JP2000239513A - Aromatic polycarbonate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition excellent in transparency, rigidity, etc., by including a specific aromatic polycarbonate resin, and a biphenyl compound and/or terphenyl compound in specified proportions. SOLUTION: This composition is obtained by including (A) 100 pts.wt. of an aromatic polycarbonate resin with a viscosity-average molecular weight of 10,000-40,000 [e.g. a polycarbonate resin produced from 2,2-bis(4- hydroxyphenyl)propane(bisphenol A)], (B) 0.01-40 pts.wt. of (i) a biphenyl compound [pref. a compound of formula I (R is H or Cl) or the like] and/or (ii) a terphenyl compound (e.g. an o-terphenyl compound of formula II, m-terphenyl compound of formula III), and, as necessary (C) 0-20 pts.wt. of a polycaprolactone with a number-average molecular weight of 2,000-100,000.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an aromatic polycarbonate resin composition. For more information, see Transparency,
OA equipment and automotive parts that are required to have high rigidity, transferability of the mold cavity surface unevenness to the product surface (hereinafter sometimes simply referred to as “transferability”), and low warpage and sink of molded products. The present invention relates to an aromatic polycarbonate resin suitably used for manufacturing optical disk substrates, transparent films and the like.

[0002]

2. Description of the Related Art Conventionally, aromatic polycarbonate resins are excellent in transparency, impact resistance, heat resistance and the like, and the molded products obtained are also excellent in dimensional stability. It has been widely used as a raw material resin for manufacturing parts or precision molded products such as optical disk-related parts. In addition, since aromatic polycarbonate resins are excellent in moldability, molding methods for producing these molded articles may be injection molding, extrusion molding, blow molding, etc., which are known as molding techniques for thermoplastic resins. Can be.

However, since molded articles made of aromatic polycarbonate resin alone have lower rigidity than products made of metal or glass, additives such as glass fiber and inorganic filler are added to the base resin for the purpose of improving the rigidity. Has been attempted. In this case, it is common to add 20 parts by weight or more to 100 parts by weight of the aromatic polycarbonate resin. However, when an additive such as the above-mentioned inorganic filler is blended, the refractive index of the additive is different from the refractive index of the aromatic polycarbonate resin, so that there is a defect that transparency, which is a major feature of the aromatic polycarbonate resin, is impaired. It is known to add, for example, polycaprolactone in order to improve the transparency of the aromatic polycarbonate resin (see JP-A-6-228424), but a sufficient effect is exhibited when the amount of the inorganic filler is increased. Not done.

[0004] Additives such as the above-mentioned inorganic fillers often emerge on the surface of a molded product, which causes poor appearance of the molded product and poor transfer of the surface shape of a mold cavity. Furthermore, fibrous additives such as glass fibers have a high anisotropy and are oriented in the flow direction during injection molding, so that there is a disadvantage that warpage is likely to occur particularly in the case of a thin molded product such as an optical disk substrate. . In order to improve the appearance of molded articles containing fibrous additives, (a) a method of adding a plasticizer such as a phthalic acid compound, and (b) a low molecular weight (oligomer) of an aromatic polycarbonate resin And (c) a method of blending polycaprolactone have been proposed and all methods are known to be effective, but all have the drawback that heat resistance is reduced at the same time.

[0005] When an additive such as the above-mentioned inorganic filler is added to the base resin, the rigidity of the base resin is improved. However, the flowability and moldability of the base resin are reduced due to the influence of the additive, and the surface shape of the mold cavity is reduced. There was also a disadvantage that the transferability to the product surface was poor. Until now, an aromatic polycarbonate resin that satisfies simultaneously improving the transferability of the mold cavity surface unevenness to the product surface and reducing the warpage has not yet been realized. That is, a technique for improving the rigidity of the aromatic polycarbonate resin and at the same time improving all of the transparency, moldability, transferability, and the like has not been found yet.

Conventionally, a transparent substrate of an optical disk such as a compact disk (CD) or a digital versatile disk (DVD) has been manufactured by injection molding using an aromatic polycarbonate resin as a raw material. It is necessary to accurately transfer the fine irregularities on the surface of the mold cavity, such as grooves and grooves, to the surface of the molded product. However, in order to increase the signal density, it is necessary to reduce the thickness of the substrate itself and increase the signal density on the substrate surface. In order to increase the signal density on the substrate surface, it is necessary to increase the depth of the pits and grooves and to reduce the distance between the pits and grooves.
Such a fine uneven shape in which the depth of the pits or grooves is increased and the distance between the pits and grooves is reduced makes it extremely difficult to transfer the pits and grooves to the substrate surface.

[0007] Techniques for accurately transferring the fine irregularities onto the substrate surface of the molded article (improving the transferability) include (1) a method of setting a high mold temperature during substrate manufacture, and (2) an aromatic compound. A method of lowering the glass transition temperature of the polycarbonate resin,
Etc. are known. However, the method (1) has a drawback that the warpage of the substrate increases when the mold temperature is set high.The method (2) has a drawback that the rigidity of the resin having a low glass transition temperature decreases at the same time. There is a disadvantage that warpage is also increased.

[0008]

Under such circumstances, the present inventors have found that the transparency, rigidity, etc. are excellent, the mold cavity surface unevenness is excellent in transferability to the product surface, and warpage and sink are small. As a result of diligent studies aimed at providing an aromatic polycarbonate resin composition from which a molded article is obtained,
Assuming a composition in which certain additives are blended in the base resin,
The inventors have found that the excellent transparency of the base resin itself is maintained, the rigidity is excellent, the glass transition temperature of the base resin is reduced, and the flowability is improved to improve the transferability, and the present invention has been completed. . The objects of the present invention are as follows. 1. Provided is an aromatic polycarbonate resin composition having excellent transparency, rigidity, and the like, and excellent transferability of a mold cavity surface shape to a product surface during molding. 2. To provide an aromatic polycarbonate resin composition from which a molded product with less warpage and sink is obtained.

[0009]

In order to solve the above-mentioned problems, according to the present invention, the viscosity-average molecular weight is 10,000 to 4%.
Provided is an aromatic polycarbonate resin composition characterized by comprising 0.01 to 40 parts by weight of a biphenyl compound and / or a terphenyl compound in 100 parts by weight of an aromatic polycarbonate resin of 000.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The base resin of the resin composition according to the present invention is an aromatic polycarbonate resin. Aromatic polycarbonate resin is
A polymer or copolymer obtained by a phosgene method of reacting a dihydroxydiaryl compound with phosgene, or a transesterification method of reacting a dihydroxydiaryl compound with a carbonate such as diphenyl carbonate. As a typical example, 2,2-bis (4-
Polycarbonate resins produced from (hydroxyphenyl) propane (bisphenol A).

Examples of the dihydroxydiaryl compound include bisphenol A, bis (4-hydroxydiphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxydiphenyl) butane, 2,2-bis (4-hydroxyphenyl)
Octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxy-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 Bis (hydroxyaryl) alkanes such as -hydroxy-3,5-dichlorophenyl) propane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4′- Of dihydroxydiaryl ethers such as dihydroxydiphenylether, 4,4'-dihydroxy-3,3'-dimethyldiphenylether, 4,4'-dihydroxyphenylsulfide, and 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfide Dihydroxydiaryl sulfides such as 4,4'-dihi Dihydroxydiarylsulfoxides such as droxydiphenylsulfoxide, 4,4′-dihydroxy-3,3′-dimethyldiphenylsulfoxide, 4,4′-dihydroxydiphenylsulfone, 4,4′-dihydroxy-3, 3 '
Dihydroxydiarylsulfones such as -dimethyldiphenylsulfone; These may be used alone or as a mixture of two or more types. In addition, biperazine, dipiperidyl, hydroquinone, resorcin, 4,4′-dihydroxydiphenyl, and the like may be used in combination.

The viscosity average molecular weight of the aromatic polycarbonate resin as the substrate is in the range of 10,000 to 40,000. If the viscosity average molecular weight is less than 10,000, a molded article having low rigidity and practicality cannot be obtained. If it exceeds 40,000, molding having poor fluidity and excellent transferability of the mold cavity surface shape is performed. Goods are not obtained. The viscosity average molecular weight is
It is preferably from 12,000 to 35,000, and particularly preferably from 13,000 to 30,000.
In the present invention, the viscosity average molecular weight (M) is defined as the intrinsic viscosity (η) obtained using an Ostwald viscometer using methylene chloride as a solvent, and the following Schnell viscosity equation, that is, (η) = 1. 23 × 10 ⁻⁵ M ^0.85 .

The aromatic polycarbonate resin composition according to the present invention comprises the above aromatic polycarbonate resin and a biphenyl compound and / or a terphenyl compound. When a biphenyl compound and / or a terphenyl compound is added to an aromatic polycarbonate resin, rigidity is improved while maintaining excellent transparency of the base resin, and more surprisingly, the glass transition temperature of the base resin is lowered. This also has the effect of improving the transferability during molding, and the mold cavity surface shape can be accurately transferred to the product surface.

The biphenyl compound is a compound in which two benzene rings are bonded, and may have a substituent such as a chlorine atom, and preferably has a structure represented by the following structural formula [I]. . The terphenyl compound is a compound having a structure in which three benzene rings are bonded, and may have a substituent such as a chlorine atom, and preferably includes an ortho terphenyl compound and a meta terphenyl compound. The orthoterphenyl compound is preferably a compound represented by the following structural formula [II], and the metaterphenyl compound is preferably a compound represented by the following structural formula [I]
II]. In the structural formulas [I] to [III], R is a hydrogen atom or a chlorine atom, preferably a hydrogen atom.

[0015]

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[0016]

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[0017]

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Particularly preferred among terphenyl compounds are metaterphenyl compounds. The reason why the meta type is particularly effective is unknown, but it is presumed that the interaction due to the molecular arrangement between the meta type triphenyl compound and the aromatic polycarbonate resin as the base resin, and the plasticizing effect increase. .

Regarding the interaction between the aromatic polycarbonate resin of the base resin and the biphenyl compound and / or terphenyl compound, the resin composition according to the present invention in which the biphenyl compound and / or terphenyl compound is blended with the base resin is at room temperature. Although the rigidity is high at temperatures above 100 ° C, the interaction between the base resin and the additive is relaxed and the additive exerts a plasticizer effect. It has been observed to improve. For example, an aromatic polycarbonate resin having a viscosity average molecular weight of 16,000 has a flexural modulus of 22,000.
Although it is about kgf / cm ² , when the resin composition is prepared by mixing 1 part by weight of the metaterphenyl compound, the flexural modulus of the resin composition becomes as high as about 25,500 kgf / cm ² .

Although the glass transition temperature of the aromatic polycarbonate resin is about 140 to 150 ° C., the resin composition according to the present invention in which the biphenyl compound and / or the terphenyl compound is blended with the base resin, has a reduced amount of these compounds. The glass transition temperature decreases accordingly. For example, when 1 part by weight of a metaterphenyl compound is mixed with an aromatic polycarbonate resin, the glass transition temperature decreases by about 7 ° C. The decrease in the glass transition temperature of the resin composition has the same effect as when the mold temperature is set high, and the transferability of the mold cavity surface to the product surface is improved.

The above-mentioned biphenyl compound and / or terphenyl compound are each independently used for the base resin,
Alternatively, they can be blended as a mixture thereof.
The compounding amount of the biphenyl compound and / or terphenyl compound with respect to the base resin is selected in the range of 0.01 to 40 parts by weight per 100 parts by weight of the aromatic polycarbonate resin. When the amount is less than 0.01 part by weight, the effect of improving rigidity and lowering the glass transition temperature is not remarkable.
If the amount is more than 0 parts by weight, the effect is saturated and the transparency is lowered. The compounding amount of the biphenyl compound and / or the terphenyl compound is preferably 0.05 to 30 parts by weight, and particularly preferably 0.01 to 20 parts by weight.

When the biphenyl compound and / or the terphenyl compound is chlorinated, the chlorine content in the biphenyl compound and the terphenyl compound is preferably more than 20% by weight.
It is in the range of 0 to 70% by weight.

In order to lower the glass transition temperature of the aromatic polycarbonate resin composition according to the present invention and further improve the moldability and transferability, besides blending a biphenyl compound and / or a terphenyl compound with the base resin, It is preferable to blend polycaprolactone having a number average molecular weight of 2,000 to 100,000, preferably 3,000 to 50,000. The amount of polycaprolactone is 0
It is selected in the range of ~ 20 parts by weight. Among them, the preferred amount is in the range of 0.1 to 10 parts by weight. Here, the number average molecular weight of polycaprolactone means a value measured by a method for obtaining a number average molecular weight in terms of polystyrene by a GPC method.

The aromatic polycarbonate resin composition according to the present invention may contain, if necessary, a flame retardant, a flame retardant auxiliary, a coloring agent, a plasticizer, a lubricant, a heat stabilizer, as long as the object of the present invention is not impaired. An antistatic agent, a release agent, an ultraviolet absorber and the like can be added. In order to prepare the aromatic polycarbonate resin composition according to the present invention, a predetermined amount of a biphenyl compound and / or a terphenyl compound, and if necessary, polycaprolactone and the above-mentioned various additives are weighed into the aromatic polycarbonate resin. A method in which the mixture is mixed by a mixer such as a V-type blender, and the obtained mixture is melted and kneaded by an extruder to form pellets.

The aromatic polycarbonate resin composition according to the present invention is required to have transparency, high rigidity, transferability of a mold cavity surface shape at the time of molding, and low warpage and sink of a molded product. It can be suitably used as a raw material resin for manufacturing automotive parts, optical disk substrates, transparent films and the like.

[0026]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following description examples unless it exceeds the gist.

The aromatic polycarbonate resin used in the examples described below has a viscosity average molecular weight of 16,000.
Polycarbonate for optical disks (NOVAREX7020AD manufactured by Mitsubishi Engineering-Plastics Corporation)
2), the additives biphenyl, metaterphenyl and orthoterphenyl were manufactured by Tokyo Chemical Industry Co., Ltd., and polycaprolactam was one having an average molecular weight of 10,000 (Placcel H-1 manufactured by Daicel Chemical Co., Ltd.). It is a chopped strand (chopped strand ECR, manufactured by Asahi Fiber Glass Co., Ltd.).

[Examples 1 to 7, Comparative Examples 1 to 3] Based on 100 parts by weight of the aromatic polycarbonate resin,
The additives were weighed and blended in the proportions (parts by weight) described in Table 1 and mixed with the base resin by a tumbler,
The obtained mixture was melted and kneaded by a 40 mmφ vent type extruder at a cylinder temperature of 270 ° C. to form a pellet. Using the obtained pellet as a raw material, a test piece was prepared using an injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., model: SG75) under the conditions of a cylinder temperature of 290 ° C and a mold temperature of 90 ° C. Various physical properties of the obtained test pieces were evaluated by the methods described below, and the results are shown in Table 1.

(1) Flexural modulus: Measured according to ASTM D-790. (2) Glass transition temperature: DSC (manufactured by Seiko, model: S
SC-5000), the pellets were heated at a rate of 10 ° C./min from room temperature under a nitrogen stream, and the inflection point was defined as the glass transition temperature. (3) Total light transmittance: Measured according to JIS K-7105 on a disc-shaped test piece having a diameter of 120 mm and a thickness of 1.2 mm.

[0030]

[Table 1]

From Table 1, the following becomes clear. (1) The molded article obtained from the aromatic polycarbonate resin composition (Examples 1 to 7) according to the present invention is compared with the molded article obtained from the aromatic polycarbonate resin alone (Comparative Example 1). The glass transition temperature decreases and the stiffness increases. (2) As the amount of the terphenyl compound added to the base resin increases, the effect of lowering the glass transition temperature becomes remarkable, and the rigidity also improves (Examples 3, 4, 6, and 7).

(3) The resin composition in which polycaprolactone is added to the base resin in addition to the terphenyl compound (Example 5) is higher than the resin composition in which only the terphenyl compound is added (Example 3). The effect of lowering the glass transition temperature is remarkable. (4) On the other hand, the resin composition in which only the glass fiber is blended with the base resin (Comparative Example 2) has an improved rigidity, but has a remarkably reduced light transmittance. In addition, the resin composition in which only polycaprolactone is blended with the base resin (Comparative Example 3) has a lower glass transition temperature but a significantly lower rigidity.

[0033]

The present invention has been described in detail above and has the following particularly advantageous effects, and its industrial utility value is extremely large. 1. The aromatic polycarbonate resin composition according to the present invention provides a molded article having excellent rigidity and transparency that cannot be obtained with a conventional aromatic polycarbonate resin.
A It can be widely used as a raw material resin for manufacturing precision molded products such as equipment housing parts, automobile parts, and optical disk-related parts. 2. Since the aromatic polycarbonate resin composition according to the present invention has a lower glass transition temperature than that of the aromatic polycarbonate resin alone, the transferability of the fine irregularities of the mold cavity surface to the molded product surface is improved, and particularly, the optical disc. It is suitable as a molding material for precision molded products such as.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Hiroyoshi Maruyama 5-6-1 Higashi-Hachiman, Hiratsuka-shi, Kanagawa F-term in the Technology Center of Mitsubishi Engineering-Plastics Co., Ltd. FD060 FD090 FD100 FD130 FD160 FD170 GN00 GP00

Claims (4)

[Claims] (1) a viscosity average molecular weight of 10,000 to 40,
000 aromatic polycarbonate resin 100 parts by weight,
Characterized in that a biphenyl compound and / or a terphenyl compound is compounded in an amount of 0.01 to 40 parts by weight,
Aromatic polycarbonate resin composition. 2. The aromatic polycarbonate resin composition according to claim 1, wherein the terphenyl compound is an orthoterphenyl compound or a metaterphenyl compound. 3. The biphenyl compound is a compound represented by the following structural formula [I], and the triphenyl compound is a compound represented by the following structural formula:
Orthoterphenyl represented by [II] or the following structural formula [I
2. The aromatic polycarbonate resin composition according to claim 1, which is metaterphenyl represented by the formula [II], and is a simple substance or a mixture thereof. Embedded image Embedded image Embedded image (In the structural formulas [I] to [III], R represents a hydrogen atom or a chlorine atom.) 4. The method according to claim 1, wherein 0 to 20 parts by weight of polycaprolactone having a molecular weight of 2,000 to 100,000 is blended with respect to 100 parts by weight of the aromatic polycarbonate resin. Item 10. The aromatic polycarbonate resin composition according to item 1.