JP2016117849A - Polycarbonate resin composition and resin molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polycarbonate resin composition having both of high surface hardness and good transparency.SOLUTION: A polycarbonate resin composition contains (A) a polycarbonate resin, (B) an acrylic modifier and (C) a graft copolymer. The content of the (B) acrylic modifier is 5 to 60 pts.wt. and the content of the (C) graft copolymer is 0.5 to 20 pts.wt. based on 100 pts.wt. of the total content of the (A) polycarbonate resin and the (B) acrylic modifier. The (C) graft copolymer is constituted by 50 to 80 wt.% of polycarbonate and 20 to 50 wt.% of a polymethacrylic methyl copolymer and the polycarbonate is a main chain and the polymethacrylic methyl copolymer is a side chain. The polymethacrylic methyl copolymer contains 10 wt.% or more of methyl methacrylate.SELECTED DRAWING: None

Description

  The present invention relates to a polycarbonate resin composition having transparency and a resin molded product.

  Polycarbonate resins are thermoplastic resins that are excellent in impact resistance, heat resistance, thermal stability, and the like, and are therefore widely used in casings for electrical and electronic parts, automobile interior materials, and the like. On the other hand, the polycarbonate resin has a drawback that it is easily scratched because of its low surface hardness.

  In order to improve the surface hardness of the polycarbonate resin, a technique for coating the surface of the polycarbonate resin with an ultraviolet curable resin is known. However, in applications that require a high surface hardness such as a display, the inherent flexibility of the polycarbonate resin cannot be overcome even by this technique, and sufficient surface hardness may not be obtained.

  Techniques for further improving the surface hardness of the polycarbonate resin are disclosed in Patent Documents 1 and 2. In the techniques described in Patent Documents 1 and 2, the surface hardness of the polycarbonate resin can be significantly improved by adding an acrylic modifier to the polycarbonate resin.

JP 2009-280713 A JP 2010-116501 A

  For display applications, polycarbonate resins are required to have not only high surface hardness but also good transparency. In the technique using the acrylic modifier described in Patent Documents 1 and 2, a sufficiently high surface hardness can be obtained, but the transparency of the polycarbonate resin is impaired.

  In view of the circumstances as described above, an object of the present invention is to provide a polycarbonate resin composition having a high surface hardness and good transparency, and a resin molded product.

In order to achieve the above object, a polycarbonate resin composition according to one embodiment of the present invention comprises (A) a polycarbonate resin, (B) an acrylic modifier, and (C) a graft copolymer. Yes.
When the total content of the (A) polycarbonate resin and the (B) acrylic modifier is 100 parts by weight, the content of the (B) acrylic modifier is 5 to 60 parts by weight, (C) The content of the graft copolymer is 0.5 to 20 parts by weight.
The (C) graft copolymer is composed of 50 to 80% by weight of polycarbonate and 20 to 50% by weight of polymethyl methacrylate copolymer, the main chain is the polycarbonate, and the side chain is the above. Polymethyl methacrylate copolymer.
The polymethyl methacrylate copolymer contains 10% by weight or more of methyl methacrylate.
With this configuration, a polycarbonate resin composition having both high surface hardness and good transparency can be provided.

The polymethyl methacrylate copolymer may be a copolymer of methyl methacrylate and an aromatic vinyl monomer.
With this configuration, the surface hardness and transparency of the polycarbonate resin composition can be further improved.

The (B) acrylic modifier may be a copolymer of methyl methacrylate and an aromatic vinyl monomer.
With this configuration, the surface hardness of the polycarbonate resin composition can be improved.

  The resin molded product according to an embodiment of the present invention is obtained by molding the polycarbonate resin composition into a predetermined shape.

  A polycarbonate resin composition having both high surface hardness and good transparency, and a resin molded product can be provided.

  Hereinafter, an embodiment of the present invention will be described.

[Polycarbonate resin composition]
The polycarbonate (PC) resin composition according to this embodiment contains (A) a polycarbonate (PC) resin, (B) an acrylic modifier, and (C) a graft copolymer. In this polycarbonate resin composition, the total content of (A) polycarbonate resin and (B) acrylic modifier is 100 parts by weight, and the content of (A) polycarbonate resin is 40 to 95 parts by weight, (B) The content of acrylic modifier is 5 to 60 parts by weight, and the content of (C) graft copolymer is 0.5 to 20 parts by weight.

  In the polycarbonate resin composition according to this embodiment, the mechanical properties of (A) polycarbonate resin are impaired by adding (B) acrylic modifier and (C) graft copolymer to (A) polycarbonate resin. Without any problem, high surface hardness and good transparency can be obtained.

<(A) Polycarbonate resin>
The polycarbonate resin (A) according to this embodiment is produced 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 representative dihydroxydiaryl compound is 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).

  (A) Dihydroxydiaryl compounds that can be used for the production of polycarbonate resins are roughly classified into (1) bis (hydroxyaryl) alkanes, (2) bis (hydroxyaryl) cycloalkanes, and (3) dihydroxydiaryl ethers. (4) dihydroxy diaryl sulfides, (5) dihydroxy diaryl sulfoxides, (6) dihydroxy diaryl sulfones and the like.

More specifically, (1) bis (hydroxyaryl) alkanes include, for example, 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 (4-hydroxy-3,5-dichlorophenyl) propane and the like.
(2) Examples of bis (hydroxyaryl) cycloalkanes include 1,1-bis (4-hydroxyphenyl) cyclopentane and 1,1-bis (4-hydroxyphenyl) cyclohexane.
(3) Examples of dihydroxydiaryl ethers include 4,4′-dihydroxydiphenyl ether and 4,4′-dihydroxy-3,3′-dimethyldiphenyl ether.
(4) Examples of dihydroxydiaryl sulfides include 4,4'-dihydroxydiphenyl sulfide.
(5) Examples of dihydroxydiaryl sulfoxides include 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide, and the like.
(6) Examples of dihydroxydiaryl sulfones include 4,4′-dihydroxydiphenyl sulfone and 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfone.

  The dihydroxydiaryl compound as described above may be composed of a single type or may include a plurality of types. Further, the dihydroxydiaryl compound can be used by mixing with piperazine, dipiperidylhydroquinone, resorcin, 4,4′-dihydroxydiphenyl and the like. Furthermore, the dihydroxyaryl compound can also be used as a mixture with a trivalent or higher valent phenol compound. Examples of the trivalent or higher phenol 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- And [4,4- (4,4'-dihydroxydiphenyl) -cyclohexyl] -propane.

<(B) Acrylic modifier>
As the acrylic modifier (B) according to this embodiment, a known acrylic modifier can be used. (B) The acrylic modifier is preferably a methyl methacrylate (MMA) copolymer that is a copolymer of methyl methacrylate (MMA) and an aromatic vinyl monomer.

  Further, as the methyl methacrylate copolymer, when the total content of methyl methacrylate and aromatic vinyl monomer is 100% by weight, the content of methyl methacrylate is 20 to 95% by weight. The group vinyl monomer content is preferably 5 to 80% by weight.

  By setting the content of the aromatic vinyl monomer to 5% by weight or more, the transparency of the polycarbonate resin composition can be maintained particularly high. Further, by controlling the content of the aromatic vinyl monomer to 80% by weight or less, methyl methacrylate (MMA) necessary for improving the surface hardness can be present on the surface of the polycarbonate resin composition. Therefore, the surface hardness can be improved.

An aromatic (meth) acrylate unit is used as the aromatic vinyl monomer. The aromatic (meth) acrylate unit is, for example, phenyl methacrylate (PhMA) or benzyl methacrylate (BzMA), and is preferably phenyl methacrylate. In the present specification, (meth) acrylate means acrylate or methacrylate.

  (B) The acrylic modifier may contain monomer units of subcomponents other than the main component, if necessary. The subcomponent monomer units are roughly classified into (1) methacrylate, (2) acrylate, (3) vinyl cyanide monomer, (4) diene monomer, and (5) carboxylic acid vinyl monomer. Monomer, (6) vinyl ether monomer, (7) olefin monomer, (8) ethylenically unsaturated carboxylic acid monomer, (9) vinyl halide monomer, (10) maleimide monomer And (11) a crosslinking agent.

More specifically, examples of (1) methacrylate include ethyl methacrylate, butyl methacrylate, propyl methacrylate, and 2-ethylhexyl methacrylate.
(2) Examples of the acrylate include methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, 2-ethylhexyl acrylate, and glycidyl acrylate.
(3) Examples of the vinyl cyanide monomer include acrylonitrile and methacrylonitrile.
(4) Examples of the diene monomer include butadiene, isoprene, dimethylbutadiene, and the like.
(5) Examples of the carboxylic acid vinyl monomer include vinyl acetate and vinyl butyrate.
(6) Examples of vinyl ether monomers include vinyl methyl ether and vinyl ethyl ether.
(7) Examples of the olefin monomer include ethylene, propylene, isobutylene and the like.
(8) Examples of the ethylenically unsaturated carboxylic acid monomer include acrylic acid, methacrylic acid, maleic acid, itaconic acid, and the like.
(9) Examples of the vinyl halide monomer include vinyl chloride and vinylidene chloride.
(10) Examples of the maleimide monomer include maleimide, N-phenylmaleimide, N-cyclohexylmaleimide, N-methylmaleimide and the like.
(11) Examples of the crosslinking agent include allyl (meth) acrylate, divinylbenzene, 1,3-butylene dimethacrylate, and the like.

  The (B) acrylic modifier preferably contains (1) methacrylate, (2) acrylate, and (3) vinyl cyanide monomer as the accessory monomer unit. From the viewpoint of suppressing thermal decomposition of the acrylic modifier, it is particularly preferable that (2) acrylate is contained. The monomer unit of the accessory component may be composed of a single type or may include a plurality of types.

  (B) When the acrylic modifier contains monomer units as subcomponents, the total content of monomers contained in (B) the acrylic modifier is 100% by weight. Is 20 to 94.9% by weight, the content of the aromatic vinyl monomer is 5 to 79.9% by weight, and the content of the accessory monomer unit is 0.1 to 10%. It is preferable that it is weight%.

  (B) The weight average molecular weight of an acrylic type modifier becomes like this. Preferably it is 5000-30000, More preferably, it is 10000-25000. (B) Acrylic modifier has good compatibility with (A) polycarbonate resin when the weight average molecular weight is 5000-30000, and (A) when the weight average molecular weight is 10000-25000 (A ) Compatibility with polycarbonate resin is further improved. Due to the good compatibility between (A) the polycarbonate resin and (B) the acrylic modifier, a high surface hardness in the polycarbonate resin composition can be obtained.

(B) The weight average molecular weight of an acrylic modifier can be measured on condition of the following using gel permeation chromatography (GPC), for example.
GPC columns: TOSOH TSK guardcolumn SuperMP (Hz) -M, TOSOH TSK SuperMultiple Hz-M
Mobile phase: THF was used.

  (B) The monomer polymerization method for obtaining the acrylic modifier is, for example, a suspension polymerization method or a bulk polymerization method, and is preferably a suspension polymerization method. The polymerization method may be other known methods, for example, an emulsion polymerization method. (B) The acrylic modifier may contain additives and the like as necessary. Examples of the additive include a polymerization initiator, an emulsifier, a dispersant, and a chain transfer agent.

<(C) Graft copolymer>
The (C) graft copolymer according to this embodiment is a graft copolymer in which the main chain is polycarbonate (PC) and the side chain is a polymethyl methacrylate copolymer. (C) The polymethyl methacrylate copolymer in the side chain of the graft copolymer is polymethyl methacrylate (PMMA), which is a copolymer of methyl methacrylate (MMA), or methyl methacrylate and aromatic vinyl monomer It is a copolymer with the body.

  (C) The graft copolymer has a main chain component content of 40 to 90% by weight and a side chain component content of 100% by weight of the total content of the main chain component and side chain component. 10 to 60% by weight. Thereby, the surface hardness and transparency in a polycarbonate resin composition can be improved.

  Furthermore, the (C) graft copolymer preferably has a main chain component content of 50 to 80% by weight and a side chain component content of 20 to 50% by weight. Thereby, the surface hardness in a polycarbonate resin composition can further be improved.

  Further, by making the content of the main chain component 50% by weight or more and the content of the side chain component 50% by weight or less, the main chain component and the side chain component are not produced during the production of the (C) graft copolymer. Since it becomes difficult to block, manufacture of the (C) graft copolymer becomes easy.

  (C) By making the polymethyl methacrylate copolymer in the side chain of the graft copolymer into a copolymer of methyl methacrylate (MMA) and an aromatic vinyl monomer, the surface hardness in the polycarbonate resin composition, Transparency and mechanical properties can be improved more favorably.

  However, the content of methyl methacrylate in the polymethyl methacrylate copolymer in the side chain of the (C) graft copolymer needs to be 10% by weight or more. Thereby, good surface hardness, transparency and mechanical properties in the polycarbonate resin composition are ensured.

  The aromatic vinyl monomer to be polymerized with methyl methacrylate is, for example, phenyl methacrylate (PhMA) or benzyl methacrylate (BzMA), and is preferably phenyl methacrylate. However, the aromatic vinyl monomer is not limited to a specific type, and may be, for example, styrene (St).

[Resin molded product]
Since the polycarbonate resin composition according to this embodiment is a thermoplastic resin, it can be easily molded into various shapes by injection molding, extrusion molding, or the like. Since the resin molded product obtained by molding the polycarbonate resin composition according to the present embodiment is excellent in surface hardness, transparency, and mechanical properties, such as electronic equipment, OA equipment, automobile parts, interior members, exterior members, etc. Widely applicable to various fields.

  Examples of the present invention will be described below. In addition, this invention is not limited to a following example.

[Preparation of test piece]
About Examples 1-1 to 1-7, 2-1 to 2-8, 3-1 to 3-5, and Comparative Examples 1 to 11, (A) polycarbonate resin, (B) acrylic modifier, and ( C) The test piece which is a resin molded product of the polycarbonate resin composition according to the above embodiment was produced by changing the type and amount of the graft copolymer.

(Example 1-1)
"(A) Polycarbonate resin"
Commercially available Iupilon S-3000 (manufactured by Mitsubishi Engineering Plastics) was used.

"(B) Acrylic modifier"
(B) Acrylic modifier (Modifier B-1) obtained by the following production method was used.

  In a heatable reaction vessel equipped with a thermometer, a nitrogen introduction tube, a reflux condenser, and a stirring device, the total amount of methyl methacrylate and phenyl methacrylate is 100 parts by weight, and 200 parts by weight of deionized water and a dispersant. 0.3 parts by weight, 0.5 parts by weight of sodium sulfate, 0.3 parts by weight of 2,2′-azobisisobutyronitrile, 30 parts by weight of phenyl methacrylate, 70 parts by weight of methyl methacrylate, N -The octyl mercaptan 1.8 weight part was prepared, the inside of reaction container was substituted with nitrogen, and it heated up at 80 degreeC. After stirring the inside of the reaction vessel for 4 hours, the obtained bead polymer was washed with water and dried to obtain a (meth) acrylate copolymer (Modifier B-1).

  The obtained (meth) acrylate copolymer had a mass average molecular weight of 15,000. The mass average molecular weight is a value in terms of polystyrene measured by GPC using THF as a solvent.

"(C) Graft copolymer"
The (C) graft copolymer obtained by the following production method was used.

  In a stainless steel autoclave having an internal volume of 5 L, 2500 g of pure water was put, and 2.5 g of polyvinyl alcohol was dissolved as the pure suspending agent. Next, 700 g of polycarbonate (trade name “Iupilon H-2000”, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) was added to the autoclave and dispersed by stirring.

  Separately from the above, 1.5 g of benzoyl peroxide (trade name “Nyper BW”, manufactured by NOF Corporation) as a radical polymerization initiator, and T-butylperoxymethacryloyloxyethyl carbonate as a radical (co) polymerizable organic peroxide 6 g and 0.6 g of N-dodecyl mercaptan as a molecular weight modifier were dissolved in 300 g of methyl methacrylate as a vinyl monomer.

  Next, the obtained solution was put into the autoclave and stirred. The autoclave was heated to 60 to 65 ° C. and stirred for 2 hours to impregnate the polycarbonate with a vinyl monomer containing a radical polymerization initiator and a radical (co) polymerizable organic peroxide. Then, the grafting precursor was obtained by heating up an autoclave to 80-85 degreeC, and maintaining and polymerizing at this temperature for 5 hours.

  Finally, this grafted precursor was extruded at 250 ° C. with a lab plast mill single screw extruder (manufactured by Toyo Seiki Seisakusho Co., Ltd.) and grafted to obtain white pellets of (C) graft copolymer.

  In Example 1-1, (C) the polycarbonate (main chain component) in the graft copolymer is 70% by weight, and (C) the polymethyl methacrylate (side chain component) in the graft copolymer is 30% by weight. is there.

"Polycarbonate resin composition"
(A) Polycarbonate resin, (B) Acrylic modifier, and (C) Graft copolymer are melt kneaded (extrusion temperature: 240 to 250 ° C.) with a twin screw extruder (PCM-30: manufactured by Ikekai). A pellet of a polycarbonate resin composition was obtained.

  In the following description, for each amount of (A) polycarbonate resin, (B) acrylic modifier, and (C) graft copolymer, (A) polycarbonate resin and (B) acrylic modifier The total amount is shown as being 100 parts by weight.

  In Example 1-1, the amount of (A) polycarbonate resin is 70 parts by weight, the amount of (B) acrylic modifier is 30 parts by weight, and the amount of (C) graft copolymer is 5 parts by weight. Part.

"Resin molding"
A polycarbonate resin composition was injection molded (barrel temperature: 250 to 260 ° C., mold temperature: 80 ° C.), and a test piece (150 mm × 100 mm × 2 mm rectangular resin molded product and No. 1 dumbbell-shaped resin molded product) Was made.

(Example 1-2)
In Example 1-2, only the amount of (C) graft copolymer is different from Example 1-1, and the amount of (C) graft copolymer is 1 part by weight.

(Example 1-3)
In Example 1-3, only the amount of (C) graft copolymer is different from Example 1-1, and the amount of (C) graft copolymer is 15 parts by weight.

(Example 1-4)
In Example 1-4, only the amount of (A) polycarbonate resin and (B) acrylic modifier is different from Example 1-1, the amount of (A) polycarbonate resin is 90 parts by weight, and (B) The amount of the acrylic modifier is 10 parts by weight.

(Example 1-5)
In Example 1-5, only the amount of (A) polycarbonate resin and (B) acrylic modifier is different from Example 1-1, the amount of (A) polycarbonate resin is 60 parts by weight, and (B) The amount of the acrylic modifier is 40 parts by weight.

(Example 1-6)
In Example 1-6, only the amount of (A) polycarbonate resin and (B) acrylic modifier is different from Example 1-1, the amount of (A) polycarbonate resin is 40 parts by weight, and (B) The amount of the acrylic modifier is 60 parts by weight.

(Example 1-7)
In Example 1-7, only the ratio of the main chain component and the side chain component in the (C) graft copolymer is different from that in Example 1-1, and the polycarbonate (main chain component) of the (C) graft copolymer is different. 90% by weight and (C) polymethyl methacrylate (side chain component) of the graft copolymer is 10% by weight.

(Example 2-1)
In Example 2-1, only the side chain of the (C) graft copolymer is different from Example 1-1, and the side chain of the (C) graft copolymer is a copolymer of methyl methacrylate and styrene (St). The amount of methyl methacrylate is 27% by weight and the amount of styrene is 3% by weight.

(Example 2-2)
In Example 2-2, only the side chain of the (C) graft copolymer is different from Example 1-1, and the side chain of the (C) graft copolymer is a copolymer of methyl methacrylate and benzyl methacrylate (BzMA). Polymer, the amount of methyl methacrylate is 27% by weight and the amount of benzyl methacrylate is 3% by weight.

(Example 2-3)
In Example 2-3, only the side chain of the (C) graft copolymer is different from Example 1-1, and the side chain of the (C) graft copolymer is a copolymer of methyl methacrylate and phenyl methacrylate (PhMA). Polymer, the amount of methyl methacrylate is 27% by weight and the amount of phenyl methacrylate is 3% by weight.

(Example 2-4)
In Example 2-4, only the side chain of (C) graft copolymer is different from Example 1-1, and the side chain of (C) graft copolymer is methyl methacrylate, styrene (St), benzyl A copolymer of methacrylate (BzMA) and phenyl methacrylate (PhMA), the amount of methyl methacrylate is 27% by weight, the amount of styrene is 1% by weight, and the amount of benzyl methacrylate is 1% by weight. And the amount of phenyl methacrylate is 1% by weight.

(Example 2-5)
In Example 2-5, only the side chain of the (C) graft copolymer is different from Example 1-1, and the side chain of the (C) graft copolymer is a copolymer of methyl methacrylate and phenyl methacrylate (PhMA). Polymer, the amount of methyl methacrylate is 25% by weight and the amount of phenyl methacrylate is 5% by weight.

(Example 2-6)
In Example 2-6, only the side chain of the (C) graft copolymer and the ratio of the main chain component to the side chain component are different from those of Example 1-1, and the side chain of the (C) graft copolymer is different. It is a copolymer of methyl methacrylate and styrene (St), the amount of polycarbonate (main chain component) is 50% by weight, the amount of methyl methacrylate (side chain component) is 35% by weight, and styrene ( The amount of the side chain component) is 15% by weight.

(Example 2-7)
In Example 2-7, only the side chain of (C) the graft copolymer and the ratio of the main chain component to the side chain component are different from Example 1-1, and the side chain of (C) the graft copolymer is different. It is a copolymer of methyl methacrylate and benzyl methacrylate (BzMA), the amount of polycarbonate (main chain component) is 50% by weight, the amount of methyl methacrylate (side chain component) is 35% by weight, and benzyl The amount of methacrylate (side chain component) is 15% by weight.

(Example 2-8)
In Example 2-8, only the side chain of the (C) graft copolymer and the ratio of the main chain component to the side chain component are different from those in Example 1-1, and the side chain of the (C) graft copolymer is different. It is a copolymer of methyl methacrylate and phenyl methacrylate (PhMA), the amount of polycarbonate (main chain component) is 50% by weight, the amount of methyl methacrylate (side chain component) is 35% by weight, The amount of methacrylate (side chain component) is 15% by weight.

(Example 3-1)
In Example 3-1, only (B) acrylic modifier was different from Example 1-1, and (B) 30% by weight of benzyl methacrylate and 70% by weight of methyl methacrylate were used as the acrylic modifier. The modifier B-2 comprised from these was used.

(Example 3-2)
In Example 3-2, only (B) acrylic modifier was different from Example 2-1, and (B) 30% by weight of benzyl methacrylate and 70% by weight of methyl methacrylate were used as the acrylic modifier. The modifier B-2 comprised from these was used.

(Example 3-3)
In Example 3-3, only (B) acrylic modifier is different from Example 2-1, and (B) 60% by weight of benzyl methacrylate and 40% by weight of methyl methacrylate are used as the acrylic modifier. The modifier B-3 comprised from these was used.

(Example 3-4)
In Example 3-4, only (B) acrylic modifier was different from Example 2-1, and (B) 20% by weight benzyl methacrylate and 80% by weight methyl methacrylate were used as the acrylic modifier. The modifier B-4 comprised from these was used.

(Example 3-5)
In Example 3-5, only (A) polycarbonate resin was different from Example 3-4, and commercially available Tufflon A2200 (manufactured by Idemitsu Kosan Co., Ltd.) was used as (A) polycarbonate resin.

(Comparative Example 1)
Comparative Example 1 differs from Example 1-1 in that it does not contain (C) the graft copolymer.

(Comparative Example 2)
In Comparative Example 2, only the amount of (C) the graft copolymer is different from Example 1-1, and the amount of (C) the graft copolymer is 30 parts by weight. That is, in the polycarbonate resin composition according to Comparative Example 2, the amount of (C) the graft copolymer is larger than 20 parts by weight which is the upper limit of the polycarbonate resin composition according to the above embodiment.

(Comparative Example 3)
In Comparative Example 3, only the amount of (C) graft copolymer is different from Example 1-1, and the amount of (C) graft copolymer is 0.1 parts by weight. That is, in the polycarbonate resin composition according to Comparative Example 3, the amount of (C) the graft copolymer is less than 0.5 parts by weight which is the lower limit of the polycarbonate resin composition according to the above embodiment.

(Comparative Example 4)
In Comparative Example 4, only (C) the graft copolymer was different from Example 1-1, and instead of (C) the graft copolymer, a mixture of polycarbonate and polymethyl methacrylate that had not been graft copolymerized was used. It was.

(Comparative Example 5)
In Comparative Example 5, only the ratio of the main chain component to the side chain component in (C) the graft copolymer was different from Example 1-1, and the polycarbonate (main chain component) in (C) the graft copolymer was 30 wt. % And (C) polymethyl methacrylate (side chain component) of the graft copolymer is 70% by weight. That is, in the polycarbonate resin composition according to Comparative Example 5, the ratio of the main chain component in the (C) graft copolymer is lower than 40% by weight, which is the lower limit of the polycarbonate resin composition according to the above embodiment. ) The ratio of the side chain component in the graft copolymer is higher than 60% by weight which is the upper limit of the polycarbonate resin composition according to the above embodiment.

(Comparative Example 6)
In Comparative Example 6, only the ratio of the main chain component to the side chain component in (C) the graft copolymer was different from Example 1-1, and the polycarbonate (main chain component) in (C) the graft copolymer was 95 wt. % Of the polymethyl methacrylate (side chain component) of the (C) graft copolymer. That is, in the polycarbonate resin composition according to Comparative Example 6, the ratio of the main chain component in the (C) graft copolymer is higher than 90% by weight which is the upper limit of the polycarbonate resin composition according to the above embodiment, and (C ) The ratio of the side chain component in the graft copolymer is lower than 10% by weight which is the lower limit of the polycarbonate resin composition according to the above embodiment.

(Comparative Example 7)
In Comparative Example 7, only the amount of (A) polycarbonate resin and (B) acrylic modifier was different from Example 1-1, the amount of (A) polycarbonate resin was 30 parts by weight, and (B) acrylic The amount of modifier is 70 parts by weight. That is, in the polycarbonate resin composition according to Comparative Example 7, the amount of (B) acrylic modifier is greater than 60 parts by weight, which is the upper limit of the polycarbonate resin composition according to the above embodiment.

(Comparative Example 8)
In Comparative Example 8, only the amount of (A) polycarbonate resin and (B) acrylic modifier was different from Example 1-1, the amount of (A) polycarbonate resin was 97 parts by weight, and (B) acrylic The amount of modifier is 3 parts by weight. That is, in the polycarbonate resin composition according to Comparative Example 8, the amount of (B) acrylic modifier is less than 5 parts by weight which is the lower limit of the polycarbonate resin composition according to the above embodiment.

(Comparative Example 9)
In Comparative Example 9, only (C) the graft copolymer was different from Example 1-1, and instead of (C) the graft copolymer, a polycarbonate that was not graft copolymerized and polymethyl methacrylate (PMMA) And a mixture of phenyl methacrylate.

(Comparative Example 10)
In Comparative Example 10, only the side chain of the (C) graft copolymer is different from Example 1-1, and the side chain of the (C) graft copolymer is a copolymer of methyl methacrylate and styrene. The amount of methyl acid is 3% by weight and the amount of styrene is 27% by weight. That is, in the polycarbonate resin composition according to Comparative Example 10, the amount of methyl methacrylate in the side chain of the (C) graft copolymer is less than 10% by weight which is the lower limit of the polycarbonate resin composition according to the above embodiment. .

(Comparative Example 11)
Comparative Example 11 differs from Example 3-1 in that it does not contain (C) the graft copolymer.

[Evaluation method]
(Evaluation of surface hardness)
Pencil hardness measurement was performed as an evaluation of the surface hardness of each test piece. The pencil hardness measurement was performed using a pencil hardness measuring machine (a pencil scratch coating film hardness tester manufactured by Toyo Seiki Co., Ltd.) in accordance with JISK5600-5-4. No scratches were observed on the surface of the test piece having a pencil hardness of HB or higher.

(Evaluation of transparency)
As an evaluation of the transparency of each test piece, a haze value (unit: “%”) was measured. The haze value is a value used as a measure of the turbidity of the resin, and the smaller the value, the higher the transparency. The haze value was measured using an NDH-2000 type haze meter manufactured by Nippon Denshoku Industries Co., Ltd. A test piece having a haze value of 1.0% or less was considered to have good transparency.

(Evaluation of bending strength maintenance rate)
About each test piece, the bending strength maintenance factor which shows the change of the bending strength by addition of (C) graft copolymer was calculated | required as follows.

First, the bending strength of each test piece was measured at a test speed of 2 mm / min according to JIS K-7203. From the bending strength obtained by the measurement, the bending strength maintenance ratio (%) was calculated using the following formula (1).
Formula (1):
(Bending strength maintenance factor) = 100 × (bending strength of test piece) / ((C) bending strength of test piece not containing graft copolymer)

  In specimens with a bending strength maintenance rate exceeding 100%, the bending strength is improved by the addition of the (C) graft copolymer, and in specimens with a bending strength maintenance ratio of less than 100%, the (C) graft copolymer It can be seen that the bending strength is reduced by the addition.

(Evaluation of impact resistance maintenance rate)
About each test piece, the impact resistance maintenance factor which shows the change of impact resistance by addition of (C) graft copolymer was calculated | required as follows.

First, the Izod impact value of each test piece was measured under conditions with a notch in accordance with JIS K-7110. The bending impact resistance maintenance rate (%) was calculated from the Izod impact value obtained by the measurement using the following formula (2).
Formula (2):
(Impact resistance maintenance ratio) = (Izod impact value of test piece) / ((C) Izod impact value of test piece not containing graft copolymer)

  For specimens with an impact resistance maintenance ratio exceeding 100%, the Izod impact value was improved by adding the (C) graft copolymer, and for specimens with an impact resistance maintenance ratio of less than 100%, the (C) graft copolymer was improved. It can be seen that the Izod impact value is reduced by the addition of the polymer.

[Evaluation results (Examples 1-1 to 1-7)]
Table 1 shows the evaluation results of Examples 1-1 to 1-7.

(Examples 1-1 to 1-7)
As shown in Table 1, in any of the test pieces of Examples 1-1 to 1-7, the pencil hardness was HB or higher, and a high surface hardness was obtained. In any of the test pieces of Examples 1-1 to 1-7, the haze value was 1.0% or less, and good transparency was obtained. Furthermore, in any of the test pieces of Examples 1-1 to 1-7, the bending strength maintenance ratio and the impact resistance maintenance ratio exceed 100%, and the mechanical properties are improved by the addition of (C) the graft copolymer. It turns out that it is improving rather than being damaged.

[Evaluation results (Examples 2-1 to 2-8)]
Table 2 shows the evaluation results of Examples 2-1 to 2-8.

(Examples 2-1 to 2-8)
As shown in Table 2, in any of the test pieces of Examples 2-1 to 2-8, the pencil hardness was HB or higher, and a high surface hardness was obtained. In any of the test pieces of Examples 2-1 to 2-8, the haze value was 1.0% or less, and good transparency was obtained. Furthermore, in any of the test pieces of Examples 2-1 to 2-8, the bending strength maintenance ratio and the impact resistance maintenance ratio exceed 100%, and the mechanical properties are improved by the addition of (C) the graft copolymer. It turns out that it is improving rather than being damaged.

  In Examples 2-1 to 2-8, generally better results were obtained than in Examples 1-1 to 1-7 in any of surface hardness, transparency, and mechanical properties. In Examples 1-1 to 1-7, the side chain of the (C) graft copolymer is polymethyl methacrylate, whereas in Examples 2-1 to 2-8, the side of the (C) graft copolymer The chain is a copolymer of methyl methacrylate and an aromatic vinyl monomer. Therefore, (C) the graft copolymer has a side chain that is a copolymer of methyl methacrylate and an aromatic vinyl monomer, so that extremely good surface hardness, transparency, and mechanical properties can be obtained. I understand.

[Evaluation results (Examples 3-1 to 3-5)]
Table 3 shows the evaluation results of Examples 3-1 to 3-5.

(Examples 3-1 to 3-5)
As shown in Table 3, in any of the test pieces of Examples 3-1 to 3-5, the pencil hardness was HB or higher, and a high surface hardness was obtained. In any of the test pieces of Examples 3-1 to 3-5, the haze value was 1.0% or less, and good transparency was obtained. Furthermore, in any of the test pieces of Examples 3-1 to 3-5, the bending strength maintenance ratio and the impact resistance maintenance ratio exceed 100%, and the mechanical properties are improved by the addition of (C) the graft copolymer. It turns out that it is improving rather than being damaged.

[Evaluation results (Comparative Examples 1 to 11)]
Table 4 shows the evaluation results of Comparative Examples 1-11.

(Comparative Examples 1 and 11)
The polycarbonate resin compositions according to Comparative Examples 1 and 11 are composed only of (A) a polycarbonate resin and (B) an acrylic modifier without adding (C) a graft copolymer. In the polycarbonate resin compositions according to Comparative Examples 1 and 11, although a pencil hardness of HB or higher was obtained, the haze value was higher than 1.0%, and good transparency was not obtained.

  Comparison between Examples 1-1 and 3-1 and Comparative Examples 1 and 11 reveals that the transparency of the polycarbonate resin composition is improved by the addition of the (C) graft copolymer.

(Comparative Example 2)
In the polycarbonate resin composition according to Comparative Example 2, the amount of (C) the graft copolymer is larger than 20 parts by weight which is the upper limit of the polycarbonate resin composition according to the above embodiment. In this polycarbonate resin composition, a pencil hardness of HB or higher and a bending strength maintenance ratio and impact resistance maintenance ratio exceeding 100% are obtained, but the haze value is significantly higher than 1.0%, which is favorable. Transparency was not obtained.

  Comparison between Example 1-1 and Comparative Example 2 shows that the transparency of the polycarbonate resin composition is greatly improved by setting the addition amount of the (C) graft copolymer to 20 parts by weight or less.

(Comparative Example 3)
In the polycarbonate resin composition according to Comparative Example 3, the amount of (C) the graft copolymer is less than 0.5 parts by weight which is the lower limit of the polycarbonate resin composition according to the above embodiment. In this polycarbonate resin composition, a pencil hardness of HB or higher was obtained, and although the bending strength maintenance rate and the impact resistance maintenance rate were both 100%, the haze value was higher than 1.0% and good transparency was obtained. Sex was not obtained.

  Comparison between Example 1-1 and Comparative Example 3 shows that the transparency of the polycarbonate resin composition is improved by setting the amount of (C) the graft copolymer to 0.5 parts by weight or more.

(Comparative Example 4)
In the polycarbonate resin composition according to Comparative Example 4, instead of (C) the graft copolymer, a mixture of a polycarbonate that was not graft copolymerized and polymethyl methacrylate was used. In this polycarbonate resin composition, the pencil hardness was B, and high surface hardness was not obtained. Moreover, in this polycarbonate resin composition, the haze value was significantly higher than 1.0%, and good transparency was not obtained. Furthermore, in this polycarbonate resin composition, the bending strength maintenance rate and the impact resistance maintenance rate are both less than 100%, and the mechanical properties of (A) the polycarbonate resin and (B) the acrylic modifier are impaired. I understand that.

  Comparison between Example 1-1 and Comparative Example 4 shows that by using the (C) graft copolymer, all of the surface hardness, transparency, and mechanical properties of the polycarbonate resin composition are improved.

(Comparative Example 5)
In the polycarbonate resin composition according to Comparative Example 5, the ratio of the main chain component in the (C) graft copolymer is lower than 40% by weight, which is the lower limit of the polycarbonate resin composition according to the above embodiment. The ratio of the side chain component in the copolymer is higher than 60% by weight which is the upper limit of the polycarbonate resin composition according to the above embodiment. In this polycarbonate resin composition, a pencil hardness of HB or higher and a haze value of 1.0% or higher are obtained, but the bending strength maintenance ratio and the impact resistance maintenance ratio are both less than 100%. It can be seen that the mechanical properties of the polycarbonate resin and (B) acrylic modifier are impaired.

  By comparing Example 1-1 with Comparative Example 5, the main chain component in the (C) graft copolymer is 40% by weight or more, and the side chain component in the (C) graft copolymer is 60% by weight or less. This shows that the mechanical properties of the polycarbonate resin composition are improved.

(Comparative Example 6)
In the polycarbonate resin composition according to Comparative Example 6, the ratio of the main chain component in the (C) graft copolymer is higher than 90% by weight which is the upper limit of the polycarbonate resin composition according to the above embodiment, and (C) the graft The ratio of the side chain component in the copolymer is lower than 10% by weight which is the lower limit of the polycarbonate resin composition according to the above embodiment. In this polycarbonate resin composition, a pencil hardness of HB or higher and a bending strength maintenance ratio and impact resistance maintenance ratio exceeding 100% are obtained, but the haze value is higher than 1.0% and good transparency is obtained. Was not obtained.

  By comparing Example 1-1 with Comparative Example 6, the main chain component in (C) the graft copolymer is 90% by weight or less, and the side chain component in (C) the graft copolymer is 10% by weight or more. This shows that the transparency of the polycarbonate resin composition is improved.

(Comparative Example 7)
In the polycarbonate resin composition according to Comparative Example 7, the amount of (B) acrylic modifier is greater than 60 parts by weight which is the upper limit of the polycarbonate resin composition according to the above embodiment. In this polycarbonate resin composition, a pencil hardness of HB or higher and a bending strength maintenance ratio and impact resistance maintenance ratio exceeding 100% are obtained, but the haze value is significantly higher than 1.0%, which is favorable. Transparency was not obtained.

  Comparison between Example 1-1 and Comparative Example 7 revealed that the transparency of the polycarbonate resin composition was significantly improved by setting the amount of (B) acrylic modifier to 60 parts by weight or less. .

(Comparative Example 8)
In the polycarbonate resin composition according to Comparative Example 8, the amount of (B) acrylic modifier is less than 5 parts by weight which is the lower limit of the polycarbonate resin composition according to the above embodiment. In this polycarbonate resin composition, although a haze value of 1.0% or less and a bending strength maintenance ratio and an impact resistance maintenance ratio exceeding 100% are obtained, the pencil hardness is 2B and the surface hardness is low. It was.

  Comparison between Example 1-1 and Comparative Example 8 shows that the surface hardness of the polycarbonate resin composition is improved by setting the amount of (B) the acrylic modifier to 5 parts by weight or more.

(Comparative Example 9)
In the polycarbonate resin composition according to Comparative Example 9, a mixture of non-grafted polycarbonate, polymethyl methacrylate, and phenyl methacrylate was used instead of (C) the graft copolymer. In this polycarbonate resin composition, the pencil hardness was 2B, and a high surface hardness could not be obtained. Moreover, in this polycarbonate resin composition, the haze value was significantly higher than 1.0%, and good transparency was not obtained. Furthermore, in this polycarbonate resin composition, the bending strength maintenance rate and the impact resistance maintenance rate are both less than 100%, and the mechanical properties of (A) the polycarbonate resin and (B) the acrylic modifier are impaired. I understand that.

  Comparison between Example 1-1 and Comparative Example 9 shows that by using the (C) graft copolymer, all of the surface hardness, transparency, and mechanical properties of the polycarbonate resin composition are improved.

(Comparative Example 10)
In the polycarbonate resin composition according to Comparative Example 10, the amount of methyl methacrylate in the side chain of the (C) graft copolymer is less than 10% by weight which is the lower limit of the polycarbonate resin composition according to the above embodiment. In this polycarbonate resin composition, the pencil hardness was B, and high surface hardness was not obtained. Moreover, in this polycarbonate resin composition, the haze value was significantly higher than 1.0%, and good transparency was not obtained. Furthermore, in this polycarbonate resin composition, the bending strength maintenance rate and the impact resistance maintenance rate are both less than 100%, and the mechanical properties of (A) the polycarbonate resin and (B) the acrylic modifier are impaired. I understand that.

  By comparing the amount of methyl methacrylate in the side chain of (C) the graft copolymer with 10% by weight or more by comparing Example 1-1 and Comparative Example 9, the surface hardness and transparency of the polycarbonate resin composition It can be seen that both the mechanical properties are improved.

  As mentioned above, although embodiment of this invention was described, this invention is not limited only to the above-mentioned embodiment, Of course, a various change can be added.

  For example, the polycarbonate resin composition may contain known additives such as an antistatic agent, a flame retardant, and a lubricant as necessary. Examples of the antistatic agent include Denon V-57S (manufactured by Maruhishi Oil Chemical Co., Ltd.), which is an anionic activator. Examples of the flame retardant include triphenyl phosphate. Examples of the lubricant include stearyl stearate.

Claims (4)

(A) a polycarbonate resin, (B) an acrylic modifier, and (C) a graft copolymer,
When the total content of the (A) polycarbonate resin and the (B) acrylic modifier is 100 parts by weight, the content of the (B) acrylic modifier is 5 to 60 parts by weight, (C) The content of the graft copolymer is 0.5 to 20 parts by weight,
The (C) graft copolymer is composed of 40 to 90% by weight of polycarbonate and 10 to 60% by weight of polymethyl methacrylate copolymer, the main chain is the polycarbonate, and the side chain is the above-mentioned A polymethyl methacrylate copolymer,
The polymethyl methacrylate copolymer is a polycarbonate resin composition containing 10% by weight or more of methyl methacrylate. The polycarbonate resin composition according to claim 1,
The polymethyl methacrylate copolymer is a copolymer of methyl methacrylate and an aromatic vinyl monomer. Polycarbonate resin composition. The polycarbonate resin composition according to claim 1 or 2,
The polycarbonate resin composition, wherein the (B) acrylic modifier is a copolymer of methyl methacrylate and an aromatic vinyl monomer. A resin molded product obtained by molding the polycarbonate resin composition according to any one of claims 1 to 3.