JPS61241355A - Polycarbonate resin composition - Google Patents

Abstract

PURPOSE:A composition, obtained by incorporating polycarbonate resin with glass short fibers and glass ultrashort fibers in a given proportion, and further adding a small amount of a polylactone, having improved mechanical characteristics and capable of giving molded articles having good gloss and surface appearance. CONSTITUTION:A polycarbonate resin composition obtained by incorporating 100pts.wt. composition consisting of 50-98wt% polycarbonate resin having preferably 10,000-100,000 viscosity-average molecular weight and (B) 50-2wt% total of glass short fibers having 1-10mm average fiber length and (C) glass ultrashort fibers having 0.02-0.5mm average fiber length at 1/3-10/1 weight ratio between the components (B) and (C) with (D) 0.01-5pts.wt., preferably 0.1-2pts.wt. polycaprolactone expressed by the formula (R1 and R2 are H or 1-5C alkyl; x is 2-10; n is 100-2,000) and having preferably 40,000-100,000 number-average molecular weight.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a polycarbonate resin composition, and particularly to a polycarbonate resin composition that has excellent mechanical properties and has a good gloss 9 surface appearance when molded.

(Prior art and problems to be solved by the invention) It has been known that glass fiber-reinforced polycarbonate resins are superior to non-reinforced polycarbonate resins in heat distortion temperature, rigidity, and one-dimensional stability. Anisotropy occurs due to the orientation of glass fibers, which poses a problem in product design.Additionally, if ultra-short glass fibers are placed on short glass fibers and blended, anisotropy and appearance can be improved. ,
On the contrary, there is a problem in that the impact resistance decreases. Therefore, an attempt was made to prevent the decrease in impact resistance by adding polyethylene wax (Japanese Patent Laid-Open No. 57-9404
No. 0) has been made, but it is still not satisfactory, and furthermore, this method has the disadvantage that the resulting molded product has poor gloss.

On the other hand, a composition in which polycaprolactone is blended with polycarbonate resin to improve mold release properties is disclosed in Japanese Patent Application Laid-Open No. 51-584.
No. 57 and Japanese Unexamined Patent Publication No. 51-143058, but no consideration has been given to the mechanical properties.

Therefore, the present inventors have made extensive studies to improve the gloss 9 surface appearance of molded products without impairing the rigidity and impact resistance of glass fiber reinforced polycarbonate resin.

[Means for solving problems]

As a result, by blending short glass fibers and ultrashort glass fibers in a certain ratio, and blending a small amount of polylactone,
The inventors have found a way to achieve the above object and have completed the present invention.

That is, in the present invention, (A) polycarbonate resin 50 to
98% by weight, (B) short glass fibers with an average fiber length of 1.0 to 10 tsuru, and (C) ultrashort glass fibers with an average fiber length of 0.02 to 0.5 tsuru in a total amount of 50 to 2% by weight. , the weight ratio (B) of the glass short fibers (B) and the glass ultrashort fibers (C)
)/(C) is a polycarbonate resin composition characterized in that 0.01 to 5 parts by weight of polylactone is blended to 100 parts by weight of the composition in which (C) is 1/3 to 10/1.

The polycarbonate resin used in the present invention has the following general formula (where 2 is a bond or an alkylene having 1 to 8 carbon atoms,
Alkylidene having 2 to 8 carbon atoms, cycloalkylene having 5 to 15 carbon atoms, cycloalkylidene having 5 to 15 carbon atoms, S
means Oz, SO, O, Co or a group, R means a hydrogen, chlorine or bromine atom or a saturated alkyl group having 1 to 8 carbon atoms, and m represents the number from O to 4. ) It is a polymer having a structural unit represented by:

This polycarbonate resin is prepared by a solvent process, i.e. by the reaction of a dihydric phenol with a carbonate precursor such as phosgene or by the reaction of a dihydric phenol with a carbonate precursor such as phosgene in a solvent such as methylene chloride in the presence of a known acid acceptor 9 molecular weight regulator. It can be produced by transesterification reaction with carbonate precursors such as.

Here, dihydric phenols that can be suitably used include bisphenols, and 2,2-bis(4-hydroxyphenyl)propane (bisphenol A) is particularly preferred. Further, part or all of bisphenol A may be substituted with other dihydric phenol. Examples of dihydric phenols other than bisphenol A include hydroquinone.

4.4'-dihydroxydiphenyl, bis(4-hydroxyphenyl)alkane, bis(4-hydroxyphenyl)cycloalkane, bis(4-hydroxyphenyl)
Compounds like sulfide, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)ether or bis(3,5-dibromo-4-hydroxyphenyl)propane, bis( Mention may be made of halogenated hisphenols such as 3,5-dichloro-4-hydroxyphenyl)propane. These dihydric phenols may be homopolymers or copolymers or blends of two or more dihydric phenols. Furthermore, the polycarbonate resin used in the present invention may be a thermoplastic randomly branched polycarbonate obtained by reacting a polyfunctional aromatic compound with a dihydric phenol and/or a carbonate precursor.

The polycarbonate resin used in the present invention has a viscosity average molecular weight (Mv) from the viewpoint of mechanical strength and moldability.
is preferably from 10,000 to 100,000, particularly preferably from 15,000 to 40,000.

Next, the short glass fibers (B) and the very short glass fibers (C) may be either alkali-containing glass or alkali-free glass, but E glass is particularly preferred. There are no particular restrictions on the diameter of the glass fibers, but those having a diameter of 1 to 20 μm are usually used. Note that in order to increase the affinity with the resin, it is preferable to perform a surface treatment such as silane treatment, borane treatment, or chromium treatment.

Further, the short glass fibers (B) are glass fibers with an average fiber length of 1.0 to 10 days, preferably 1.5 to 6 days, and the ultrashort glass fibers (C) are glass fibers with an average fiber length of 0.02 to 0. The glass fiber is 0.5 mm, preferably 0.03 to 0.3 mm. Here, if the fiber length of the ultrashort glass fibers (C) is shorter than 0.02 m, the impact resistance will decrease, and if it is longer than 0.5 m, the appearance will deteriorate, which is not preferable.

The weight ratio (B)/(C) of the short glass fibers (B) and the very short glass fibers (C) is 1/3 to 10/1, preferably 1/2 to 8/1, more preferably 1/2. A ratio of 1 to 5/1 is suitable. When (B)/(C) is smaller than 1/3, the rigidity decreases greatly, and when it is larger than 10/1, the appearance of the molded product becomes poor, which is not preferable.

The above-mentioned polycarbonate resin (A) and short glass fiber (B
) and glass ultrashort fibers (C) are 50 to 98% by weight of polycarbonate resin (A), preferably 65 to 98% by weight.
95% by weight, short glass fibers (B) and very short glass fibers (C)
) The total amount of (B)+(C) is 50-2% by weight, preferably 35-5% by weight. Here, the total amount of glass fiber (
If B)+(C) exceeds 50% by weight, the resulting molded product will have a poor appearance, and if it is less than 2% by weight, the rigidity will be insufficient, which is not preferable.

Next, the polylactone used in the present invention has the following general formula (where R, Rz is hydrogen or an alkyl group having 1 to 5 carbon atoms, preferably hydrogen or a methyl group, and X is 2
~10, preferably 3-8, and n is 100-20
00, preferably 300-1000. ), and has a number average molecular weight of 40,000 to 1
00000 polycaprolactone (x=5) is particularly preferred.

Regarding the blending amount of polylactone, polycarbonate resin (A), short glass fiber (B) and ultra short glass fiber (
The amount of polylactone is 0.01 to 5 parts by weight, preferably 0.1 to 2 parts by weight, per 100 parts by weight of the above composition consisting of C). If the amount is less than 0.01 part by weight, the effect of improving the gloss and appearance of the molded product will be insufficient, and if it is more than 5 parts by weight, the heat distortion temperature will decrease undesirably.

〔Effect of the invention〕

According to the present invention, a polycarbonate composition can be obtained that gives a molded article excellent in gloss (1), surface appearance, mechanical properties such as impact resistance (9), flexural modulus (9), and good heat resistance. Therefore, this polycarbonate composition is useful as parts for electrical, electronic, optical equipment, etc.

〔Example〕 Next, the present invention will be explained in detail with reference to examples.

Examples 1 to 8 and Comparative Examples 1 to 8 Polycarbonate resin, short glass fibers, ultrashort glass fibers, and polycaprolactone were prepared, mixed in the proportions shown in Table 1, and extruded using an extruder with a cylinder temperature of 300°C. It was pelletized. The following tests were conducted on the obtained composition. The results are shown in Table 1.

Test method Izosod Impact strength (JIS K7110 compliant) Flexural modulus (JIS K7203 compliant) Heat distortion temperature (JIS K7203 compliant)
S K7207 compliant) Glossiness (JIS K7105
Compliant) Surface appearance: Visually evaluated, those with a smooth surface and good appearance were rated as Δ, those with some floating glass fibers were rated Δ, and those with a lot of floating glass fibers were rated ×.

Comparative Example 9 In Example 2, instead of polylactone, polyethylene wax (manufactured by Mitsui Petrochemical Co., Ltd., "Hiwax 40" was used).
The same operations and tests as in Example 2 were performed except that 0PJ) was used. The results are shown in Table 1.

$1 (A) PC resin: Bisphenol A-based polycarbonate resin A: Viscosity average molecular weight 20,000. Manufactured by Idemitsu Petrochemical ■, r
N2200J B: Viscosity average molecular weight 18,000 C: Viscosity average molecular weight 128,000. Manufactured by Idemitsu Petrochemical ■, r
A3000J $2 (B) Short glass fiber: E glass, manufactured by Nippon Electric Glass ■ A: Average fiber length 3 mm, diameter 13 μB: Average fiber length 1.5 mm, diameter 13 μ $3 (C) Glass ultra short fiber :E
Glass, manufactured by Nippon Electric Glass ■ A: Average fiber length 0.04 mm, diameter 9 μ B: Average fiber length 9.2 mm, diameter 9 μ C: Average fiber length 0.01 mm, diameter 9 μ D: Average fiber length 9.7 mm , diameter 9μ $4 (B) / (C): Weight ratio of the above-mentioned (B) short glass fibers and (C) glass ultrashort fibers *5 The following poly-ε-caprolactone (manufactured by Daicel Industries ■) A: Number Average molecular weight: 5oooo, "Plaxel H-4" B: Number average molecular weight: 90,000. r Praxel H-7”

Claims (1)

[Claims] 1. (A) 50 to 98% by weight of polycarbonate resin and (
Consisting of a total of 50 to 2% by weight of B) short glass fibers with an average fiber length of 1.0 to 10 mm and (C) very short glass fibers with an average fiber length of 0.02 to 0.5 mm, the short glass fibers (
Weight ratio (B)/(C) of B) and the glass ultrashort fiber (C)
1. A polycarbonate resin composition characterized in that 0.01 to 5 parts by weight of polylactone is blended to 100 parts by weight of the composition having a ratio of 1/3 to 10/1. 2. The composition according to claim 1, wherein the polylactone is represented by the following general formula. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (Here, R_1 and R_2 are hydrogen or an alkyl group having 1 to 5 carbon atoms, x is 2 to 10, and n is 100 to 200.
It is 0. )