JP3617893B2 - Polycarbonate resin composition with excellent residence heat stability - Google Patents

Description

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【表３】

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【発明の効果】
グリセリンモノエステル化合物を特定量配合してなるポリカーボネート樹脂組成物において、グリセリンモノエステル化合物に含有されるナトリウムを２０ｐｐｍ以下とすることにより、離型性ならびに滞留熱安定性に著しく優れた組成物を得ることができる。これにより、ポリカーボネート樹脂組成物における成形品の大型化、薄肉化を、さらには成形品のデザインの自由度をアップ、表面平滑性の改良、寸法安定性の改良が可能となる。[0001]
[Industrial application fields]
The present invention relates to a polycarbonate resin composition having excellent residence heat stability. More specifically, in a composition comprising a polycarbonate resin and a glycerin monoester compound or such a compound and a phosphorus stabilizer, the residence heat stability is improved by suppressing sodium contained in the glycerin monoester compound. It is related with the polycarbonate resin composition which becomes.
[0002]
[Prior art]
Polycarbonate resin is used as an engineering plastic excellent in transparency, heat resistance, and impact resistance in various fields such as vehicles, light electrical appliances, general equipment, food, and medical.
[0003]
In the molding of polycarbonate resin, excellent releasability is required from the viewpoints of dimensional stability, freedom of molded product shape (design), surface smoothness, and the like. For this reason, the addition of compounds such as beeswax, pentaerythritol tetrastearate, polyethylene wax, montanic acid wax, stearyl stearate and glycerin monoester compounds has been proposed and has already been partially used.
[0004]
[Problems to be solved by the invention]
However, even in a polycarbonate resin composition having improved releasability formed by blending a glycerin monoester compound, like a general polycarbonate resin, it must be molded at a higher temperature from the viewpoint of increasing the size or thickness of a molded product. Therefore, excellent residence heat stability is required.
[0005]
Conventionally, the addition of stabilizers such as phosphorus and phenols has been proposed to improve the residence heat stability of polycarbonate resins, but the improvement effect is not sufficient, and the release property is superior in residence heat stability. There has been a need for a polycarbonate resin composition.
[0006]
[Means for Solving the Problems]
As a result of diligent research in view of such problems, the present inventors reduced the specific elements contained in the glycerin monoester compound blended as a mold release improver, thereby stabilizing the residence heat of the polycarbonate resin composition. The inventors have found that the properties are remarkably improved, and have reached the present invention.
[0007]
That is, the present invention provides 0.01 to 0.8 parts by weight of the glycerol monoester compound (B) or 0.01 to 0.8 parts by weight of the glycerol monoester compound (B) per 100 parts by weight of the polycarbonate resin (A). In the composition formed by blending 0.005 to 0.5 parts by weight of a phosphorus stabilizer (C), the residence heat is characterized in that the sodium contained in the glycerin monoester compound (B) is 20 ppm or less. A polycarbonate resin composition having excellent stability is provided.
[0008]
The polycarbonate resin (A) used in the present invention is a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted, or a transesterification method obtained by reacting a dihydroxydiaryl compound and a carbonate such as diphenyl carbonate. A typical example is a polycarbonate resin produced from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).
[0009]
Examples of the dihydroxydiaryl compound include bisphenol 4-, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2, 2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxyphenyl-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 ( Bis (hydroxyaryl) alkanes such as 4-hydroxy-3,5-dichlorophenyl) propane, 1,1- (4-hydroxyphenyl) cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3 Dihydroxy diaryl ethers such as 3,3'-dimethyldiphenyl ether, dihydroxy diaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3 ' Dihydroxy diaryl sulfoxides such as dimethyldiphenyl sulfoxide, dihydroxy diary such as 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone Sulfone, and the like.
[0010]
These may be used alone or in combination of two or more. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4′-dihydroxydiphenyl, and the like may be used in combination.
[0011]
Furthermore, the above dihydroxyaryl compound and a trivalent or higher phenol compound as shown below may be used in combination.
[0012]
Trihydric or higher phenols include phloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene, 2,4,6-dimethyl-2,4,6-tri- (4 -Hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -ethane and 2,2-bis- [4 4- (4,4'-dihydroxydiphenyl) -cyclohexyl] -propane and the like.
[0013]
The viscosity average molecular weight of the polycarbonate resin is usually 10,000 to 100,000, preferably 15,000 to 35,000. In producing such a polycarbonate resin, a molecular weight regulator, a catalyst and the like can be used as necessary.
[0014]
Examples of the glycerol monoester compound (B) used in the present invention include glycerol monostearate, glycerol monooleate, and glycerol monobehenate. These can be used alone or in combination of two or more. In particular, glycerin monostearate is preferable.
[0015]
The glycerin monoester compound (B) is blended in an amount of 0.01 to 0.8 parts by weight per 100 parts by weight of the polycarbonate resin (A). If it is less than 0.01 parts by weight, the effect of improving the releasability is insufficient. On the other hand, if it exceeds 0.8 parts by weight, the low temperature impact strength and the residence heat stability of the polycarbonate resin composition are impaired, which is not preferable. Especially preferably, it is 0.03-0.2 weight part.
[0016]
Examples of the phosphorus stabilizer (C) used in the present invention include tris (nonylphenyl) phosphite, triphenylphosphite, tris (ethylphenyl) phosphite, tris (butylphenyl) phosphite, and tris (hydroxyphenyl). ) Phosphite, tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylenediphosphonite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di -Compounds such as -phosphite, tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylenephosphonite, tris (2,4-di-t-butylphenyl) phosphite, It can be used by 1 type (s) or 2 or more types.
In particular, tris (2,4-di-t-butylphenyl) phosphite and tetrakis (2,4-di-t-butylphenyl) -4,4′-biphenylene diphosphonite are preferable.
[0017]
The phosphorus stabilizer (C) is blended in an amount of 0.005 to 0.5 parts by weight per 100 parts by weight of the polycarbonate resin. If it is less than 0.005 parts by weight, the residence heat stability is inferior, and if it exceeds 0.5 parts by weight, the low-temperature impact resistance is inferior. Especially preferably, it is 0.03-0.1 weight part.
[0018]
In the glycerol monoester compound (B) used in the present invention, the amount of sodium contained in such a compound is important. That is, sodium contained in the glycerin monoester compound (B) must be 20 ppm or less. If it exceeds 20 ppm, the residence heat stability is not improved, which is not preferable. In particular, 10 ppm or less is preferable.
Sodium contained in the glycerin monoester compound (B) can be adjusted and reduced by methods such as catalyst selection at the time of synthesis of the compound and purification by molecular distillation after synthesis.
[0019]
There are no particular restrictions on the blending time of the glycerin monoester compound (B) and the phosphorus stabilizer (C) and the form at the time of blending in the polycarbonate resin (A), and it may be during or after the polymerization of the polycarbonate resin. Along with powder, pellet or bead-like polycarbonate resin, it can be mixed and melt-kneaded by mixing with an optional mixer such as a tumbler, ribbon blender, high-speed mixer or the like. Moreover, there is no restriction | limiting in the mixing | blending order of a glycerol monoester compound (B) and a phosphorus stabilizer (C), It can mix | blend and knead | mix in arbitrary orders.
[0020]
In addition, a known additive such as a phenol-based stabilizer [2,6-di-t-butyl-4-methylphenol, 2- (1-methylcyclohexyl) -4,6-dimethylphenol is used when mixing. 2,2-methylenebis- (4-ethyl-6-t-methylphenol), 4,4'-thiobis- (6-t-butyl-3-methylphenol), n-octadecyl 3- (3,5- Di-t-butyl-4-hydroxyphenyl) propionate etc.], UV absorber [pt-butylphenyl salicylate, 2,2'-dihydroxy-4-methoxybenzophenone, 2- (2'-hydroxy-4'- n-octoxyphenyl) benzotriazole, etc.], lubricant (paraffin wax, hydrogenated oil, n-butyl stearate, ketone wax, octyl alcohol, laur Alcohol, hydroxystearic acid triglyceride, etc.), colorant (eg, titanium oxide, carbon black, other dyes and pigments), filler (calcium carbonate, clay, silica, glass fiber, glass flake, glass sphere, carbon fiber, etc.), exhibition Adhesives (epoxidized soybean oil, liquid paraffin, etc.), fluidity improvers (triphenyl phosphate, etc.), decomposition inhibitors for polycarbonate resins (sulfur-containing compounds such as KHSO4, etc.), flame retardants (brominated polycarbonate oligomers, aromatics) Sulfur-containing metal salts, polytetrafluoroethylene, etc.) and other thermoplastic resins such as polymethyl methacrylate, polyamide, polyphenylene ether, polyacetal, polyvinyl chloride, polybutylene terephthalate, polyethylene terephthalate, styrene A series resin (ABS resin, styrene-acrylonitrile copolymer, polystyrene, etc.) and the like can be added as necessary.
[0021]
【Example】
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. “Parts” are based on weight.
[0022]
The compound shown below was mixed with 100 parts of polycarbonate resin “ PC” (viscosity average molecular weight 21,000) with a tumbler, and granulated to obtain pellets.
Glycerin monoester compound (B)
Glycerin monostearate: Sodium content 1ppm " GMS1"
Glycerin monostearate: sodium content 8ppm "GMS2"
Glycerin monostearate: sodium content of 13ppm "GMS3"
Glycerin monostearate: sodium content of 35ppm "GMS4"
Glycerin monostearate: sodium content of 45ppm "GMS5"
Phosphite stabilizer (C)
Tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylenephosphonite " PEPQ"
[0023]
Tables 1 to 3 show the blending amounts of the glycerin monoester compound and the phosphorus stabilizer and the release properties, residence heat stability, and low temperature impact resistance of the obtained polycarbonate resin composition. The releasability, residence heat stability and low temperature impact resistance were evaluated by the following methods.
[0024]
(Releasability)
Using an injection molding machine, FANUC · AUTOSHOT Model · 300D, a box-shaped molded product (draft angle: 2) having a width of 200x length of 250x depth of 40mm and a thickness of 2.5mm is molded and applied to the ejector at the time of mold release. The load was recorded as voltage, and the voltage value was converted into force (kg · f) to determine the release resistance.
[0025]
[Still heat stability]
The cylinder temperature is set at 340 ° C. using an injection molding machine (J100SAII) manufactured by Nippon Steel, and the sample is allowed to stay in the cylinder for 15 minutes. Thereafter, the retained sample was formed into a 40 × 70 × 3 mm plate in a cycle of 30 seconds, and the yellowness index (YI) and the degree of molecular weight reduction of the third shot plate having the largest thermochromic property were measured.
YI: Measured with a spectrophotometer CMS-35SP from Murakami Color Research Laboratory. A lower value is better.
Molecular weight: The molecular weight of the pellet and the molecular weight of the plate (third shot) after the thermal stability test (solution viscosity method (20 ° C.)) were measured, and the difference between the former and the latter was ΔMW. A lower value is better.
[0026]
(Low temperature impact resistance)
The notched Izod impact strength (thickness: 3.2 mm) at an arbitrary temperature is measured by the method of ASTM D-256 (n = 10), and the critical temperature at which the value transitions from a ductile state to brittleness is determined. The lower the temperature, the better.
[0027]
[Table 1]

[0028]
[Table 2]

[0029]
[Table 3]

[0030]
【The invention's effect】
In a polycarbonate resin composition obtained by blending a specific amount of a glycerin monoester compound, by setting the sodium content in the glycerin monoester compound to 20 ppm or less, a composition having excellent releasability and residence heat stability is obtained. be able to. This makes it possible to increase the size and thickness of the molded product in the polycarbonate resin composition, further increase the degree of freedom in designing the molded product, improve the surface smoothness, and improve the dimensional stability.

Claims (2)

In the composition formed by blending 0.01 to 0.8 parts by weight of the glycerol monoester compound (B) per 100 parts by weight of the polycarbonate resin (A), the sodium contained in the glycerol monoester compound (B) is 20 ppm or less. A polycarbonate resin composition having excellent residence heat stability. In a composition comprising 0.01 to 0.8 parts by weight of a glycerin monoester compound (B) and 0.005 to 0.5 parts by weight of a phosphorus stabilizer (C) per 100 parts by weight of a polycarbonate resin (A) A polycarbonate resin composition having excellent residence heat stability, wherein sodium contained in the glycerin monoester compound (B) is 20 ppm or less.