JPH08245868A - Resin composition excellent in antistatic property and its molded item - Google Patents

Abstract

PURPOSE: To obtain a polycarbonate resin compsn. which has permanent antistatic properties and is excellent in mechanical characteristics, such as impact strength, and clarity. CONSTITUTION: This compsn. comprises 80-99 pts.wt. polycarbonate resin, 0.5-20 pts.wt. cross-linked polyethylene oxide, and 0.01-3.0 pts.wt. at least one electrolyte selected from among org. and inorg. electrolytes.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention has an antistatic property of antistatic property having permanent antistatic property, excellent mechanical properties represented by impact resistance and heat resistance, and excellent transparency. Relates to a resin composition having excellent properties.

[0002]

2. Description of the Related Art Polycarbonate resins are widely used as parts for office automation equipment, home appliances, medical equipment, etc. because they are excellent in heat resistance, impact resistance, etc., and are also self-extinguishing and flame retardant. . However, since it is an insulating material like general synthetic resin materials, it is charged by the generation of static electricity. When charged, there is a problem that dust is likely to adhere to the product, impairing the appearance of the product, and when it is used as a part of a printing machine or a copying machine, the paper feeding becomes unsatisfactory. Further, when it is used for a housing of an electronic device or a tray used in a factory, problems such as malfunction of electronic parts, defective recording of magnetic tape, and destruction of IC element occur.

As a method of antistaticizing a polycarbonate resin, a method of kneading or applying a surfactant into the resin, a method of kneading a conductive filler, a method of kneading a hydrophilic polymer and the like are known. The method of kneading or applying a surfactant to the polycarbonate resin has a problem that the antistatic effect is inferior in sustainability and the effect is remarkably reduced by washing with water. On the other hand, the polycarbonate resin composition containing a conductive filler such as carbon black, carbon fiber, and metal fiber can maintain the antistatic property permanently, but on the other hand, it becomes difficult to reduce the surface property and coloring, and has a transparency. There are problems such as being lost. On the other hand, as a method of kneading a hydrophilic polymer, JP-A-1-163252 discloses a composition comprising a polycarbonate, a polyether ester amide, a vinyl copolymer containing a polar group, and a specific graft copolymer. In addition, JP-A-5-437
No. 87 discloses a composition containing a polycarbonate, a polyamide-polyether block copolymer, and a phosphite or a phenol compound. These are advantageous in that they have excellent durability of antistatic effect, good surface properties, and easy coloring. However, there is a problem that the original excellent transparency of the polycarbonate is lost, the hydrophilic polymer is decomposed in the kneading stage, or the polycarbonate reacts with the polycarbonate to reduce the molecular weight of the polycarbonate and thus the impact strength. As described above, there is a demand for a novel polycarbonate resin composition which has no significant decrease in transparency or impact resistance and has permanent antistatic properties.

[0004]

The object of the present invention is to obtain excellent heat resistance, transparency, and
An object of the present invention is to provide a polycarbonate resin composition having a permanent antistatic property without significantly impairing mechanical properties.

[0005]

The objects of the present invention are: Polycarbonate resin 80 to 99 parts by weight B. Crosslinked polyethylene oxide 0.5 to 20 parts by weight C.I. It is achieved by a composition containing 0.01 to 3.0 parts by weight of at least one electrolyte selected from an organic electrolyte and an inorganic electrolyte.

Hereinafter, the present invention will be described in detail. A. Polycarbonate resin Polycarbonate resin used in the present invention (hereinafter, PC
Abbreviated) is a thermoplastic aromatic polycarbonate polymer made by reacting an aromatic hydroxy compound or a small amount of this polyhydroxy compound with phosgene or a diester of carbonic acid.

The aromatic dihydroxy compound is 2,
2-bis (4-hydroxyphenyl) propane (= bisphenol A), tetramethylbisphenol A, tetrabromobisphenol A, bis (4-hydroxyphenyl) -p-diisopropylbenzene, hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl , Bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) ketone, 1,1-bis (4
-Hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) cyclohexane and the like, particularly bisphenol A from the viewpoint of heat resistance, mechanical strength, moldability and the like.
Is preferred. These dihydroxy compounds may be used alone or as a mixture of two or more kinds.

Thermoplastic resins such as bisphenol-type polyarylate, polyethylene terephthalate, 6,6-nylon, 6-nylon, 6-10-nylon, etc. are mixed with these polycarbonate-based resins within a range that does not impair the effects of the present invention. May be. These polycarbonate resins are
80 to 99% in the composition of the present invention, preferably 90 to 9
Contains 8%. If the content is more than this range, the antistatic effect is reduced, and if it is less than this range, the mechanical properties, heat resistance, and transparency are reduced. The degree of polymerization is not particularly limited, but preferably MI = 1 to 3 in terms of melt index.
0, and more preferably MI = 4 to 10. If the melt index is lower than this range, the moldability will decrease,
If it is higher than this range, the impact strength will decrease.

B. Polyethylene oxide cross-linked product The polyethylene oxide cross-linked product used in the present invention may be any one as long as it has a structure in which polyethylene oxide molecules are chemically bonded in a network form. Such a polyethylene oxide crosslinked product is, for example, 2- (2-
Starting from 2- (2-methoxyethoxy) ethyl glycidyl ether produced by the reaction of (methoxyethoxy) ethanol with epichlorohydrin, this is subjected to ring-opening polymerization to form polyethylene oxide (poly [2- (2methoxyethoxy) ethyl glycidyl ether]), and then reacted with a crosslinking agent such as toluidine diisocyanate.
The cross-linking density of such a polyethylene oxide cross-linked product is not particularly limited, but for the purpose of improving miscibility with polycarbonate, a cross-linking density that allows fluidization at the kneading temperature is preferable, and specifically, the melt index is 0. Those having a fluidity of about 0.1 to 40, more preferably about 0.5 to 20 are preferable. The content of the crosslinked polyethylene oxide is 0.5 to 20 parts by weight, preferably 2 to 10 parts by weight. If the content is higher than this range, the impact strength will decrease, and if the content is lower than this range, the antistatic effect will decrease.

C. At least one electrolyte selected from organic electrolyte and inorganic electrolyte The organic electrolyte used in the present invention includes an organic compound having an acidic group or a metal salt thereof, an organic ammonium salt, an organic phosphonium salt, or the like. As the organic compound having this acidic group or the metal salt thereof,
For example, organic carboxylic acids such as dodecylbenzene sulfonic acid, p-toluene sulfonic acid, dodecyl diphenyl ether disulfonic acid, naphthalene sulfonic acid, stearic acid, lauric acid and polyacrylic acid, and organic phosphoric acid such as diphenyl phosphite and diphenyl phosphate. Examples thereof include alkali metal salts and alkaline earth metal salts. Preferred are salts of organic acids with alkali metals and alkaline earth metals, and among these, salts of sodium, potassium, lithium, magnesium and calcium are preferred from the viewpoint of antistatic effect.

Examples of the organic ammonium salt include quaternary ammonium salts such as trimethyloctylammonium bromide, trimethylammonium chloride and cetyltrimethylammonium chloride, and examples of the organic phosphonium salt include amyltriphenylphosphonium bromide and tetrabutylphosphonium bromide. And other quaternary phosphonium salts.

On the other hand, as the inorganic electrolyte, CaCl ₂ ,
Ca (No ₃ ) ₂ , FeCl ₂ , KBr, KNO ₃ , L
Examples thereof include iCl, MgCl ₂ , NH ₄ Cl, NaNO ₃ . The amount of these electrolytes added is 0.01 to 3 parts by weight, preferably 0.1 to 2 parts by weight. If it is less than this range, a sufficient antistatic effect cannot be obtained, and if it is more than this range, problems such as reduction of impact strength, corrosion of mold, and poor appearance occur.

The composition of the present invention is produced by, for example, uniformly mixing the components using a Henschel mixer, ribbon blender, V-type blender, etc., and then kneading with a single-screw or twin-screw extruder, kneader-type kneader, etc. It can be implemented.

The molded product of the present invention can be obtained by melt-molding this composition. The method of melt molding is not particularly limited, and it can be performed according to a molding processing method generally applied to thermoplastic resins. For example, injection molding, hollow molding, sheet molding, laminated molding, press molding, etc. can be applied, and injection molding is preferable.

Inorganic fillers such as glass fiber, carbon fiber, aramid fiber, talc, mica, calcium carbonate and the like can be added to the composition and molded article of the present invention within a range not impairing the object of the invention. Further, additives such as flame retardants, plasticizers and antioxidants may be added.

[0016]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.・ Materials used (1) Polycarbonate resin Sumitomo Dow Caliber 200-4 (melt index 4) (2) Polyethylene oxide cross-linked product Sumitomo Seika Aquacork TR (3) Electrolyte sodium dodecylbenzenesulfonate (Wako Pure Chemical Industries, Ltd.) Sodium acetate (manufactured by Wako Pure Chemical Industries) Lithium chloride (manufactured by Wako Pure Chemical Industries, Ltd.) (4) Polyamide-polyether copolymer Sanyo Kasei Pelestat 6321 ・ Melting and kneading A cylinder using a Japan Steel Works twin-screw extruder (TEX30HSST type) Melt kneading was performed at a temperature of 260 degrees. Also,
The treatment amount was 10 kg / hr.・ Injection molding Using an injection molding machine (SAV-60-52 type) manufactured by Yamashiro Seiki, the cylinder temperature is 240 degrees, and the injection pressure is 50 kg / c.
Molding was performed at m ² , injection speed of 50%, and mold temperature of 100 degrees. -Measurement of physical properties Bending strength / modulus of elasticity Measured at 23 degrees using an autograph manufactured by Shimadzu according to JIS K7203. Impact strength Measured with a notch according to JIS K7110. Heat distortion temperature It was measured according to ASTM D648. Surface resistance According to JIS K6911, after molding, the sample was conditioned for 72 hours at 23 degrees and 50% RH (before washing with water), and after molding, it was immersed in running water for 10 minutes to wipe off surface moisture. 72 hours, 23 degrees,
Both the samples conditioned under the condition of 50% RH (after washing with water) were measured. Light transmittance Based on JIS K7103, it measured using the Suga Test Instruments haze meter.

Example 1 Polycarbonate (Sumitomo Dow Caliber 20) previously dried at 120 ° C. for 6 hours
0-4) 3.8 kg and 3.8 kg of polyethylene oxide cross-linked product previously vacuum dried at 40 ° C. (manufactured by Sumitomo Seika)
0.2 kg of aqua coke TR) and 0.02 kg of sodium dodecylbenzenesulfonate (manufactured by Wako Pure Chemical Industries, Ltd.) were sufficiently mixed with a Henschel mixer, and then melt-kneaded at 260 degrees using a twin-screw extruder. 70 pellets obtained
After vacuum drying for 24 hours at a temperature, injection molding was performed, and the physical properties were measured. Table 2 shows the results.

(Examples 2 to 4) The same operation as in Example 1 was carried out except that the mixing ratio of the polycarbonate and the polyethylene oxide crosslinked product was changed to the ratio shown in Table 1. Table 2 shows the results.

(Examples 5 and 6) The same operation as in Example 1 was carried out except that the electrolyte shown in Table 1 was used. Table 2 shows the results.

Comparative Examples 1 and 2 The same operations as in Examples 1 and 2 were carried out except that a polyamide-polyether copolymer was used in place of the polyethylene oxide crosslinked product. Table 2 shows the results.

[0021]

[Table 1]

[0022]

[Table 2]

As can be seen from Table 2, the compositions of Examples have higher impact strength and higher transparency than the compositions of Comparative Example 1. Further, no significant increase in surface resistance was observed even after washing with water, indicating that the antistatic effect is excellent in sustainability.

[0024]

Industrial Applicability According to the present invention, it is possible to provide a polycarbonate resin composition having excellent mechanical properties and transparency and having a permanent antistatic property. The composition of the present invention and the molded product thereof are useful as materials and members in the field of electronic devices and the like by utilizing such characteristics.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C08L 75:04)

Claims (2)

[Claims] 1. A. Polycarbonate resin 80 to 99 parts by weight B. Crosslinked polyethylene oxide 0.5 to 20 parts by weight C.I. A resin composition excellent in antistatic properties, which comprises 0.01 to 3.0 parts by weight of at least one electrolyte selected from organic electrolytes and inorganic electrolytes. 2. A molded product obtained by melt-molding the resin composition having excellent antistatic properties according to claim 1.