JPH06192517A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide a composition containing a thermoplastic resin composition composed of a styrene-based resin and an alkylene oxide graft polyamide and an organic sulfonic acid metal salt and capable of producing a molding excellent in antistatic properties and durability thereof. CONSTITUTION:The thermoplastic resin composition capable of producing a resin molding excellent in antistatic properties and durability thereof and useful for a car vehicle component, an electric product, etc., is obtained by blending (C) <=5 pts.wt. organic sulfonic acid metal salt (e.g. sodium dodecylbenzenesulfonate) with 100 pts.wt. resin composition composed of (A) 50 to 95 pts.wt. styrene-based resin (e.g. styrene-acrylonitrile copolymer) and (B) 50 to 5 pts.wt. alkylene oxide graft polyamide synthesized by reacting powdery nylon 6 with ethylene oxide at 80 deg.C in an atmosphere of nitrogen gas without using a catalyst in an autoclave.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermoplastic resin composition having a permanent antistatic property.

[0002]

[Prior Art and Problems] Styrene-based resins are
It has excellent mechanical properties and moldability, and is used in various fields such as vehicle parts and electric products.

However, the styrene resin is an electrical insulator because its structure is based on an organic compound.
Cannot discharge charged electricity. Therefore, there is a problem in that dust adheres to the surfaces of vehicle parts and electric products made of styrene-based resin, which significantly reduces the commercial value. In addition, in electronic devices, there is a problem that electricity charged in the molded product may damage the device.

As a means for preventing static electricity, generally known is a method of applying an antistatic agent which is a surfactant onto a molded article, or a method of kneading a conductive substance such as carbon black or metal powder. In the former case, the antistatic effect easily deteriorates due to aging and washing. On the other hand, the latter sacrifices the excellent mechanical properties and molding processability inherent in the styrene resin, and it is difficult to color it in any color.

[0005]

[Means for Solving the Problems] The inventors of the present invention have made earnest studies on a resin composition which imparts a permanent antistatic property without impairing the original characteristics of the styrene resin. It was found that a composition comprising a specific amount of alkylene oxide grafted polyamide and a composition comprising a small amount of a metal salt of an organic sulfonic acid in such a composition have excellent permanent antistatic performance,
The invention has been reached.

That is, the present invention is based on the styrene resin 50.
To 95 parts by weight and 50 to 5 parts by weight of alkylene oxide-grafted polyamide (Claim 1), and a permanent composition containing 5 parts by weight or less of an organic sulfonic acid metal salt per 100 parts by weight of such a composition. The present invention provides a thermoplastic resin composition having an effective antistatic effect (claim 2).

The thermoplastic resin composition of the present invention will be described in detail below.

The styrene resin used in the present invention is obtained by polymerizing a styrene monomer alone or a styrene monomer and another copolymerizable monomer in the presence or absence of a rubbery polymer. It is a resin formed.

Examples of the rubbery polymer which can constitute the styrene resin include polybutadiene, polyisoprene, butadiene-styrene copolymer, isoprene-styrene copolymer, butadiene-acrylonitrile copolymer, butadiene-isoprene-styrene. Copolymers, diene rubbers such as polychloroprene, ethylene-propylene copolymers, ethylene-propylene rubbers such as ethylene-propylene-non-conjugated diene (ethylidene norbornene, dicycloopentadiene, etc.) copolymers, polybutyl acrylate Acrylic rubber and the like can be used, and one kind or two or more kinds can be used.

Styrene-based monomers include styrene and α
-Methyl styrene, paramethyl styrene, etc.,
One kind or two or more kinds can be used. Especially styrene,
α-methylthulene is preferred.

Other copolymerizable monomers that can be used together with the styrene-based monomer include vinyl cyanide compounds such as acrylonitrile and methacrylonitrile, and (meth) acryl such as methyl methacrylate and methyl acrylate. Acid ester compound, N-phenylmaleimide, N-
Examples thereof include maleimide compounds such as cyclohexylmaleimide, and these can be used alone or in combination of two or more.

Specifically, polystyrene (PS), styrene-acrylonitrile copolymer (AS), α-methylstyrene-acrylonitrile copolymer (αMS-AC)
N), methyl methacrylate-styrene copolymer (M
S), methyl methacrylate-acrylonitrile-styrene copolymer (MAS), styrene-N-phenylmaleimide copolymer (S-NPMI), styrene-N-phenylmaleimide-acrylonitrile copolymer (S-A-N)
PMI) "rubber non-reinforced styrene resin", acrylonitrile-butadiene rubber-styrene polymer (AB
S), acrylonitrile-ethylene / propylene rubber-styrene polymer (AES), acrylonitrile-acrylic ester rubber-styrene polymer (AAS), butadiene rubber-styrene copolymer (HIPS), etc. "
Examples thereof include “rubber-reinforced styrene-based resin” and any “mixture” of the above-mentioned rubber-unreinforced styrene-based resin and rubber-reinforced styrene-based resin.

ABS from the viewpoint of the balance of physical properties of the final composition,
A mixture of a rubber-reinforced styrene resin such as AES or AAS or a rubber-unreinforced styrene resin and a rubber-reinforced styrene resin is particularly preferable.

The alkylene oxide-grafted polyamide in the present invention is a polymer having a carbonamide group in the molecule modified with a 1,2-alkylene oxide having 2 to 4 carbon atoms.

Examples of 1,2-alkylene oxide having 2 to 4 carbon atoms include ethylene oxide, 1,2-propylene oxide and 1,2-butylene oxide.
One kind or two or more kinds can be used.

The polymer having a carbonamide group in the molecule (hereinafter referred to as polyamide) is a known linear polyamide having a repeating --CO--NH-- group in the main chain of the molecule.

Suitable polyamides are, for example, those prepared by polycondensing the following polyamide-forming starting materials in the presence of neutral or acidic catalysts.

Diamines having 2 to 12 carbon atoms (such as penta, hexa, or decamethylenediamine), dicarboxylic acids having 4 to 12 carbon atoms (adipic acid, pimelic acid, sebacic acid and their homologues). , Terephthalic acid, phenyleneacetic acid or mixtures from phenylenedipropionic acid.), Salts of the abovementioned diamines with dicarboxylic acids, polyamide-forming ω-amino having 4 to 12 carbon atoms which may be substituted by alkyl groups. Carboxylic acid (ω-aminobutyric acid, ω-aminocaproic acid, ω-aminocaprylic acid, ω-aminocalic acid, ω-
Aminodecanoic acid and ω-aminododecanoic acid and the like. ), Ω
Lactams corresponding to aminocarboxylic acids and mixtures thereof. Particularly preferred polyamides are polycaprolactam and polyhexamethylene adipamide.

A known method can be used for producing the alkylene oxide-grafted polyamide. For example, they are described in JP-A-47-897, German Patent No. 907701, German Patent No. 713957, Belgian Patent No. 665018, and Left European Patent No. 740577.

Specifically, it can be obtained by contacting a polyamide with an alkylene oxide at 60 to 120 ° C. for several hours under an inert gas atmosphere.

The amount of 1,2-alkylene oxide grafted in the alkylene oxide-grafted polyamide is preferably 10 to 200 parts by weight, more preferably 20 to 150 parts by weight, based on 100 parts by weight of the polyamide. When the amount is more than 200 parts by weight, the strength of the final composition is decreased, and 1
If the amount is less than 0 parts by weight, the antistatic property of the final composition tends to decrease.

The mixing ratio of the styrene resin and the alkylene oxide-grafted polyamide is 100 in total.
As the parts by weight, 50 to 95 parts by weight of the styrene resin and 50 to 5 parts by weight of the alkylene oxide-grafted polyamide are used. When the amount of alkylene oxide-grafted polyamide exceeds 50 parts by weight, the strength of the final composition (flexural modulus)
Is reduced. On the other hand, when the amount of the alkylene oxide-grafted polyamide is less than 5 parts by weight, the antistatic property of the final composition is poor.

The composition comprising the styrene resin and the alkylene oxide-grafted polyamide of the present invention has good permanent antistatic property. However, when higher antistatic performance is required, an organic sulfonic acid metal salt is added. Therefore, the antistatic performance can be improved.

Examples of the organic sulfonic acid metal salt in the present invention include nuclear-substituted or non-nuclear-substituted benzenesulfonic acid metal salt and alkylsulfonic acid metal salt, and one or more kinds can be used. Preference is given to alkali-substituted benzenesulfonic acid alkali metal salts such as the Li, K or Na salts of dodecylbenzenesulfonic acid.

The amount of the organic sulfonic acid metal salt added is 5 parts by weight or less based on 100 parts by weight of the total amount of the styrene resin and the alkylene oxide graft polyamide.
Even if the amount of the organic sulfonic acid metal salt exceeds 5 parts by weight, the antistatic property of the composition is not further improved, the dispersibility is rather deteriorated, and the composition may be extruded on the surface of the molded article to impair the appearance, or It is not preferable because it becomes sticky. The addition amount of the organic sulfonic acid metal salt is preferably 3 parts by weight or less.

Further, in the composition of the present invention, a known styrenic resin-polyamide compatibilizing agent can be used in order to improve the dispersibility of the styrene resin and the alkylene oxide graft polyamide. As a compatibilizer,
Examples thereof include a styrene resin in which a functional group having reactivity or affinity with polyamide such as a carboxyl group, a carboxylic acid anhydride, or an amino group is introduced by means such as copolymerization.

In the thermoplastic resin composition of the present invention, known additives such as antioxidants [2,6-di-t-butyl-
4-methylphenol, 2- (1-methylcyclohexyl) -4,6-dimethylphenol, 2,2-methylene-bis- (4-ethyl-6-t-methylphenol),
4,4'-thiobis- (6-t-butyl-3-methylphenol), dilaurylthiodipropionate, tris (di-nonylphenyl) phosphite and the like are exemplified. ], An ultraviolet absorber [pt-butylphenyl salicylate, 2,2′-dihydroxy-4-methoxybenzophenone, 2- (2′-hydroxy-4′-n-octoxyphenyl) benzotriazole, etc. It is illustrated. ], Lubricants [paraffin wax, stearic acid, hydrogenated oil, stearamide, methylenebis stearamide,
Examples thereof include ethylene bis stearamide, n-butyl stearate, ketone wax, octyl alcohol, lauryl alcohol, hydroxystearic acid triglyceride and the like. ], Flame retardants [antimony oxide, aluminum hydroxide, zinc borate, tricresyl phosphate, tris (dichloropropyl) phosphate, chlorinated paraffin, tetrabromotan, hexabromobenzene, tetrabromobisphenol A, etc. are exemplified. ], A colorant [titanium oxide, carbon black and the like. ],
Fillers [calcium carbonate, clay, silica, glass fibers, glass spheres, carbon fibers and the like are exemplified. ] Etc. can be added as needed.

Further, the present invention does not prevent the combined use of other antistatic agents. The composition of the present invention includes
Furthermore, polycarbonate, polymethylmethacrylate,
Other thermoplastic resins such as polyvinyl chloride, polyamide, polybutylene terephthalate, polyphenylene oxide, polyoxymethylene and the like can be mixed if necessary.

Mixing the components of the composition of the invention with an extruder,
It can be obtained by melt-kneading using a Banbury mixer, a roll or the like.

Next, the present invention will be described based on examples, but the present invention is not limited to such examples. In addition, all the parts in the blended composition represent the parts by weight. The physical properties of the composition were measured as follows.

(1) Preparation of Test Pieces for Measuring Physical Properties The pellets obtained in Examples and Comparative Examples were molded into test pieces for each physical property at a cylinder set temperature of 220 ° C. using a 3.5 ounce injection molding machine.

(2) Physical property measurement

(I) Surface low resistance value Flat plate of 90 × 40 × 3 mm and surface high and low resistance meter SM-1
OE (manufactured by Toa Denpa Kogyo Co., Ltd.) was used for measurement under the following conditions. Unit: Ω. (B) The test piece was placed at 23 ° C and 50% relative humidity for 24 hours.
Measure after adjusting the time condition. (B) After thoroughly washing the surface of the test piece with pure water, 23 °
Measured after conditioning for 24 hours under the conditions of C and 50% relative humidity.

(Ii) Flexural modulus The flexural modulus was measured according to ASTM D-790. The test piece was conditioned at 23 ° C and 50% relative humidity for 1 week.
It was subjected to measurement. Unit: Kg / cm ²

(Iii) Appearance The surface condition of the test piece for measuring the surface low resistance value was visually observed. ○: Good, ×: Poor (with surface stickiness)

The alkylene oxide-grafted polyamides used in the following examples and comparative examples were prepared as follows.

(Reference Example) Synthesis of alkylene oxide-grafted polyamide Nylon 6 (number average molecular weight 18,000) powder 20
g and 40 ml of ethylene oxide were charged into a stainless steel autoclave, and reacted with each other at 80 ° C. for a predetermined time in a nitrogen gas atmosphere without a catalyst. After the reaction, unreacted ethylene oxide was removed by evaporation, and washing was performed in boiling water for 4 hours while replacing the boiling water every hour. Then, it was vacuum dried at 50 ° C. for 72 hours to obtain the following three types of graft polyamide. A. Reaction time: 4 hours, graft ratio: 27.4% B.I. 〃: 5〃, 〃: 53.5% C.I. 〃: 6〃, 〃: 74.7% The graft ratio in the above reference example is nylon 6
It represents the number of parts by weight of ethylene oxide grafted to 100 parts by weight.

Further, in the examples and comparative examples, the following styrene resins and organic sulfonic acid metal salts were used. ABS: Sumitomo Dow Co., Ltd. Clarastic GA-
701 AES: Sumitomo Dow Co., Ltd. Unibright UB-5
00A DBS (sodium dodecylbenzene sulfonate): manufactured by Kao Co., Ltd. Neopex 05Z LAS (sodium linear alkyl sulfonate): manufactured by Nippon Mining Co., Ltd. SAS-95

(Example 1) 70 parts of ABS and 30 parts of alkylene oxide-grafted polyamide A synthesized in Reference Example were melt-kneaded at a cylinder temperature of 220 ° C using a 40 mm single screw extruder, and then pelletized. The physical properties of the obtained composition were measured by the methods described above. The results are shown in Table-1.

(Examples 2 and 3) The types of alkylene oxide-grafted polyamide used in Example 1 were changed to B and C, respectively. Others were the same as in Example 1, and the physical properties of the obtained composition were measured. The results are shown in Table-1.

(Examples 4 and 5 and Comparative Examples 1 and 2) In Example 2, the mixing ratio of ABS and alkylene oxide-grafted polyamide B was 90 parts / 10 parts and 6 parts, respectively.
It was changed to 0 part / 40 parts, 40 parts / 60 parts and 97 parts / 3 parts. Others were the same as in Example 2, and the physical properties of the obtained composition were measured. The results are shown in Table-1.

Comparative Example 3 In Example 1, the alkylene oxide-grafted polyamide A was changed to nylon 6 used as a raw material in the reference example. Others were the same as in Example 1, and the physical properties of the obtained composition were measured. The results are shown in Table-1.

(Embodiment 6) In the second embodiment, the ABS
Was changed to AES. Others were the same as in Example 2, and the physical properties of the obtained composition were measured. The results are shown in Table-1.

(Example 7) 70 parts of ABS, 30 parts of alkylene oxide-grafted polyamide B and 2 parts of sodium dodecylbenzenesulfonate were melt-kneaded in the same manner as in Example 1. Pelletized. The physical properties of the obtained composition were measured. The results are shown in Table-1.

(Example 8) In Example 7, sodium dodecylbenzenesulfonate was changed to sodium linear alkylsulfonate. Others were the same as in Example 7, and the physical properties of the obtained composition were measured. The results are shown in Table-1.

(Comparative Example 4) In Example 7, the amount of sodium dodecylbenzenesulfonate was increased to 8 parts. Others were the same as in Example 7, and the physical properties of the obtained composition were measured. The results are shown in Table-1.

Comparative Example 5 100 parts of ABS and 2 parts of sodium dodecylbenzenesulfonate were melt-kneaded in the same manner as in Example 1 and pelletized. The physical properties of the obtained composition were measured. The results are shown in Table-1.

[0048]

[Table 1]

[0049]

INDUSTRIAL APPLICABILITY The thermoplastic composition of the present invention has excellent antistatic property and its durability (permanence), and also has good mechanical strength such as flexural modulus. It has high utility value as a material for various industrial parts.

[Procedure amendment]

[Submission date] October 26, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Title of invention

[Correction method] Change

[Correction content]

Title: Thermoplastic resin composition

Claims (2)

[Claims] 1. A styrene resin (A) in an amount of 50 to 95 parts by weight and an alkylene oxide graft polyamide (B) 5
A thermoplastic resin composition comprising 0 to 5 parts by weight. 2. A styrene resin (A) in an amount of 50 to 95 parts by weight and an alkylene oxide graft polyamide (B) 5
A thermoplastic resin composition comprising 5 parts by weight or less of an organic sulfonic acid metal salt (C) per 100 parts by weight of a composition comprising 0 to 5 parts by weight.