JPH0665465A - Propylene resin composition - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a resin composition having excellent rigidity, impact resistance, heat resistance, weather resistance and paintability. [PROBLEMS] A polypropylene resin composition characterized by containing a specific additive combination with respect to a specific resin combination mainly composed of a propylene-ethylene block copolymer.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a propylene resin composition. More specifically, it relates to a propylene resin composition having excellent rigidity and impact resistance, as well as excellent heat resistance, weather resistance and paintability.

[0002]

2. Description of the Related Art Polypropylene has excellent mechanical properties such as rigidity, impact resistance, dimensional stability and heat resistance, and is used in a wide range of applications such as film applications and injection molding applications. High rigidity and low temperature impact strength are required for automobile parts applications, which are in great demand in injection molding applications, and more recently, paintability has become one of the important physical properties required. As a material satisfying such physical properties and paintability,
Japanese Patent Publication No. 64-2536 discloses a method for obtaining a resin composition for bumpers in which polypropylene is mixed with rubber and an inorganic filler, but there is a problem of yellowing of the coating film after coating, and the coating property is sufficient. , Not satisfactory.

On the other hand, polypropylene has the drawback that it is easily deteriorated by the action of ultraviolet rays, as seen when it is used outdoors. Therefore, generally, in order to suppress deterioration due to ultraviolet rays, for example, salicylate-based compounds, benzophenone-based compounds, benzotriazole-based compounds, nickel chelate-based compounds, hindered amine-based compounds, etc. are added to polyolefins alone or in combination. Is known (Japanese Patent Laid-Open No. 58-113236).
JP-A-59-219353).

However, there is a drawback in that the thermal oxidative stability and the light stability are remarkably lowered by the addition of the inorganic filler as compared with the case where the filler is not incorporated, and improvement thereof has been earnestly desired. In this regard, various methods have been proposed in order to improve the thermal oxidative deterioration and the photo-deterioration from the conventional method (for example, Japanese Patent Laid-Open No. Sho 5).
2-49254, JP-A-52-80345, JP-A-53-79938, and JP-A-56-90.
No. 844, JP-A-56-118437 and JP-A-56-141339), but these known methods are not always sufficient.

As a cause of the deterioration of the thermal oxidative stability and the light stability of the system containing the inorganic filler, the thermal oxidative stabilizer and the light stabilizer added to prevent the thermal oxidative deterioration and the optical deterioration are inorganic fillers. Since it is inactivated by the agent, its effect is considered to be insufficient.

Therefore, in order to prevent the above-mentioned thermal oxidative deterioration and photo-deterioration, it has been necessary to blend more thermal oxidative stabilizers and optical stabilizers than in the past. However, in order to prevent thermal oxidative deterioration and photodegradation as described above, if a large amount of various stabilizers is added, the stabilizers bleed on the surface, resulting in a decrease in coating film adhesion strength and a yellowing of the coating film.

Japanese Unexamined Patent Publication (Kokai) No. 2-49042 discloses a method for improving light stability without increasing the amount of stabilizer added. According to this method, paintability and light resistance are improved. However, satisfactory results cannot be obtained with respect to thermal oxidation stability.

[0008]

The object of the present invention is to improve the thermal oxidative stability and the light stability, which are the drawbacks of the conventional polypropylene compositions containing an inorganic filler, and to have an excellent coating property. A polypropylene resin composition is provided.

[0009]

The present inventors have various methods for improving thermal oxidation stability and light stability and satisfying paintability without impairing the required rigidity and impact strength. As a result of investigation, they found that the intended purpose was achieved in a polypropylene resin composition having a certain composition, and completed the present invention.

That is, according to the present invention, (I) the melt index is 15 to 30 (g / 10 minutes) and the ethylene content is 5
˜15% by weight, the ethylene content of the propylene / ethylene copolymerization part is 30-60% by weight, and the copolymerization part 135 ° C.
50-70 parts by weight of propylene-ethylene block copolymer having an intrinsic viscosity of 4-10 (dl / g) in a tetralin solution, (II) ethylene content of 40-80% by weight, Mooney viscosity ML _{1 + 4} 100 ° C. Of 15 to 45, and 25 to 35 parts by weight of ethylene-propylene copolymer rubber having an intrinsic viscosity of 1.2 to 2.0 (dl / g) in a 70 ° C. xylene solution, and (III) an average particle diameter of 0. Talc 5-2 which is .5-10 μ
For 100 parts by weight of a resin composition consisting of 0 parts by weight, (I
V) Tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate 0.01 to 0.5 parts by weight,
(V) The following general formula

[Chemical 4] (In the formula, R ₁ is a methyl group, a tertiary butyl group, or a tertiary group.
Indicates an amyl group. R ₂ represents a hydrogen atom, a methyl group, a tertiary butyl group, a tertiary amyl group, a phenyl group or a cyclohexyl group. R ₃ represents a hydrogen atom, a methyl group, or a tert-butyl group. R ₄ is hydrogen atom, methyl group or tertiary
A butyl group is shown. However, R ₂ , R ₃ and R ₄ do not all represent hydrogen atoms at the same time. ) Pentaerythritol diphosphite compound 0.03-0.
3 parts by weight, (VI) phenyl benzoate compound 0.0
1 to 0.5 parts by weight, (VII) 0.01 to 0.5 parts by weight of a heterocyclic hindered amine compound, and (VII
I) The following general formula

Embedded image R ₇ —CO—NH— (CH ₂ ) _n —HN—CO—R ₇ (In the formula, R ₇ represents an alkyl group or an alkenyl group having 5 to 21 carbon atoms. N is 1 to 6) 0.01 to 0.5 part by weight of a compound represented by the formula

[Chemical 6] (In the formula, R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group or an aryl group;
₅ and R ₆ may be the same or different. ) A propylene resin composition comprising a compound represented by the formula (1) in an amount of 1/3 or less of the heterocyclic hindered amine compound (VII).

The propylene-ethylene block copolymer (I) used in the present invention is prepared by first polymerizing propylene with a Ziegler-Natta catalyst to prepare a polypropylene part, and then copolymerizing a mixture of propylene and ethylene. can get. The block copolymer is
Melt index 15 to 30 (g / 10 minutes), preferably 15 to 25 (g / 10 minutes), ethylene content 5
Is about 15 to 15% by weight, the ethylene content of the propylene / ethylene copolymerization part is 30 to 60% by weight, and the ethylene content of the copolymerization part is 135%.
C. tetralin solution has an intrinsic viscosity of 4-10 (dl / g),
Preferably, it is 4.5 to 8 (dl / g). If the melt index is less than 15 (g / 10 minutes), a bumper molded article with excellent appearance (flow mark, gloss) cannot be obtained, and if it is more than 30 (g / 10 minutes), physical properties, particularly impact strength The decrease is significant. Further, when the ethylene content of the propylene / ethylene copolymerized portion is out of the above range, the impact strength is lowered, when the intrinsic viscosity of the copolymerized portion is less than 4, the impact strength is lowered, and when it is more than 10, the fluidity and the appearance are poor. Becomes

The ethylene content as referred to herein is obtained from infrared absorption spectrum, and the intrinsic viscosity [η] _{EP of} a 135 ° C. tetralin solution of the propylene-ethylene copolymerization part is
Means the viscosity calculated by the following formula.

[0013]

[Formula 1]

[Η] _P : Intrinsic viscosity of polypropylene polymerized part [η] _T : Intrinsic viscosity of final polypropylene-ethylene block copolymer X: Polymerization ratio of polypropylene and ethylene copolymerized part in the block copolymer (here , The polymerization ratio was determined by measuring the heat of crystal fusion of the polypropylene part and the final block copolymer.)

The ethylene-propylene copolymer rubber (II) used in the present invention has an ethylene content of 40 to 80% by weight and a Mooney viscosity ML _{1 + 4} 100 ° C. of 15 to 45, preferably 15 to 35, and 70. C. xylene solution has an intrinsic viscosity of 1.2 to 2.0, preferably 1.2 to 1.7 (dl /
g). When the ethylene content is out of the above range, the Mooney viscosity is less than 15, or the intrinsic viscosity is 1.
When it is less than 2, the impact strength is largely reduced, and when the Mooney viscosity is more than 45 or the intrinsic viscosity is 2.0.
When it is larger, the appearance (flow mark, gloss) of the bumper molded product deteriorates.

The talc (III) used in the present invention has an average particle size of 0.5 μ to 10 μ, preferably 0.5 μ to 5 μ.
is μ. If it is less than 0.5 μ, it tends to aggregate during kneading, and it is difficult to uniformly disperse it. If it is more than 10 μ, the impact strength is largely lowered and the appearance such as gloss is deteriorated. Talc may be used without any treatment, but various silane coupling agents, titanium coupling agents, higher fatty acids that are commonly known for the purpose of improving the interfacial adhesion with a polypropylene resin and improving the dispersibility. , Higher fatty acid ester,
A higher fatty acid amide, a higher fatty acid salt, or one whose surface is treated with another surfactant can be used.

When the propylene-ethylene block copolymer (I) is less than 50 parts by weight, the rigidity is low and the heat resistance is poor, and when it is more than 70 parts by weight, the impact strength at low temperature is low and the coating property is poor. . When the ethylene-propylene copolymer rubber (II) is less than 25 parts by weight, the impact strength at low temperature is low and the coatability is poor, and when it is more than 35 parts by weight, the rigidity is low. When the talc is less than 5% by weight, the rigidity is not sufficiently improved, and when it is more than 20 parts by weight, the impact strength is lowered.

In the present invention, (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate (hereinafter referred to as "compound (IV)") and the general formula

[Chemical 7] (In the formula, R ₁ is a methyl group, a tertiary butyl group, or a tertiary group.
Indicates an amyl group. R ₂ represents a hydrogen atom, a methyl group, a tertiary butyl group, a tertiary amyl group, a phenyl group or a cyclohexyl group. R ₃ represents a hydrogen atom, a methyl group, or a tert-butyl group. R ₄ is hydrogen atom, methyl group or tertiary
A butyl group is shown. However, R ₂ , R ₃ and R ₄ do not all represent hydrogen atoms at the same time. ) The pentaerythritol diphosphite compound represented by the formula (hereinafter referred to as “compound (V)”) is used.

The addition amount of these is the case of the compound (IV) based on 100 parts by weight of the total amount of the propylene-ethylene block copolymer (I), the ethylene-propylene copolymer rubber (II) and the talc (III). 0.01 to 0.5 part by weight, preferably 0.05 to 0.3 part by weight, and in the case of the compound (V), 0.03 to 0.3 part by weight, preferably
It is 0.05 to 0.3 parts by weight.

If the added amounts of the compound (IV) and the compound (V) both exceed the above-mentioned added amount ranges, these additives bleed out on the surface of the product and the coating property deteriorates. On the other hand, if the amount is less than the above range, the heat resistance will be poor.

Examples of phenylbenzoate compounds (hereinafter referred to as "compound (VI)") used in the present invention include phenyl salicylate, P-butylphenyl salicylate, P-octylphenyl salicylate, and resorcinol monobenzo. Eight, 2,4-di-t-butyl-phenyl-3,5-di-t-butyl-4-hydroxybenzoate, 4-octylphenyl-3,5-di-t-butyl-
4-hydroxybenzoate etc. are mentioned. In particular, 2,4-di-t-butyl-phenyl-3,5-di-
t-Butyl-4-hydroxybenzoate is preferred.

The addition amount of the compound (VI) is such that the total amount of the propylene-ethylene block copolymer (I), the ethylene-propylene copolymer rubber (II) and the talc (III) is 10.
It is 0.01 to 0.5 part by weight, preferably 0.03 to 0.3 part by weight, based on 0 part by weight.

If the amount of compound (VI) added exceeds the above range, the amount of compound (VI) bleeds out on the surface of the product, deteriorating the coatability. On the other hand, if the amount added is less than the above range, the weather resistance will be poor.

The heterocyclic hindered amine compound (hereinafter referred to as "compound (VII)") is composed of a hindered amine nitrogen atom and optionally a 6-membered heterocycle containing another heteroatom, preferably nitrogen or oxygen.

As a specific example, bis- (2,2,6,6
-Tetramethyl-4-piperidyl) sepacate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, succinic acid and N- (2-hydroxyethyl) -2,
Polycondensate with 2,6,6 tetramethyl-4-hydroxypiperidine, 1,2,3,4-tetra (2,2,6,6
-Tetramethyl-4-piperidyl) -butanetetracarboxylate, 1,4-di- (2,2,6,6-tetramethyl-4-piperidyl) -2,3-putanedione, tris- (2,2,2 6,6-Tetramethyl-4-piperidyl) trimellitate, 1,2,2,6,6-pentamethyl-4-piperidyl stearate, 1,2,2,6,6
-Pentamethyl-4-piperidyl-n-octoate,
Bis- (1,2,2,6,6-pentamethyl-4-piperidyl) sepacate, tris- (2,2,6,6-tetramethyl-4-piperidyl) -nitrile acetate, 4
-Hydroxy-2,2,6,6-tetramethylpiperidine, 4-hydroxy-1,2,2,6,6-pentamethylpiperidine, poly [(6-morpholino-S-triazine-2,4-diyl) [(2,2,6,6-Tetramethyl-4-piperidyl) imino] -hexamethylene [(2,2,6,6-tetramethyl-4-piperidyl)
Imino]], poly [[6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4
-Diyl] [2,2,6,6-tetramethyl-4-piperidyl) imino] hexamethylene [(2,2,6,6-
Tetramethyl-4-piperidyl) amino]], N, N ′
Examples include polycondensates of -bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine and 1,2-dibromoethane.

The addition amount of the compound (VII) is such that the total amount of the propylene-ethylene block copolymer (I), the ethylene-propylene copolymer rubber (II) and the talc (III) is 10.
It is 0.01 to 0.5 part by weight, preferably 0.03 to 0.3 part by weight, based on 0 part by weight.

If the added amount of the compound (VII) exceeds the above-mentioned added amount range, it bleeds out on the surface of the product and the coating property is deteriorated. On the other hand, if the amount added is less than the above range, the weather resistance will be poor.

The compound (IX) represented by the general formula 6 used in the present invention is dilauryl-thio-
Mention may be made of dipropionate, dimyristyl-thio-dipropionate, distearyl-thio-dipropionate. These thioester compounds have a heat resistance improving effect, but when the addition amount is too large, problems of odor deterioration and bleed-out occur, and weather resistance is significantly impaired, so addition of this is a heterocyclic hindered amine type compound. It should be 1/3 or less with respect to the amount of the compound (VII) added.

Specific examples of the compound (VIII) represented by the general formula 5 used in the present invention include methylenebisstearylamide, ethylenebisstearylamide, ethylenebisoleylamide, hexamethylenebisstearylamide and the like.

The compound (VIII) is added in a total amount of 1 of the propylene-ethylene block copolymer (I), ethylene-propylene copolymer rubber (II) and talc (III).
It is 0.01 to 0.5 parts by weight, preferably 0.03 to 0.3 parts by weight, based on 00 parts by weight. If the added amount of the compound (VIII) exceeds the above-mentioned added amount range, it bleeds out on the surface of the product and the paintability deteriorates. On the other hand, if the amount is less than the above range, the heat resistance and weather resistance cannot be improved.

By blending the compounds (IV) to (IX) as described above to obtain a propylene resin composition, the light stability can be improved without impairing the physical properties and coating properties. As an additional feature, the dispersibility of the inorganic filler is improved and the impact strength is also improved.

Various pigments can be added to the composition for coloring in order to improve the appearance and appearance of the molded article made of the composition of the present invention.

As the pigment used in the present invention, an inorganic pigment or an organic head material suitable for polyolefin can be used. For example, titanium oxide, carbon black, yellow iron oxide, titanium yellow, Hansa yellow, benzine yellow, red iron oxide, permanent red, thioindigo red, thioindigo maroon, manganese purple, dioxazine violet, ultramarine, phthalocyanine blue, phthalocyanine green, isoindo. Linone yellow, quinophthalone yellow, condensed azo yellow, perinone orange, quinacridone red, quinacridone scarlet, perylene red, perylene scarlet condensed azo red, dioxazine violet, indanthrone blue, sinkassia red, carbon black, titanium oxide, etc. . As the dispersant for the pigment, metal soaps such as calcium stearate and magnesium stearate, polyethylene wax, polypropylene wax and the like are used. In order to enhance the dispersion effect of the polyolefin wax, it is preferable to mix the pigment and the wax in advance with a powder ball mill or the like before use.

Others In the composition of the present invention, other additives such as process oils, plasticizers, lubricating oils, lubricants, nucleating agents, antistatic agents, mold release agents and fungicides can be added to the composition of the present invention, as long as the characteristics thereof are not impaired. Etc. can be added. Antioxidants other than those used in the composition of the present invention may be added as long as the characteristics are not impaired.

The composition of the present invention comprises a single-screw extruder, a twin-screw extruder,
It can be obtained by kneading in a heat-melted state using an ordinary kneading machine such as a Banbury mixer roll, Brabender, kneader and the like.

The resin composition according to the present invention can be obtained by injection molding, extrusion molding or blow molding. Injection molding is particularly suitable as a molding method. The resin composition has, for example, a flexural modulus of 8,000 k as a rigidity, for use as a bumper for automobiles.
g / cm ² or more, low-temperature impact strength: Izod impact strength at -30 ° C (with notch) is 10 kg ・ cm / cm or more, and the number of peels in the scoring peel test by the paintability test is zero. It is necessary to have excellent appearance such as high gloss and no flow mark. On top of this
To improve the processability during injection molding, the melt index of the resin composition must be 7 g / 10 minutes or more.

The propylene resin composition of the present invention has an excellent balance of rigidity and low temperature impact strength, is excellent in coatability, and is excellent in processability during injection molding and appearance of a molded product, so that the molding cycle is shortened. It is possible to reduce the wall thickness and make it applicable to bumper materials for automobiles, especially large bumpers that require fluidity.

[0038]

EXAMPLES The contents of the present invention will be specifically described below with reference to examples, but the scope is not limited thereby.

The measurement of physical properties according to the present invention is carried out by the following methods. Melt index: Compliant with JIS K-6758.

Flexural modulus: 23 ° C. according to ASTM D790
It was measured at. The test piece for measurement was molded using a screw in-line type injection molding machine manufactured by Sumitomo Heavy Industries, Ltd.

Izod impact strength (with notch): JIS K7
According to 110, it measured at 23 degreeC and -30 degreeC. The test piece for measurement was molded in the same manner as the test piece for measuring flexural modulus.

Gloss: According to ASTM D532-53T. A test piece for measurement was formed into a sheet having a thickness of 2 mm using a screw in-line type injection molding machine manufactured by Sumitomo Heavy Industries, Ltd.

Flow mark: Width 100 mm, using a screw in-line type injection molding machine manufactured by Sumitomo Heavy Industries, Ltd.
A sheet having a length of 400 mm and a thickness of 3 mm was formed. The generation of flow marks was visually observed and the following judgments were made.

Wave length: 25 mm wide x 1060 mm long x thickness 2. using a screw in-line type injection molding machine manufactured by Japan Steel Works
Injection pressure 700 kg / cm ² , injection time 8 with 0 mm mold
Molding was performed under conditions of a mold temperature of 50 ° C. for a second and a molding temperature of 250 ° C., and the length (mm) of the fluid was measured and used as a measure of workability.

Molding of bumper: Molded using a screw in-line type injection molding machine (UBEMAX2000 type) manufactured by Ube Industries, Ltd. to obtain a bumper molded product.

Bumper molded product pendulum test: FM
According to the method specified in VSS 581. An impact test was performed on the bumper molded product obtained by the above injection molding. The measurement temperature was −30 ° C., and the effective impact mass was 1000 kg.

Initial adhesion of coating of bumper molded product: A cut-out piece of the bumper molded product obtained by the above injection molding was used as a test piece, and the test piece was placed in 1,1,1-trichloroethane vapor (74 ° C). After cleaning the surface for 30 seconds and drying at room temperature, RB29 manufactured by Nippon Bee Chemical Co., Ltd. as a primer
1H is coated and baked in an oven at 100 ° C for 20 minutes, and then a urethane coating (Flexen # 101 manufactured by Nippon Bee Chemical Co., Ltd.) is spray-coated at 120 ° C.
Baking finish was performed for 40 minutes in the oven. Apply a razor blade to the coating film of this coating test piece to make a 2 mm square 1
After carving 00 pieces (10 length x 10 width), a cellophane tape [registered trademark] having a width of 24 mm (manufactured by Nichiban Co., Ltd.) was crimped on it with fingers, and then the end surface was grasped and left at a stretch. The number of goggles was evaluated as the residual rate (%).

Coating discoloration test: After the coating film coated by the above method was subjected to an acceleration test at 80 ° C. and 240 hr, the discoloration degree (ΔE) before and after the acceleration test was determined. △ E is ASTM D1365-5
It was measured from 5T with an SM color computer manufactured by Suga Test Instruments Co., Ltd. It was calculated from the following equation from the change amounts of L, a, and b before and after acceleration.

[0049]

[Formula 2]

Here, ΔL, Δa, and Δb are the lightness before and after the accelerated test, a is the chromaticity along the red-green axis, and b is the amount of change in the chromaticity along the yellow-blue axis.

(Thermal Oxidation Stability Test Method) Evaluation was carried out in accordance with JIS K 7212 [General heat aging test method for thermoplastics (oven method)]. Toyo Seiki Co., Ltd.
Measurement was performed at 150 ° C. using a gear oven. Then, the time (GO life) until the test piece (1 mm thick pressed sheet) was completely deteriorated, in other words, the tensile strength became zero, was measured.

(Light stability test method) manufactured by Suga Test Instruments Co., Ltd.
An accelerated light resistance test was performed using a sunshine super long life weather meter (WEL-SUN-DC type).
Then, the time taken for appearance abnormality such as cracks on the surface of the test piece was measured. The test conditions are shown below. (1) Specimen size: 70 mm x 25 mm x 1 mm (thickness) press sheet (2) Black panel temperature: 83 ° C (3) Spray / dry cycle: 18 minutes / 120 minutes (4) Humidity in test equipment tank: 50 % RH (5) Observation of abnormal appearance such as cracks: Observation with a microscope (× 50)

Example 1 The melt index was 20 g / 10 minutes, and the ethylene content was
9.5% by weight, the ethylene content in the propylene-ethylene copolymerization part is 53% by weight, and the intrinsic viscosity of the copolymerization part is 5.5 dl
/ G propylene-ethylene block copolymer (P
Let P-1. ) And ethylene content 50% by weight, Mooney viscosity ML _{1 + 4} 100 ℃ 29, intrinsic viscosity 1.47dl / g
Ethylene propylene copolymer rubber (referred to as EPR-1) and talc having an average particle size of 3 μm are 6
The propylene resin composition was mixed at a ratio of 5:25:10 (parts by weight), and further mixed with the compounding recipe shown in Table 1 with respect to 100 parts by weight of the total amount of the above components at 190 ° C. for 10 minutes with a Banbury mixer. Kneaded After kneading, the pelletized product was molded with an extruder, and the physical property measurement results are shown in Table 2. A large bumper (weight: 2800 g) for an automobile was obtained by molding the resin composition with a UBEMAX 2000 type injection molding machine at a molding temperature of 240 ° C., a mold temperature of 40 ° C., an injection time of 25 sec, and a cooling time of 60 sec. When the appearance of the molded product was observed with the naked eye, there was no flow mark and a molded product with good gloss was obtained.

Further, the pendulum test, the initial coating adhesion and the discoloration of the coating film were evaluated using the bumper molded product, and the results are shown in Table 2. Table 2 shows the test results of thermal oxidation stability and photostability.

Example 2 Evaluation was carried out in the same manner as in Example 1 with the formulation shown in Table 1. The evaluation results are shown in Table 2.

Example 3 Instead of EPR-1, an ethylene-propylene copolymer rubber (EPR-2) having an ethylene content of 70% by weight, a Mooney viscosity ML _{1 + 4 of} 100 ° C. of 22 and an intrinsic viscosity of 1.32 dl / g was used. The same evaluation as in Example 1 was carried out except that the results were shown in Table 2.
It was shown to.

Comparative Example 1 Instead of PP-1, the melt index was 7.0 g / 1.
0 minutes, the ethylene content is 8.0% by weight, the ethylene content in the propylene-ethylene copolymer part is 45% by weight, and the intrinsic viscosity of the copolymer part is 6.5 dl / g. (PP-2) and EPR
Instead of -1, an ethylene-propylene copolymer rubber (referred to as EPR-3) having an ethylene content of 49% by weight, a Mooney viscosity ML _{1 + 4} 100 ° C of 80 and an intrinsic viscosity of 2.50 dl / g is used. A resin composition having the composition shown in Table 1 was obtained in the same manner as in Example 1 except that the resin composition was used. The evaluation results are shown in Table 2.

Comparative Example 2 Instead of PP-1, the melt index was 46 g / 1.
Propylene-ethylene block copolymer having 0 minutes, an ethylene content of 9.0% by weight, an ethylene content of 51% by weight in a propylene-ethylene copolymer part, and an intrinsic viscosity of the copolymer part of 6.0 dl / g. (PP-3) and EPR-1.
Table 2 shows the evaluation results obtained by obtaining resin compositions having the compositions shown in Table 1 except that EPR-2 was used instead of.

Comparative Example 3 The procedure of Example 1 was repeated except that the mixing ratios of PP-1, EPR-1 and talc were changed to 70:20:10, and the results are shown in Table 2.

[0060]

[Table 1]

[0061]

[Table 2]

Examples 4 to 6 Resin compositions were obtained according to the formulations shown in Table 3 and evaluated in the same manner as in Example 1. The results are shown in Table 4.

Comparative Examples 4 to 8 Resin compositions were obtained according to the formulations shown in Table 3 and evaluated in the same manner as in Example 1. The results are shown in Table 4.

Compounds (IV) to (I in Tables 1 and 3)
X) is as follows. Compound IV: tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate Compound IV ′: pentaerythrityl-tetrakis [3- (3,5-
Di-t-butyl-4-hydroxyphenylpropionate] Compound V: bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite Compound VI: 2,4-di-t-butylphenyl-3, 5-Di-t-butyl-4-hydroxybenzoate compound VI ′: 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole compound VII: bis- (2,2 , 6,6-Tetramethyl-4-pyridyl) sebacate Compound VIII: Ethylenebisstearylamide Compound IX: Dimyristyl-3,3-thiodipropionate

[0065]

[Table 3]

[0066]

[Table 4]

Example 7 Using the bumper molded product of Example 1, the coating method was changed to the following method to coat a test piece. 1,1,1-Trichloroethane The surface of the test piece was washed in the above (74 ℃) for 30 seconds, dried at room temperature, and then plasma treated (Toshiba TMZ-9602C,
Plasma treatment was carried out using a volume of 75.4 liters).
The plasma processing conditions were as follows. Shower tube: 200 W Vacuum degree: 2 Torr Gas flow rate: 110 cc / min (O ₂ / N ₂ = 10/1) Treatment time: 15 sec After plasma treatment, urethane-based paint (Nippon Bee Chemical Co., Flexen # 101) ) Was spray-painted and baked for 40 minutes in an oven at 120 ° C. After coating, the coating film was subjected to a peeling test, and the residual rate was 100%.

Comparative Example 9 As a bumper molded product obtained in Comparative Example 8, a test piece was coated by the coating method of Example 7 and then subjected to a goggles peeling test of the coating film to find a residual rate of 87%.

[0069]

The present invention has excellent rigidity and impact resistance,
In addition, a resin composition having excellent heat resistance, weather resistance and coatability can be obtained.

Claims (1)

[Claims] 1. The melt index (I) is 15 to 30.
(G / 10 minutes), the ethylene content is 5 to 15% by weight, and the ethylene content of the propylene-ethylene copolymerization part is 30 to 60.
50% to 70% by weight of a propylene-ethylene block copolymer having an intrinsic viscosity of 4% to 10 (dl / g) in a 135 ° C. tetralin solution of the copolymerized portion, and (II) an ethylene content of 40 to 80% by weight. % By weight, Mooney viscosity ML _{1 + 4} 100
25 to 35 parts by weight of ethylene-propylene copolymer rubber having an intrinsic viscosity of 1.2 to 2.0 (dl / g) at a temperature of 15 to 45 ° C. and a 70 ° C. xylene solution, and (III) an average particle diameter of For 100 parts by weight of a resin composition consisting of 5 to 20 parts by weight of talc of 0.5 to 10 μm, (IV) tris (3,5-
0.01-0.5 parts by weight of di-t-butyl-4-hydroxybenzyl) isocyanurate, (V) the following general formula: (In the formula, R ₁ is a methyl group, a tertiary butyl group, or a tertiary group.
Indicates an amyl group. R ₂ represents a hydrogen atom, a methyl group, a tertiary butyl group, a tertiary amyl group, a phenyl group or a cyclohexyl group. R ₃ represents a hydrogen atom, a methyl group, or a tert-butyl group. R ₄ is hydrogen atom, methyl group or tertiary
A butyl group is shown. However, R ₂ , R ₃ and R ₄ do not all represent hydrogen atoms at the same time. ) Pentaerythritol diphosphite compound 0.03-0.
3 parts by weight, (VI) phenyl benzoate compound 0.0
1 to 0.5 parts by weight, (VII) 0.01 to 0.5 parts by weight of a heterocyclic hindered amine compound, and (VII
I) the following general formula ## STR2 ## _{R 7 -CO-NH- (CH 2} ) n -HN-CO-R 7 ( wherein, R ₇ represents an alkyl or alkenyl group having 5 to 21 carbon atoms .n 0.01 to 0.5 part by weight of a compound represented by the formula (1) to (6), and (IX) the following general formula: (In the formula, R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group or an aryl group;
₅ and R ₆ may be the same or different. ) A propylene resin composition comprising a compound represented by the formula (1) in an amount of 1/3 or less of the heterocyclic hindered amine compound (VII).