JP6413427B2 - PC / ABS resin composition and resin molded product thereof - Google Patents

Description

  The present invention relates to a PC / ABS resin composition which is a thermoplastic resin having a good molded appearance and excellent scratch resistance and squeak noise reduction effect, and a resin molded product thereof.

  Polycarbonate (PC) / ABS resin (ABS) is a thermoplastic resin mixture that has improved processability while maintaining high notch impact strength, and has relatively high heat resistance, so it can be used in automobile parts, computer housings, etc. It is applied to large projectiles that generate a lot of heat, such as office equipment. Furthermore, it is excellent in flame retardancy, and its use area has been increasing in recent years.

  As a general method for solving the scratch resistance of a thermoplastic resin, Patent Document 1 discloses that a hard coat layer is obtained by applying and curing an ultraviolet curable acrylic hard coat agent on the surface of a final molded thermoplastic resin. Is disclosed. Further, as an effective means for preventing or reducing squeaking noise, Patent Document 2 applies a fluorine-based or silicone-based coating composition as a surface treatment agent.

Japanese Patent Application Laid-Open No. 6-100799 JP-A-3-217425

  However, in the case of the methods described in Patent Document 1 and Patent Document 2, an additional process called a coding process is required, which requires a lot of time in the process, which not only increases costs but also causes environmental problems. Has the disadvantages. In addition, when using a surface treatment agent as in Patent Document 2, there are problems such as surface stickiness and appearance deterioration.

  Therefore, in recent years, there has been an increasing demand for an unpainted resin capable of improving scratch resistance (scratch resistance) without hard coating and reducing squeaking noise. In addition, the development of a resin with excellent scratch resistance is highly desired in the exterior material industry.

  Accordingly, the present invention solves the above-mentioned problems, and a PC / ABS resin composition that has a good molded appearance and excellent scratch resistance and squeaking noise reduction effect while not requiring hard coding after molding, It aims at providing the resin molded product.

  For that purpose, the PC / ABS resin composition of the present invention comprises (a) 50 to 90 parts by weight of polycarbonate (PC), (b) 50 to 10 parts by weight of ABS resin (ABS), and (c). 0.5 to 20 parts by weight of a graft copolymer of polyethylene as a main chain and acrylonitrile-styrene copolymer as a side chain with respect to a total of 100 parts by weight of the component (a) and the component (b). It contains. In the acrylonitrile-styrene copolymer, the weight ratio of the acrylonitrile (AN) component to the styrene (St) component is AN / St = 10/90 to 50/50.

  At this time, it is preferable that 40 to 90 wt% of the polyethylene component (PE) and 60 to 10 wt% of the acrylonitrile-styrene copolymer are contained in the (c) graft copolymer. The total of the PE component and the polyacrylonitrile-styrene copolymer component is 100 wt%.

  Moreover, according to this invention, the resin composition formed by shape | molding the said PC / ABS resin composition in a predetermined shape can also be provided.

  “PC / ABS” means a mixed resin composition. Further, in the present invention, “XX to XX” indicating a numerical range means “XX or more and XX or less” unless otherwise specified.

  According to the present invention, for the mixed resin composition of PC and ABS, (c) a graft copolymer having a main chain of polyethylene and a side chain of acrylonitrile-styrene copolymer is specified as an additive. By blending in an amount, the scratch resistance of the resin molded product itself can be improved and the squeaking noise can be reduced. Therefore, the resin molded product made of the PC / ABS resin composition of the present invention does not require a hard coding process for improving scratch resistance and reducing squeaking noise, and the appearance of the resin molded product is also improved.

  Next, each component of the present invention will be described. The resin composition of the present invention is obtained by adding a specific (c) graft copolymer as an additive to a mixed resin composition of (a) polycarbonate (PC) and (b) ABS resin (ABS).

<(A) PC>
The polycarbonate (a) used in the present invention is a polymer 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. Typical examples include polycarbonate resins made from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), both with and without terminal OH groups sealed Can also be used.

<(B) ABS>
(B) The ABS resin used in the present invention is a resin mainly composed of a copolymer mainly composed of three components of acrylonitrile-butadiene-styrene, and any known ABS resin can be used.

  Moreover, about the (a) component and (b) component, the polymer alloy which is a blended product of the commercially available (a) polycarbonate (PC) and (b) ABS resin (ABS) can also be used.

<(C) Graft copolymer>
The (c) graft copolymer used in the present invention is a graft copolymer in which the main chain is polyethylene (PE) and the side chain is an acrylonitrile-styrene copolymer. The graft copolymer preferably has a polyethylene component of 40 to 90 wt% and an acrylonitrile-styrene copolymer component of 60 to 10 wt% (the total of both components is 100 wt%). When the blending balance of the polyethylene component and the acrylonitrile-styrene copolymer component is out of this range, the scratch resistance of the resulting resin molded product is lowered. More preferably, the polyethylene component is 80 wt% or less and the acrylonitrile-styrene copolymer is 20 wt% or more. In this case, the scratch resistance of the resin molded product can be further enhanced. In addition, when the polyethylene component is 50 wt% or more and the acrylonitrile-styrene component is 50 wt% or less, polyethylene and acrylonitrile-styrene copolymer are difficult to block during the production of the graft copolymer, and the graft copolymer is easy to produce. Therefore, it is preferable. As the graft copolymer, any known one can be used as long as the above-described conditions are satisfied. Examples of commercially available products include NOF MODIPER A1401.

  The weight ratio of the acrylonitrile (AN) component to the styrene (St) component in the acrylonitrile-styrene copolymer component which is a side chain of the graft copolymer is AN / St = 10/90 to 50/50. . When this weight ratio is not satisfied, the effect of improving the scratch resistance and the effect of reducing squeaking noise in the resin molded product tend to be reduced.

<Combination ratio>
The PC / ABS resin composition of the present invention comprises (a) PC + (b) ABS in a total of 100 parts by weight, wherein (a) PC is 50 to 90 parts by weight and (b) ABS is 50 to 10 parts by weight. Moreover, the addition amount of (c) graft copolymer shall be 0.5-20 weight part with respect to 100 weight part of (a) PC + (b) ABS total. When the content of the components (a), (b), and (c) is out of the above range, excellent scratch resistance and squeaking noise reduction effect cannot be obtained in the resin molded product.

  In the resin composition of the present invention, known additives such as an antistatic agent, a flame retardant, and a lubricant can be added within a range not departing from the effects of the present invention. 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.

  Since the PC / ABS resin composition of the present invention is a thermoplastic resin, it is excellent in scratch resistance when molded into a predetermined shape by injection molding, extrusion molding, etc., and is less likely to cause squeaking noise when rubbed against other members A molded product can be obtained. As a result, the resin molded product is improved in scratch resistance and squeaking noise reduction effect without adding a coding process that has been a problem in the past, and the appearance of the resin molded product is also improved. Since the molded article of the present invention has properties excellent in scratch resistance and squeaking noise reduction effect, it is extremely useful in various fields such as automobiles, OA electronic devices, and electrical / electronic devices.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

[Example 1]
(A) Polycarbonate resin (made by Idemitsu Kosan Co., Ltd., trade name: Toughlon A2200, standard grade) as component (A), ABS resin (made by Asahi Kasei Chemicals Co., Ltd., trade name: Stylac 321, standard grade) as component (b) , (C) Graft copolymer (PE / AN / St = 50 wt% / 15 wt% / 35 wt%) whose main chain is polyethylene and side chain is acrylonitrile-styrene copolymer (manufactured by NOF Corporation, Product name: Modiper A1401] was used. The ratios shown in Table 1, ie, 70 parts by weight of component (a), 30 parts by weight of component (b), and 3 parts by weight of component (c), were melt kneaded (extruded) by a twin screw extruder (PCM-30: made by Ikekai) Temperature: 230 to 250 ° C.) to obtain a pellet-shaped composition. Next, this pellet was injection-molded (barrel temperature: 250 to 260 ° C., mold temperature: 80 ° C.) to prepare a test piece (150 mm × 100 mm × 2 mm).

[Example 2]
(C) It is the same as that of Example 1 except having made the addition amount of the component 1 part by weight with respect to the total of 100 parts by weight of the component (a) + the component (b).

[Example 3]
(C) It is the same as that of Example 1 except having made the addition amount of the component into 15 weight part with respect to the total of 100 weight part of (a) component + (b) component.

[Example 4]
The same as Example 1 except that the ratio of component (a) / component (b) was changed to PC / ABS = 80 parts by weight / 20 parts by weight.

[Example 5]
The same as Example 1 except that the ratio of component (a) / component (b) was changed to PC / ABS = 60 parts by weight / 40 parts by weight.

[Example 6]
The same as Example 1 except that the ratio of component (a) / component (b) was changed to PC / ABS = 90 parts by weight / 10 parts by weight.

[ Reference Example 7]
(C) Implemented except that the ratio of polyethylene as the main chain in the graft polymer as the component and polyacrylonitrile and styrene constituting the side chain was changed to PE / AN / St = 90 wt% / 3 wt% / 7 wt%. Similar to Example 1.

[Example 8]
(C) Implemented except that the ratio of polyethylene, which is the main chain in the graft polymer as the component, and polyacrylonitrile and styrene constituting the side chain was changed to PE / AN / St = 40 wt% / 18 wt% / 42 wt%. Similar to Example 1.

[Example 9]
The same as Example 1 except that the polycarbonate resin used as the component (a) was changed to [SABIC Innovative Plastics, trade name: Lexan 101R, extrusion / blow molding grade].

[Example 10]
(B) The same as in Example 1 except that the ABS resin used as the component was changed to [Asahi Kasei Chemicals Co., Ltd., trade name: Stylac IM30, high impact grade].

[Example 11]
(B) The same as Example 1 except that the ABS resin used as the component was changed to [Toray Co., Ltd., trade name: Toyolac 600, extrusion grade].

[Example 12]
Example 1 except that component (a) / component (b) was PC / ABS [trade name: Bayblend T65XF, ratio (PC / ABS = 65 parts by weight / 35 parts by weight)] which is a commercially available blended product. It is the same.

[Example 13]
Example 1 except that component (a) / component (b) was PC / ABS [trade name: Bayblend T85XF, ratio (PC / ABS = 85 parts by weight / 15 parts by weight)] which is a commercially available blended product. It is the same.

[Example 14]
(C) Same as Example 1 except that the weight ratio of polyacrylonitrile and styrene constituting the side chain of the graft polymer as component is AN / St = 50 (25) wt% / 50 (25) wt%. is there.

[Example 15]
Example except that the weight ratio of polyacrylonitrile and styrene constituting the side chain of the graft polymer as component (c) was AN / St = 15 (7.5) wt% / 85 (42.5) wt% Same as 1.

[Comparative Example 1]
(C) It is the same as that of Example 1 except not adding a component.

[Comparative Example 2]
(C) It is the same as that of Example 1 except having made the addition amount of the component into 30 weight part with respect to 100 weight part in total of (a) component + (b) component.

[Comparative Example 3]
(C) It is the same as that of Example 1 except having made the addition amount of a component into 0.1 weight part with respect to a total of 100 weight part of (a) component + (b) component.

[Comparative Example 4]
(C) The same as Example 4 except that the component PE / P (AN / St) of polyethylene and acrylonitrile-styrene copolymer was used.

[Comparative Example 5]
(C) Except that the weight ratio of (polyacrylonitrile and styrene) constituting the side chain of the graft polymer as the component was AN / St = 85 (42.5) wt% / 15 (7.5) wt% The same as in the first embodiment.

[Comparative Example 6]
(C) The same as Example 1 except that the component was polyethylene.

[Comparative Example 7]
(C) It is the same as that of Example 4 except not adding a component.

[Comparative Example 8]
(C) It is the same as that of Example 11 except not adding a component.

[Comparative Example 9]
(C) It is the same as that of Example 5 except not adding a component.

[Comparative Example 10]
(C) It is the same as that of Example 9 except not adding a component.

[Comparative Example 11]
(C) It is the same as that of Example 10 except not adding a component.

[Comparative Example 12]
(C) It is the same as that of Example 11 except not adding a component.

[Comparative Example 13]
(C) It is the same as that of Example 12 except not adding a component.

[Comparative Example 14]
(C) It is the same as that of Example 13 except not adding a component.

  Using the obtained test pieces of Examples and Comparative Examples, scratch resistance, squeaking noise, and molded appearance were evaluated by the following methods.

<Evaluation of scratch resistance>
Using the Gakushin Abrasion Tester (manufactured by YASUDA, NO416-TMI), the test specimen and the cotton canvas were used under the conditions of cotton canvas Kanaki No. 3, vertical load 1000 g, and 100 reciprocations. And a test for rubbing with each other. The scratch resistance was evaluated by measuring the gloss value (60 °) before and after the test with a gloss meter and calculating the gloss change rate. The method for calculating the gross change rate is as follows. The smaller the rate of change in gloss, the better the scratch resistance.
Gloss change rate (%) = (Gloss value before test−Gloss value after test) / Gloss value before test × 100

<Evaluation of itchiness>
The obtained test piece was deburred by cutting it into a plate (60 mm × 100 mm × 2 mm) for rubbing sound evaluation test and the same material plate (50 mm × 25 mm × 2 mm) for rubbing against the other material. Conditioning was performed for 12 hours at 50 ° C. and humidity of 50%, respectively. Moreover, PC / ABS (70 weight part / 30 weight part), PA66, PBT, and the stainless steel plate were also prepared as a plate for partner materials (50 mm x 25 mm x 2 mm). The plate for the stagnation sound evaluation test and each plate as the counterpart material are fixed to a stick slip measuring device SSP-02 of Ziegler, and rubbed under the conditions of load = 10 N, 40 N, speed = 1 mm / s, 10 mm / s, respectively. The risk of squeaking noise when combined was measured. The stagnation sound risk value indicates that the smaller the value, the lower the risk of stagnation sound generation. The criteria for determining the risk of stagnation sound are as follows.
Itchy sound risk values 1 to 3: Low risk of squeaking noises 4 to 5: Slightly risking squeaking noises 6 to 10: High risk of squeaking noises

<Evaluation of molding appearance>
Regarding the molded appearance, the test piece (150 mm × 100 mm × 2 mm) was visually evaluated according to the following criteria.
○: Good (no flow mark, jetting, peeling, etc.)
X: Defect (existing flow mark, jetting, peeling, etc.)
Note that the flow mark is a poor appearance with a circular ripple near the gate of the molded product. Jetting is an appearance defect that causes a flow pattern of a snake-like resin on a molded product. Peeling means an appearance defect that can be caused after the resin has been peeled off from the surface of the molded appearance.

  Tables 1 to 6 summarize the compositions and evaluation results of Examples and Comparative Examples.

  (C) Comparing Comparative Examples 1 and 6 to 14 without adding a graft copolymer with the results of each example, (a) with respect to 100 parts by weight of a mixed resin composition of PC and (b) ABS, As component (c), 0.5 to 20 parts by weight of a graft copolymer of polyethylene as the main chain and acrylonitrile-styrene copolymer as the side chain is added to the resin molded product, thereby improving the scratch resistance. A sound reduction effect was recognized and the molded appearance was good. In addition, from the results of Comparative Example 5 and Examples 14 and 15, in the graft polymer added as component (c), the weight ratio of styrene (St) to 50 wt% of acrylonitrile (AN) constituting the side chain was 50 wt%. It has been clarified that a resin molded product having excellent scratch resistance and low risk of occurrence of squeaking noise can be obtained when the content is less than or equal to%.

  On the other hand, as a result of Comparative Example 2, even when the main chain is polyethylene and the side chain is an acrylonitrile-styrene copolymer graft copolymer as component (c), the addition amount is 30 parts by weight. If it is excessive, the appearance of the resin molded product becomes poor. As a result of Comparative Example 3, when the component (c) was as small as 0.1 part by weight, the resin molded product was not found to have an effect of improving scratch resistance and an effect of reducing squeaking noise.

  Further, as a result of Comparative Example 4 and Comparative Example 5, as component (c), polyethylene and acrylonitrile-styrene copolymer were each used alone or polyethylene alone was used, and (a) PC and (b) ABS mixed When added to the resin composition, the appearance of the resin molded product was poor.

Claims (2)

(A) 50 to 90 parts by weight of polycarbonate (PC);
(B) 50 to 10 parts by weight of ABS resin (ABS);
(C) 0.5 to 20 parts by weight of a graft copolymer of polyethylene as the main chain and acrylonitrile-styrene copolymer as the side chain based on 100 parts by weight of the total of the components (a) and (b) And containing
In 100 wt% of the component (c), the polyethylene component is 40 to 50 wt%, the acrylonitrile-styrene copolymer component is 60 to 50 wt%,
The acrylonitrile-styrene copolymer is a PC / ABS resin composition in which a weight ratio of an acrylonitrile (AN) component and a styrene (St) component is AN / St = 10/90 to 50/50. A resin molded product obtained by molding the PC / ABS resin composition according to claim 1 into a predetermined shape.