JPH0657090A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the thermoplastic resin composition excellent in moldability, capable of giving, through injection molding process, molded products of excellent antistaticity, heat resistance and rigidity. CONSTITUTION:The resin composition comprising (A) 10-60wt.% of a graft copolymer, (B) 0-70wt.% of a copolymer from vinyl monomers, (C) 5-50wt.% of an imidated copolymer, and (D) 5-40wt.% of a polyether-esteramide.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermoplastic resin composition which is excellent in permanent antistatic property, moldability, heat resistance and rigidity.

[0002]

2. Description of the Related Art Generally, a styrene resin represented by ABS resin is widely used in electric and electronic equipment parts and OA equipment, and various characteristics such as impact resistance and moldability are required. On the other hand, the styrene-based resin has a high electric resistivity value, so that it has a defect that dust adhesion and electrostatic damage due to electrified electricity occur in electronic devices. Therefore, as these antistatic methods, a method of kneading an antistatic agent, carbon black and metal powder is generally known.

The method of kneading an antistatic agent into a resin is effective as a method of imparting an antistatic property, but has a drawback that the performance is not sufficient and the antistatic effect is not permanent. On the other hand, the method of kneading carbon black or metal powder can give sufficient antistatic property, but
It has a drawback that appearance, molding processability, impact resistance, etc. are deteriorated.

As a method of imparting a permanent antistatic property to a resin, a method of mixing a polyether ester amide elastomer with a thermoplastic resin is known.
However, since the elastomer has poor compatibility with the resin, strength reduction and layered peeling occur, so it is necessary to add a compatibilizer. JP-A-62-241945 discloses a thermoplastic composition comprising a polyether ester amide, an ABS graft copolymer and a carboxyl group-containing modified vinyl polymer. However, this thermoplastic resin composition has the drawbacks of insufficient fluidity, heat resistance and rigidity.

[0005]

[Problems to be Solved by the Invention]
The object of the present invention is to improve the resin composition without sacrificing the properties of the styrene resin, and thus the antistatic property, moldability, and
It is an object of the present invention to provide a thermoplastic resin composition which has heat resistance and rigidity and is excellent in permanent antistatic property without delamination.

[0006]

Means for Solving the Problems As a result of intensive studies conducted by the present inventor for this purpose, a resin composition obtained from a vinyl-based graft copolymer having a specific composition ratio and a vinyl-based copolymer having a specific composition ratio. It was also found that the thermoplastic resin composition for the above purpose can be obtained by blending a polyether ester amide into a resin composition composed of an imidized copolymer containing a specific acid anhydride acid group.

That is, in the present invention, in the presence of (Component A) 10 to 60 parts by weight of a diene rubber polymer, 50 to 90% by weight of an aromatic vinyl monomer and 10 to 50% by weight of a vinyl cyanide monomer. And a monomer mixture consisting of 0 to 20% by weight of a vinyl monomer copolymerizable with these as required.
Graft copolymer obtained by graft polymerization of 40 to 90 parts by weight 10 to 60% by weight (Component B) 50 to 90% by weight of aromatic vinyl monomer, 10 to 40% by weight of vinyl cyanide monomer, and A copolymer obtained by copolymerizing 0 to 20% by weight of a vinyl monomer copolymerizable with these, if necessary, 0 to 70% by weight (C component) 30 to 70% by weight of an aromatic vinyl monomer, Imidized copolymer consisting of 30 to 50% by weight of unsaturated dicarboxylic acid imide derivative, 2 to 15% by weight of unsaturated dicarboxylic acid anhydride monomer and 0 to 20% by weight of other vinyl monomer 5 to 50% by weight (D component) Polyether ester amide 5 to 40% by weight of (A) component, (B) component, (C) component and (D) component is contained, which is excellent in permanent antistatic property. It is a thermoplastic resin composition.

The present invention will be described in detail below. Graft copolymer (hereinafter referred to as A component) The diene rubber polymer used in the A component can be a homopolymer or copolymer of a conjugated diene monomer, or a conjugated diene monomer and other copolymerizable It is a copolymer of various monomers.

The conjugated diene monomer described here includes butadiene, isoprene, dimethylbutadiene, chloroprene and the like.

Other copolymerizable monomers include styrene,
Aromatic vinyl monomers such as α-methylstyrene and vinyltoluene, vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, and (meth) acrylic acid such as methacrylate, ethacrylate, butyl acrylate, methyl methacrylate and ethyl methacrylate. Ester monomers and the like.

As the diene rubber polymer used in the present invention, a copolymer obtained by copolymerizing a polyfunctional vinyl monomer as a crosslinking monomer can also be used.

As the polyfunctional vinyl monomer that can be used,
Examples include divinylbenzene, ethylene glycol dimethacrylate, triallyl cyanurate, allyl acrylate and vinyl acrylate.

As a method for producing the graft copolymer of the component A, a known graft polymerization method can be used. In the presence of the rubber polymer latex, a vinyl cyanide monomer and an aromatic vinyl monomer, Alternatively, it can be obtained by further adding a monomer copolymerizable with these monomers to these monomers and copolymerizing them.

Examples of the vinyl cyanide monomer used as the component A include acrylonitrile and methacrylonitrile.

Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, dimethylstyrene and chlorostyrene.

The above monomers can be used alone or in admixture of two or more.

Examples of the monomer copolymerizable with these monomer components include acrylic acid ester, methacrylic acid ester, acrylic acid, methacrylic acid, acrylic acid amide and methacrylic acid amide.

The graft copolymerization is preferably emulsion polymerization,
Examples of emulsifiers used in emulsion polymerization include fatty acid soaps such as sodium stearate and potassium oleate, and organic sulfonic acids such as disproportionated potassium rosinate and sodium dodecylbenzenesulfonate.

Examples of the method for adding the monomer mixture for graft polymerization include batch addition, partial addition, and continuous division addition of all graft polymerization monomers.

In order to effectively carry out the graft copolymerization,
Continuous divided addition is preferred. The polymerization temperature is preferably in the range of 40 to 90 ° C.

The polymerization initiator is preferably a redox system in which a polyfunctional radical initiator and a metal salt such as ferrous sulfate, a chelating agent such as pyrophosphoric acid or ethylenediaminetetraacetic acid disodium salt are used in combination.

The amount of the initiator used may be 0.05 to 1.0 part by weight based on 100 parts by weight of the polymerizable monomer.

The amount of the diene rubber polymer contained in the component A is 10 to 60 parts by weight. If it is less than 10 parts by weight, impact strength is low, and if it exceeds 60 parts by weight, moldability and rigidity are unfavorably reduced.

The aromatic vinyl monomer is 50 to 90% of all monomers.
If it is less than 50% by weight, the moldability and dimensional stability characteristic of the aromatic vinyl compound are impaired.

The vinyl cyanide monomer is 10 to 10% of all monomers.
50% by weight, if less than 10% by weight, heat resistance is low, 50
If it exceeds the weight%, the moldability is deteriorated.

The component A is 10 to 60% by weight, preferably 10 to 60% by weight based on the total amount of the thermoplastic resin composition of the components A to D.
It is 50% by weight, and if it is less than 10% by weight, impact strength is lowered, and if it exceeds 60% by weight, rigidity and heat resistance are lowered, which is not preferable.

Copolymer (hereinafter referred to as Component B) Examples of the aromatic vinyl monomer used as Component B include styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylvinyltoluene. ,
Examples thereof include dimethylstyrene, chlorostyrene, vinylnaphthalene and the like.

As the vinyl cyanide monomer, for example,
Examples thereof include acrylonitrile and methacrylonitrile.

Examples of the monomer copolymerizable with these monomer components include acrylic acid ester monomers, methacrylic acid ester monomers, vinylcarboxylic acid monomers such as acrylic acid and methacrylic acid, and acrylic acid. Examples thereof include amide and methacrylic acid amide.

The aromatic vinyl monomer is 50 to 90% by weight in the monomers used as the component B. If it is less than 50% by weight, the moldability and dimensional stability characteristic of the aromatic vinyl compound are impaired. .

Of the monomers used as the component B, the vinyl cyanide monomer is 10 to 40% by weight. If it is less than 10% by weight, the heat resistance is low, and if it exceeds 40% by weight, the moldability is deteriorated. .

The component B is 0 to 70% by weight, preferably 0 to 70% by weight based on the total amount of the thermoplastic resin composition of the components A to D.
It is 55% by weight, and if it exceeds 70% by weight, impact strength is lowered, which is not preferable.

In order to obtain a molded product using the thermoplastic resin composition of the present invention, it is necessary to mix the above-mentioned components A and B in a desired ratio. As a mixing method, a known method can be applied to mix both components in an emulsified state, a particle state or a molten state, and melt-kneaded to easily obtain a thermoplastic resin composition.

Imidized Copolymer (hereinafter referred to as C Component) The C component of the imidized copolymer is an aromatic vinyl monomer, an unsaturated dicarboxylic acid imide derivative, an unsaturated dicarboxylic acid anhydride monomer, and It is composed of a copolymerizable vinyl monomer.

As the aromatic vinyl monomer, styrene,
Examples thereof include α-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylvinyltoluene, dimethylstyrene, chlorostyrene and vinylnaphthalene, and among these, styrene is particularly preferable.

The unsaturated dicarboxylic acid imide derivative is obtained by copolymerizing an unsaturated dicarboxylic acid anhydride monomer with an aromatic vinyl monomer and then reacting it with ammonia and / or a primary amine to give an imidized derivative. Or maleimide,
Maleimide monomers such as N-methylmaleimide, N-ethylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide and N-naphthylmaleimide were directly copolymerized with aromatic vinyl monomers and unsaturated dicarboxylic acid anhydrides. It may be one. However, as a method of producing these imidized copolymers, the former, that is, a method of imidizing after copolymerizing an unsaturated dicarboxylic acid anhydride monomer with an aromatic vinyl monomer is a copolymerizable and It is more preferable in terms of economy.

Examples of unsaturated dicarboxylic acid anhydride monomers include anhydrides such as maleic acid, itaconic acid, citraconic acid and aconitic acid. Of these, maleic anhydride is particularly preferred.

The vinyl monomer copolymerizable therewith constitutes a vinyl monomer other than the aromatic vinyl monomer, the unsaturated dicarboxylic acid imide derivative and the unsaturated dicarboxylic acid anhydride monomer. Examples thereof include vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, acrylic acid ester monomers such as methyl acrylic acid ester and ethyl acrylic acid ester, and methacrylic acid esters such as methyl methacrylic acid ester and ethyl methacrylic acid ester. There are monomers, vinylcarboxylic acid monomers such as acrylic acid and methacrylic acid, and acrylic acid amides and methacrylic acid amides, among which acrylonitrile, methacrylic acid esters, monomers such as acrylic acid and methacrylic acid. Is preferred.

Ammonia and primary amines used in the imidization reaction may be in an anhydrous or aqueous state, and examples of primary amines include methylamine, ethylamine, butylamine and cyclohexylamine. And the aromatic amines such as aniline, tolylamine and naphthylamine, of which aniline is particularly preferred.

When the imidization reaction is carried out in a solution state or a suspension state, it is preferable to use an ordinary reaction vessel, for example, an autoclave, and when it is carried out in a bulk molten state,
An extruder equipped with a devolatilizer may be used. A catalyst may be present when the copolymer is imidized, and for example, a tertiary amine or the like is preferably used.

The temperature of the imidization reaction is about 80 to 350 ° C, preferably 100 to 300 ° C. When the temperature is lower than 80 ° C, the reaction rate is slow and the reaction takes a long time, which is not practical.
On the other hand, when the temperature exceeds 350 ° C, the physical properties are deteriorated due to thermal decomposition of the polymer.

Component C is 30 to 70% by weight of aromatic vinyl monomer, preferably 40 to 65% by weight, 30 to 50% by weight of unsaturated dicarboxylic acid imide derivative, preferably 35 to 45% by weight, unsaturated dicarboxylic acid. It is an imidized copolymer composed of 2 to 15% by weight of an acid anhydride monomer and 0 to 20% by weight of a vinyl monomer other than these.

When the amount of the aromatic vinyl monomer is less than 30% by weight, the moldability and dimensional stability characteristic of the aromatic vinyl compound are impaired, and when it exceeds 70% by weight, the heat resistance is lowered.

The amount of unsaturated dicarboxylic acid imide derivative is 30
If it is less than wt%, heat resistance and chemical resistance are not sufficient.
On the other hand, when it exceeds 50% by weight, the copolymer becomes brittle and the moldability is remarkably lowered.

On the other hand, if the amount of the unsaturated dicarboxylic acid anhydride monomer is less than 2% by weight, the compatibility with the polyether ester amide as the component D is not sufficient, which causes delamination of the molded product. Appearance is impaired and impact resistance is also reduced. On the other hand, if it exceeds 15% by weight, the thermal stability decreases.

Polyether ester amide (hereinafter referred to as D component) The D component is a block copolymer having polyether as a soft segment and polyester amide as a hard segment, and can be produced by a known method. The hard segment, which is the polyesteramide moiety of component D, has 6 carbon atoms.
It is composed of the above aminocarboxylic acid, lactam, diamine having 6 or more carbon atoms and a salt of carboxylic acid.

Specific examples of the aminocarboxylic acid include ω-aminocaproic acid, ω-aminoenanthic acid, ω-aminocaproic acid, ω-aminocaprylic acid, ω-aminopergonic acid and 1,1-aminoundecanoic acid. Examples of the lactam include caprolactam, enantolactam, laurolactam and the like. Further, as the dicarboxylic acid salt of diamine, hexamethylenediamine-
Adipate, hexamethylenediamine-sebacate, hexamethylenediamine-isophthalate and the like are used.

The soft segment, which is a polyether moiety, is, for example, polyethylene glycol, poly (1,
2-propylene oxide) glycol, poly (1,3-
Propylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol and the like are used. Among these, polyethylene glycol is particularly excellent in the antistatic effect.

Further, as the dicarboxylic acid component which is a constituent of the component D, for example, a dicarboxylic acid having 4 to 20 carbon atoms is preferable, and terephthalic acid, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid and naphthalene-
Aromatic dicarboxylic acids such as 2,7-dicarboxylic acid, 1,4
Examples thereof include alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid and 1,2-cyclohexanedicarboxylic acid, and aliphatic dicarboxylic acids such as succinic acid, oxalic acid, adipic acid and sebacic acid.

The amount of the component D polyether ester amide is
If it is less than 5% by weight, the antistatic property is not sufficient, and if it exceeds 40% by weight, moldability and rigidity are deteriorated, which is not preferable.

The thermoplastic resin composition of the present invention comprises a vinyl-based graft copolymer (A) component and a vinyl-based copolymer (B).
Component and acid anhydride acid group-containing imidized copolymer (C)
It can be obtained by melting, kneading and extruding a dry blend obtained by mixing the components and the polyether ester amide (D) component with a known mixer such as a tumbler or a Henschel mixer.

If desired, the thermoplastic resin composition of the present invention may further contain stabilizers, plasticizers, lubricants, colorants and the like.

[0053]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited by these examples as long as the gist thereof is not exceeded. In the following, "%" and "parts" are based on weight unless otherwise specified.

Examples 1 to 9 Comparative Examples 1 to 5 Preparation of Component A Graft Copolymer Polybutadiene latex (solid content 30
%, Weight average particle diameter 0.35 μm) 333 parts were charged, and then 234 parts of pure water, 0.005 parts of ferrous sulfate, 0.01 parts of ethylenediaminetetraacetic acid disodium and 0.3 parts of sodium aldehyde sulfoxylate were added, and the mixture was placed under a nitrogen atmosphere. The stirred contents were kept at 50 ° C., and a monomer mixture consisting of 25 parts of acrylonitrile, 75 parts of styrene, 0.6 parts of t-dodecyl mercaptan and 0.2 part of benzoyl peroxide was continuously added to the above latex over 5 hours. After the addition of the monomer mixture was completed, 0.1 part of benzoyl peroxide was added.
Polymerization was completed by stirring at ℃ for 2 hours.

The latex obtained is octadecyl-3.
After adding 1.0 part of-(3,5-di-t-butyl-4-hydroxyphenyl) propionate (manufactured by Ciba Geigy, trade name; Irganox 1076), an aqueous solution containing 8 parts of calcium chloride was added to 95 ° C. The mixture was stirred for 3 minutes to break the emulsion and obtain a slurry. The slurry was dehydrated, washed with water, and dried to obtain a graft copolymer (component A).

Preparation of Component B Copolymer 100 parts of pure water, 2.5 parts of 0.2% potassium persulfate aqueous solution, 0.07 parts of tribasic calcium phosphate and 30 parts of styrene were put into an autoclave.
Part, acrylonitrile 25 parts, t-dodecyl mercaptan
0.6 parts and 0.1 part of benzoyl peroxide were added, and the contents were stirred under a nitrogen atmosphere, and the contents were kept at 100 ° C.
45 parts were continuously added over 2 hours at 100 ° C, 2 hours at 103 ° C and 3 hours at 107 ° C over a total of 7 hours.

After the completion of the addition, the temperature was raised to 117 ° C. and the mixture was stirred for 2 hours to complete the polymerization. After cooling, hydrochloric acid was added to the polymerization solution to neutralize, dehydrate and dry the beads of the copolymer (component B). Got

Manufacture of Component C Imidized Copolymer 100 parts of styrene were charged into an autoclave equipped with a stirrer, the system was replaced with nitrogen gas, and then the temperature was raised to 80 ° C. A solution of 67 parts of maleic anhydride and 0.2 part of benzoyl peroxide dissolved in 300 parts of methyl ethyl ketone was continuously added thereto over 8 hours. After addition, at 80 ℃ 4
After stirring for a time, a styrene-maleic anhydride copolymer was obtained. To this, 52 parts of aniline was added and reacted at 130 ° C for 7 hours. The reaction solution was cooled to room temperature, poured into 300 parts of vigorously stirred methanol, and the precipitated polymer was separated by filtration and dried to obtain an imidized copolymer (C-1).

The amount of aniline added was 58 parts, 45 parts, 30 parts and
Reactions were carried out in the same manner as in (C-1) except that the amount was changed to 64 parts (C-2), (C-3), (C-4) and (C-5).
Got

The composition of the imidized copolymer was determined by ¹³ C-NMR.
Was quantified by Here, St is a styrene group, PMI
Represents an N-phenylmaleimide group, and MAH represents a maleic anhydride group. (C-1) St: 49.0 wt% PMI: 45.2 wt% MAH: 5.8 wt% (C-2) St: 47.7 wt% PMI: 50.0 wt% MAH: 2.3 % By weight (C-3) St: 50.3% by weight PMI: 40.1% by weight MAH: 9.6% by weight (C-4) St: 52.4% by weight PMI: 29.1% by weight MAH: 18 0.5 wt% (C-5) St: 46.9 wt% PMI: 53.1 wt%

Preparation of Component D Polyetheresteramide Polyetheresteramide is 50 parts of caprolactam,
It was obtained from 45 parts of polyethylene glycol with a number average molecular weight of 1000 and 7 parts of adipic acid.

The component A graft copolymer, the component B copolymer, the component C imidized copolymer and the component D polyether ester amide obtained by the above-mentioned method were prepared according to the formulation shown in Tables 1 and 2. 40 after mixing in a mixer
Pellets were prepared by melting and kneading at 230 ° C using an mm extruder. The obtained pellets were used to evaluate Table 1 and Table 2.

[0063]

[Table 1]

[0064]

[Table 2]

The physical properties were measured by the following methods. (1) Izod Impact Strength Using an injection molding machine (IS-80CNV) manufactured by Toshiba Machine Co., Ltd., sample pellets were molded at 220 ° C to prepare test pieces. About this test piece, ASTM D-
The Izod impact strength was measured according to 256.

(2) Flexural modulus Using an injection molding machine (IS-80CNV) manufactured by Toshiba Machine Co., Ltd., the sample pellets were molded at 220 ° C. to prepare test pieces. About this test piece, ASTM D-
The flexural modulus was measured according to 790.

(3) Melt Flow Rate (MFR) The melt flow rate was measured using sample pellets according to JIS K-6874.

(4) Surface specific resistance Using an injection molding machine (IS-80CNV) manufactured by Toshiba Machine Co., Ltd., sample pellets were molded at 220 ° C. and 2 mmt × 100 mm.
A disk of Φ was produced. Room temperature 23 ℃, humidity using this disk
After molding in a 50% RH atmosphere for 24 hours, the surface resistivity was measured using a super insulation resistance meter manufactured by Toa Denpa Kogyo KK.

(5) Heat distortion temperature (HDT) Using the test piece used for measuring the flexural modulus, A
The heat distortion temperature was measured according to STM D-648.

(6) Appearance Using an injection molding machine (IS-80CNV) manufactured by Toshiba Machine Co., Ltd., sample pellets were molded at 220 ° C. and 2 mm × 50 m
A square plate of m × 90 mm was molded. The presence or absence of delamination was visually determined by bending this square plate and observing the fracture surface. ○: Good ×: Delamination occurred in the molded product

[0071]

INDUSTRIAL APPLICABILITY As described above, the thermoplastic resin composition of the present invention is a resin composition having excellent mechanical strength, heat resistance, rigidity and moldability, and also having a permanent antistatic property, which is used in electronic equipment parts. Also, it has a feature that it can be widely used as a molding material in fields such as OA equipment.

Claims (1)

[Claims] 1. A component: 50 to 90% by weight of an aromatic vinyl monomer, 10 to 50% by weight of a vinyl cyanide monomer and, if necessary, 10 to 60 parts by weight of a diene rubber polymer. Graft copolymer obtained by graft polymerization of 40 to 90 parts by weight of a monomer mixture consisting of 0 to 20% by weight of a vinyl monomer copolymerizable therewith (component B) aroma Copolymerization weight of 50 to 90% by weight of group vinyl monomer, 10 to 40% by weight of vinyl cyanide monomer, and 0 to 20% by weight of vinyl monomer copolymerizable with them. Combined 0 to 70% by weight (C component) 30 to 70% by weight of aromatic vinyl monomer, 30 to 50% by weight of unsaturated dicarboxylic acid imide derivative, 2 to 15% by weight of unsaturated dicarboxylic acid anhydride monomer and others Imidized copolymer consisting of 0 to 20% by weight of vinyl monomer 5 to 50% by weight (Component D) Polyether ester amide A thermoplastic resin composition comprising 5 to 40% by weight of the above component (A), component (B), component (C) and component (D).