JP4817690B2 - Injection molded product and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic resin composition which comprises a polycarbonate resin and a polyphenylene resin and has excellent rigidity, excellent melt flowability, and improved moldability. <P>SOLUTION: This thermoplastic resin composition comprising a polycarbonate resin having at least one kind of repeating units represented by formula [1], and a polyphenylene resin comprising two kinds of specific repeating units is characterized by containing the polyphenylene resin in an amount of 1 to 99 pts.wt. per 100 pts.wt. of the total amount of the composition. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

The present invention relates to an injection-molded article formed from a molding material composed of a thermoplastic resin composition comprising a polycarbonate resin and a polyphenylene resin. More specifically, flexural modulus, and excellent in melt flowability, an injection molded article formed Ri by a thermoplastic resin composition having good moldability.

  Conventionally, polycarbonate resin obtained by reacting 2,2-bis- (4-hydroxyphenyl) propane (common name; bisphenol A) with a carbonate precursor such as phosgene or diphenyl carbonate has transparency, heat resistance, impact resistance, Due to its excellent mechanical properties and dimensional stability, it is widely used as an engineering plastic in many fields. However, in recent years, products in the electronics field have been made lighter, thinner, and smaller, and accordingly, a polycarbonate resin having further improved heat resistance and rigidity has been demanded. In general, in order to improve the heat resistance and rigidity of a polycarbonate resin, there is a method of copolymerizing bisphenols having a bulky structure that is difficult to move, and various polycarbonate resins have been proposed. For example, a polycarbonate resin mainly obtained from bisphenol having an adamantane structure (see, for example, Patent Document 1) or a polycarbonate resin based on a specific dihydroxydiphenylcycloalkane has been devised. (For example, refer to Patent Document 2) Further, a polycarbonate resin having a specific fluorene structure has been proposed (for example, refer to Patent Documents 3 and 4). However, the polycarbonate resin having these structures is excellent in heat resistance and rigidity because of its structure in which molecules do not move easily, but melt flowability is not always good, and there is a problem in injection moldability and extrusion moldability. As another method, a method of blending additives such as glass fiber and filler has been tried. However, although the above additives improve the rigidity of the polycarbonate resin composition, they tend to decrease the fluidity during molding, and these additives often appear on the surface of the molded product, causing poor appearance. There was a problem.

Japanese Patent Laid-Open No. 5-78467 JP-A-2-88634 JP-A-11-174424 JP-A-8-134198

The present invention solves the above-mentioned problems, and is injection-molded from a molding material comprising a thermoplastic resin composition comprising a polycarbonate resin and a polyphenylene resin having excellent rigidity and melt flowability and improved moldability. It is to provide an injection molded product .

  As a result of intensive research, the present inventors have found that a thermoplastic resin composition formed of a polycarbonate resin synthesized using a specific dihydric phenol and a polyphenylene resin having a specific structure in an arbitrary ratio is rigid. It has been found that it has excellent and good moldability and has led to the present invention.

Hereinafter, the present invention will be described in detail.
In the present invention, a polycarbonate resin obtained from 2,2-bis (4-hydroxyphenyl) propane,

At least one structural unit (A) selected from the group consisting of 1,4-phenylene, 1,3-phenylene and 1,2-phenylene , 1,4- (benzoylphenylene), 1,4- (4′-phenoxy) It consists of at least one structural unit (B) selected from the group consisting of ( benzoylphenylene ), and the ratio of unit (A) to unit (B) in the total bond repeating unit is (A) :( B) = 1 in molar ratio. A thermoplastic resin composition comprising a polyphenylene resin in the range of 99 to 99: 1, comprising a thermoplastic resin composition containing 20 to 80 parts by weight of the polyphenylene resin with respect to 100 parts by weight of the total composition. There is provided an injection-molded article which is injection-molded from a molding material satisfying the following (i) and (ii) and whose surface arithmetic average roughness (Ra) is 0.5 μm or less.
(I) a glass transition temperature of 120 ° C. to 180 ° C. der Rukoto of the molding material
(Ii) The bending elastic modulus measured according to ISO 178 using a test piece obtained by injection-molding a molding material is 2,700 MPa to 8,000 MPa.

Furthermore, according to the present invention, the polyphenylene resin has a ratio in the total bond repeating unit of (A) :( B) = 1: 99 to 99: 1 , and (A) :( B) = 5: 95 to 95: 5 is good Mashiku, (A) :( B) = 10: 90~90: 10 being most preferred. In that case, a thermoplastic resin composition having excellent compatibility with the polycarbonate resin and excellent rigidity is provided.

Further, according to the present invention, the content of reportage Rifeniren resin against the total weight 100 parts by weight the composition is 20 to 80 parts by weight, preferably 30 to 70 parts by weight. In that case, a thermoplastic resin composition having high rigidity and excellent moldability is provided. When the proportion of the polyphenylene resin is smaller than 20 parts by weight, the flexural modulus is insufficient, and when the proportion of the polyphenylene resin is larger than 80 parts by weight, the melt fluidity is poor and the moldability is poor.

The polycarbonate resin contained in the thermoplastic resin composition of the present invention is a polycarbonate resin that is a structural unit derived from 2,2-bis (4-hydroxyphenyl) propane.

Further, polyphenylene resin contained in the thermoplastic resin composition of the present invention, the rigidity of the thermoplastic resin is further improved, Repetitive return units 1,4-phenylene, 1,3-phenylene, 1,2-phenylene And a polyphenylene resin which is at least one structural unit selected from 1,4- (benzoylphenylene) and 1,4- (4′-phenoxybenzoylphenylene) is more preferable. A polyphenylene resin composed of structural units in which the repeating units are 1,3-phenylene and 1,4- (benzoylphenylene) is preferable.

  The thermoplastic resin composition of the present invention has a glass transition temperature of 120 ° C to 180 ° C, preferably 125 ° C to 165 ° C, more preferably 130 ° C to 160 ° C. When the glass transition temperature is lower than 120 ° C., the heat resistance is insufficient, which is not preferable, and when the glass transition temperature is higher than 180 ° C., the melt flowability is poor and molding failure occurs, and the moldability is inferior.

Further, fluidity of the thermoplastic resin composition of the present invention, 300 ° C., preferably from ^{5 cm} 3/10 minutes or more with a value of MVR at the measurement conditions of 1.2 kgf, more preferably 20 cm ^3/10 minutes or more, more preferably 30 cm ^3/10 minutes or more.

  The thermoplastic resin composition of the present invention has a flexural modulus measured in accordance with ISO178 of 2,700 MPa or more, preferably 2,900 MPa, more preferably 3,100 MPa or more. If the flexural modulus is less than 2,700 MPa, it is difficult to reduce the thickness of the molded body due to insufficient rigidity, which is not preferable.

  The thermoplastic resin composition of the present invention has an arithmetic average roughness (Ra) measured in accordance with JIS B0601-1994 of the surface of a molded article made of the thermoplastic resin of 0.5 μm or less, preferably 0.2 μm or less. More preferably, it is 0.1 μm or less. In addition, the rigidity enhancement by using an inorganic additive such as glass fiber is not preferable because the surface smoothness may be impaired in the precision transfer property to the mold.

  When preparing the composition of this invention, arbitrary methods are employ | adopted. For example, after mixing polyphenylene resin with polycarbonate resin in a solution state, the solvent is distilled off and then melted into pellets with a vent type extruder or the like, or polycarbonate resin and polyphenylene resin are super mixer, tumbler, nauter mixer, etc. And a method of pelletizing with a twin screw ruder or the like. Moreover, additives, such as a stabilizer, antioxidant, a light stabilizer, a coloring material, a sliding material, a mold release agent, can also be added as needed. Furthermore, in the extrusion process (pelletizing process) for obtaining a pellet-like polycarbonate resin for use in injection molding, compression molding, and injection compression molding, foreign matters are removed by passing through a sintered metal filter having a filtration accuracy of 10 μm in the molten state. Is preferred. In any case, it is necessary for the raw material resin before injection molding to keep the content of foreign matters, impurities, solvents, etc. as low as possible.

  The thermoplastic resin composition of the present invention is generally obtained by injection molding at a cylinder temperature of 260 ° C. to 400 ° C. and a mold temperature of 60 ° C. to 140 ° C., or obtained by bonding them.

  In the present invention, if necessary, the thermoplastic resin composition is blended with at least one phosphorus compound selected from the group consisting of phosphoric acid, phosphorous acid, phosphonic acid, phosphonous acid and esters thereof. Can do. The amount of the phosphorus compound is preferably 0.0001 to 0.05% by weight, more preferably 0.0005 to 0.02% by weight, and 0.001 to 0.01% by weight based on the thermoplastic resin composition. % Is particularly preferred. By blending this phosphorus compound, the thermal stability of the thermoplastic resin composition is improved, and a decrease in molecular weight during molding is prevented.

  The phosphorus compound is at least one phosphorus compound selected from the group consisting of phosphoric acid, phosphorous acid, phosphonic acid, phosphonous acid and esters thereof, and condensates thereof, preferably the following general formula

［式中、Ｒ^５〜Ｒ^１７は、それぞれ独立して、水素原子、メチル、エチル、プロピル、イソプロピル、ブチル、イソブチル、ｔｅｒｔ−ブチル、ペンチル、ヘキシル、ヘプチル、オクチル、ノニル、デシル、ドデシル、ヘキサデシル、オクタデシルなどの炭素原子数１〜２０のアルキル基、フェニル、トリル、ナフチルなどの炭素原子数６〜１５のアリール基またはベンジル、フェネチルなどの炭素原子数７〜１８のアラルキル基を表し、また１つの化合物中に２つのアルキル基が存在する場合は、その２つのアルキル基は互いに結合して環を形成していてもよい。］
よりなる群から選択された少なくとも１種のリン化合物である。

[Wherein, R ^{5 to} R ¹⁷ are each independently a hydrogen atom, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, hexadecyl. Represents an alkyl group having 1 to 20 carbon atoms such as octadecyl, an aryl group having 6 to 15 carbon atoms such as phenyl, tolyl and naphthyl, or an aralkyl group having 7 to 18 carbon atoms such as benzyl and phenethyl; When two alkyl groups are present in one compound, the two alkyl groups may be bonded to each other to form a ring. ]
At least one phosphorus compound selected from the group consisting of:

  Examples of the phosphorus compound represented by the above formula [6] include triphenyl phosphite, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tridecyl phosphite, and trioctyl phosphite. , Trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, 2,2-methylenebis (4 , 6-di-tert-butylphenyl) octyl phosphite.

  Examples of the phosphorus compound represented by the formula [7] include tributyl phosphate, trimethyl phosphate, triphenyl phosphate, triethyl phosphate, diphenyl monoorthoxenyl phosphate, dibutyl phosphate, dioctyl phosphate, diisopropyl phosphate, and the like. 8] includes phosphorous compounds such as tetrakis (2,4-di-tert-butylphenyl) -4,4-diphenylenephosphonite, and the compound represented by the above formula [9] Examples thereof include dimethyl benzenephosphonate, diethyl benzenephosphonate, dipropyl benzenephosphonate, and the like. The compound represented by the formula [10] is bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol. Over diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2,4-di -tert- butylphenyl) pentaerythritol diphosphite, and distearyl pentaerythritol phosphite.

  Among these phosphorus compounds, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tetrakis (2,4-di-tert-butylphenyl) -4,4-diphenylene Phosphonite is preferably used.

  Furthermore, the higher fatty acid ester of monohydric or polyhydric alcohol can also be added to the thermoplastic resin composition of this invention as needed.

  The higher fatty acid ester is preferably a partial ester or a total ester of a monovalent or polyhydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms. Further, partial esters or total esters of monohydric or polyhydric alcohols and saturated fatty acids include stearic acid monoglyceride, stearic acid monosorbate, behenic acid monoglyceride, pentaerythritol monostearate, pentaerythritol tetrastearate, propylene glycol. Examples thereof include monostearate, stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, 2-ethylhexyl stearate and the like. Of these, stearic acid monoglyceride and pentaerythritol tetrastearate are preferably used. The amount of the ester of the alcohol and higher fatty acid is preferably 0.01 to 2% by weight, more preferably 0.015 to 0.5% by weight, and 0.02 to 0% with respect to the thermoplastic resin composition. More preferred is 2% by weight. If the blending amount is within this range, it is preferable that the release property is excellent and the release agent does not migrate and adhere to the metal surface.

  To the thermoplastic resin composition of the invention, an antioxidant generally known for the purpose of preventing oxidation can be added. Examples thereof include phenolic antioxidants, specifically, for example, triethylene glycol-bis (3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate), 1,6 -Hexanediol-bis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate), pentaerythritol-tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) Propionate), octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl) -4-hydroxybenzyl) benzene, N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydride) Cinnamide), 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 3,9-bis {1 , 1-dimethyl-2- [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl} -2,4,8,10-tetraoxaspiro (5,5) undecane, etc. Is mentioned. The range of the preferable addition amount of these antioxidants is 0.0001 to 0.05 weight% with respect to the thermoplastic resin composition.

The thermoplastic resin composition used as a molding material for injection-molded article of the present invention is excellent in flexural rigidity and melt flowability represented by the elastic modulus, injection molding, is suitably used as compression molding material out morphism The industrial effects that it plays are exceptional.

Hereinafter, although an example is given and explained in detail, the present invention is not limited to this unless it exceeds the purpose. In the examples and comparative examples, “parts” is parts by weight. Evaluation was according to the following method.
(1) Glass transition temperature Using a thermal analysis system DSC-2910 manufactured by TA Instruments, measurement was performed under a nitrogen atmosphere (nitrogen flow rate: 40 ml / min) and a temperature increase rate of 20 ° C./min. .
(2) Fluidity (MVR)
Using the pellets, the amount of polymer (cm ³ ) that flowed out for 10 minutes at a temperature of 300 ° C. and a load of 1.2 kgf was measured with a semi-auto melt melter manufactured by Toyo Seiki in accordance with ISO 1133.
(3) Flexural modulus The pellet was dried at 120 ° C. for 5 hours and then measured according to ISO 178 using an injection molding machine [J75 EIII manufactured by JSW Co., Ltd.] using a test piece injection molded at a cylinder temperature of 280 ° C.
(4) Arithmetic mean roughness (Ra) of molded product surface
After drying the pellets at 120 ° C. for 5 hours, a disk-shaped mirror substrate having a diameter of 120 mm and a thickness of 1.2 mm was prepared using an injection molding machine M35B-D-DM manufactured by Meiki Seisakusho and a mold having a surface roughness of 0.01 μm. Molded. The arithmetic average roughness (Ra) of the surface of the obtained disk-shaped mirror substrate is 40 mm from the center to the outer periphery using a surface roughness shape measuring machine (Surfcoder SE1100 manufactured by Kosaka Laboratory) in accordance with JIS B0601-1994. Measurements were taken at a distance.

[Example 1]
Polyphenylene resin (Mississippi Polymer Tecrono) containing phenylene and benzoylphenylene as structural units is added to 800.0 g of polycarbonate resin (Teijin Chemicals, Panlite L1225-L) obtained from 2,2-bis (4-hydroxyphenyl) propane. 200.0 g of Gmax (Parmax-1201 Krum) was added and mixed uniformly. Subsequently, such a composition was melt-kneaded while degassing at a cylinder temperature of 280 ° C. using a vented twin-screw extruder [KTX-46 manufactured by Kobe Steel Co., Ltd.] to obtain thermoplastic resin composition pellets. Table 1 shows the glass transition temperature, MVR, and flexural modulus of the pellet. After the pellets were dried at 120 ° C. for 5 hours, a 120 mmφ and 1.2 mm thick disc shape was formed by using an injection molding machine [M35B-D-DM manufactured by Meiki Seisakusho Co., Ltd.] with a surface roughness of 0.01 μm. The mirror substrate was injection molded. The arithmetic average roughness (Ra) of the obtained substrate surface was measured using a surf coder SE1100 manufactured by Kosaka Laboratory. The results are shown in Table 1.

[Example 2]
A thermoplastic resin composition pellet was obtained in the same manner as in Example 1 except that 400.0 g of polyphenylene resin (Parmax-1201 Krum) was added to 600.0 g of polycarbonate resin (Panlite L1225-L). Glass transition temperature, MVR, and flexural modulus were measured. Further, a substrate was prepared in the same manner as in Example 1, and the arithmetic average roughness (Ra) of the substrate surface was measured. Table 1 shows the measured glass transition temperature, MVR, flexural modulus, and arithmetic average roughness (Ra).

[Example 3]
A thermoplastic resin composition pellet was obtained in the same manner as in Example 1 except that 600.0 g of polyphenylene resin (Parmax-1201 Krum) was added to 400.0 g of polycarbonate resin (Panlite L1225-L). Glass transition temperature, MVR, and flexural modulus were measured. Further, a substrate was prepared in the same manner as in Example 1, and the arithmetic average roughness (Ra) of the substrate surface was measured. Table 1 shows the measured glass transition temperature, MVR, flexural modulus, and arithmetic average roughness (Ra).

[Example 4]
A thermoplastic resin composition pellet is obtained in the same manner as in Example 1 except that 800.0 g of polyphenylene resin (Parmax-1201 Krum) is added to 200.0 g of polycarbonate resin (Teijin Chemicals, Panlite L1225-L). The glass transition temperature, MVR, and flexural modulus of the pellet were measured. Further, a substrate was prepared in the same manner as in Example 1, and the arithmetic average roughness (Ra) of the substrate surface was measured. Table 1 shows the measured glass transition temperature, MVR, flexural modulus, and arithmetic average roughness (Ra).

[Comparative Example 1]
A thermoplastic resin composition pellet was obtained in the same manner as in Example 1 except that the polycarbonate resin (Panlite L1225-L) was used, and the glass transition temperature, MVR, and flexural modulus of the pellet were measured. Further, a substrate was prepared in the same manner as in Example 1, and the arithmetic average roughness (Ra) of the substrate surface was measured. Table 1 shows the measured glass transition temperature, MVR, flexural modulus, and arithmetic average roughness (Ra).

[Comparative Example 2]
A thermoplastic resin composition pellet was obtained in the same manner as in Example 1 except that a polyphenylene resin (Parmax-1201 Krum) was used, and the glass transition temperature, MVR, and flexural modulus of the pellet were measured. Further, a substrate was prepared in the same manner as in Example 1, and the arithmetic average roughness (Ra) of the substrate surface was measured. Table 1 shows the measured glass transition temperature, MVR, flexural modulus, and arithmetic average roughness (Ra).

[Comparative Example 3]
A thermoplastic resin composition as in Example 1 except that 250.0 g of glass fiber (manufactured by Nippon Electric Glass Co., Ltd.) having a fiber diameter of 13 microns was added to 1000.0 g of polycarbonate resin (Panlite L1225-L). A pellet was obtained, and the glass transition temperature, MVR, and flexural modulus of the pellet were measured. Further, a substrate was prepared in the same manner as in Example 1, and the arithmetic average roughness (Ra) of the substrate surface was measured. Table 1 shows the measured glass transition temperature, MVR, flexural modulus, and arithmetic average roughness (Ra).

Claims (3)

A polycarbonate resin obtained from 2,2-bis (4-hydroxyphenyl) propane , and at least one structural unit selected from the group consisting of 1,4-phenylene, 1,3-phenylene and 1,2-phenylene (A ), 1,4- (benzoylphenylene), and 1,4- (4′-phenoxybenzoylphenylene), at least one structural unit (B), A thermoplastic resin composition comprising a polyphenylene resin having a molar ratio with the unit (B) of (A) :( B) = 1: 99 to 99: 1, wherein the total weight of the composition is 100 parts by weight. composed of a thermoplastic resin composition comprising 20 to 80 parts by weight of the polyphenylene resin to injection molding from a molding material satisfying the following (i) and (ii) The injection molded article arithmetic average roughness (Ra) of the surface is 0.5μm or less.
(I) a glass transition temperature of 120 ° C. to 180 ° C. der Rukoto of the molding material
(Ii) The bending elastic modulus measured according to ISO 178 using a test piece obtained by injection-molding a molding material is 2,700 MPa to 8,000 MPa. Polyphenylene resin is a ratio molar ratio of units in the total binding repeating units (A) and unit (B) (A) :( B ) = 10: 90~90: injection of claim 1 wherein in the range of 10 Molding.   The molding material composed of the thermoplastic resin composition according to claim 1 is injection-molded at a cylinder temperature of 260 ° C to 400 ° C and a mold temperature of 60 ° C to 140 ° C to obtain an arithmetic average roughness (Ra) of the surface. A method for producing an injection-molded product, characterized in that an injection-molded product having a thickness of 0.5 μm or less is obtained.