JP3019196B2 - Polycarbonate plate injection molding - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate-like injection molded article of an amorphous polycarbonate resin having excellent dimensional accuracy. More specifically, the present invention is characterized in that flake-like glass flakes or a glass flake and a reinforcing filler are blended with an amorphous polycarbonate resin, and that the glass flakes are dispersed and contained little warping and molding shrinkage. The present invention relates to a plate-like injection-molded article having a significantly improved coefficient of expansion and linear expansion coefficient and excellent mechanical properties, appearance, and colorability. 2. Description of the Related Art In recent years, in the fields of automobiles, office equipment, electric appliances and the like, parts thereof, particularly a part of sheet metals, have been manufactured using engineering resin products for the purpose of weight reduction, energy saving and cost reduction. Alternatives have been attempted, and as a result, the demand for engineering resins, especially those reinforced with toughening agents, has increased. For example,
Polyamide resin, polyester resin, which is a crystalline resin,
Polyacetal resin mixed with glass fiber to improve heat resistance and rigidity, non-crystalline resin polycarbonate resin, polyphenylene ether resin, AB
A resin composition in which heat resistance and rigidity are improved by blending glass fiber with S resin has been proposed. However, these resin compositions containing fibrous reinforcing agents, for example, glass fibers, have good rigidity, heat resistance, appearance, and colorability, but the glass fibers have directionality. Therefore, when a plate-like molded product is manufactured by injection molding, there is a disadvantage that the molded product is warped and has anisotropy of a linear expansion coefficient (ratio of a linear expansion coefficient in a flow direction and a perpendicular direction). . These warpage and anisotropy of linear expansion coefficient cause deterioration of physical properties and thermal properties for engineering resins intended to replace sheet metal and aluminum die-casting, as well as a large decrease in product value. It is also a factor. Accordingly, in the case of engineering resins filled with a reinforcing agent, various studies have been made on the improvement of the anisotropy of the warpage and the coefficient of linear expansion. Conventionally, for the suppression of the warpage, for example, a thermoplastic resin is filled with a short fiber inorganic filler. Resin composition comprising a blending agent and inorganic particles (Japanese Patent Application Laid-Open No.
No. 35749), a resin composition comprising a solid polymer and a mica material for reinforcement (Japanese Patent Publication No. 49-18615), and a resin composition comprising a polyethylene terephthalate resin, a fibrous reinforcing filler and a glass foil (Japanese Patent Publication No. Sho 60-160). -1722
No. 3), a resin composition comprising a mixture of aromatic polyester and flat glass flakes (Japanese Patent Publication No. 60-17223).
Gazette). However, when these resin compositions are used as a substitute for aluminum die-casting, for example, the objects of energy saving and cost reduction by weight reduction and elimination of secondary processing are achieved, and bending elastic modulus, Izod impact Although it is almost satisfactory in terms of mechanical properties such as strength and heat deformation temperature, dimensional accuracy, for example, warpage, molding shrinkage, improvement in linear expansion coefficient, etc. are not necessarily sufficient, and In addition, the appearance and the coloring are inferior, and the use is inevitably restricted. In particular, in the combination of a crystalline resin and a reinforcing filler, shrinkage due to volume shrinkage and linear expansion is caused by crystallization of the crystalline resin, and these cause molding shrinkage. Since the filler is oriented in the direction of flow of the resin, anisotropy of shrinkage occurs depending on the direction, causing warpage which is generally recognized, and not enough to improve the molding shrinkage and linear expansion coefficient. [0007] Under such circumstances, an object of the present invention is to improve the dimensional stability inherent to polycarbonate and to have excellent mechanical and electrical properties. Another object of the present invention is to provide a plate-shaped injection-molded article having excellent appearance and coloring properties, and in particular, to provide a polycarbonate plate-shaped injection-molded article having extremely excellent dimensional accuracy which is optimal as a substitute for sheet metal. Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to achieve the above object, and as a result, flake-like glass flakes alone or this glass have been added to an amorphous polycarbonate resin. It has been found that the purpose can be achieved by blending flakes and a reinforcing filler up to a predetermined amount with the flakes and injecting pellets produced by a twin-screw extruder, and completed the present invention based on the knowledge. I can do it. That is, the present invention relates to an injection molded article of a pellet produced by a twin-screw extruder, wherein the maximum diameter (L) is 1000 per 100 parts by weight of an amorphous polycarbonate resin.
μm or less, 5 to 150 parts by weight of flaky glass flakes having a ratio (L / D) of maximum diameter (L) to thickness (D) of 5 or more and optionally 50% by weight or less based on the glass flakes. An object of the present invention is to provide a plate-like injection-molded article characterized in that a fibrous reinforcing filler is dispersed. DETAILED DESCRIPTION OF THE INVENTION The amorphous polycarbonate resin used in the molded article of the present invention can be arbitrarily selected from those usually used for injection molding. It can also contain other amorphous thermoplastic resins such as styrenic resins to the extent that they do not detract from the desirable physical properties of polycarbonate. [0011] The glass flakes used in the molded article of the present invention are scaly and have a maximum diameter of 100 after compounding the resin.
0 μm or less, preferably in the range of 1 to 500 μm,
And the aspect ratio (the ratio of the maximum diameter to the thickness) is 5 or more, preferably 10 or more, and more preferably 30 or more. As the glass flakes, commercially available glass flakes can be used as they are, or they may be appropriately pulverized and used as needed when blended with a resin. The glass flake has a maximum diameter of 1000 μm
If the amount exceeds, classification occurs at the time of compounding, uniform dispersion with the resin becomes difficult, and a molded article is spotted,
When the aspect ratio is less than 5, the heat distortion temperature of the molded product is insufficiently improved, and the Izod impact strength is also reduced. The amount of the flaky glass flakes used in the molded article of the present invention is as follows.
5 to 150 parts by weight, preferably 20 to 100 parts by weight
To 100 parts by weight, more preferably 30 to 70 parts by weight. If the amount is less than 5 parts by weight, the improvement of the coefficient of linear expansion becomes particularly insufficient. On the other hand, if it exceeds 150 parts by weight, uniform mixing becomes difficult and the workability and appearance of the molded article are deteriorated. In particular, when the used amount of the glass flake is in the range of 30 to 70 parts by weight, a remarkable improvement in thermal properties, mechanical properties, dimensional accuracy (warpage, molding shrinkage, linear expansion coefficient) and the like is observed. Can be In addition, as the glass flake, for the purpose of improving the affinity with the resin, for example, a glass flake surface-treated with various coupling agents such as a silane-based or a titanate-based can be used. The molded article of the present invention may further contain a granular or short-fiber reinforcing filler in addition to the glass flakes. As such a reinforcing filler, for example, glass fiber, carbon fiber, ceramic fiber, short fiber-based reinforcing filler such as metal fiber,
Inorganic granules such as glass beads can be mentioned, and it is preferable to use these reinforcing fillers together in an amount of 50% by weight or less based on glass flakes. If the ratio of the short fiber reinforcing filler exceeds 50% by weight, dimensional accuracy (warpage, molding shrinkage,
(Linear expansion coefficient) cannot be sufficiently improved, and when the amount of the inorganic particles exceeds 50% by weight, the rigidity is lowered, which is not preferable. In the present invention, the method of blending the amorphous polycarbonate resin and the glass flakes alone or the glass flakes and the granular or short fiber reinforcing filler is not particularly limited, and any method can be used. For example, a method of adding and mixing flaky glass flakes alone or this glass flake and other reinforcing fillers to a non-crystalline polycarbonate resin in a molten state, a non-crystalline polycarbonate resin and glass flakes alone or this glass flake and other Any method can be used as long as it is a commonly used melt mixing method such as a method in which a reinforcing filler is mixed in advance and then melt-mixed. The molded article of the present invention may contain, if desired, a flame retardant such as a halogen or phosphate ester, a flame retardant auxiliary such as antimony trioxide, an antioxidant such as a phenol, phosphorus or hindered phenol. Stabilizers, coloring agents such as titanium oxide and carbon black, lubricants such as metal soaps,
A required amount of a fluidity modifier, a thermoplastic elastomer for reinforcement such as polyester amide, and the like can be contained. The molded article of the present invention comprises a non-crystalline polycarbonate resin in which flaky glass flakes or the glass flakes and a granular or short fibrous reinforcing filler are dispersed and contained. It has a high heat deformation temperature, excellent mechanical properties, little warpage, and improved molding shrinkage and linear expansion coefficient, so that the dimensional accuracy is remarkably improved, and the appearance and colorability are good. Therefore, it is particularly suitably used as an engineering resin as a substitute for sheet metal in automobiles, electric products, office equipment, and the like. EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. The characteristics of the resin molded body were determined using an IS-80AM injection molding machine manufactured by Toshiba Machine Co., Ltd. at a cylinder temperature of 300 ° C. and a mold temperature of 80 ° C. according to the following test method. evaluated. (1) Thermal deformation temperature: ASTM-D648 (2) Flexural modulus: ASTM-D790 (3) Izod impact strength: ASTM-D256, 1 /
4 inch thick notch (4) Mold shrinkage: ASTM-D955, 150 × 15
A 0 × 3 mm flat plate, with a shrinkage ratio of preferably 0.4% or less. (5) Flame retardancy: UL-94, 1/8 inch molded piece used. (6) Warpage: The maximum warpage (mm) is measured using a 150 × 150 × 3 mm flat plate and a gap gauge. The smaller the numerical value, the better the dimensional accuracy. (7) Melt flow rate: Using a melt indexer MX-101A manufactured by Takara Kogyo, the flow rate (g) after holding at 250 ° C. and 2 kg load for 10 minutes was determined. The larger the value, the better the fluidity. (8) Dyeability and gloss: A 150 × 150 × 3 mm flat plate was used and visually judged. (9) Linear expansion coefficient: Using a test piece pre-treated by the method of ASTM-D618 after removing distortion by annealing, the linear expansion coefficient of the resin in the flow direction and the linear expansion coefficient in the direction perpendicular to the flow direction are calculated as follows: AST using a resistance strain gauge
It measured between -35 and 65 degreeC according to the method of MD-696. The anisotropy of the coefficient of linear expansion referred to in the present invention is a value obtained by dividing the coefficient of linear expansion in the perpendicular direction by the coefficient of linear expansion in the flow direction. It can be said that a resin composition having a value closer to 1 has less anisotropy. It is necessary that this anisotropy is 2 or less as an engineering resin for sheet metal replacement. EXAMPLE Panlite K-1 was used as an amorphous polycarbonate resin.
300 (manufactured by Teijin Chemicals Limited) as a stabilizer, Mark AO-
30 (manufactured by Adeka Argus Co., Ltd.) and CEF150A (manufactured by Nippon Sheet Glass Co., Ltd.) as glass flakes at a ratio as shown in Table 1, and a 30φ twin screw extruder (manufactured by Nakatani Machine Co., Ltd.)
Was extruded and kneaded under the conditions of 300 ° C. and a discharge rate of 10 kg / hr to produce pellets, and the physical properties of plate-like bodies obtained by injection molding were determined. Table 1 shows the results. Comparative Examples 1, 2, 4 Polyethylene terephthalate resin (crystal melting point: 265 ° C., 0.4 ° C./kg in 25 ° C. o-chlorophenol) and polybutylene terephthalate resin Toray PBT1401 × 06 as crystalline fibers were used as glass fibers. RES
Using O3-TP68 (manufactured by Nippon Sheet Glass) and CEF048A (manufactured by Nippon Sheet Glass) as glass flakes at a ratio as shown in Table 1, using an AS-30φ twin screw extruder (manufactured by Nakatani Machine Co., Ltd.), 300 ° C, discharge rate 10kg /
The pellets were prepared by extrusion kneading under the conditions of hr, and the physical properties of the plate obtained by injection molding the pellets were determined. Table 1 shows the results. Comparative Examples 3, 5, 6, 7 As an amorphous thermoplastic resin, the intrinsic viscosity was 0.62 (25 ° C.).
Poly (2,6-dimethyl-1,4-) in chloroform
Phenylene) ether, impact-resistant polystyrene resin Stylon QH405 (manufactured by Asahi Kasei Kogyo) and polystyrene resin Styron GP685 (manufactured by Asahi Kasei Kogyo), and triphenyl phosphate (manufactured by Daihachi Chemical) as a flame retardant
Mark AO-30 (manufactured by Adeka Argus) as a stabilizer, RESO3-TP68 (manufactured by Nippon Sheet Glass) as a glass fiber, trading card T006 (manufactured by Toray Industries) as a carbon fiber, and Suzulite Mica 200KI as a flake filler. (Manufactured by Kuraray Co., Ltd.) and glass beads EGB731A (manufactured by Toshiba Barocini) as a spherical filler.
At 280 ° C and a discharge rate of 10 kg using an AS-30 φ twin screw extruder (manufactured by Nakatani Machine Co., Ltd.)
The pellets were prepared by extrusion kneading under the conditions of / hr, and the physical properties of the plate obtained by injection molding the pellets were determined. Table 1 shows the results. [Table 1] As can be seen from Table 1, Comparative Example 1 is unpreferable because of its large warpage, molding shrinkage, linear expansion coefficient and its anisotropy as compared with Examples. Comparative Example 2 is Comparative Example 1
Although the warpage, the molding shrinkage, and the coefficient of linear expansion are considerably improved, the warpage is insufficient because the base is based on a crystalline resin as compared with the examples, which is not preferable. Further, Comparative Example 3 is insufficient in warpage, molding shrinkage, and linear expansion coefficient, and is inferior in appearance gloss as compared with Examples.
Comparative Example 5 is not preferable because the resin is blackish brown and the impact strength and appearance gloss are significantly reduced, although the warpage, the molding shrinkage and the linear expansion coefficient are not inferior to those of the example. In Comparative Example 6, since the glass fiber and the glass beads were mixed and added as compared with the Example, the warpage, the flexural modulus and the molding shrinkage were insufficient, which is not preferable. In Comparative Example 7, warpage, molding shrinkage, coefficient of linear expansion, and appearance gloss were inferior and inadequate, as compared with Example, because glass fiber and carbon fiber were mixed and added.

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 45/00-45/84 C08K 3/40 C08K 7/00-7/28 C08L 69/00

Claims (1)

(57) [Claims] It is an injection molded article of a pellet manufactured by a twin screw extruder, and in 100 parts by weight of an amorphous polycarbonate resin,
A warp characterized in that 5 to 150 parts by weight of flaky glass flakes having a maximum diameter (L) of 1000 μm or less and a ratio (L / D) of the maximum diameter (L) to the thickness (D) of 5 or more are dispersed. A plate-like injection molded article with excellent gloss and no luster. 2. It is an injection molded article of a pellet manufactured by a twin screw extruder, and in 100 parts by weight of an amorphous polycarbonate resin,
5 to 150 parts by weight of flaky glass flakes having a maximum diameter (L) of 1000 μm or less and a ratio (L / D) of maximum diameter (L) to thickness (D) of 5 or more and 50% by weight or less based on the glass flakes A plate-like injection molded article excellent in gloss without warpage, characterized in that a granular or short-fiber reinforcing filler is dispersed.