JP5825926B2 - Polycarbonate resin composition - Google Patents

Description

  The present invention relates to a polycarbonate resin composition capable of obtaining a molded product having a matte appearance and high strength, and a molded product formed by molding the polycarbonate resin composition.

Polycarbonate resins are excellent in impact resistance, heat resistance, and transparency, and are widely used in various fields such as electric / electronic, optical, building materials, medical, food, and vehicles.
The polycarbonate resin is often used for a plate-shaped molded article having a smooth surface or a mirror-finished molded article for optics due to its excellent transparency. On the other hand, when the surface is a mirror surface, the light transmittance is high, but the reflected light becomes strong at the position of the regular reflection direction from the light source, which may cause glare. For example, in the case of outdoor building materials, the reflected light becomes too dazzling, which may cause practical problems.

Conventionally, as a method for obtaining a matte appearance, a method of forming irregularities on the surface with an embossing roll and a method of providing fine irregularities on the inner surface of an injection mold are proposed. However, there is a problem that the production efficiency as a whole deteriorates because it is necessary to deal with equipment such as replacement of rolls and molds when switching to molding of a mirror surface molded product.
In addition, there is a method of obtaining a matte appearance by coating, but there is a problem that dust and the like are easily adsorbed during coating and the cost is increased.

  On the other hand, as a technique for modifying the resin itself, a method of dispersing fine particles in a thermoplastic resin (Japanese Patent Laid-Open No. Sho 63-137911) has been proposed. There was a problem of lowering.

  Further, a method has been proposed in which a material in which fine particles are dispersed in a resin is used as a surface layer, and this is integrally formed with a base material (Japanese Patent Laid-Open No. 3-558840). Multi-layer extrusion equipment and injection molding require a two-color molding machine and a two-color mold, leading to an increase in cost.

JP-A 63-137911 JP-A-3-558840

  In particular, in applications such as electrical and electronic cases, games, and amusement-related parts, resin materials having high strength and matting properties are desired.

  An object of this invention is to provide the polycarbonate resin composition which can obtain the molded article which has a matt appearance and has high intensity | strength, and the molded article formed by shape | molding this.

  As a result of intensive studies to solve the above problems, the present inventors have obtained a polycarbonate resin composition excellent in not only matteness but also strength by using organic polymer particles and an elastomer together in a polycarbonate resin. As a result, the present invention was completed.

That is, the present invention is a polycarbonate resin composition comprising 100 parts by weight of a polycarbonate resin (A), 0.5 to 10 parts by weight of organic polymer particles (B) and 0.5 to 10 parts by weight of an elastomer (C). Using a test piece having a thickness of 2 mm obtained by injection molding the composition, the gloss measured at a measurement angle of 60 degrees based on JIS K7105 is 80% or less, and the elastomer (C) is epoxy-modified. acrylic elastomer der is, the organic polymer particles (B), one or more of the polymer particles is selected acrylic polymer particles, silicone polymer particles, a styrene polymer particles The present invention relates to a polycarbonate resin composition and a molded article obtained by molding the polycarbonate resin composition.

  Since the polycarbonate resin composition of the present invention can obtain a matte appearance without impairing the excellent strength inherent in the polycarbonate resin, matting is required as a member or design property that impairs its function by mirror reflection. It is also suitable for the construction field such as electrical and electronic housings, exteriors of game / amusement related equipment, and partitions. In particular, it is suitably used as a peripheral member of game / amusement related equipment that requires high impact and matte properties.

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

  Examples of the dihydroxydiaryl compound include bisphenol 4-, 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-hydroxyphenyl-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3) -Tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis ( Bis (hydroxyaryl) alkanes such as 4-hydroxy-3,5-dichlorophenyl) propane, 1,1- (4-hydroxyphenyl) cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3 Dihydroxy diaryl ethers such as 3,3'-dimethyldiphenyl ether, dihydroxy diaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3 ' Dihydroxy diaryl sulfoxides such as dimethyldiphenyl sulfoxide, dihydroxy diary such as 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone Sulfone, and the like. These are used individually or in mixture of 2 or more types. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4'-dihydroxydiphenyl, and the like may be mixed and used.

  Furthermore, the above dihydroxyaryl compound and a trivalent or higher phenol compound as shown below may be used in combination. Trihydric or higher phenols include phloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene, 2,4,6-dimethyl-2,4,6-tri- (4 -Hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -ethane and 2,2-bis- [4 4- (4,4'-dihydroxydiphenyl) -cyclohexyl] -propane and the like.

  The viscosity average molecular weight of the polycarbonate resin is usually 10,000 to 100,000, preferably 15,000 to 35,000, and more preferably 17,000 to 28,000. In producing such a polycarbonate resin, a molecular weight regulator, a catalyst and the like can be used as necessary.

  As the organic polymer particles (B) used in the present invention, those showing a spherical form can be suitably used. Examples of the organic polymer particles having a spherical shape include particles of silicone polymers and acrylic polymers. The average particle diameter of the organic polymer particles (B) is preferably in the range of 1 to 30 μm. Examples of silicone polymer particles include Tospearl 120S manufactured by Momentive Japan, and examples of acrylic polymer particles include Gantz Pearl GM0449S manufactured by Ganz Kasei Co., Ltd. and Chemisnow KMR-3TA manufactured by Soken Chemical Co., Ltd.

The addition amount of the organic polymer particles (B) is 0.5 to 10 parts by weight per 100 parts by weight of the polycarbonate resin (A). If the addition amount is less than 0.5 parts by weight, the matte effect of the polycarbonate resin cannot be sufficiently obtained, and if it exceeds 10 parts by weight, the impact strength is lowered, which is not preferable. More preferably, it is in the range of 2 to 8 parts by weight.

  Examples of the elastomer (C) used in the present invention include MBS resin, MAS resin, and acrylic resin. In particular, an epoxy-modified acrylic resin can be suitably used for maintaining the impact strength.

The addition amount of the elastomer (C) is 0.5 to 10 parts by weight per 100 parts by weight of the polycarbonate resin (A). If the addition amount is less than 0.5 parts by weight, the impact strength maintenance effect of the polycarbonate resin cannot be sufficiently obtained, and if it exceeds 10 parts by weight, the thermal stability is deteriorated, which is not preferable. More preferably, it is in the range of 2 to 8 parts by weight.

  The polycarbonate resin composition of the present invention can be added with various known additives, polymers and the like, if necessary. For example, a hindered amine light-resistant stabilizer can be added to suppress discoloration of a resin molded product when exposed to light for a long period of time, and a benzoxazole-based fluorescent whitening agent can be added to obtain a vivid color tone. Good. Further, these may be added in combination.

  In the polycarbonate resin composition of the present invention, known additives other than those described above, for example, phenol-based or phosphorus-based heat stabilizer [2,6-di-t-butyl-4-methylphenol, 2- (1-methylcyclohexyl) ) -4,6-dimethylphenol, 4,4'-thiobis- (6-tert-butyl-3-methylphenol), 2,2-methylenebis- (4-ethyl-6-tert-methylphenol), n- Octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, tris (2,4-di-t-butylphenyl) phosphite, 4,4'-biphenylenediphosphinic acid tetrakis- (2 , 4-di-t-butylphenyl), etc.], lubricants [paraffin wax, n-butyl stearate, synthetic beeswax, natural beeswax, glycerin monoester, Tanic acid wax, polyethylene wax, pentaerythritol tetrastearate, etc.], colorant [eg titanium oxide, carbon black, dye], filler [calcium carbonate, clay, silica, glass fiber, glass sphere, glass flake, carbon fiber, Talc, mica, various whiskers, etc.], fluidity improver, spreading agent [epoxidized soybean oil, liquid paraffin, etc.] can be added as necessary.

  There is no restriction | limiting about the addition order of the various compounding components in this invention. For example, polycarbonate resin (A), organic polymer particles (B) and elastomer (C) are weighed in arbitrary amounts and mixed together with a tumbler, ribbon blender, high speed mixer, etc., and then the mixture is subjected to normal single screw extrusion. A method of melt-kneading and pelletizing using a machine or a twin-screw extruder, or a method of weighing each or all of individual components separately, putting them into a extruder from a plurality of supply devices, and melt-mixing, Further, (A) and (C) and / or (B) are blended at a high concentration, once melt-mixed and pelletized to obtain a master batch, and then the master batch and the polycarbonate resin (A) are obtained in a desired manner. It can also be mixed in proportions. Then, when these components are melt-mixed, arbitrary conditions such as the position to be fed into the extruder, the extrusion temperature, the screw rotation speed, and the supply amount can be selected and pelletized. Further, the master batch and the polycarbonate resin (A) can be dry-mixed at a desired ratio, and then directly fed into an injection molding device or a sheet extruder device to form a molded product.

  EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited to these examples. Unless otherwise specified, “%” and “part” in the examples are based on weight standards.

The raw materials used are as follows.
Polycarbonate resin (A):
Polycarbonate resin synthesized from bisphenol A and phosgene (Caliber 200-13, manufactured by Sumika Stylon Polycarbonate)
Viscosity average molecular weight: 21500, hereinafter abbreviated as “PC”)
Organic polymer particles (B):
GM-0449S manufactured by Gantz Kasei
(Acrylic polymer particles, hereinafter abbreviated as “Particle 1”)
Mostive Japan Tospearl 120S
(Polymethylsilsesquioxane polymer particles, hereinafter abbreviated as “Particle 2”)
Elastomer (C):
Rohm and Haas Paraloid EXL-2314
(Epoxy-modified acrylic elastomer, hereinafter abbreviated as “EL1”)
Rohm and Haas Paraloid EXL-2602
(MBS elastomer, hereinafter abbreviated as “EL2”)

Each of the above-mentioned various raw materials was put in a tumbler at the blending ratios shown in Tables 1 to 3, and after dry mixing for 10 minutes, a twin screw extruder (TEX30α (L / D = 42, Φ = 30 mm, manufactured by Nippon Steel) )) And kneaded at a melting temperature of 260 ° C. to obtain pellets.
Using the obtained pellets, under a condition of 290 ° C., an injection molding machine (J100EII-P, manufactured by Nippon Steel Works), 50 mm wide × 90 mm long three-stage plate-shaped test piece (3 mm portion: width 50 mm × length 35 mm / 2 mm) Part: width 50 mm × length 30 mm / 1 mm part: width 50 mm × length 25 mm).
Using the obtained pellets, an Izod impact test piece having a width of 12.7 mm, a length of 63.5 mm, and a thickness of 3.2 mm on an injection molding machine (J100EII-P manufactured by Nippon Steel) under the same conditions at 290 ° C. It was created. The prepared Izod impact test piece was notched by a milling machine according to D-256.

Various evaluation items and measurement methods in the present invention will be described.
1. Impact strength:
Using the obtained Izod impact test piece, the notched Izod impact strength was measured in accordance with ASTM D-256. At a thickness of 3.2 mm, 50 kg · cm / cm or more was accepted.
2. Matte properties:
Using the obtained three-stage plate-like test piece, the gloss at a measurement angle of 60 degrees was measured according to JIS K7105. 80% or less at 2 mm thickness was regarded as acceptable.
3. Yellowness index (YI)
Using the obtained three-stage plate-like test piece, the yellowness index (YI) of the 2 mm portion was measured according to ASTM D-1925. A YI of 20 or less was accepted.
4). Light transmittance The light transmittance at a 2 mm portion of the test piece was measured based on JIS K7361.

  As shown in Tables 1 and 2, when the polycarbonate resin composition satisfies the requirements of the present invention (Examples 1 to 12), the required performances of impact strength, gloss and YI all satisfy the required levels. It was.

On the other hand, as shown in Table 3, when the configuration of the present invention was not satisfied, each case had some drawbacks.
Comparative Example 1 was a case where the blending amount of the organic polymer particles was less than the specified amount, and the gloss was inferior.
Comparative Example 2 was a case where the blending amount of the organic polymer particles was larger than the specified amount, and the impact strength was inferior.
In Comparative Example 3 and Comparative Example 5, the amount of the elastomer was less than the specified amount, and the impact strength was inferior.
Comparative Example 4 and Comparative Example 6 were cases where the blending amount of the elastomer was larger than the specified amount, and YI was inferior.

Claims (2)

A polycarbonate resin composition comprising 100 parts by weight of a polycarbonate resin (A), 0.5 to 10 parts by weight of organic polymer particles (B) and 0.5 to 10 parts by weight of an elastomer (C), wherein the composition is injected. Using a test piece having a thickness of 2 mm obtained by molding, the glossiness measured at a measurement angle of 60 degrees based on JIS K7105 is 80% or less, and the elastomer (C) is an epoxy-modified acrylic elastomer. Ah it is, the organic polymer particles (B), and characterized in that the one or more polymer particles are selected acrylic polymer particles, silicone polymer particles, a styrene polymer particles A polycarbonate resin composition. Molded article obtained by molding the polycarbonate resin composition of claim 1 Symbol placement.