JP3217862B2 - Aromatic polycarbonate resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an aromatic polycarbonate resin composition . More specifically, the present invention relates to an aromatic polycarbonate having excellent fluidity that cannot be obtained with a conventional polycarbonate while maintaining impact resistance.
The present invention relates to a resin composition .

[0002]

2. Description of the Related Art Polycarbonate is an engineering plastic having excellent impact resistance, transparency and dimensional stability. However, polycarbonate is disadvantageous in that it has poor fluidity, and it has been difficult to injection-mold precision parts and thin objects. In order to improve fluidity, it is necessary to increase the molding temperature and the mold temperature. For this reason, there have been problems that the molding cycle is lengthened, the molding cost is increased, and the polycarbonate is deteriorated during molding.

In order to improve the fluidity, there is a method of reducing the weight average molecular weight of the polycarbonate. However, the polycarbonate obtained by this method has a drawback that the impact resistance is greatly reduced and the solvent resistance is deteriorated. On the other hand, there has been provided a method of improving flowability by mixing polycarbonates having different molecular weights to broaden the molecular weight distribution (US Pat. No. 316).
6606, JP-A-56-45945).

In these methods, a polycarbonate resin composition having a non-Newtonian fluidity and a large die swell is used.
Things are obtained. But these polycarbonates
The resin composition has a lower fluidity under low shear stress than that having a normal molecular weight distribution. The fluidity under high shear stress is comparable to that with normal molecular weight distribution. That is, these polycarbonate resin compositions have non-Newtonian fluidity (the ratio of fluidity under high shear stress and low shear stress is large), but the fluidity itself is never better than the conventional one. Did not.

Heretofore, a polycarbonate having excellent fluidity while maintaining impact resistance has not been obtained.

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to an aromatic polycarbonate resin set having excellent fluidity which cannot be obtained with a conventional polycarbonate while maintaining impact resistance.
It is intended to obtain a Narubutsu.

[0007]

Means for Solving the Problems In order to solve the above problems, the present inventors have developed a gel permeation chromatography (hereinafter abbreviated as GPC) of a polycarbonate resin composition.
As a result of examining the relationship between the weight average molecular weight, the molecular weight distribution, the molecular weight at the peak of GPC, and the low molecular weight part and the weight ratio of the high molecular weight part, the polycarbonate resin composition having a specific range was examined . It was found for the first time that the above problems were solved, and the present invention was reached.

That is, the present invention provides: (1) a weight average molecular weight of 25,000 to 35,000, (2) a molecular weight distribution (Mw / Mn) of 3.0 to 4.0 (where Mw and Mn represent a weight average molecular weight and a number average molecular weight, respectively), 3) The molecular weight of the peak top of the gel permeation chromatograph is 12000 to 17000, and (4) the aromatic polycarbonate having a molecular weight of 100000 or more.
The ratio with respect to the entire carbonate resin composition is 3.5 to 7.0.
(5) aromatic polycarbonate having a molecular weight of 2000 or less
Over preparative percentage of the total resin composition is 3.5 wt% or less, two or more kinds of different molecular weight-fang, characterized in that
Aromatic polycarbonate consisting of aromatic polycarbonate
1. a resin composition ; Melt index ratio (MIR) is 16 or more (however, MIR =
MI value at a temperature of 280 ° C. and a load of 21.6 kg / temperature 28
0 ° C., MI value at a load of 2.16 Kg), two or more aromatic polycarbonates having different molecular weights.
( 1 ) An aromatic polycarbonate resin composition according to ( 1 ), comprising:

The aromatic polycarbonate has a repeating unit represented by the following formula (1).

[0010]

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Here, Ar ¹ represents a divalent aromatic residue, for example, phenylene, naphthylene, pyridylene and those represented by the following formula (II). —Ar ² —Y—Ar ³ (II) wherein Ar ² and Ar ³ are each an arylene group, for example, phenylene, naphthylene, biphenylene,
Represents a group such as pyridylene, and Y represents an alkylene group or a substituted alkylene group represented by the following formula (2).

[0012]

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(Wherein R ¹ , R ² , R ³ and R ⁴ are each a hydrogen atom, a lower alkyl group, a cycloalkyl group, an aryl group or an arylalkyl group, and even if substituted with an alkoxy group, good .K is an integer of 3 to 11, the hydrogen of the methylene group may be substituted with a hydrocarbon group having 1 to 5 carbon atoms.)] the Ar ¹ is (II
I) It may contain the structure represented by the formula.

-Ar ² -Z-Ar ^3- (III) wherein Ar ² and Ar ³ are the same as above, and Z is a mere bond or -O-, -CO-, -S -, - SO ₂ -,
-CO _2- , -CON (R ¹ )-(R ¹ is as defined above)
And the like. Further, at least one hydrogen atom in such an arylene group (Ar ² , Ar ³ ) is not substituted with another substituent such as a lower alkyl group, a lower alkoxy group, a phenyl group, and a phenoxy group. Group, vinyl group, cyano group, ester group, amide group,
It may be substituted by a nitro group or the like.

Specific examples of Ar ¹ include those having the structures shown in the following chemical formulas (3) and (4).

[0016]

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[0017]

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(Wherein R ⁵ and R ⁶ are a hydrogen atom, a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxy group having 1 to 4 carbon atoms, a cycloalkyl group or a phenyl group, respectively. ^May be the same or different from each other, m and n are integers of 1 to 4, and when m is 2 or more, R ⁵ may be different;
When n is 2 or more, R ⁶ may be different from each other. R ^26, R ²⁷ R ²⁸ and R ²⁹ are each a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group of 5 to 8 carbon atoms, a an aryl group having 6 to 12 carbon atoms. Among them, Ar ¹ having a structure represented by the following formula 5 is preferable because of its good fluidity and impact resistance. Further, Ar ¹
Particularly preferred are those having the structure of the following chemical formula 6, and the range where the fluidity and impact resistance are particularly good is when the material having the structure of the chemical formula 6 is contained in an amount of 85% by weight or more.

[0019]

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[0020]

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G of the polycarbonate resin composition of the present invention
The relationship between the PC measurement results and the fluidity and impact resistance was examined in detail. When all of the following five requirements were satisfied, it was found that a polycarbonate resin composition having excellent fluidity was obtained while maintaining impact resistance.

The five requirements are weight average molecular weight (hereinafter referred to as M
w), molecular weight distribution (hereinafter abbreviated as Mw / Mn), peak top molecular weight of gel permeation chromatography (hereinafter abbreviated as GPC), ratio of molecular weight 100000 or more determined by GPC, molecular weight 2 determined by GPC
000 or less. Mw is 25000-3500
It must be in the range of 0 (Mw was measured by GPC). When Mw is less than 25,000, the fluidity is improved, but the impact resistance is greatly reduced, which is not preferable.
If Mw exceeds 35,000, the fluidity decreases, which is not preferable.

The molecular weight distribution (hereinafter abbreviated as Mw / Mn) was measured by GPC. Mw / Mn needs to be in the range of 3.0 to 4.0. If it is less than 3.0, both fluidity and impact resistance decrease, which is not preferable. If it exceeds 4.0, the ratio of the low molecular weight portion increases, and the solvent resistance decreases, which is not preferable. The molecular weight at the top of GPC is
It needs to be in the range of 12000 to 17000. If the molecular weight at the peak top is less than 12,000, the impact resistance is undesirably reduced. If it exceeds 17000, the fluidity decreases, which is not preferable.

Molecular weight 100 determined from GPC integral curve
The ratio of the 000 or more parts to the whole is 3.5 to 7.0.
It must be in weight percent. If it is less than 3.5% by weight, the impact resistance is undesirably reduced. If it exceeds 7.0% by weight, the fluidity decreases, which is not preferable. Aromatic polycarbonate in a portion having a molecular weight of 2,000 or less determined from an integral curve of GPC
It is necessary that the proportion to the entire carbonate resin composition is 3.5% by weight or less. If it exceeds 3.5% by weight,
Impact resistance and solvent resistance are undesirably reduced.

For the first time, an aromatic polycarbonate resin composition that satisfies all of the above-mentioned conditions has achieved unprecedented excellent fluidity while maintaining impact resistance. Furthermore, the aromatic polycarbonate resin composition of the present invention
The product has a melt index ratio (MI
R) is preferably 16 or more. MIR = load 2
MI value at 1.6 kg / MI value M at load 2.16 kg
When the IR is less than 16, the fluidity under a high shear stress decreases, which is not preferable (however, MI is not higher than ASTM 12
38-73, measured at 280 ° C).

The aromatic polycarbonate resin of the present invention
The melt index (MI) of the fat composition is MIR of 1
As long as it is 6 or more, it is not particularly limited,
2. The melt index (MI) value measured at 2.16 kg is logMI ≧ −6.70 × 10 ⁻⁵ × Mw + 2.93.
Is preferably within the range. In the conventionally obtained polycarbonate, logMI ≦ −6.70 × 10 ⁻⁵
It has only a low fluidity in the range of × Mw + 2.80. The polycarbonate resin composition of the present invention has excellent fluidity even under low shear stress.

The aromatic polycarbonate resin composition of the present invention
There is no particular limitation on the method of manufacturing the product . For example, when obtained by mixing, polycarbonate obtained by a known phosgene method or melting method is fractionated using a solvent to obtain a polycarbonate having a sharp molecular weight distribution. There is a method for obtaining a polycarbonate resin composition satisfying the requirements of the present invention by combining several kinds of these polycarbonates having different molecular weights.

[0028] Further, if obtained by polymerization, for example, phosgene method, first polymerizing the high molecular weight polycarbonate, polymerizing further one or more different molecular weight polycarbonate in the presence thereof, polycarbonate resin set to meet the requirements of the present invention
There is also a method of obtaining a product . Whatever the method of the present invention is used, such as mixing, polymerization, etc., is a highly fluid polycarbonate resin composition of the present invention.

Among these production methods, a method of mixing a high-molecular-weight polycarbonate (hereinafter abbreviated as a high-molecular component) obtained by solid-phase polymerization with a low-molecular-weight polycarbonate (hereinafter abbreviated as a low-molecular component) is simply described. The aromatic poly of the present invention
A carbonate resin composition is preferably obtained. The Mw of the polymer component is from 45,000 to 150,000, preferably from 50,000 to 120,000.

The proportion of the portion having a molecular weight of 2,000 or less in the polymer component is preferably 1.0% by weight or less, and the proportion of the terminal hydroxy group in the polymer component is preferably 0.15% by weight or less. Mw of low molecular component is 11000 to 19000
It is preferable that the ratio of the portion having a molecular weight of 2,000 or less in the low molecular component is 5% by weight or less, and the ratio of the terminal hydroxy group in the low molecular component is 0.10% by weight or less.

By mixing 10 to 40 parts by weight of the high molecular weight component and 90 to 60 parts by weight of the low molecular weight component, the aromatic polycarbonate resin composition of the present invention can be easily obtained. A method for synthesizing a polymer component by solid-phase polymerization is described in, for example,
The method described in JP-A-158033 can be used. That is, this is a method in which a prepolymer in an amorphous state is crystallized, and this is subjected to solid-phase polymerization to obtain a polymer component.

The high molecular component and the low molecular component can be used as a mixture of two or more kinds. Further, if it is within a range satisfying the requirements of the present invention, Mw 20000 to 300
It is also possible to add medium molecular components of 00. Mixing of these components can be performed by a known method. It is preferable to perform the mixing by melting using a Banbury mixer, a single screw extruder, or a twin screw extruder.

Alternatively, a method in which a solution of these components is mixed, the solvent is distilled off, and the mixture is melted can be used. The aromatic polycarbonate resin composition of the present invention can be used for a polymer alloy, and a polymer alloy having excellent fluidity and impact resistance can be obtained, which is particularly preferable. As resins suitable as alloys, polyethylene terephthalate, polybutylene terephthalate, modified polystyrene (styrene-maleic anhydride copolymer, styrene-acrylic acid copolymer), styrene-acrylonitrile copolymer, styrene-acrylonitrile-butadiene copolymer , Polyarylate, polyamide, polymethyl methacrylate, polyolefin and the like.

The aromatic polycarbonate resin composition of the present invention
It can be added various known additives to the object. For example, heat stabilizers, release agents, weather stabilizers, flame retardants, pigments, dyes,
Fillers (silica, carbon black, glass fiber, carbon fiber) and the like can be mentioned. As the heat stabilizer, it is preferable to use a phosphorus stabilizer described in JP-A-3-163160, JP-A-3-163161 and the like.

The aromatic polycarbonate resin composition of the present invention
The material has little decrease in fluidity even when glass fiber or carbon fiber is added. When fluidity and high rigidity are required, it is preferable to add these glass fibers and carbon fibers.

[0036]

Next, the present invention will be described in more detail by way of examples, which should not be construed as limiting the present invention. The measuring method is shown below. Molecular weight GPC [RI detector: Shodex RI SE
-51 [Showa Denko KK] Column: TSK-GEL
[Toyo Soda Co., Ltd.], solvent: THF].

It was determined from the calibration curve of the standard monodisperse polystyrene using the reduced molecular weight calibration curve according to the following equation. ^{_{M PC = 0.359M PS 1.0388 (M}} PC molecular weight of the polycarbonate, M _PS is the molecular weight of the polystyrene.) Molecular weight of 100,000 or more, 2,000 or less, and Mw / M
The ratio of n was determined from an integral distribution curve. The terminal hydroxy group is measured by a colorimetric method using titanium tetrachloride [Makromol. Chem. , 88 (196
5) P.I. 215]. Melt Index (MI) Melt Indexer TYPE C-5, manufactured by Toyo Seiki Co., Ltd.
According to ASTM 1238-73 using 059DP, 2
It was measured at 80 ° C. In addition, MI2.16Kg, MI2
1.6 Kg each has a load on the molten resin of 2.1
It shows the number of grams extruded in 10 minutes for 6 kg and 21.6 kg. MIR is represented by the following equation.

Formula MIR = MI value at a load of 21.6 Kg / MI value at a load of 2.16 Kg Izod impact value Measured on a notched molded piece having a thickness of 3 mm according to ASTM D-256. SFD The injection flow pressure was 1000 kg / cm ² , the mold temperature was 90 ° C., the cylinder temperature was 300 ° C., and the spiral flow length with a thickness of 2 mmt was measured. -High molecular components (A, B, C, D), low molecular components (1,
Production of 2) JP-A-1-158033 using 2,2-bis (4-hydroxyphenyl) propane and diphenyl carbonate
Polycarbonates of various molecular weights were produced by the method described in Japanese Patent Application Laid-Open No. H10-260, 1988. The weight average molecular weights of the obtained polycarbonates were 15600 [low molecular component (1)] and 130, respectively.
00 [low molecular component (2)], 63000 [high molecular component (A)], 82000 [high molecular component (B)], 5200
0 [polymer component (C)], 110000 [polymer component (D)], 58100 [polymer component (G)], 1420
0 [low molecular component (5)]. Production of high molecular weight components (E, F) and low molecular weight components (3, 4) JP-A No. 6-1994 using 2,2-bis (4-hydroxyphenyl) propane, para-t-butylphenol and phosgene
Polycarbonates of various molecular weights were produced by the method described in Japanese Patent Application Laid-Open No. 1-238823. The weight average molecular weights of the obtained polycarbonates were 21500 [low molecular component (3)], 15400 [low molecular component (4)] and 8000, respectively.
0 [polymer component (E)] and 62000 [polymer component (F)].

[0039]

Examples 1 to 5 and Comparative Examples 2 to 3 A high molecular weight component and a low molecular weight component were mixed in the composition ratios shown in Table 1, and 15 ppm of bis-nonylphenylhydrogen phosphite and tris- ( 2,4-t-butylphenyl)
220 ppm of phosphite was added and mixed with a Henschel mixer. This mixture was melt extruded at 300 ° C. using a 30 mm φ twin screw extruder and granulated. The physical properties of the granulated product were measured, and the results are shown in Table 1.

[0040]

Comparative Example 1 Mw was determined in the same manner as in the production of the low molecular component (3).
= 21800. To this, a stabilizer was added in the same manner as in Example 1, and 290 was added using a 30 mmφ single screw extruder.
The mixture was melt extruded at ℃ and granulated. The physical properties of the granulated product were measured, and the results are shown in Table 1.

[0041]

Comparative Example 4 A polymer having Mw = 20500 was obtained in the same manner as in Comparative Example 1. This was granulated in the same manner as in Comparative Example 1, and the results of measuring the physical properties of the granulated product are shown in Table 1.

[0042]

Comparative Example 5 A polymer having Mw = 30300 was obtained in the same manner as in Comparative Example 1. This was granulated in the same manner as in Comparative Example 1, and the results of measuring the physical properties of the granulated product are shown in Table 1.

[0043]

[Table 1]

The aromatic polycarbonate resin set of the present invention
Comparison between the product and a single polymer (Example 1 and Comparative Examples 1 and 4)
Comparative Examples 1 and 4 show the performance of the polymers obtained by the known phosgene method. When Mw was reduced (Mw = 21800 to 20500) to increase the fluidity (SFD from 26.3 cm to 31.0 cm), Izod
Impact value is 76Kg · cm / cm to 30Kg · cm / c
m.

On the other hand, in Example 1, the Izod impact value was 78.
It can be seen that the fluidity (SFD: 32.6 cm) is greatly improved while maintaining the large value of Kg · cm / cm.・ Aromatic polycarbonate resin set of the present invention
Comparison with Narubutsu and known compositions (Example 1 and Comparative Examples 2 and 3
The composition of Comparative Example 2 was prepared according to JP-A-56-45945, and the composition of Comparative Example 3 was prepared according to US Pat. No. 3,166,606. Although the compositions of Comparative Examples 2 and 3 have the same Mw as in Example 1, they have very low MI, low SFD, and poor fluidity.

Further, Example 5 is different from Comparative Example 5 in that Izo
d The fluidity (SFD) is greatly improved while maintaining the impact value of 91 kg · cm / cm.

[0047]

The high flow polycarbonate resin according to the present invention
The fat composition has excellent fluidity that cannot be obtained with a conventional polycarbonate, while maintaining impact resistance. Therefore, it is suitable for injection molding of precision parts and thin objects.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 69/00 C08G 64/00-64/42

Claims (2)

(57) [Claims] (1) The weight average molecular weight is 25,000 to 3
5000, (2) molecular weight distribution (Mw / Mn) of 3.0 to 4.0 (where Mw and Mn represent weight average molecular weight and number average molecular weight, respectively), (3) peak top of gel permeation chromatograph (1) an aromatic polycarbonate having a molecular weight of 12,000 to 17000;
The ratio with respect to the entire carbonate resin composition is 3.5 to 7.0.
(5) aromatic polycarbonate having a molecular weight of 2000 or less
Over preparative percentage of the total resin composition is 3.5 wt% or less, two or more kinds of different molecular weight-fang, characterized in that
Aromatic polycarbonate consisting of aromatic polycarbonate
Resin composition . 2. A melt index ratio (MIR) of 16
(However, MIR = temperature 280 ° C., load 21.6K
MI value in g / M at a temperature of 280 ° C. and a load of 2.16 Kg
Two or more molecular weight of the different, which is a I value)
The aromatic polycarbonate resin composition according to claim 1, comprising an aromatic polycarbonate.