JP3390514B2 - Aromatic polycarbonate resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an aromatic polycarbonate resin composition. More specifically, it relates to an aromatic polycarbonate resin composition excellent in blow moldability without impairing transparency.

[0002]

2. Description of the Related Art Conventionally, aromatic polycarbonate resins have been excellent in transparency, heat resistance and impact resistance. Therefore, many of them have been melt-molded by injection molding, compression molding, extrusion molding, blow molding or the like. It is used for purposes.

Particularly in recent years, the stretch blow molding method has been attracting attention as a method for inexpensively obtaining a large bottle molded product. In order to obtain a large-sized bottle molded product having a uniform wall thickness by the stretch blow molding method, the material is required to have less drawdown due to its own weight when the preform is heated. However, since the aromatic polycarbonate resin has a large drawdown due to its own weight when the preform is heated, it is difficult to obtain a uniform thick molded product by blow molding, and particularly in the case of a large bottle molded product, molding is difficult.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to obtain an aromatic polycarbonate resin composition having improved blow moldability without impairing transparency. As a result of intensive studies aimed at achieving the above object, the present inventors have found that an aromatic polycarbonate resin having a viscosity average molecular weight of 10,000 to 40,000 has a viscosity average molecular weight of 150,000 to
With 1,000,000 polystyrene resin,
Surprisingly, it was clarified that a composition having good blow moldability could be obtained without impairing transparency, and further studies were conducted to complete the present invention.

[0005]

The present invention relates to (A) 100 parts by weight of an aromatic polycarbonate resin having a viscosity average molecular weight of 10,000 to 40,000 (B) a viscosity average molecular weight of 150,000 to 1,000. The present invention relates to an aromatic polycarbonate resin composition for blow molding, which comprises 0.5 to 10 parts by weight of 1,000 polystyrene resin.

The aromatic polycarbonate resin used as the component (A) can be produced by reacting a dihydric phenol with a carbonate precursor. Typical examples of the dihydric phenol include 2,2-bis (4-hydroxyphenyl) propane [bisphenol A], 1,1-bis (4-hydroxyphenyl) ethane and 1,1-bis (4-hydroxy). Phenyl) cyclohexane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-
Bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone Etc. Preferred dihydric phenols are 2,2-bis (4-hydroxyphenyl) alkanes, especially bisphenol A.

As the carbonate precursor, carbonyl halide, carbonate ester, haloformate or the like is used, and specific examples thereof include phosgene, diphenyl carbonate and dihaloformate of dihydric phenol. In producing an aromatic polycarbonate resin,
The above dihydric phenols may be used alone or in combination of two or more. Further, two or more kinds of the obtained aromatic polycarbonate resins may be mixed and used.

The degree of polymerization of the aromatic polycarbonate resin used as the component (A) is generally 10,000 to 40,000, preferably 15,000, expressed as a viscosity average molecular weight.
It is 0 to 30,000. In producing the aromatic polycarbonate having such a molecular weight, an appropriate molecular weight regulator, a catalyst for accelerating the reaction and the like may be used.

The polystyrene resin used as the component (B) may be a commercially available product, and the polymer of the styrene monomer, that is, the repeating unit is [-CH ₂ -CH (C ₆ H ₅ ).
-]. A typical method for synthesizing polystyrene resin is illustrated below. Styrene monomer is AlC
It is synthesized by catalytic dehydrogenation of ethylbenzene by Friedel-Crafts reaction of benzene and ethylene using l ₃ as a catalyst, and the one having a purity of 99% or more is used. The industrial polymerization method of polystyrene is bulk polymerization or suspension polymerization using a radical catalyst. In the bulk polymerization, a small amount of a peroxide catalyst is added to the monomer, and the mixture is heated at 100 to 120 ° C. for 60 to 70 in a polymerization vessel.
% By prepolymerization and then passing through the inside of the polymerization tower to 15
A method of raising the temperature to 0 to 170 ° C. to complete the polymerization is used.

The degree of polymerization of the polystyrene resin used as the component (B) is 150,000 in terms of viscosity average molecular weight.
~ 1,000,000, preferably 200,000-5
It is 0,000. Viscosity average molecular weight (M)
Is determined using the conversion formula represented by ^{[η] = 0.55 × M 0.} 81 ([η]: The intrinsic viscosity measured at 30 ° C. as a solution in toluene). In producing the polystyrene resin having such a molecular weight, an appropriate molecular weight modifier, a catalyst for accelerating the reaction and the like may be used. If the viscosity average molecular weight is less than 150,000, the drawdown is large and no improvement in blow moldability is observed. Further, in order to suppress the drawdown, a large amount of polystyrene resin must be blended and the transparency is impaired. Viscosity average molecular weight is 100
If it is more than 10,000, the dispersion during mixing is poor and the appearance is poor.

The amount of the polystyrene resin compounded is 0.5 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of the aromatic polycarbonate resin comprising the component (A). If the amount of polystyrene resin is less than 0.5 parts by weight, the blow-down is large and the improvement in blow moldability is not observed.
When it exceeds the weight part, the transparency of the molded product is impaired.

The aromatic polycarbonate resin composition of the present invention may be molded as it is or may be further mixed with a dye. By blending a dye, a molded product having an arbitrary color tone can be obtained. Examples of dyes include azo dyes,
Cyanine type dyes, quinoline type dyes, perylene type dyes, etc. can be arbitrarily used as long as they are usually used for thermoplastic resins, and the blending amount thereof decreases transparency if it is too much. It is necessary to adjust the compounding amount according to the purpose while observing the appearance. Further, an effective expression amount of, for example, a stabilizer, a release agent, an ultraviolet absorber, a flame retardant or the like may be added within a range that does not impair the present invention.

Any method may be used to produce the aromatic polycarbonate resin composition of the present invention. For example, a method of thoroughly mixing an aromatic polycarbonate resin, a polystyrene resin, and other additives appropriately using a mixing means such as a V-type blender, and then pelletizing with a vent type uniaxial ruder, aromatic polycarbonate resin, polystyrene resin And other additives are prepared in advance by a powerful means such as a super mixer, and the mixture is generally industrially used such as a method of supplying it from a vent type twin-screw rudder, kneading it, and pelletizing it. The method used is appropriately used.

[0014]

[Examples] Examples will be further described below. In addition,
The stretch blow moldability was measured by the following method when a preform was formed by a molding machine and the preform was heated.

(1) Drawdown property: When a preform molded by a molding machine is heated, the amount of sag (length: mm) due to its own weight after heating is measured. (2) Transparency (total light transmittance): After heating the obtained preform, the mold was clamped and blown to obtain a bottle-shaped molded product having a diameter of 300 mm and a height of 500 mm. The molding conditions at this time are a resin temperature of 300 ° C., a mold temperature of 60 ° C., and a blow air pressure of 15 kgf / cm ² . A part of this molded product is cut out, and a haze meter-NDH-30 manufactured by Nippon Denshoku Industries Co., Ltd.
The total light transmittance at a thickness of 2 mm was measured at 0A.

[Examples 1 to 5, Comparative Examples 1 to 5] Aromatic polycarbonate resin and polystyrene resin in the amounts shown in Table 1 (expressed in parts by weight) were blended in a tumbler in the amounts shown in Table 1 (shown in parts by weight). 2 with a 40mmφ vented extruder
Pelletized at 80 ° C. The obtained pellets were blow molded by a blow molding machine (Nissei ASB-650
SD type) was used to mold a preform, the drawdown property at the time of heating the preform was measured, and the transparency was measured from the obtained molded product. The measurement results are shown in Table 1. The contents of the aromatic polycarbonate resin and polystyrene resin used are as follows.

PC-1; an aromatic polycarbonate resin having a viscosity average molecular weight of 30,000 produced from bisphenol A and phosgene [Panlite K-13, Teijin Chemicals Ltd.]
00-2 PC-2; Aromatic polycarbonate resin produced from bisphenol A and phosgene having an average molecular weight of 28,500 [Panlite K-1285, Teijin Chemicals Co., Ltd.] PC-3; Viscosity produced from bisphenol A and phosgene Aromatic polycarbonate resin having an average molecular weight of 25,000 [Panlite L-1250, Teijin Chemicals Ltd.] PS-1; polystyrene resin [Topolex 580-57U manufactured by Mitsui Toatsu Chemicals, Inc. (viscosity average molecular weight 200,
000)] PS-2; polystyrene resin [Topolex 500 manufactured by Mitsui Toatsu Chemicals, Inc. (viscosity average molecular weight 120,000)
0)]

[0018]

[Table 1]

[0019]

As is clear from Table 1, the composition of the present invention does not impair the transparency, has a small drawdown upon heating the preform, and has a uniform thickness blow-molded product which has been difficult to produce by conventional methods. In particular, large bottle molded products can be easily obtained,
Extremely useful.

Claims (2)

(57) [Claims] 1. (A) viscosity average molecular weight 10,000 to 4
(B) viscosity average molecular weight of 150,000 to 1.0 with respect to 100 parts by weight of an aromatic polycarbonate resin of 50,000
An aromatic polycarbonate resin composition for blow molding, comprising 0.5 to 10 parts by weight of a polystyrene resin of 0,000. 2. A viscosity average molecular weight of 10,000 to 4
(B) viscosity average molecular weight of 150,000 to 1.0 with respect to 100 parts by weight of an aromatic polycarbonate resin of 50,000
A blow-molded product obtained from an aromatic polycarbonate resin composition containing 0.5 to 10 parts by weight of a polystyrene resin of 0,000.