JP2001139764A - Antimicrobial, chemical-resistant and thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antimicrobial, chemical-resistant and thermoplastic resin composition having chemical resistance, and excellent in antimicrobial activities, impact resistance and color stability at the time of melting. SOLUTION: This antimicrobial, chemical-resistant and thermoplastic resin composition is obtained by blending a rubber-reinforced styrene resin having a rubber particle diameter, a graft rate and a reduced viscosity of acetone- soluble components within specific ranges respectively, with a terpolymer of ethylene/(meth)acrylate/carbon monoxide, and a specific antimicrobial zeolite.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antimicrobial chemical-resistant thermoplastic resin composition having excellent resistance to stress cracking and excellent antimicrobial performance, impact resistance and color stability of the melt. About things.

[0002]

2. Description of the Related Art Acrylonitrile is added to a diene rubber component.
The so-called ABS resin, which contains a graft copolymer obtained by copolymerizing a vinyl cyanide compound such as methacrylonitrile and an aromatic vinyl compound component such as styrene and α-methylstyrene, has excellent mechanical properties and moldability. It is used in a wide range of fields such as home electric appliances, OA appliances, automobiles and other parts due to surface glossiness. In particular, in applications where impact resistance and gloss are required,
ABS resins are preferred and used.

[0003] However, when ABS resin is used for toilets, toilets, and bath peripheral parts, antibacterial properties are often required in terms of dirt and cleanliness in recent years. Also, A
BS resin is widely used for parts of heat-insulating structures such as inner boxes and door members of refrigerators, miscellaneous goods such as pachinko trays, and sanitary uses such as toilets and kitchens. ABS resin is used for other crystalline polymers. It is known that its chemical resistance is inferior to that of plastics and engineering plastics.In general goods and sanitary applications, household or commercial detergents are used for cleaning such parts. Crazes and cracks occur, causing a problem of significantly impairing the commercial value.

As means for solving such a problem,
A method of applying an antibacterial paint or kneading an organic / inorganic antibacterial agent is known. However, the method of applying an antibacterial paint requires complicated steps, is expensive, and is not effective. Silver,
Zeolite substituted by a metal selected from copper and zinc and a non-halogenated organic polymer (Japanese Patent Publication No. 63-5401)
3) A resin composition using a zeolite substituted with a metal selected from silver, copper, and zinc and thiabenzimidazole (Japanese Patent Application Laid-Open No. 8-169981) has been proposed, but the chemical resistance is insufficient. In addition, when the antibacterial agent of the present invention is added to an existing styrenic resin, there is a problem that the color tone change during melting is large. On the other hand, the AN content is 58 to 65 mol%
-Resistant resin composition using AS (Japanese Patent Laid-Open No. 5-31)
0862) has been proposed, but there is a problem that even the resin composition of the present invention alone has poor color tone stability, and the addition of an antibacterial agent further deteriorates the color tone. Also, a method has been proposed in which an ethylene / acrylic ester / carbon monoxide copolymer is added to an imide resin to improve the chemical resistance while maintaining the color tone (JP-A-6-116469).
The impact resistance is insufficient, and there is a problem that the addition of an antibacterial agent further reduces the impact resistance.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art, has chemical resistance excellent in stress crack resistance, and has antibacterial performance, impact resistance and color stability of the melt. It is an object of the present invention to provide an antibacterial chemical-resistant thermoplastic resin composition having excellent heat resistance.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, the rubber particle diameter, the graft ratio, and the reduced viscosity of the acetone-soluble component of the rubber-reinforced styrene-based resin are within specific ranges. In the present invention, it has been found that the above object can be efficiently achieved by blending a terpolymer of ethylene / (meth) acrylate / carbon monoxide and a specific antibacterial zeolite. Reached.

That is, according to the present invention, the weight average particle size is 0.1.
Diene rubber (A-1) having a particle size of 1 to 2.0 μm
Parts by weight of an aromatic vinyl compound (a) and / or an α, β-unsaturated carboxylic acid ester compound (b)
85% by weight, vinyl cyanide compound (c) 15 to 55
% By weight, other copolymerizable vinyl monomer (d) 0
To 40% by weight of a monomer mixture (A-2) 95 to
Graft polymerization of 20 parts by weight, the graft ratio of which is 15 to
10 to 60 parts by weight of the graft copolymer (A), which is 100%, and the aromatic vinyl compound (a) and / or α, β
-45 to 75% by weight of an unsaturated carboxylic acid ester compound (B), 25 to 55% by weight of a vinyl cyanide compound (C),
20 to 99 parts by weight of a copolymer (B) obtained by copolymerizing a monomer mixture comprising 0 to 40% by weight of another copolymerizable vinyl monomer (d), and ethylene / (meth) acrylic acid Ester / carbon monoxide copolymer (C)
Antibacterial activity obtained by partially or completely substituting 1 to 20 parts by weight of a natural or synthetic zeolite ion-exchangeable cation with at least one metal ion selected from silver ions, zinc ions or copper ions Zeolite (D)
It comprises 0.01 to 2.0 parts by weight, the reduced viscosity of the acetone-soluble component is 0.1 to 1.0 dl / g, and the triple cyanide compound of the vinyl cyanide compound in the copolymer (B) The proportion of cans is 10% by weight or less in the copolymer (B), and the graft copolymer (A), the copolymer (B), and the copolymer (C)
And an antimicrobial zeolite having a total of 100 parts by weight.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

Examples of the diene rubber (A-1) in the present invention include, in addition to polybutadiene, a styrene-butadiene copolymer, an acrylonitrile-butadiene copolymer,
Examples thereof include a styrene-butadiene block copolymer, a butyl acrylate-butadiene copolymer, and a polyisoprene rubber. Among them, polybutadiene and a styrene-butadiene copolymer rubber are preferable.

In the present invention, the aromatic vinyl compound (a) in the monomer mixture of the monomer mixture (A-2) and the copolymer (B) includes styrene, α-methylstyrene,
Examples thereof include p-methylstyrene, vinyltoluene, t-butylstyrene, o-ethylstyrene, o-chlorostyrene and o, p-dichlorostyrene, with styrene and α-methylstyrene being particularly preferred. One or more of these can be used.

The α, β-unsaturated carboxylic acid ester compounds (b) include methyl (meth) acrylate, (meth)
Ethyl acrylate, n-propyl (meth) acrylate,
N-butyl (meth) acrylate, t- (meth) acrylate
-Butyl, n-hexyl (meth) acrylate, (meth)
Examples thereof include cyclohexyl acrylate, chloromethyl (meth) acrylate, and 2-chloroethyl (meth) acrylate, with methyl methacrylate being preferred.

Examples of the vinyl cyanide compound (c) include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like, with acrylonitrile being particularly preferred.

The other copolymerizable vinyl monomers (d) include maleimide compounds such as N-methylmaleimide, N-cyclohexylmaleimide and N-phenylmaleimide; unsaturated dicarboxylic acids such as maleic acid; Examples include unsaturated dicarboxylic anhydrides such as maleic anhydride, and copolymerizable vinyl compounds represented by unsaturated amide compounds such as acrylamide. These can be used alone or in combination of two or more.

The weight average particle diameter of the diene rubber (A-1) in the graft copolymer (A) is from 0.1 to 2.0 μm.
And preferably 0.2 to 1.5 μm
m. If the weight average particle diameter is out of the range of 0.1 to 2.0 μm, chemical resistance and mechanical properties will not be exhibited. The content of the diene rubber (A-1) is 5 to 80 parts by weight, preferably 10 to 60 parts by weight, based on 100 parts by weight in total.

An aromatic vinyl compound (a) and / or an α, β-unsaturated carboxylic acid ester compound (b), a vinyl cyanide compound (c) in the monomer mixture (A-2),
Each composition ratio of the other copolymerizable vinyl monomer (c) is such that (a) and / or (b) are 45 to 85% by weight,
It is preferably 50 to 80% by weight, (C) 15 to 55% by weight, preferably 20 to 50% by weight, and (D) 0 to 40% by weight. Aromatic vinyl compound (A) and / or α, β-unsaturated carboxylic acid ester compound (B), vinyl cyanide compound (C), and other copolymerizable vinyl monomers in copolymer (B) Each composition ratio of the body (c) is
(A) and / or (B) are 45 to 75% by weight, preferably 50 to 70% by weight, (C) is 25 to 55% by weight,
Preferably 20 to 50% by weight, (d) 0 to 20% by weight
It is. The monomer compositions may be the same or different as long as the mechanical properties are not impaired. Among the monomer mixture of the copolymer (B), the vinyl cyanide compound is an especially important monomer, and if the total amount of the monomer mixture is less than 25% by weight, the chemical solution is When contact is made, crazes and cracks are easily generated in the molded product, which is not preferable. On the other hand, if it exceeds 55% by weight, not only is the effect of improving the chemical resistance gradually reduced, but also disadvantages such as a marked decrease in the thermal coloring and fluidity during molding are undesirable.

The graft ratio in the graft copolymer (A) needs to be 15 to 100%, preferably 20 to 70%. If the graft ratio is outside the range of 15 to 100%, not only does the chemical resistance not develop, but also the mechanical properties are significantly reduced.

The method for producing the graft copolymer (A) may be any of polymerization methods such as emulsion polymerization, suspension polymerization, bulk polymerization, and solution polymerization, and is not particularly limited. There are no particular restrictions on the method of charging the monomer, the initiator and the chain transfer agent, and a part or the whole of the charged monomer is continuously charged in order to suppress the generation of the initial composition or the distribution of the composition of the copolymer. The polymerization may be carried out while charging the target or divided.

In the present invention, the triple sequence of the vinyl cyanide compound in the copolymer (B) is a segment of the copolymer represented by the formula (1), and the copolymer is exposed to a high temperature. It is presumed that in this state, the intramolecular reduction reaction shown in Chemical formula (2) proceeds, leading to coloring.

[0019]

Embedded image

[0020]

Embedded image The antibacterial chemical-resistant thermoplastic resin composition of the present invention has a copolymer (B) as a constituent component, in which the ratio of a triple sequence of a vinyl cyanide compound that inhibits thermal coloring prevention is 10%.
Since it is as small as less than 10% by weight, it is excellent in thermal coloring prevention during melt kneading and molding. More preferably, the ratio of the triple sequence of the vinyl cyanide compound is less than 8% by weight,
If the proportion exceeds 10% by weight, the thermal discoloration prevention during melt-kneading and molding is reduced, which is not preferred. When the ratio of the triple sequence of such a vinyl cyanide compound is 1
The copolymer (B) controlled to 0% by weight or less can be produced by performing polymerization while controlling the ratio of the vinyl cyanide monomer component in the remaining monomer. The polymerization method is preferably aqueous suspension polymerization, but is not particularly limited to this method.

Examples of the suspension stabilizer used in the aqueous suspension polymerization include inorganic suspension stabilizers such as clay, barium sulfate and magnesium hydroxide, polyvinyl alcohol, carboxymethyl cellulose, polyacrylamide, methyl methacrylate / acrylamide. An organic suspension stabilizer such as a polymer may be mentioned, and among them, an organic suspension stabilizer is preferable because of being excellent in thermal coloring prevention property at the time of melting, and more preferably a methyl methacrylate / acrylamide copolymer. Further, the total amount of water as a dispersion medium with respect to 100 parts by weight of the total amount of charged monomers is 80% from the viewpoint of maintaining good dispersibility of the monomers in water and dissolving and transferring a large amount of the vinyl cyanide monomer into water. It is preferable to select from the range of from 350 to 350 parts by weight, and more preferably from 100 to 200 parts by weight for controlling the ratio of the vinyl cyanide-based monomer component in the residual monomer.

Examples of the polymerization initiator used in the aqueous suspension polymerization include 2,2'-azobis (2,4-dimethylvaleronitrile) and 2,2'-azobis (2,4,4-trimethylvaleronitrile). And organic peroxides such as t-butyl peroxide, t-butyl peroxy neodecanoate, t-butyl peroxy neosexanoate, and t-butyl peroxy pivalate. One or two or more of them can be used in combination, and among them, an azonitrile compound is preferable. Although there is no particular limitation on the chain transfer agent used here, alkyl mercaptans are preferred.

There are no particular restrictions on the method of charging the monomer, initiator and chain transfer agent for the aqueous suspension polymerization. There are no particular restrictions on the initial batch charge or the charge of the charged monomer in order to suppress the formation of a composition distribution of the copolymer. Polymerization may be performed while charging a part or all of the mixture continuously or separately.

In the present invention, in order to obtain the copolymer (B), in order to control the ratio of the triple sequence of the vinyl cyanide-based monomer, the amount of the residual monomer in the polymerization system from the start to the end of the polymerization is controlled. 95% of vinyl cyanide monomer component in the body
It is preferable to control the amount of the vinyl cyanide-based monomer component in the residual monomer from the start of polymerization to the point when the polymerization rate has passed by 10% from 70% by weight to 95% by weight. When the ratio of the vinyl cyanide-based monomer component in the residual monomer from the start of the polymerization to at least 10% of the polymerization rate is 7%,
If it is 0% by weight or less, it becomes difficult to maintain chemical resistance. Chemical resistance, which is an advantage of the resin composition of the present invention,
About the copolymer (B) which is the matrix component,
A high content ratio of vinyl cyanide-based monomer components generated by maintaining the ratio of vinyl cyanide-based monomer components in the residual monomers from the start of polymerization to the point of time when the polymerization rate has passed by 10% at 70% by weight or more, This is because it is expressed by the high nitrile copolymer component. The high-nitrile copolymer component described here is a component that is obtained by dissolving the copolymer (B) in methyl ethyl ketone and then dropping by cyclohexane dropwise. The ratio of the vinyl cyanide monomer component in the precipitate is FT- It can be quantified by IR analysis. The ratio of the vinyl cyanide monomer component in the residual monomer is determined by the amount of the polymerization initiator, the addition of the polymerization inhibitor, the removal of the vinyl cyanide monomer from the polymerization system by stripping, or the removal of the vinyl cyanide monomer. It can be controlled by adding a monomer other than the monomer component into the polymerization system during polymerization.

The copolymer (C) in the present invention is a terpolymer of ethylene / (meth) acrylate / carbon monoxide, and the acryl group of (meth) acrylate has a linear or It is branched and has 1 to 1 carbon atoms.
18 is preferable, and a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a sec-butyl group, a t-butyl group,
Examples thereof include an isobutyl group, a hexyl group, a 2-ethylhexyl group, and an octyl group, and those having 2 to 8 carbon atoms are more preferable. Further, each composition ratio of the copolymer (C) is such that ethylene is 10 to 85% by weight, more preferably 40 to 80% by weight,
(Meth) acrylic acid ester is 10 to 50% by weight, more preferably 15 to 40% by weight, carbon monoxide is 5 to 40% by weight, more preferably 5 to 20% by weight. It can also be copolymerized with a copolymerizable monomer.

Antibacterial zeolite (D) in the present invention
Is an ion-exchangeable cation of a natural or synthetic zeolite with at least one metal ion selected from silver ions, copper ions, and zinc ions, and preferably at least one metal ion selected from silver ions or zinc ions. Antimicrobial zeolite obtained by partial or complete substitution with metal ions, and 0.1 to 2.0% by weight, more preferably 0.3 to 2.0% by weight, based on 100% by weight of the above-mentioned chemical resistant resin composition.
1.0% by weight. When the amount of the component (D) is less than 0.1% by weight, the antibacterial performance is not sufficiently exhibited. On the other hand, when the amount exceeds 2.0% by weight, the color tone is deteriorated, and the impact resistance is lowered.

Graft copolymer (A), copolymer (B), copolymer (C) and antibacterial zeolite (D)
(A) / (B) / (C) / (D) is 10 to 6
0/20 to 99 / 0.1 to 20 / 0.01 to 2,
If the amount of the component (A) exceeds 60, the rigidity and the fluidity are undesirably reduced. If the component (C) is less than 0.1, chemical resistance is not exhibited, while if it exceeds 20, the rigidity is reduced and further delamination occurs, which is not preferable. If the component (D) is less than 0.01, the antibacterial property is not exhibited,
If it exceeds 2, the impact resistance is undesirably reduced.

The reduced viscosity of the acetone-soluble component of the antibacterial chemical-resistant thermoplastic resin composition of the present invention is 0.1 to 1.0 dl /.
g, and if it is outside the range, chemical resistance and mechanical properties are not exhibited.

The antibacterial chemical-resistant thermoplastic resin composition and the molded article of the present invention are preferably used for applications requiring chemical resistance. The chemical solution effective for the present invention is preferably an organic compound, and is a chemical containing a hydrocarbon, a halogenated hydrocarbon, an ester compound, an ether compound and an alcohol compound. Further, a hydrocarbon having 4 to 20 carbon atoms,
Fluorocarbons, gasoline, kerosene, brake oil, plasticizers for polyvinyl chloride (eg dialkyl phthalate,
Phthalic acid alkyl ester) and a detergent.

In order to improve the chemical resistance of the antibacterial and chemical-resistant thermoplastic resin composition of the present invention and the molded product, the temperature is set to 23 ° C.
Cracking critical strain after contact with chemical solution for 24 hours at 0.5
%, Preferably 0.7% or more, more preferably 1.0% or more. If it is less than 0.5%, the effect of improving chemical resistance is small.

The uses of these molded articles are as follows: electricity,
Although there are no particular restrictions on electronic parts, automobiles, machinery, miscellaneous goods, chemical plants, aviation and space parts, materials, etc., the molded article of the present invention is effective for applications requiring chemical resistance due to its characteristics.
Among them, it can be used as a housing for electric and electronic products and structural parts of refrigerators, miscellaneous goods such as pachinko trays, sanitary uses such as toilets and kitchens, and interior and exterior materials for automobiles.

The antibacterial and chemical-resistant thermoplastic resin composition of the present invention is not impaired in the object of the present invention, as long as the object of the present invention is not impaired, such as polyolefins such as vinyl chloride, polyethylene and polypropylene; polyamides such as nylon 6 and nylon 66; Polyester such as polycyclohexanedimethyl terephthalate, polycarbonate, and various elastomers can be added to improve the performance as a molding resin. In addition, if necessary, an antioxidant such as a hindered phenol type, a sulfur-containing organic compound type, a phosphorus-containing organic compound type, a heat stabilizer such as a phenol type or an acrylate type, a benzotriazole type, a benzophenone type, a salicylate type, etc. UV stabilizers, various stabilizers such as organic nickel-based, hindered amine-based light stabilizers, etc., lubricants such as metal salts of higher fatty acids, higher fatty acid amides, etc., plasticizers such as phthalate esters and phosphate esters, poly Halogen-containing compounds such as bromodiphenyl ether, tetrabromobisphenol-A, brominated epoxy oligomer, and brominated polycarbonate oligomer,
Phosphorus compounds, flame retardants such as antimony trioxide, flame retardant assistants, carbon black, titanium oxide, pigments and dyes can also be added. Further, reinforcing agents and fillers such as glass fibers, glass flakes, glass beads, carbon fibers, and metal fibers can also be added. Regarding the method for producing the thermoplastic resin composition of the present invention, a Banbury mixer,
Various methods such as melt kneading with a roll and a single or multi-screw extruder can be adopted.

The antibacterial and chemical-resistant thermoplastic resin composition obtained as described above is subjected to injection molding, extrusion molding, blow molding,
It can be formed by a known method currently used for forming a thermoplastic resin such as vacuum forming, compression forming, and gas assist forming, and is not particularly limited.

[0034]

EXAMPLES The present invention will be described more specifically with reference to examples and comparative examples, but these examples do not limit the present invention. Here, unless otherwise specified, "%" represents% by weight and "parts" represents parts by weight. The method for analyzing the resin properties of the antibacterial chemical-resistant thermoplastic resin composition is described below. For general properties such as mechanical strength and heat resistance, test pieces are molded by injection molding,
It was measured according to the following test method.

(1) Rubber particle diameter: sodium alginate method.

(2) Graft ratio: A predetermined amount (m) of the graft copolymer was mixed with acetone and refluxed for 3 hours. p. m. After centrifugation at (10000 G) for 40 minutes, the insoluble matter was filtered, and the insoluble matter was dried under reduced pressure at 60 ° C. for 5 hours, and the weight (n) was measured. The graft ratio was calculated from equation (1).

Graft ratio (%) = [[(n) − (m) ′] / [(m) ′]] × 100 (1) where L is the rubber content of the graft copolymer.

(3) Reduced viscosity η _{sp / c} : 200 ml of acetone was added to 1 g of the sample, and the mixture was refluxed for 3 hours.
800r. p. m. After centrifugation at (10000 G) for 40 minutes, the insoluble matter is filtered. The filtrate was concentrated with a rotary evaporator, and the precipitate (acetone-soluble matter) was cooled to 60 ° C.
After drying under reduced pressure for 5 hours, using a Ubbelohde viscometer, a methyl ethyl ketone solution (0.4 g / dl), η _{sp / c} at 30 ° C.
Was measured.

(4) Quantification of the triple sequence of the vinyl cyanide monomer in the copolymer (B): The signal shift of the α-carbon of the vinyl cyanide monomer appearing in 13 C-NMR was Taking advantage of slightly different species
The percentage of the run sequence was quantified from its signal integral.

Apparatus: JEOL JNM-GSX400 type Observation frequency: 100.5 MHz Solvent: DMSO-d6 Concentration: 445 mg / 2.5 mL Chemical shift standard: Me4 Si Temperature: 110 ° C. Observation width: 20000 Hz Data point: 32K flip angle: 90 ° (21 μs) pulse delay time: 5.0 s Integration frequency: 7400 or 8400 Decoupling: gated decoupling (without NOE).

(5) Quantification of unreacted monomer, vinyl cyanide copolymerization amount and conversion in the polymerization system for polymerization of copolymer (B): Gas chromatograph (GC-14A type) manufactured by Shimadzu Corporation It measured using. The vinyl cyanide copolymerization amount and the conversion were calculated by the following equations (2) and (3).

[0042]

(Equation 1)

[0043]

(Equation 2) (6) Quantification of the ratio of high nitrile copolymer component in copolymer (B): 1 g of copolymer (B) was added to 40 g of methyl ethyl ketone.
After the dissolution, 20 g of cyclohexane is continuously dropped. 50
After stirring well at ℃, it was left at room temperature for 12 hours, and furthermore, at 30 ℃ in a constant temperature bath, and the precipitated copolymer component was centrifuged, and the content was determined from the dry weight.

(7) Quantification of the ratio of vinyl cyanide monomer component in the high nitrile copolymer component: The copolymer component subjected to the above-mentioned treatment is subjected to heat press molding to form a film having a thickness of about 30 μm. -IR analysis, 2260 cm ^-1 and 1
It was quantified from the ratio of the baseline height of the absorbance peak generated at 600 cm ^-1 using the calibration curve shown in the formula (4).

X = (R + 0.5874423) /0.07396422 (4) X: Ratio of vinyl cyanide monomer component (% by weight) R: Absorbance peak height ratio ｛= H (2260 cm ⁻¹ ) / H (1600
cm ^-1 )｝ (8) Flexural modulus: ASTM D790 (23 ° C.).

(9) IZOD impact strength: ASTM D256
(23 ° C, with 1/2 inch notch).

(10) MFR (melt flow rate):
ISO 1133 (220 ° C., 10 kg load).

(11) Yellowness (YI value): JIS K7
Inspection-formed square plate (120 × 100 ×
3 mm) with a colorimeter (ND-ND) manufactured by Nippon Denshoku Industries Co., Ltd.
100 type), the tristimulus values X, Y, and Z were measured. I. Values were calculated.

Y. I. = 100 × (1.28X-1.06Z) × Y (5) (12) Chemical resistance test: Injection molded strip-shaped test piece (126
× 12.6 × 1.5 mm) along the 1/4 elliptical jig shown in FIG. 1, and then apply a chemical solution to the surface of the test piece, or
Alternatively, in the case of a highly volatile chemical, the jig was placed in a desiccator having a diameter of 300 mm containing 250 ml of the chemical. After standing for 24 hours in an environment at 23 ° C., the occurrence of craze and cracks was confirmed, and the critical strain (%) was calculated from equation (6).

[0050]

(Equation 3) A: Long axis of jig (127 mm) B: Short axis of jig (38
mm) t: thickness of test piece (1.5 mm) X: length of shortest major axis to crack occurrence point (m
m) Reference Example (A) Graft Copolymer A1: 120 parts of pure water, 0.5 part of glucose, 0.5 part of sodium pyrophosphate, 0.005 part of ferrous sulfate and polybutadiene latex were placed in a nitrogen-purged reactor. 50 parts (solid content conversion) of a rubber particle diameter of 0.3 μm and a gel content of 85% were charged, and the temperature in the reactor was raised to 65 ° C. while stirring. When the internal temperature reached 65 ° C., polymerization was started, and a mixture consisting of a monomer (35 parts of styrene and 15 parts of acrylonitrile) and 0.3 part of t-dodecylmercaptan was continuously added dropwise over 5 hours. At the same time, an aqueous solution consisting of 0.25 parts of cumene hydroperoxide, 2.5 parts of potassium oleate and 25 parts of pure water was continuously added dropwise over 7 hours to complete the reaction. The obtained graft copolymer latex was coagulated with sulfuric acid, neutralized with caustic soda, washed, filtered and dried to obtain a rubber-containing graft copolymer (I). The graft ratio of this graft copolymer (I) was 45%, and ηsp / c of the resin component was 0.68 dl / g. (B) Copolymer B1: A methyl methacrylate / acrylamide copolymer (Japanese Patent Publication No. 45-2) was placed in a stainless steel autoclave having a capacity of 20 L and equipped with a baffle and a Fowler-type stirring blade.
No. 4151) 0.05 parts of ion-exchanged water 165
The solution dissolved in the part was stirred at 400 rpm, and the inside of the system was replaced with nitrogen gas. Next, 42 parts of acrylonitrile and styrene 4. O part, 0.46 part of t-dodecyl mercaptan,
A mixed solution of 0.39 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) and 0.05 part of 2,2′-azobisisobutylnitrile was added while stirring the reaction system, and the temperature was raised to 58 ° C. The mixture was heated to start polymerization. 15 from the start of polymerization
After a lapse of minutes, 54 parts of styrene from a feed pump mounted on the top of the autoclave was added over 110 minutes.
During this time, the reaction temperature was raised to 65 ° C. After the addition of styrene to the reaction system was completed, the temperature was raised to 100 ° C. over 50 minutes. Thereafter, the reaction system was cooled, the polymer was separated, washed, and dried according to a conventional method to obtain a copolymer B1 shown in Table 1. B2: Among the conditions of copolymer B1, mixed solution: acrylonitrile 28 parts styrene 18 parts N-phenylmaleimide 5 parts Additional addition of styrene: 49 parts, and polymerization was carried out in the same manner as copolymer B1.
A copolymer B2 shown in Table 1 was obtained. B3: Among the conditions for copolymer B1, mixed solution: acrylonitrile 47 parts, styrene 5 parts, styrene additional addition: 48 parts, and then polymerization was carried out in the same manner as copolymer B1,
A copolymer B3 shown in Table 1 was obtained. B4: Among the conditions of copolymer B1, mixed solution: acrylonitrile 35 parts styrene 10 parts methyl methacrylate 10 parts styrene additional addition: 45 parts, and polymerization was carried out in the same manner as copolymer B1.
A copolymer B4 shown in Table 1 was obtained. B5: Polymerization was carried out in the same manner as for copolymer B1, except that 1.5 parts of t-dodecylmercaptan was used among the conditions for copolymer B1, to obtain copolymer B5 shown in Table 1. B6: Polymerization was carried out in the same manner as for copolymer B1, except that t-dodecyl mercaptan was used in an amount of 0 parts, under the conditions for copolymer B1, to obtain copolymer B6 shown in Table 1. B7: Among the conditions of the copolymer B1, a mixed solution: acrylonitrile 20 parts styrene 80 parts styrene additional addition: 0 parts, and polymerization was carried out in the same manner as the copolymer B1,
A copolymer B7 shown in Table 1 was obtained. B8: Among the conditions of the copolymer B1, a mixed solution: acrylonitrile 42 parts styrene 58 parts styrene additional addition: 0 parts, and then polymerization was carried out in the same manner as the copolymer B1,
The copolymer B8 shown in Table 1 was obtained. B9: Among the conditions of the copolymer B1, a mixed solution: 70 parts of acrylonitrile 30 parts of styrene Additional addition of styrene: 0 part, and then polymerization was carried out in the same manner as for the copolymer B1,
The copolymer B9 shown in Table 1 was obtained.

[0051]

[Table 1] (C) Ethylene / (meth) acrylate / carbon monoxide copolymer C1: "Elvaloy" manufactured by DuPont-Mitsui Polychemicals
EP4051 C2: "Elvaloy" manufactured by Dupont Mitsui Polychemicals
EP443 (D) Antibacterial zeolite D1: "Zeomic" XAW10D manufactured by Sinanen Examples 1-4 and Comparative Examples 1-10 (A) graft copolymer, (B) copolymer, (C) described in Reference Examples After blending ethylene / (meth) acrylate / carbon monoxide copolymer and (D) antibacterial zeolite in the proportions shown in Table 2, melt-knead with a 40 mmφ single screw extruder (cylinder set temperature is 230 ° C.) A pellet-shaped resin was obtained.

The obtained pellets were subjected to injection molding machine IS-50A manufactured by Toshiba Machine Co., Ltd. (cylinder set temperature was 230 ° C.).
A test piece was formed by using, and various characteristics were evaluated. The results are shown in Tables 2 and 3.

[0053]

[Table 2]

[0054]

[Table 3] Examples 1 to 4 show that the antibacterial chemical-resistant thermoplastic resin composition having the compounding ratio described in the claims of the present invention is excellent in antibacterial properties, chemical resistance, mechanical properties and moldability.

However, in Comparative Examples 1 to 10, the graft copolymer (A), the copolymer (B), the copolymer (C) composed of ethylene / (meth) acrylate / carbon monoxide, and the antibacterial property Since the compounding ratio of zeolite (D) is out of the range described in the claims of the present invention, Comparative Examples 1 and 3 have rigidity, and Comparative Examples 2, 4, and 6 have low chemical resistance. Comparative Example 5 has poor fluidity, Comparative Examples 7 and 8 have poor color tone, and Comparative Example 9 has low antibacterial properties. Comparative Example 10 has low impact resistance.

From the Examples and Comparative Examples, the chemical resistant thermoplastic resin composition of the present invention is excellent in the balance of impact resistance, color stability when the resin is melted, chemical resistance and moldability. This is realized only by combining a specific amount of a copolymer having a specific structure, a graft copolymer, a copolymer of ethylene / (meth) acrylate / carbon monoxide, and an antibacterial zeolite. is there.

[0057]

The antimicrobial chemical-resistant thermoplastic resin composition or molded article of the present invention has chemical resistance, especially when it comes into contact with a chemical solution, does not generate crazes or cracks in the molded article, and further has antibacterial and anti-microbial properties. It is excellent in impact resistance, color stability of meltability, etc., and is suitable for fields requiring antibacterial properties and chemical resistance.

[Brief description of the drawings]

FIG. 1 is a schematic view of a jig used for a chemical resistance test in the present invention.

[Explanation of symbols]

 1 Test piece 2 Chemical solution application a Long axis of jig (127 mm) b Short axis of jig (38.1 mm) X Length of crack generation position (mm)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 73/00 C08L 73/00 F term (Reference) 4J002 BB07Y BC02X BC05X BC08X BC09X BC11X BG10X BG13X BH02X BN14W CJ00Y DJ006 FD186 GC01

Claims (2)

[Claims] 1. An aromatic vinyl compound (a) and / or α, β-unsaturated in 5 to 80 parts by weight of a diene rubber (A-1) having a weight average particle diameter of 0.1 to 2.0 μm. Monomer consisting of 45 to 85% by weight of a carboxylic acid ester compound (B), 15 to 55% by weight of a vinyl cyanide compound (C), and 0 to 40% by weight of another copolymerizable vinyl monomer (D) A graft copolymer (A-2) having a graft ratio of 15 to 100% is obtained by graft polymerization of 95 to 20 parts by weight of a body mixture (A-2), and an aromatic vinyl compound (A) and / or Or 45 to 75% by weight of an α, β-unsaturated carboxylic acid ester compound (II),
Copolymer (B) 20 prepared by copolymerizing a monomer mixture comprising 25 to 55% by weight of a vinyl cyanide compound (C) and 0 to 40% by weight of another copolymerizable vinyl monomer (D)
To 99 parts by weight, 0.1 to 20 parts by weight of a copolymer (C) composed of ethylene / (meth) acrylate / carbon monoxide, and a silver ion for ion exchangeable cation of natural or synthetic zeolite. Reduction of acetone-soluble component consisting of 0.01 to 2.0 parts by weight of antibacterial zeolite (D) obtained by partial or complete substitution with at least one metal ion selected from zinc ion or copper ion Viscosity is 0.1 ~
1.0 dl / g, and the ratio of the triple sequence of the vinyl cyanide compound in the copolymer (B) is 10% by weight or less in the copolymer (B), and the graft copolymer ( A), a copolymer (B), an antibacterial chemical-resistant thermoplastic resin composition in which the total of the copolymer (C) and the antibacterial zeolite (D) is 100 parts by weight. 2. A molded article obtained by molding the antibacterial chemical resistant thermoplastic resin composition according to claim 1.