JP2014118415A - Polycarbonate resin composition and its molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polycarbonate resin composition suitable for molding processing at high temperatures and suitably used for housing materials or member subjects for vehicles requiring weather resistance.SOLUTION: There is provided a polycarbonate resin containing a polycarbonate resin (A) of 100 pts.wt., a mold releasing agent (B) of 0.005 to 0.3 pts.wt and an ultraviolet absorber (C) of 0.05 to 1 pts.wt. and the mold releasing agent (B) consists of a compound made by esterification of a compound containing a hydroxyl group and a compound having carboxyl group, and further a×b≤10 and b≥1.5 are satisfied when a is an acid value (mg/g) and b is a hydroxyl value (mg/g), and there is also provided its molded article.

Description

  The present invention relates to a polycarbonate resin composition excellent in thermal stability and weather resistance, in which a specific release agent is blended with a polycarbonate resin, and a molded article comprising the same.

  Polycarbonate resins are excellent in impact resistance, heat resistance, and transparency, and are widely used in various fields such as electric / electronic, optical, building materials, medical, food, and vehicles. For example, it is used for roofs of outdoor carports in building materials. However, polycarbonate resin has insufficient weather resistance. For example, in outdoor use or indoor use under fluorescent light irradiation, the use of the polycarbonate resin is reduced due to the discoloration of the product or deterioration of the mechanical strength due to deterioration due to ultraviolet irradiation. It was severely limited.

  In order to solve these problems, attempts have heretofore been made to blend a polycarbonate resin with a benzotriazole-based ultraviolet absorber, a hindered amine-based light stabilizer, or the like. For example, Patent Document 1 discloses that the composition of a benzotriazole ultraviolet absorber and a polycarbonate resin has good weather resistance. Recently, since more excellent weather resistance is required, for example, a polycarbonate resin having weather resistance in a wide ultraviolet region has been studied by using various ultraviolet absorbers alone or in combination of several kinds. However, in any case, there is a problem that the hue change is large when a thermal history such as retention at a high molding temperature is added. (Patent Document 2 and Patent Document 3).

  In order to solve such problems, Patent Document 4 proposes a method of using a specific release agent and a specific ultraviolet absorber and stabilizer in combination for the purpose of improving the releasability during molding. ing. However, the hue change due to the heat history during the molding process is still large, and there is a problem that the mold release property and weather resistance are not balanced.

JP-A-55-7292 JP 09-263694 A Japanese Patent No. 3298595 WO2005 / 116138

  The subject of this invention is providing the polycarbonate resin composition excellent in thermal stability and a weather resistance, and a molded article consisting thereof, maintaining balance with mold release property.

  As a result of diligent research to solve the above-mentioned problems, the present inventors surprisingly have remarkable thermal stability and weather resistance by blending a specific release agent with a polycarbonate resin containing an ultraviolet absorber. The inventors have found that it can be improved and have completed the present invention.

  That is, the present invention provides a polycarbonate resin composition comprising 100 parts by weight of a polycarbonate resin (A), 0.005 to 0.3 parts by weight of a release agent (B) and 0.05 to 1 parts by weight of an ultraviolet absorber (C). The release agent (B) comprises a compound obtained by esterifying a compound containing a hydroxyl group and a compound containing a carboxyl group, and further measured and calculated by a method according to JIS K2501-2003. A × b ≦ 10 and b ≧ 1 when the hydroxyl value is a (mg / g) and the hydroxyl value measured and calculated by a method according to JIS K 0070-1992 is b (mg / g). The polycarbonate resin composition characterized by satisfying 5 is provided.

  The polycarbonate resin composition of the present invention and a molded product comprising the same are excellent not only in releasability but also in thermal stability and weather resistance. Therefore, it is suitable for molding at high temperatures, and is suitably used for building materials and vehicle members that require weather resistance, and its practical utility value is extremely high.

  The polycarbonate resin (A) is a polymer obtained by a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted or a transesterification method in which a dihydroxydiaryl compound and a carbonic ester such as diphenyl carbonate are reacted. Among them, a polycarbonate resin produced from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) can be mentioned.

  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. These are used individually or in mixture of 2 or more types. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4'-dihydroxydiphenyl, and the like may be mixed and used.

  Furthermore, the above dihydroxyaryl compound and a trivalent or higher phenol compound as shown below may be used in combination. 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.

  The viscosity average molecular weight of the polycarbonate resin (A) is usually 10,000 to 100,000, preferably 15,000 to 35,000, and more preferably 17,000 to 28,000. In producing such a polycarbonate resin, a molecular weight regulator, a catalyst and the like can be used as necessary.

  The release agent (B) used in the present invention comprises a compound obtained by esterifying a compound containing a hydroxyl group and a compound containing a carboxyl group, and further measured by a method according to JIS K 2501-2003. A × b ≦ 10 when the calculated acid value is a (mg / g), the hydroxyl value measured and calculated by a method according to JIS K 0070-1992 is b (mg / g), and It is a requirement to satisfy b ≧ 1.5.

  The acid value of the release agent (B) is determined by a method according to JIS K 2501-2003. The acid value indicates the number of milligrams of potassium hydroxide required to neutralize the free fatty acid (acidic component) contained in 1 gram of the release agent, and the amount of unreacted esterification products and other acidic impurities It is shown as the sum of In order to reduce the unreacted esterification product, the acid value is preferably 1 mg / g or less, more preferably 0.5 mg / g or less.

  The hydroxyl value of the release agent (B) is determined by a method according to JIS K 0070-1992. The hydroxyl value indicates the number of milligrams of potassium hydroxide required for acetylating hydroxyl groups contained in 1 gram of fat and oil, and is indicated as the total amount of hydroxyl groups remaining including hydroxyl groups in the release agent. The hydroxyl value of the release agent (B) is 1.5 or more. When the hydroxyl value is less than 1.5, it is not preferable because the release property is poor.

  Examples of the compound containing a hydroxyl group and the compound containing a carboxyl group constituting the release agent (B) in the present invention are given below. Examples of the compound containing a hydroxyl group include glycerin, pentaerythritol, ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, triethylene glycol, hydrogen Bisphenol A, stearyl alcohol, bisphenol dihydroxypropyl ether, trimethylol ethane, trimellirol propane, dipentaerythritol and the like. In addition, the compound containing a carboxyl group is not particularly limited, and examples thereof include saturated fatty acids such as stearic acid. Of these, higher alcohol fatty acid esters and partial esters or full esters composed of pentaerythritol and aliphatic carboxylic acids are preferred, and these may be used alone or in combination of two or more.

  The compounding quantity of the mold release agent (B) in this invention is 0.005-0.3 weight part per 100 weight part of polycarbonate resin (A). A blending amount of less than 0.005 parts by weight is not preferable because sufficient releasability is not observed. Moreover, since it is inferior to thermal stability when it exceeds 0.3 weight part, it is unpreferable. A more preferable blending amount is in the range of 0.01 to 0.2 parts by weight.

  Although the ultraviolet absorber (C) used by this invention will not be specifically limited if it can provide a weather resistance, Various ultraviolet absorbers, such as a benzotriazole type, a triazine type, a benzophenone type, are mentioned.

Specific examples of the benzotriazole ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole, 2- (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chloro-2H-benzotriazole, 2- (3,5-di-tert-pentyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (2H-benzotriazol-2-yl) -4-methyl -6- (3,4,5,6-tetrahydrophthalimidylmethyl) phenol, 2- (2-hydroxy-4-octyloxyphenyl) -2H-benzotriazole, 2- (2-hydroxy-5-tert- Octylphenyl) -2H-benzotriazole, 2- [2′-hydroxy-3,5-di (1,1-dimethylbenzyl) fe Nil] -2H-benzotriazole, 2,2′-methylenebis [6- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol] and the like.
Specific examples of triazine-based UV absorbers include 2- [4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol. 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] phenol and the like. Specific examples of the benzophenone ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, and the like. Other examples include N- (2-ethylphenyl) -N ′-(2-ethoxyphenyl) oxalic acid diamide having an oxaanilide skeleton. These ultraviolet absorbers may be used alone or in combination of two or more.

  Among these, a benzotriazole type is preferable, and 2,2′-methylenebis [6- (2H-benzotriazol-2-yl) -4 is particularly preferable because it has less transpiration during thermoforming and hardly contaminates the mold. -(1,1,3,3-tetramethylbutyl) phenol] is preferably used. The ultraviolet absorber is readily available as a commercial product, and examples thereof include Tinuvin 329 manufactured by BASF.

  The compounding quantity of a ultraviolet absorber (C) is 0.05-1 weight part per 100 weight part of polycarbonate resin (A). If the blending amount is less than 0.05 parts by weight, the effect of improving weather resistance is not recognized, which is not preferable. Moreover, when it exceeds 1 weight part, a metal mold | die and a roll will be easily contaminated with the transpiration | evaporation at the time of a thermoforming process, and it is not preferable. A more preferable blending amount is in the range of 0.15 to 0.5 parts by weight.

  In the polycarbonate resin composition of the present invention, various known additives, polymers and the like other than the above can be added as desired within the range not impairing the effects of the present invention. For example, antioxidant, fluorescent brightener, colorant [eg, titanium oxide, carbon black, dye], filler [calcium carbonate, clay, silica, glass fiber, glass sphere, glass flake, carbon fiber, talc, mica, Various whiskers, etc.], fluidity improver, flame retardant [bromine, phosphorus, silicone, etc.], spreading agent [epoxidized soybean oil, liquid paraffin, etc.], and other thermoplastic resins and various impact resistances An improver (for example, rubber reinforced resin obtained by graft polymerization of a compound such as methacrylic acid ester, styrene, or acrylonitrile on rubber such as polybutadiene, polyacrylic acid ester or ethylene / propylene rubber) is required. Can be added accordingly.

  The blending method of the constituent components (A), (B), and (C) of the present invention is not particularly limited. For example, after batch mixing with a tumbler, ribbon blender, high-speed mixer, etc., the mixture is mixed with a normal uniaxial or biaxial mixture. A method of melt-kneading and pelletizing using a shaft extruder, or a method of measuring each component separately, putting them into a extruder from a plurality of feeders, and melt-mixing them, and (A) to (B) And / or (A), (C) is blended at a high concentration, and once melt-mixed and pelletized to obtain a master batch, the master batch and (A) can be mixed at a desired ratio. . Then, when these components are melt-mixed, arbitrary conditions such as a position to be introduced into the extruder, an extrusion temperature, a screw rotation speed, a supply amount, and the like can be selected and pelletized. Further, the master batch and (A) can be mixed by dry mixing at a desired ratio and then directly fed into a molding machine to form a molded product. The method for molding the polycarbonate resin composition having excellent thermal stability, releasability and weather resistance of the present invention is not particularly limited, and a known injection molding method, extrusion molding method, injection / compression molding method or the like is used. be able to.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, “%” and “parts” in the examples are based on weight standards.

The raw materials used are as follows.
Polycarbonate resin:
Polycarbonate resin synthesized from bisphenol A and phosgene (Caliber 200-13, manufactured by Sumika Stylon Polycarbonate)
Viscosity average molecular weight: 21500, hereinafter abbreviated as “PC”)

Release agent:
Nissan Electol WEP-5 manufactured by NOF Corporation
Ester of pentaerythritol and aliphatic carboxylic acid Acid value a: 0, hydroxyl value b: 2.5, a × b = 0 (hereinafter abbreviated as “MR1”)
Rikenmar SL-900A manufactured by Riken Vitamin
Higher alcohol fatty acid ester acid value a: 1.9, hydroxyl value b: 4, a × b = 7.6 (hereinafter abbreviated as “MR2”)
NISSAN ELECTOL WEP-4 manufactured by NOF Corporation
Ester of pentaerythritol and aliphatic carboxylic acid Acid value a: 0.1, hydroxyl value b: 0.8, a × b = 0.1 (hereinafter abbreviated as “MR3”)
Rikenmar S-100A manufactured by Riken Vitamin
Glycerin fatty acid ester acid value a: 0.3, hydroxyl value b: 313, a × b = 94 (hereinafter abbreviated as “MR4”)

UV absorber:
Tinuvin 329 manufactured by BASF
Benzotriazole UV absorber (hereinafter abbreviated as “UVA”)
Colorant:
LANXESS Macrolex Violet B
Anthraquinone dyes (hereinafter referred to as “colorants”)

  Each of the above-mentioned various raw materials was put into a tumbler at the blending ratios shown in Table 1 and Table 2, and after dry mixing for 10 minutes, a twin-screw extruder (TEX30α manufactured by Nippon Steel Works, shaft diameter = 30 mmφ, L / D = 41), kneading was performed at a melting temperature of 280 ° C., and pellets of various polycarbonate resin compositions for evaluation were obtained.

Hereinafter, various evaluation items and measurement methods in the present invention will be described.
(Stability thermal stability)
Each of the obtained pellets was dried in advance at 120 ° C. for 4 hours, and then the thermal stability of the residence was maintained using an injection molding machine (J100E2P manufactured by Nippon Steel) under a cylinder set temperature of 360 ° C. Evaluated. As the mold, a plate mold having a length of 50 mm, a width of 50 mm, and a thickness of 2 mm was used. L *, a, and b values were obtained using a high-speed color analyzer CMS-35SP manufactured by Murakami Color Research Laboratory Co., Ltd., using the first shot plate before dwelling and the second shot plate after dwelling for 15 minutes. ΔE = [(ΔL *) ² + (Δa) ² + (Δb) ² ] The color difference ΔE was calculated from the L *, a, and b values before and after irradiation, using the equation of ^1/2 . As a criterion for evaluation, a case where ΔE was less than 2 was judged as good (◯), and a case where ΔE was 2 or more was judged as bad (x).

(Releasability)
Each of the obtained pellets was dried in advance at 120 ° C. for 4 hours, and then using an injection molding machine (J100E2P manufactured by Nippon Steel), cylinder set temperature 280 ° C., mold temperature 50 ° C., cooling time The releasability was evaluated under the condition of 20 seconds. Using a cup-type mold release resistance mold (molded product shape: diameter 70 mm, height 20 mm, thickness 4 mm), the protruding load applied to the protruding pin when molding a cup-shaped molded product is measured. The mold release resistance value (N) was determined. As a criterion for evaluation, a case where the release resistance value was less than 3000 (N) was judged as good (◯), and a case where it was 3000 (N) or more was judged as defective (x).

(Weatherability)
Each of the obtained pellets was dried in advance at 120 ° C. for 4 hours, and then a flat test piece (vertical length) was used at a cylinder set temperature of 300 ° C. using an injection molding machine (J100E2P manufactured by Nippon Steel). 50 mm, width 50 mm, thickness 2 mm). Thereafter, the prepared plate was irradiated with a super xenon weather meter SX75 manufactured by Suga Test Instruments Co., Ltd. for 750 hours under the conditions of an irradiation intensity of 150 W / m 2, a black panel temperature of 63 ° C., and a relative humidity of 50%. Using the plate after irradiation, the YI value was determined by a high-speed color analyzer CMS-35SP manufactured by Murakami Color Research Laboratory. As a criterion for evaluation, a case where ΔYI was less than 12 was judged as good (◯), and a case where it was 12 or more was judged as bad (x).

(Comprehensive judgment)
In the evaluation of the residence heat stability, the mold release property and the weather resistance, all that passed were judged as good (◯), and those that were not good were judged as bad (×).

  As shown in Table 1, when the configuration of the present invention was satisfied (Examples 1 to 6), all the evaluation items had sufficient performance.

On the other hand, as shown in Table 2, when the configuration of the present invention was not satisfied (Comparative Examples 1 to 6), each case had some defects.
Comparative Example 1 was a case where the compounding amount of the release agent was less than the specified amount, and although the thermal stability and weather resistance were good, the release property was inferior.
Comparative Example 2 was a case where the compounding amount of the release agent was larger than the specified amount, and although the release property and weather resistance were good, the thermal stability was inferior.
Comparative Example 3 was a case where a release agent having a hydroxyl value b of less than 1.5 was used, and although the thermal stability and weather resistance were good, the release properties were inferior.
In Comparative Example 4, a release agent having an acid value a × hydroxyl value b of 10 or more was used, and although the release property was good, the thermal stability and the weather resistance were inferior.
Comparative Example 5 was a case where the blending amount of the ultraviolet absorber was less than the specified amount, and although the thermal stability and release properties were good, the weather resistance was inferior.
Comparative Example 8 was a case where the blending amount of the ultraviolet absorber was larger than the specified amount, and although the release property and weather resistance were good, the thermal stability was inferior.

Claims (3)

  A polycarbonate resin composition comprising 100 parts by weight of a polycarbonate resin (A), 0.005 to 0.3 parts by weight of a release agent (B) and 0.05 to 1 part by weight of an ultraviolet absorber (C), The mold agent (B) is composed of a compound obtained by esterifying a compound containing a hydroxyl group and a compound containing a carboxyl group, and the acid value measured and calculated by a method according to JIS K2501-2003 is a (mg / mg). g), when a hydroxyl value measured and calculated by a method according to JIS K 0070-1992 is b (mg / g), a × b ≦ 10 and b ≧ 1.5. A polycarbonate resin composition.   The polycarbonate resin composition according to claim 1, wherein the release agent (B) is selected from a higher alcohol fatty acid ester and a partial ester or a full ester composed of pentaerythritol and an aliphatic carboxylic acid.   A molded article formed by molding the polycarbonate resin composition according to claim 1 or 2.