JPH0748506A - Weather-resistant resin composition - Google Patents

Abstract

PURPOSE:To provide the composition which is excellent in especially heat stability during molding and can provide a molding excelling in appearance and impact resistance and undergoing very little surface fading or discoloration at the time of long exposure to for example sunlight in outdoor use, sunlight passed through a window glass in indoor use or light from a fluorescent lamp in indoor use. CONSTITUTION:The composition comprises 100 pts.wt. total of 10-90 pts.wt. polyphenylene ether and 90-10 pts.wt. styrene polymer, 0.05-5 pts.wt. UV absorber, 0.05-5 pts.wt. light stabilizer, and 0.05-5 pts.wt. tetrakis(2,4-di-tert- butylphenyl)-4,4'-biphenylene phosphite.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The resin composition of the present invention can be applied to the surface of a molded article when exposed to sunlight for outdoor use, sunlight through a window for indoor use, fluorescent light in a room, etc. for a long time. It is a weather-resistant resin composition that has very little discoloration and fading and is particularly excellent in impact resistance and thermal stability during molding, and can be used in a wide range of fields such as electric and electronic parts, automobile parts, machine parts, and sundries. is there.

[0002]

2. Description of the Related Art Conventionally, a composition composed of polyphenylene ether (hereinafter abbreviated as PPE) and a styrene polymer (hereinafter abbreviated as PS) has been used for electrical properties, mechanical properties, heat resistance, hot water resistance, dimensional accuracy, and moldability. It is used in the fields of electric / electronic parts, automobile parts, machine parts, sundries, etc. However, PPE and PS
Molded product from a composition containing as a main component, sunlight when used outdoors for a long time, sunlight through a window when used indoors,
When exposed to indoor fluorescent lamps, etc., it causes a problem that the discoloration and fading of the surface of the molded product is extremely large, and its use is very limited. Therefore, it has been strongly desired to prevent discoloration and fading of the surface of a molded article from a composition containing PPE and PS as main components when exposed to such various kinds of light.

JP-A-60-168756 discloses that orthohydroxy-substituted alkoxybenzophenones and tetraalkyldipipedinyl aliphatic diesters are PP.
It is disclosed that addition to E can prevent the occurrence of discoloration and fading on the surface of the molded product. However, compounds such as orthohydroxy-substituted alkoxybenzophenones and tetraalkyldipipedinyl aliphatic diesters and P
When added to PE or PS, heat deterioration occurs during melt-kneading or molding, black stripes are generated on the surface of the molded product, and the commercial value is significantly reduced. Japanese Patent Application Laid-Open No. 61-62545 discloses PP.
A method of adding zinc oxide and a nickel-based complex to E has been proposed. Even with this method, discoloration and fading can be prevented to some extent, but when it is exposed to various kinds of light for a long time, the discoloration and fading becomes large, which is not yet satisfactory. Special table Sho 57-5
No. 02062 proposes that the impact resistance is improved by adding titanium oxide having a particle size of about 0.1 to 0.2 μm and an impact modifier to PPE. Even with this method, the impact resistance is certainly improved to some extent, but the improvement in the light resistance is very low.

[0004]

SUMMARY OF THE INVENTION The problems to be solved by the present invention are as follows:
When exposed to sunlight through windows during indoor use, indoor fluorescent lights, etc., the discoloration and fading of the surface of the molded product is extremely small, and the molded product's appearance, mechanical properties, and heat resistance are excellent. It is an object of the present invention to provide a weather-resistant resin composition having good thermal stability, excellent impact resistance, and discoloration of the entire surface of a molded product or partial black stripes.

[0005]

In order to solve the above problems, the present inventors have added various substances to PPE and PS at various ratios and conducted repeated studies. As a result, a composition comprising PPE and PS is added to a specific UV absorber and / or light stabilizer, and a tetrakis- (2,4-di-t-butylphenyl) 4,4'-biphenylene phosphite as a heat stabilizer. Was blended and melt-kneaded to find a resin composition having excellent thermal stability, impact resistance and weather resistance during molding, and the present invention was completed.

The (A) PPE used in the present invention can be produced, for example, according to the method described in JP-A-63-286464. In particular, poly (2,6-dimethyl-1,
4-phenylene) ether, 2,6-dimethyl-1,4
-Phenol / 2,3,6-trimethyl-1,4-phenol copolymer and a graft copolymer obtained by graft-polymerizing styrene to the former two are used in the present invention.
Preferred as PE. The intrinsic viscosity of PPE suitable for the present invention is measured with a chloroform solution at 25 ° C. and is 0.35 to 0.6.
It is preferably in the range of 0 dl / g. Intrinsic viscosity is 0.
When it is higher than 60 dl / g, the melt viscosity of the composition becomes high,
The bar flow value decreases, making it especially difficult to mold large-sized thin-walled molded products. On the other hand, when the intrinsic viscosity is lower than 0.35 dl / g, the mechanical strength is largely reduced and the value as a practical molded product is impaired, so that it cannot be used in the resin composition of the present invention.

The styrene-based polymer (B) used in the present invention is a resin containing 25% by weight or more of styrene, and is, for example, PS, HIPS, MS, MBS, AS,
AAS, AES, AMBS, styrene-maleic acid copolymer resin (for example, manufactured by Arco Chemical Co., USA, trade name Dailark), SBR, styrene / butadiene block copolymer, hydrogenated styrene / butadiene block copolymer, hydrogenation SEBS elastomer (for example, Shell Chemical Co., Ltd., trade name Kraton G), core / shell type elastomer (for example, Takeda Yakuhin Co., Ltd. trade name, Star core made of rubber and shell layer made of hard resin) Floyd), MBS elastomer, Kureha BTA elastomer, diblock or triblock copolymer composed of polystyrene phase and hydrogenated polyisoprene phase (for example, Kuraray Co., Ltd., trade name Septon),
One or more polymers selected from these are used.

As the (C) ultraviolet absorber used in the present invention, a hydroxybenzotriazole compound is preferably used. The hydroxybenzotriazole compound is a compound having a hydroxy group and a triazole ring in the molecule, and specifically, 2- (2′-hydroxy-3).
′ -Methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-5′-methylphenyl)
-5-fluorobenzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5-bromobenzotriazole, 2 -(2 '
-Hydroxy-3'-ethylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-ethylphenyl) -5-chlorobenzotriazole, 2-
(2'-hydroxy-3 ', 5'-dimethylphenyl)
-5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-diethylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5
′ -Dipropylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-
Butylphenyl) -5-chlorobenzotriazole, 2
-(2'-hydroxy-3'-methyl-5'-ethylphenyl) -5-chlorobenzotriazole, 2- (2 '
-Hydroxy-3'-ethyl-5'-methylphenyl)
-5-chlorobenzotriazole, 2- (2'-hydroxy-3'-methyl-5'-propylphenyl) -5-
Chlorobenzotriazole, 2- (2'-hydroxy-
3'-propyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-
Methyl-5'-t-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-t-
Butyl-5'-methylphenyl) -5-chlorobenzotriazole and the like.

As the (D) light stabilizer used in the present invention, a hindered amine light stabilizer is preferably used.
Specific examples of the hindered amine light stabilizer include bis (1,2,2,6,6-pentamethyl-4-piperidyl) oxalate and bis (1,2,2,6,6-pentamethyl-4-piperidyl). ) Malonate, bis (1,2,
2,6,6-Pentamethyl-4-piperidyl) adipate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-) Examples thereof include piperidyl) terephthalate and bis (1-ethyl-2,2,6,6-tetramethyl-4-piperidyl) sebacate.

Next, the compounding ratio of the resin composition of the present invention is
(A) PPE 10 to 90 parts by weight, (B) PS 90 to 10
Parts by weight, and based on 100 parts by weight of the total amount of both, (C) an ultraviolet absorber of 0.05 to 5 parts by weight, (D) a light stabilizer of 0.05
˜5 parts by weight, and (E) tetrakis- (2,4-di-t-butylphenyl) 4,4′-biphenylene phosphite 0.05 to 5 parts by weight. When PPE is less than 10 parts by weight, heat resistance and mechanical strength are low, and when it exceeds 90 parts by weight, melt viscosity becomes high and molding becomes difficult. On the other hand, if PS is less than 10 parts by weight, the effect of improving melt viscosity and impact resistance will be poor, and if it exceeds 90 parts by weight, the mechanical properties and thermal properties inherent to PPE will be impaired.

If the compounding ratio of the ultraviolet absorber is less than 0.05 parts by weight, the effect of improving weather resistance is small, and if it exceeds 5 parts by weight, mechanical properties such as load deflection temperature and impact resistance are largely deteriorated. Absent. The compounding ratio of the preferable ultraviolet absorber is 0.1 to 3 parts by weight, and more preferably 0.5 to 2 parts by weight. If the compounding ratio of the light stabilizer is less than 0.05 part by weight, the effect of improving the weather resistance is small, and if it exceeds 5 parts by weight, mechanical properties such as load deflection temperature and impact resistance are largely deteriorated, which is not preferable. The compounding ratio of the light stabilizer is preferably 0.1 to 3 parts by weight, more preferably 0.5 to 2 parts by weight. Tetrakis- (2,4-di-t-butylphenyl) 4,4 '
-If the compounding ratio of biphenylene phosphite is less than 0.05 parts by weight, the effect of improving the thermal stability is small and the impact resistance is lowered, and if it exceeds 5 parts by weight, the elongation at break and the deflection temperature under load are greatly lowered. Preferred tetrakis- (2,4-
The compounding ratio of di-t-butylphenyl) 4,4′-biphenylene phosphite is 0.1 to 3 parts by weight, and more preferably 0.3 to 1 part by weight.

Other thermoplastic resins such as PC, PE, PP, maleic acid modified PP, POM, PMMA, various aliphatic nylons and aromatic nylons, polyphenylene sulfides, polyethers, etc. are used within the range not impairing the object of the present invention. Compatibilizers such as ether ketone, polysulfone, and organic acid anhydride may be added in some cases. In order to improve the mechanical strength, rigidity and dimensional stability of the resin composition of the present invention, glass fiber, glass beads, glass flakes, glass fiber cloth, glass fiber mat, graphite, carbon fiber, carbon fiber cloth, carbon fiber mat, Metal fibers and flakes made from carbon black, carbon flakes, aluminum, stainless steel, brass and copper, metal powders, organic fibers, acicular titanium potassium potassium, mica, talc, clay, (acicular) titanium oxide, wollastonite One or more reinforcing agents selected from calcium carbonate and calcium carbonate may be added. In order to increase the rigidity and strength and further improve the appearance and smoothness of the molded product, it is preferable to make the diameter of the fiber thin. As the glass fiber having a small fiber diameter, E-manufactured by Nippon Inorganic Co., Ltd. described in Japanese Patent Application No. 02-177585.
FMW-800 (average fiber diameter 0.8 μm) and E-FMW
-1700 (average fiber diameter 0.6 μm) can be exemplified.

The surface of the reinforcing agent is a known surface treatment agent such as vinylalkylsilane, methacryloalkylsilane, epoxyalkylsilane, aminoalkylsilane,
The surface treatment may be performed with a titanate coupling agent such as mercaptoalkylsilane, chloroalkylsilane, isopropyltriisostearoyl titanate, or a zircoaluminate coupling agent. Further, as a sizing agent for fibers, a known sizing agent such as epoxy type, urethane type, polyester type, styrene type sizing agent may be used for sizing.

In the resin composition of the present invention, if necessary,
As a flame retardant, triphenyl phosphate, tricresyl phosphate, a polycondensate thereof, or a known phosphorus compound such as red phosphorus can be added. Further, a halogen compound such as decabromodiphenyl ether, brominated polystyrene, low molecular weight brominated polycarbonate, or brominated epoxy compound can be added as a flame retardant. Flame retardant aids such as antimony trioxide, antimony tetraoxide, zirconium oxide can also be used in combination with the halogen compound.

In the resin composition of the present invention, if necessary,
Known heat and antioxidants such as phenol type, thioether type, zinc oxide and zinc sulfide can be used.
Further, if necessary, an antistatic agent, a plasticizer, a lubricant, a release agent, a dye, a pigment and the like can be added. The resin composition of the present invention can be produced by the equipment and method generally used for producing a thermoplastic resin composition. For example, the components constituting the resin composition of the present invention may be collectively melt-kneaded using a uniaxial or biaxial extruder and extruded to produce molding pellets.

Next, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these. The molding method and test method of the test piece in the examples and comparative examples are as follows.

(1) Raw materials used PPE was manufactured by Mitsubishi Gas Chemical Co., Inc. and had an intrinsic viscosity in chloroform at 25 ° C. of 0.45 dl / g. High impact polystyrene HI-S-3 (abbreviated as HIPS) manufactured by Denki Kagaku Co., Ltd. was used as the styrene-based polymer, and triphenyl phosphate (abbreviated as TPP) was used as the flame retardant. As a hydroxybenzotriazole-based compound, 2- (2′-hydroxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzotriazole (Sumitomo Chemical Co., Ltd., trade name Sumisorb 300, Sumisorb) is abbreviated. ) Or (2'-hydroxy-3 ', 5
′ -Di-t-butylphenyl) -5-chlorobenzotriazole (manufactured by Asahi Denka Co., Ltd., trade names LA-34, LA-
(Abbreviated as 34) was used. The hindered amine light stabilizer includes bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate (manufactured by Sankyo Co., Ltd., trade name Sanol LS-765, LS-765) or tetrakis (1). , 2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate (manufactured by Asahi Denka Co., Ltd., trade name LA-52, abbreviated as LA-52) was used. . As a heat stabilizer, tetrakis- (2,
4-di-t-butylphenyl) 4,4'-biphenylene phosphite (abbreviated as P-EPQ) was used. For comparison, diphenylmono (2-ethylhexyl) phosphite (abbreviated as PEP) and bis (nonylphenyl) pentaerythritol diphosphite (abbreviated as NPD hereinafter) were used as heat stabilizers.

(2) Mixing method of composition After mixing each sample of (1) in the ratios shown in Tables 1 and 2, a twin screw extruder having a screw diameter of 30 mm was used to set a cylinder temperature of 240 to 300 ° C. and a screw rotation speed. 30 to 10
After melt-kneading at 0 rpm, it was pelletized and used for molding.

(3) Molding condition of test piece After drying the pellets produced under (2) at 100 ° C. for 5 hours,
Sumitomo Heavy Industries, Ltd. SG125 type injection molding machine, mold temperature 70 ℃, cylinder set temperature 250 ~ 290 ℃, injection pressure 98 MPa, ASTM-D638 regulation type 1
3.2mm thick tensile test piece of 63.5 × 12.7 ×
A 3.2 mm Izod impact test piece was molded for 40 shots (160 pieces each), the first 10 shots were discarded, and the last 10 shots were used for the tests (5), (6) and (7). The appearance of the Izod impact strength of the 5th shot and that of the 40th shot are compared (displayed with untreated appearance), A shows no change, B shows almost no change,
A slight change was designated as C, and a slight change was designated as D.

(4) Retention test After the test of (3) was completed, molding was interrupted for 30 minutes while keeping the cylinder temperature and the mold temperature as they were, and then two shots (8 pieces) were molded, and the appearance of the molded product (retention) was retained. Appearance and abbreviation) and Izod impact strength (abbreviated as retention impact) were measured. With respect to the appearance of the molded product after the retention, the one having almost no change in color before and after the retention was A, the slight change was B, the slight change was C, and the considerable change was D.

(5) Tensile breaking elongation According to ASTM-D638, five tests were carried out at a pulling speed of 5 mm / min and a test temperature of 23 ° C., and an average breaking elongation (unit:%) of five was determined.

(6) Izod impact strength (unit: J /
m) According to ASTM-D256, a notch of 0.25R is cut into a test piece having a test piece thickness of 3.2 mm by cutting,
Five pieces were measured at 23 ° C., and the average value of the five pieces was shown.

(7) Light resistance test A 63.5 × 12.7 × 3.2 mm Izod impact test piece was exposed to a 6.5 KW xenon arc fade meter (CI-65 type manufactured by Atlas, USA). Then, Pyrex glass was attached to the inner part of the filter used and clear glass was attached to the outer part, and the treatment was carried out under conditions of a black panel temperature of 63 ° C. and no rain spray.
The test piece after 300 hours of treatment is manufactured by Nippon Denshoku Industries Co., Ltd. Σ
The yellowing degree ΔYI was measured with a -80 type color difference meter, and the weather resistance was compared, and the results are shown in Tables 1 and 2.

[0024]

EXAMPLES Examples are shown in Table 1 and comparative examples are shown in Table 2. In addition,
The compounding ratio of each component which comprises the resin composition of Table 1-Table 2 is shown by weight part.

[0025]

EFFECT OF THE INVENTION The resin composition of the present invention is used for a long period of time when it is used outdoors for outdoor use, when it is used indoors for sunlight through a window,
When exposed to indoor fluorescent lamps, the surface of the molded product has very little discoloration and discoloration, and in particular, it has good impact resistance and heat resistance, and is a weather-resistant resin composition with excellent thermal stability during injection molding. In addition to injection molding, extrusion molding and blow molding are also possible. Electric / electronic parts, automobile parts, machine parts,
It can also be used for parts that are exposed to various lights in the field of sundries.

[0026]

[Table 1]Example 1 2 3 4 5 6 7 8 (Compounding ratio) PPE 33 33 33 33 33 60 60 60 60 60 HIPS 60 60 60 60 30 30 30 30 30 TPP 7 7 7 7 10 10 10 10 Sumisorb 1 1 1 1 LA-341 1 1 1 1 LS-765 1 LA-52 1 1 1 1 1 P-EPQ 0.3 0.5 0.7 0.7 1.0 0.3 0.5 0.7 1 (Physical properties) Untreated appearance A A A A A A A A A Retention appearance B B B B B B B B B Break elongation 33 28 31 35 32 36 36 34 29 Untreated impact 220 225 230 245 240 250 255 260 Residence impact 210 210 205 220 230 210 235 235 240 ΔYI 26 29 27 27 29 31 31 30 29

[0027]

[Table 2]Comparative Example 1 2 3 4 5 6 7 8 (Compounding ratio) PPE 33 33 33 33 33 60 60 60 60 60 HIPS 60 60 60 60 30 30 30 30 30 TPP 7 7 7 7 10 10 10 10 Sumisorb 1 1 1 1 LA-341 1 1 1 1 LS-765 1 LA-52 1 1 1 1 1 PEP 0.3 1 0.3 0.3NPD 0.3 1 1 1 1 (Physical properties) Untreated appearance A A A A A A A A A Retention appearance D D D C D C C D D Elongation at break 16 18 11 18 16 21 21 18 19 Untreated impact 110 125 125 120 135 130 120 135 135 130 Retention impact 35 65 45 45 60 40 55 35 40 ΔYI 39 38 36 36 39 37 41 43 42

Claims (3)

[Claims] 1. A polyphenylene ether 10-90.
Parts by weight, (B) styrene-based polymer 90 to 10 parts by weight,
(C) UV absorber 0.05 to 5 parts by weight, (D) Light stabilizer 0.05 to 5 parts by weight, and (E) Tetrakis- (2,4-di-) based on 100 parts by weight of the total amount of both. t-butylphenyl) 4,4'-biphenylene phosphite 0.05
~ 5 parts by weight of a resin composition. 2. The resin composition according to claim 1, wherein the ultraviolet absorber (C) is a hydroxybenzotriazole type ultraviolet absorber. 3. The resin composition according to claim 1, wherein (D) the light stabilizer is a hindered amine light stabilizer.