JP2924005B2 - Scratch-resistant polycarbonate resin composition - Google Patents

Description

The present invention relates to a resin composition in which an aromatic polycarbonate resin is blended with a specific semi-aromatic polyamide resin and a thermoplastic polyester resin. More specifically, the present invention relates to an aromatic polycarbonate resin composition having high mechanical strength and excellent scratch resistance.

[Conventional technology]

Aromatic polycarbonate resins have excellent mechanical properties, heat resistance, and dimensional stability, and are therefore used in a wide range of fields such as industrial equipment, home appliances, and camera parts. Among them, OA equipment housing and camera body,
In toiletries and the like, products having high commercial value have been obtained by utilizing the beautiful appearance of the aromatic polycarbonate resin.

Aromatic polycarbonate resin is excellent in such mechanical properties and heat resistance, and has an excellent appearance and a beautiful surface gloss, but is inferior in scratch resistance due to low surface hardness and is wiped off with a cloth. If it is handled rough or rough, the surface is easily damaged and the commercial value is significantly reduced.

[Problems to be solved by the present invention]

For this reason, it is performed to form a film having a high surface hardness on the surface of the product using the aromatic polycarbonate resin. For example, a silicone resin-based or acrylic resin-based coating agent is applied. However, there are difficulties in the adhesion of the coating film, it is difficult to coat a product having a complicated shape, and the price is expensive. In addition, it is also practiced to paint on the product surface, but as with coating, it is difficult to obtain a uniform coating film depending on the product shape, and because of the use of thinner, solvent deterioration of the polycarbonate resin If the coating film thickness is not large, the effect of improving the surface hardness is low.

Therefore, it has been desired to improve the hardness of the aromatic polycarbonate resin itself to increase the scratch resistance,
For example, even when an inorganic material having a high hardness is blended, the abrasion resistance of the aromatic polycarbonate resin is slightly improved, and a favorable appearance is easily impaired, and the original properties of the aromatic polycarbonate resin are lost. Therefore, the fact is that aromatic polycarbonate resins having high scratch resistance have not been industrially obtained.

[Means for solving the problem]

The present inventors have conducted intensive studies to improve the scratch resistance while maintaining the mechanical and thermal properties of the aromatic polycarbonate resin, and the excellent appearance and dimensional properties. When a specific semi-aromatic polyamide resin and a polyalkylene terephthalate-based thermoplastic polyester resin are blended with the aromatic polycarbonate resin, the scratch resistance is greatly improved, and further improvement can be made by further blending an inorganic filler. It was found that.

That is, the gist of the present invention is as follows: (I) 40 to 90% by weight of an aromatic polycarbonate resin [II] (a) 100 to 60% by weight of a polyamide forming unit comprising an aliphatic diamine and isophthalic acid and terephthalic acid,
And (b) a semi-aromatic polyamide resin composed of 0 to 40% by weight of a polyamide-forming unit composed of a lactam and / or an aliphatic diamine and an aliphatic dicarboxylic acid, 5 to 50% by weight [III] polyalkylene terephthalate or mainly composed thereof A scratch-resistant polycarbonate resin composition comprising 3 to 30% by weight of a thermoplastic polyester resin comprising a copolymer represented by the following formula: and an inorganic material containing 10% by weight or more of glass fiber with respect to 100 parts by weight of the composition. A polycarbonate resin composition containing 5 to 120 parts by weight of a filler.

Is provided.

Although the reason why the composition of the present invention exhibits excellent scratch resistance is not clear, the semi-aromatic polyamide resin is a material having a strong resilience to scratches, and it is easy to selectively form a thin surface layer on the surface of a molded product. It seems to be because. However, it is known that when a material having a so-called amide bond is blended with an aromatic polycarbonate resin, the polycarbonate is likely to undergo molecular breakage and is inferior in thermal stability, and a semi-aromatic polyamide resin is no exception. However, when the thermoplastic polyester resin is mixed at the same time, the deterioration of the aromatic polycarbonate resin is suppressed, and the thermal stability during melt processing is significantly improved. On the other hand, when the thermoplastic polyester resin is blended with the aromatic polycarbonate resin, the heat exchange and the moldability are reduced due to the transesterification of the two resins, and the crystallization of the thermoplastic polyester resin is hindered. Since the crystal structure is easily formed, the scratch resistance is also reduced.
However, when a polyalkylene terephthalate-based thermoplastic polyester resin and a semi-aromatic polyamide resin are simultaneously compounded with an aromatic polycarbonate resin, the above-mentioned disadvantages are solved, the scratch resistance is improved, and the heat resistance and moldability are reduced. I can't see it either.

Further, by incorporating an inorganic filler having a high surface hardness, the scratch resistance is further improved. Particularly in the case of an aromatic polycarbonate resin, usually when carbon black is blended and colored, the scratched part loses gloss and whitens, so that the glossiness is significantly impaired and the commercial value is reduced, In the case of the composition, even when carbon black is blended, the aromatic polyamide resin having good colorability of carbon black is selectively present in a large amount on the surface layer, so that even if the surface layer is scratched, the gloss is reduced. It is thought that the effect of maintaining high commercial value is low.

 Hereinafter, the present invention will be described specifically.

The aromatic polycarbonate resin [I] used in the present invention is obtained by a phosgene method in which various dihydroxydiaryl compounds are reacted with phosgene, or a transesterification method in which a dihydroxydiaryl compound is reacted with a carbonate such as diphenyl carbonate. A typical example is a polycarbonate resin produced from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).

Examples of the dihydroxydiaryl compound include bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane,
2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-
(Hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis Bis (hydroxyaryl) alkanes such as (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 1,1-bis (4- (Hydroxyphenyl) cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3 ′
Dihydroxy diaryl ethers such as dimethyl diphenyl ether, 4,4'-dihydroxy diphenyl sulfide, dihydroxy diaryl sulfides such as 4,4'-dihydroxy-3,3'-dimethyl diphenyl sulfide, 4,4'-dihydroxy Dihydroxysulfoxides such as diphenylsulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone And dihydroxydiarylsulfonic acids.

These are used alone or in combination of two or more,
In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4'-dihydroxydiphenyl, and the like may be used as a mixture.

The semi-aromatic polyamide resin [II] used in the present invention refers to a polyamide-forming unit (a) composed of an aliphatic diamine and an aromatic dicarboxylic acid composed of isophthalic acid and terephthalic acid (a) 100 to 60% by weight, and a lactam And / or a polymer or copolymer comprising 0 to 40% by weight of a polyamide-forming unit (b) comprising an aliphatic diamine and an aliphatic dicarboxylic acid.

Here, the aliphatic diamine used for the polyamide-forming unit (a) containing an aromatic dicarboxylic acid includes linear aliphatic diamines such as ethylenediamine, tetramethylenediamine, hexamethylenediamine, octamethylenediamine, and decamethylenediamine. And its methylation,
Derivatives such as ethylation and halides, and bis-
An aliphatic diamine containing a cyclohexane ring such as (3-methyl-4-aminocyclohexyl) methane may be partially contained. Among them, the use of hexamethylenediamine is desirable. Isophthalic acid and terephthalic acid used as aromatic dicarboxylic acids may be used in any ratio, but preferably isophthalic acid / terephthalic acid = 80.
/ 20 to 20/80 (weight ratio).

Examples of the lactam used in the polyamide-forming unit (b) comprising a lactam and / or an aliphatic diamine and an aliphatic dicarboxylic acid include caprolactam, lauryl lactam, butyrolactam, caprylactam, enantholactam, undecanolactam, and dodecanolactam. And the like. As for aliphatic diamines, ethylenediamine, tetramethylenediamine, hexamethylenediamine, octamethylenediamine, linear aliphatic diamines such as decamethylenediamine, and aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, Pimelic acid, suberic acid, azelaic acid, sebacic acid and derivatives thereof such as methylated, ethylated, and halide thereof. Among them, polyamide-forming units obtained from caprolactam and / or hexamethylenediamine and adipic acid, and composed of so-called nylon 6 and / or nylon 66 give preferable results.

As a method for producing such a semi-aromatic polyamide resin, usually, a nylon salt comprising a diamine and a dicarboxylic acid or an aqueous solution thereof is added with a lactam as needed, and the production is carried out by a so-called melt polymerization method, and isophthalic acid and terephthalic acid are used. Is produced by a solution method or an interfacial method, depending on the composition.

The thermoplastic polyester resin [III] used in the present invention is a polyalkylene terephthalate obtained by a polycondensation reaction of terephthalic acid or a dialkyl ester thereof with an aliphatic glycol, or a copolymer containing these as a main component. Typical examples include polyethylene terephthalate and polybutylene terephthalate.

Examples of the aliphatic glycols include ethylene glycol, propylene glycol, tetramethylene glycol, and the like, and together with these aliphatic glycols, other diols or polyhydric alcohols, for example, cyclohexanediol with respect to the aliphatic glycols , Cyclohexanedimethanol, xylylene glycol, 2,2
-Bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxyethoxyphenyl) propane, 2,2-bis ( 4-Hydroxyethoxy-3,5-dibromophenyl) propane, glycerin, pentaerythritol and the like may be mixed and used.

Also, for terephthalic acid or dialkyl esters thereof, together with them, other dibasic acids, polybasic acids or alkyl esters thereof, for example, phthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, adipic acid, sebacic acid, Trimesic acid, trimellitic acid, and their alkyl esters may be used as a mixture.

The mixing ratio of the aromatic polycarbonate resin to the semi-aromatic polyamide resin and the thermoplastic polyester resin is as follows: [I] 40 to 90% by weight of the aromatic polycarbonate resin [II] 5 to 50% by weight of the semi-aromatic polyamide resin [III] The thermoplastic polyester resin is selected in the range of 3 to 30% by weight. If the amount of the semi-aromatic polyamide resin is less than 5% by weight, the effect of improving the scratch resistance is insufficient, and if it exceeds 50% by weight, the dimensional stability and the thermal stability at the time of melt processing are reduced. Absent. If the amount of the thermoplastic polyester is less than 3% by weight, the heat stability during melt processing is poor, and if it exceeds 30 parts by weight, the effect of improving the scratch resistance becomes insufficient.

In the present invention, 5 to 120 parts by weight of an inorganic filler containing glass fiber can be further added to 100 parts by weight of the total of [I], [II], and [III]. The inorganic filler contains glass fiber at 10% by weight or more. It may consist of glass fiber only, but if necessary, glass flakes, glass beads, talc, calcium carbonate,
One or more inorganic fillers selected from wollastonite, carbon fiber, and calcium carbonate can be used in combination. As the glass fiber used as a main component, a normal glass fiber commercially available for reinforcing a thermoplastic resin is used, but there is no particular limitation on the fiber diameter and length, and any of roving, chopped strand, and milled fiber is used. Can also be used. Among them, a good appearance can be obtained by using a common chopped strand together with milled fiber.

Further, the composition of the present invention, in addition to the above-mentioned formulation,
Well-known various additives, for example, a hydrolysis inhibitor such as an epoxy compound, a paraffin wax, a lubricant such as a fatty acid ester, a hindered phenol, an antioxidant such as a phosphoric acid ester or a phosphite, a triazine-based compound or the like Weather resistance improver, carbon black and other pigments,
A coloring agent such as a dye, a flame retardant, an antistatic agent and the like may be contained. Further, the composition of the present invention may be used by mixing other resin materials as long as the effects of the present invention are not impaired.

〔Example〕

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples at all without departing from the gist thereof.

Reference Example 1: Production method of semi-aromatic polyamide 90% aqueous solution of hexamethylenediamine 2.28 kg water 9.0 kg isophthalic acid 1.96 kg terephthalic acid 0.98 kg After sufficient replacement with
The pressure was raised to kg / cm ² , then the temperature was raised to 250 ° C. while adjusting the pressure to be constant, and polymerization was carried out with stirring. Five hours later, the pressure was gradually released, and the pressure was further reduced to 700 mmHg. Thereafter, the pressure was returned to normal pressure, and the polymerized resin was extracted. This resin was a polyamide resin containing 100% by weight of a polyamide-forming component composed of an aliphatic diamine, isophthalic acid and terephthalic acid, and had a relative viscosity of 2.1.

Reference Example 2: Manufacturing method of semi-aromatic polyamide 90% aqueous solution of hexamethylenediamine 2.28 kg water 9.0 kg isophthalic acid 1.96 kg terephthalic acid 0.98 kg caprolactam 0.71 kg After charging and sufficiently replacing with nitrogen, the pressure in the tank was increased to 18
The pressure was raised to kg / cm ² , then the temperature was raised to 250 ° C. while adjusting the pressure to be constant, and polymerization was carried out with stirring. Five hours later, the pressure was gradually released, and the pressure was further reduced to 700 mmHg. Thereafter, the pressure was returned to normal pressure, and the polymerized resin was extracted. This resin has a polyamide-forming component composed of an aliphatic diamine and isophthalic acid and terephthalic acid at 85% by weight,
The polyamide forming component consisting of the lactam component was a polyamide resin of 15% by weight, and the relative viscosity was 2.0.

Examples 1 to 8 and Comparative Examples 1 to 5 As aromatic polycarbonate resin [I], a commercially available bisphenol A-type polycarbonate resin having a solution molecular weight of 22,000 (manufactured by Mitsubishi Chemical Corporation, trade name: NOVAREX 7022A), semi-aromatic polyamide Resin [II] obtained in Reference Examples 1 and 2 and, for comparison, a commercially available nylon 6 resin having a relative viscosity of 2.5 (manufactured by Mitsubishi Kasei Corporation, trade name: NOVAMID 1010)
C), commercially available polybutylene terephthalate resin (manufactured by Mitsubishi Kasei Corporation, trade name: NOVADUR 5010) as a thermoplastic polyester resin [III], polyethylene terephthalate resin (manufactured by Nippon Unipet Co., Ltd., trade name: RT543C), And commercially available chopped fiber (manufactured by Asahi Fiber Glass Co., Ltd., trade name: 486A) and milled fiber (manufactured by Asahi Fiber Glass Co., trade name: MF-
A), using commercially available carbon black (manufactured by Mitsubishi Kasei Co., Ltd., trade name: diamond black # 1000) with the composition shown in Table 1, and then using a vented extruder having a cylinder diameter of 40φ to obtain a resin temperature of 260. The mixture was melt-mixed at 290290 ° C. and pelletized. The pellets thus obtained were dried in an atmosphere at 120 ° C. for 5 hours, and then subjected to an injection molding machine (Toshiba Machine Co., Ltd.) with a mold clamping force of 75 tons.
Test pieces were injection molded at a cylinder temperature of 260 to 270 ° C and a mold temperature of 80 to 100 ° C using IS75PN II). At the time of molding, the compositions of Comparative Examples 2, 4 and 5 were observed to decompose the resin in a molten state, to generate white smoke from the molding machine nozzle, and to generate silver streaks on the test piece surface. The obtained test pieces were subjected to tensile strength, bending strength, Izod impact value, and abrasion resistance test based on the following test methods. The results are shown in Table 2.

(Test method) Tensile strength: Performed according to ASTM D-638.

Izod impact value: ASTM D using 1/2 inch thick test piece
Performed according to -256.

Flexural strength: Performed according to ASTM D-790.

Pencil hardness (surface hardness): Conducted according to JIS K5400.
In the table, H, HB and B indicate the hardness of the pencil having the highest hardness that does not damage the resin.

Scratch resistance test …… Place canvas No.50 on the test piece.
A weight is applied so that the surface load becomes 1 kg / cm ² , and the cloth is reciprocated at a speed of 2 cm / sec.
Based on S Z8741, measured as gloss at an incident angle of 60 degrees,
Changes before and after the test were measured.

[Effect of the Invention] The polycarbonate resin composition of the present invention retains the excellent mechanical properties of the aromatic polycarbonate resin, and has a good surface gloss, high hardness, and excellent scratch resistance. Less decrease in glossiness. Therefore, it is possible to obtain a product having a high commercial value in OA equipment, cameras, toiletries, and the like, since the surface is not easily damaged during use.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ identification code FI C08L 67:02) (58) Investigated field (Int.Cl. ⁶ , DB name) C08L 69/00 C08L 67/00-67 / 08 C08L 77/00-77/12

Claims (2)

(57) [Claims] [I] Aromatic polycarbonate resin: 40 to 9
0% by weight [II] (a) 100 to 60% by weight of polyamide-forming unit composed of aliphatic diamine and isophthalic acid and terephthalic acid, and (b) Polyamide-forming unit composed of lactam and / or aliphatic diamine and aliphatic dicarboxylic acid Semi-aromatic polyamide resin consisting of 0 to 40% by weight of a unit: 5 to 50% by weight [III] Thermoplastic polyester resin consisting of a polyalkylene terephthalate or a copolymer containing the same as a main component: 3 to
A scratch-resistant polycarbonate resin composition comprising 30% by weight. 2. A scratch-resistant polycarbonate resin composition comprising 5 to 120 parts by weight of an inorganic filler containing 10% by weight or more of glass fiber with respect to 100 parts by weight of the composition according to claim 1.