of m-merization.
In addition, No. 2-7, in which the pH of the polymerized water phase exceeded 10.0,
Monomer conversion was low. Furthermore, No. 2-1 in which the mixture of monomer and initiator was added into the polymerization system in less than 1 hour.
3 also had a low monomer conversion rate.

Production Example 3 Production of Hard Copolymer After the interior of an autoclave equipped with a stirrer was sufficiently purged with nitrogen, as shown in Table 3, the following ingredients were added: distilled water, a surfactant, a suspension stabilizer, An organic peroxide was charged, and the internal temperature was raised to 80° C. while stirring at a rate of 350 rpm, and polymerization was carried out at this temperature for 9 hours. Next, the temperature of the indoor bath was raised to 120° C. over 2.5 hours, and the reaction was carried out at this temperature for 2 hours. The resulting slurry was washed, dried and
Hard copolymers Nos. 3-1 to 3-6 were obtained.

Examples 1-8. Comparative Examples 1 to 8 The graft copolymer obtained in Production Example 2 and the hard copolymer obtained in Production Example 3 were mixed with 0.5 parts by weight of calcium stearate and 1 part of N,N'-ethylenebisstearylamide.
．． The composition shown in Table 4 together with 5 parts by weight was kneaded in a Banbury mixer and molded at 260°C.

The properties of the obtained molded products No. 4-1 to 4-15 were tested under the following conditions and method.

Izod impact value (kg-am/cm) = ASTM (
D256) Notched isot, measurement temperature 23℃ Heat distortion temperature (℃) = ASTM (064B-56) Tensile strength (kg/am2) = ASTM (D838) 1/8" Measurement temperature 23℃ Falling weight impact value (kg- cm) = Shimadzu Hydroshot HTM-1 was used under the following conditions: perseverance speed + 5.0 m/sec prologue: 1/4" R sample holder = l゛φ measurement temperature: 23°C.

Moreover, the weather resistance of the molded bodies of Examples 1 to 8 (No. 4-1 to 4-3 and No. 4-f3 to 4-10) was examined by the following method.

The weather resistance test pieces were tested using a weather meter (Suga Test Instruments Sunshine Super Long Life Izod impact value after 400 hours (according to ASTM D 256).

-30°C, no notch) and evaluated based on this impact value.

For comparison, general-purpose ABS resin (rubber content 20% by weight)
The weather resistance was also investigated in the same manner (Comparative Example 8).

The results are shown in Table 4.

From Table 4, the thermoplastic resin composition of the present invention has impact resistance, heat resistance, rigidity, weather resistance, and drop resistance of 8i! ! It is clear that the impact strength and other properties are well balanced and have extremely excellent properties.

Table (Part 1) [Effects of the Invention] As detailed above, according to the thermoplastic resin composition of claim (1), WA impact resistance, heat resistance, rigidity, weather resistance, falling weight impact strength, etc. An extremely excellent high-performance thermoplastic resin composition having extremely high properties and a good balance of these properties is provided.

Further, according to the method for producing a graft copolymer of claim (2), a maleimide-based graft copolymer (having poor properties) is suitable for producing the high-performance thermoplastic resin composition of claim (1). It is possible to produce a polymer in high yield with high polymerization stability.

Agent: Patent attorney Tsuyoshi Shigeno

Claims (2)

[Claims] (1) Maleimide-based graft copolymer 10 shown below (A)
~60 parts by weight and 90 to 40 parts by weight of the following hard copolymer (B)
A thermoplastic resin composition comprising parts by weight. (A): Ethylene/propylene/non-conjugated diene copolymer containing 0.1 to 20 parts by weight of a modified low molecular weight α-olefin copolymer per 100 parts by weight of the ethylene/propylene/non-conjugated diene copolymer. Contains crosslinked latex 40~
In the presence of 80 parts by weight (as solid content), 5 to 30% by weight of maleimide monomer, and 25 to 80% by weight of aromatic vinyl monomer.
Emulsion graft polymerization of 60 to 20 parts by weight of a monomer mixture containing 5 to 40 weight % of a vinyl cyanide monomer and 0 to 50 weight % of a monomer copolymerizable with these monomers. Maleimide graft copolymer (B) obtained by: 5 to 30% by weight of maleimide monomer, 25 to 80% by weight of aromatic vinyl monomer, 5 to 40% by weight of vinyl cyanide monomer, and A hard copolymer containing 0 to 50% by weight of a monomer copolymerizable with these monomers (2) Ethylene/propylene/nonconjugated diene copolymer 1
Ethylene/propylene/nonconjugated diene copolymer-containing crosslinked latex containing 0.1 to 20 parts by weight of a modified low molecular weight α-olefin copolymer based on 0.00 parts by weight
In the presence of 0 parts by weight (as solid content), 5 to 30% by weight of maleimide monomer, and 2.5 to 80% by weight of aromatic vinyl monomer.
60 to 20 parts by weight of a monomer mixture containing 5 to 40 weight % of a vinyl cyanide monomer and 0 to 50 weight % of a monomer copolymerizable with these monomers, When producing a graft copolymer by emulsion polymerization using an emulsifier, the above monomer mixture and redox initiator are continuously added to the polymerization system for 1 hour or more, and from the start of polymerization to the end of polymerization. A method for producing a graft copolymer, which comprises adding an alkaline aqueous solution sequentially or continuously to maintain the pH of the polymerized aqueous phase at 10.0 to 7.0.