JPH0678455B2 - Propylene polymer composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a propylene-based polymer composition having excellent adhesion to polyurethane without using a primer.
More specifically, (A) (1) a propylene-based polymer is treated with (2) an organic compound having at least one unsaturated bond in the molecule and containing a hydroxyl group, and (3) an organic peroxide. A propylene comprising a modified propylene polymer obtained by the above, (B) homo- or random copolymer of pyropyrene, (C) an amorphous ethylene-propylene copolymer having a Mooney viscosity of 20 to 100, and (D) an inorganic filler. It is related to the polymer composition, not only has excellent mechanical properties such as rigidity and low temperature impact resistance, but also has good adhesion to polyurethane without the use of a primer, and also has excellent weather resistance. The object is to provide an excellent propylene polymer composition.

As is well known, propylene-based polymers (propylene homopolymers and propylene copolymers) have not only excellent moldability but also mechanical properties, heat resistance, solvent resistance, oil resistance and chemical resistance. Because of such good characteristics, it is widely manufactured industrially and widely used in various fields as industrial parts such as automobiles, electric appliances, electronic devices and daily necessities. However, since it does not have a polar group in the molecule (so-called non-polar), the adhesion to polyurethane is not good, which causes various problems. With respect to this, a widely used automobile bumper will be described as an example.

Conventionally, bumpers made of metal or polyurethane have been widely used. In recent years, a propylene-based polymer (propylene homopolymer, ethylene-propylene random or block copolymer) containing propylene as a main component or a composition containing a propylene-based polymer as a main component, aiming at weight reduction and cost reduction of automobiles. Bumpers made from objects are widely used. In many cases, this bumper is used as it is without being painted, because the surface of the molded product is pre-textured before it is mounted on the vehicle. However, in order to make the bumper even more fresh and luxurious, it is often the case that polyurethane is applied to the bumper and it is mounted on the vehicle, and the proportion is increasing further in the direction of upsizing of the automobile.

However, as mentioned above, propylene-based polymers are chemically extremely inactive polymeric substances because they do not have polar groups in the molecule. Methods of treating by surface treatment methods such as a corona discharge treatment method, a plasma treatment method, a mechanical surface roughening method, a flame treatment method and an oxygen or ozone treatment method are well known. Further, it is recommended to wash the surface with a solvent such as alcohol or aromatic hydrocarbon prior to the surface treatment. Furthermore, there is also known a method of immersing a molded article in an organic solvent such as trichlene, perchlorethylene, pentachlorethylene and toluene at a temperature close to the boiling point or exposing the molded article to a solvent vapor (for example, Kenyuki Takagi, Taira Sasaki). Three Editors, "Plastic Materials Course, Polypropylene Resin", pp.216-219
Page, 1969, published by Nikkan Kogyo Shimbun). However, not only do these methods require equipment for processing, but they also take a considerable amount of time.

Furthermore, it is a reality that a molded article (bumper) is undercoated with a primer capable of adhering to a propylene-based polymer, and a polyurethane coating is applied as an overcoat. That is, the steps of primer undercoating → baking → polyurethane coating → baking (2 coat 2 bake or 3 coat 2 bake) must be performed, and this coating process takes a long time (usually about 1
I need 30 minutes). For this reason, it takes a long coating cycle to manufacture a bumper coated with this polyurethane, which not only makes mass production difficult but also increases the cost.

When manufacturing other automobile parts, tricycle parts, electric appliance parts, electronic appliance parts, etc., when applying propylene polymer and applying polyurethane, the application method is different, but there are the same problems as above. .

Generally, polypropylene or a composition thereof used for bumpers and the like has a combination of an ultraviolet absorber, an ultraviolet stabilizer, an antioxidant and the like added in an arbitrary formulation in order to enhance weather resistance. However, after several years in an actual vehicle, the surface of the molded product is discolored, and chalking or cracks occur, which is not sufficient at present. further,
The demand for bumper grades with good weather resistance is becoming stronger as automobiles become more upscale and used in rural areas where the climate is bad.

Therefore, as a countermeasure, it is conceivable to increase the conventional weather resistance formulation or add a new additive, but if these are simply increased or added, appearance problems at the time of molding (for example, uneven gloss on the surface or whitening) There are various problems such as the cause of the above, bleeding of the additive added or added to the surface of the molded article after molding, the appearance is deteriorated, and the surface of the molded article is whitened by long-term use in an actual vehicle.

Problems to be Solved by the Invention From the above, the present invention does not have these problems (deficiencies), that is, does it retain various mechanical properties (for example, impact strength, rigidity) having a propylene-based polymer? Another object of the present invention is to obtain a propylene-based polymer composition which is not only improved, but also has good moldability and excellent weather resistance, and at the same time is capable of adhering to polyurethane without using a primer.

Means and Actions for Solving Problems According to the present invention, the problems are (A) (1) a mixture of a propylene polymer or a propylene homopolymer and an ethylene-propylene copolymer rubber.
100 parts by weight (2) "has at least one unsaturated bond in the molecule,
And a hydroxyl group-containing organic compound "(hereinafter referred to as" hydroxyl compound ") 0.1 to 50 parts by weight and (3) 0.01 to 20 parts by weight of organic peroxide. (B) a propylene homopolymer or a random copolymer of propylene as a main component with ethylene and / or an α-olefin (C) a Mooney viscosity [ML _{1 + 4} , (100 ° C.)] of 20 to 100, A composition comprising an amorphous ethylene-propylene copolymer having a propylene content of 20 to 50% by weight and (D) an inorganic filler, wherein the composition ratio of the (D) component in the composition is 2.0 to 40% by weight, the ratio of the component (A) and the component (2) with respect to 100 parts by weight of the total amount of the components (A) and (B) is 0.01 to 10.0 parts by weight as a monomer unit, and B) The composition ratio of the component (A) in the total amount of is 5 to 90% by weight, the composition ratio of the component (A) in the composition is at least 5.0% by weight, and the composition ratio of the component (C) is 1.0 wt% to 15
A propylene-based polymer composition that is less than wt%.

Can be solved by. Hereinafter, the present invention will be specifically described.

(A) Modified propylene-based polymer The modified propylene-based polymer of the present invention is a mixture of a propylene-based polymer or a propylene homopolymer described below and an ethylene-propylene-based copolymer gum, which is treated with a hydroxylated compound and an organic peracid compound. The method for producing the same is described in JP-A-58-154732.
It is described in detail in the specification of the gazette.

(1) Propylene-based polymer The propylene-based polymer used for producing the modified propylene-based polymer of the present invention is a propylene homopolymer, a block copolymer of ethylene containing propylene as a main component and / or an α-olefin. It is selected from a combination and a random copolymer mainly composed of propylene and ethylene and / or α-olefin. In both these block copolymers and random copolymers, the copolymerization ratio of ethylene and α-olefins is at most 20%.
% By weight (preferably 15% by weight or less). Also, α
The olefin has 4 to 12 carbon atoms. Typical examples of the α-olefin include butene-1, hexene-1, 4-
Methylhexene-1 and octene-1 are mentioned.

These propylene-based polymers are industrially produced and used in various fields. The physical properties and production method of these propylene-based polymers are well known.

Further, instead of the propylene-based polymer, it is also possible to use a mixture of a propylene homopolymer and an ethylene-propylene-based copolymer rubber described below in a composition ratio described below. At this time, the ethylene-propylene copolymer rubber used has ethylene and propylene as main components. Examples of the ethylene-propylene copolymer rubber include the amorphous ethylene-propylene copolymers described later (the same type or different types may be used). Among these ethylene-propylene copolymers, the content of propylene is 20 to 80% by weight both in the case of copolymer rubber and in the case of multi-component copolymer rubber. Also, the Mooney viscosity [ML
_{1 + 4} , (100 ° C)] is 10 to 50, preferably 10 to 40,
Especially, 15 to 40 is preferable. When an ethylene-propylene copolymer rubber having a Mooney viscosity of less than 10 is used, the moldability is good, but the adhesion strength with the urethane coating described later is not sufficiently improved. On the other hand, if it exceeds 50, flow marks and the like are generated on the surface of the molded product, which is not preferable in appearance.

In producing the modified propylene-based polymer of the present invention,
The proportion of the ethylene-propylene copolymer rubber in the total amount of the propylene homopolymer and the rubber of the ethylene-propylene copolymer is usually at most 40% by weight, preferably 1 to 40% by weight, and particularly 2 ~ 35 wt% is preferred. When the proportion of the ethylene-propylene copolymer rubber in the total amount of the propylene homopolymer and the ethylene-propylene copolymer rubber exceeds 40% by weight, the adhesion strength with the coating film is good, but the molded product Not only flow marks are generated on the surface of the, but also the glossiness is deteriorated.

Melt flow rate of this propylene-based polymer (JIS
According to K7210, measured under condition 14, hereinafter referred to as "MFR") is usually 0.01 to 100 g / 10 minutes, 0.01 to 80 g / 10 minutes from the viewpoint of moldability, mechanical properties of the obtained composition, etc. It is preferably 0.02 to 60 g / 10 minutes.

(2) Hydroxyl compound Further, the hydroxyl compound is a compound having at least one unsaturated bond (double bond, triple bond) and containing a hydroxyl group. Typical examples thereof include an alcohol having a double bond, an alcohol having a triple bond, an ester of a monovalent or divalent unsaturated carboxylic acid and an unsubstituted dihydric alcohol, an unsaturated carboxylic acid and an unsubstituted trivalent alcohol. Examples thereof include esters with polyhydric alcohols, esters with unsubstituted tetrahydric alcohols, and esters with unsubstituted pentavalent or higher alcohols.

(3) Organic peroxide An organic oxide is generally used as an initiator in radical polymerization and a cross-linking agent for a polymer, and one having a half-life of 1 minute or more of 100 ° C or more is preferable, and A temperature of 130 ° C or higher is suitable. Above temperature is 100
If the temperature is lower than 0 ° C, not only is it difficult to handle, but also the effect of use is not so noticeable, which is not desirable.

(4) Mixing ratio In producing the mixture of the present invention, the mixing ratio of the hydroxyl compound to 100 parts by weight of the propylene polymer is 0.1 to 50 parts by weight, preferably 0.2 to 30 parts by weight, and particularly 0.3 to 20 parts by weight. Parts are preferred. Propylene polymer 100
Mixing ratio of hydroxyl compound to 0.1 part by weight is 0.1
When the amount is less than the weight part, the effect of improving the adhesion is insufficient. On the other hand, even if it is used in an amount of 50 parts by weight or more, the effect of improving the adhesiveness depending on the amount used is not recognized, and rather the original properties of the propylene monopolymer are impaired, which is not preferable.

The mixing ratio of the organic peroxide with respect to 100 parts by weight of the propylene-based polymer is 0.01 to 20 parts by weight, preferably 0.05 to 10 parts by weight, and particularly preferably 0.1 to 7 parts by weight.
When the mixing ratio of the organic peroxide to 100 parts by weight of the propylene-based polymer is 0.01 parts by weight or less, not only the effect of improving the adhesiveness is low, but also the durability of the adhesive strength of the mixture is reduced.
On the other hand, when the amount is 20 parts by weight or more, the excellent mechanical properties of the polymer in the future are deteriorated, and therefore, it is not desirable in any case.

(5) Method for producing modified propylene-based polymer In order to produce the modified propylene-based polymer of the present invention, the above propylene-based polymer, hydroxyl-based compound and organic peroxide are treated at the above mixing ratio (heating). Can be manufactured. At this time, the treatment may be carried out while mixing the propylene polymer, the hydroxyl compound and the organic peroxide, but these may be mixed in advance by dry blending, or at a relatively low temperature (a temperature at which the hydroxyl compound does not react). It can be obtained by kneading with and heating the resulting mixture as described below.

If the treatment is carried out at a high temperature, the propylene-based polymer may deteriorate. However, it must be carried out at a temperature at which the organic peroxide used for graft-polymerizing the propylene-based polymer and the hydroxyl-based compound used decomposes. From the above, this treatment is generally performed at 160-300 depending on the type of organic peroxide used.
It is carried out at ℃ (preferably 170 to 280 ℃).

The general formulas and typical examples of the hydroxyl compounds and organic peroxides, and the mixing method and treatment method are described in detail in JP-A-58-154732.

(B) homopolymer or random copolymer of propylene,
In the composition of the present invention, the modified propylene-based polymer, a propylene homopolymer or a random copolymer of propylene as a main component with ethylene and / or α-olefin (hereinafter, referred to as propylene-based polymer (B)). ) Are used, except for MFR, which are of the same kind as the homopolymer or random copolymer of propylene used in producing the modified propylene-based polymer (however, in the case of producing the modified propylene-based polymer, It does not have to be the same as it was). Of these propylene-based polymers (B), random copolymers are preferably used.

The MFR of this propylene polymer (B) is usually 1.0 to 100 g / 1.
0 minutes, 1.0-80g / 10 minutes is desirable, especially 2.0-6
0 g / 10 minutes is suitable. If the propylene-based polymer (B) having an MFR of less than 1.0 g / 10 minutes is used, not only the kneadability with the modified propylene-based polymer is poor, but also the moldability of the resulting composition is poor. On the other hand, when the propylene-based polymer (B) exceeding 100 g / 10 min is used, the mechanical strength of the obtained composition is not good.

(C) Amorphous Ethylene-Propylene Copolymer Further, the amorphous ethylene-propylene copolymer used in the present invention is a copolymer rubber obtained by copolymerizing ethylene and propylene, and ethylene and propylene. As the main component, 1,4-pentanediene, 1,5-hexadiene and a straight-chain or branched-chain diolefin containing two double bonds at the ends such as 3,3-dimethyl-1,5-hexadiene, Terminated linear or branched diolefins such as 1,4-hexadiene and 6-methyl-1,5-heptadiene or bicyclo [2,2,1] -heptene-2 (norbornene) and its derivatives (eg ethylidene) A small amount (generally 10% by weight or less) of a monomer having a double bond such as a cyclic diene hydrocarbon such as norbornene) It is roughly classified into multicomponent copolymer rubber obtained by the. Mooney viscosity of the amorphous ethylene-propylene copolymer [ML _{1 + 4} , (1
00 ° C)] is 20 to 100, preferably 20 to 80, and more preferably 30 to 75. If an amorphous ethylene-propylene copolymer with a Mooney viscosity of less than 20 is used, the molded product will improve, but layer separation may occur when the molded product is gate carted, which causes troubles. There is. On the other hand, if more than 100 is used, not only it becomes difficult to uniformly disperse with other composition components during kneading, but even if a uniform composition is obtained, a flow mark on the surface of the molded product, Conspicuous weld lines and the like make it difficult to obtain a molded product with a good appearance. Further, the propylene content of this copolymer is generally 20 to 50% by weight, preferably 25 to 45% by weight, and especially 25 to 40% by weight.
Weight% is preferred. This amorphous ethylene-propylene copolymer has rubber-like properties, is industrially produced and is used in various fields, and its manufacturing method is also widely known.

(D) Inorganic Filler The inorganic filler used in the present invention is generally widely used in the fields of synthetic resins and rubber. As these inorganic fillers, inorganic compounds that do not react with oxygen and water and that do not decompose during kneading and molding are preferably used. Examples of the inorganic filler include metals such as aluminum, copper, iron, lead and nickel, oxides of these metals and metals such as magnesium, calcium, barium, zinc, zirconium, molybdenum, silicon, antimony and titanium, and water thereof. Compounds such as hydrates (hydroxides), sulfates, carbonates and silicates, double salts thereof and mixtures thereof are roughly classified. Typical examples of the inorganic filler are described in Japanese Patent Application No. 59-8535. Of these inorganic fillers, powdery ones having a diameter of 30 μm or less (preferably 10 μm or less) are preferable. In the fibrous form, the diameter is preferably 1 to 500 μm (preferably 1 to 300 μm) and the length is preferably 0.1 to 6 mm (preferably 0.1 to 5 mm). Further, it is preferable that the flat plate has a diameter of 30 microns or less (preferably 10 microns or less). Of these inorganic fillers, flat plate-shaped (flake-shaped) and powdered ones are particularly preferable. Suitable inorganic fillers include ralc, mica, silica, glass fibers, graphite and the like.

(E) Composition Ratio The composition ratio of the inorganic filler in the composition obtained in the present invention is 2.0 to 40% by weight, preferably 2.5 to 35% by weight, and particularly preferably 3.0 to 30% by weight. When the composition ratio of the inorganic filler in this composition is less than 2.0% by weight,
The flexural modulus (rigidity) of the resulting composition is not improved.
On the other hand, if it exceeds 40% by weight, not only the impact resistance of the composition at low temperature is poor, but also silver may be generated during molding. There is a means of pre-drying the composition in order to prevent the generation of this silver, but this is not a good idea in mass production of large molded articles such as bumpers.

The composition ratio of the modified propylene polymer in the total amount (sum) of the modified propylene polymer and the propylene polymer (B) is 5 to 90% by weight, and 10 to 80% by weight.
Is preferable, and 20 to 60% by weight is particularly preferable. When the composition ratio of the modified propylene-based polymer in the total amount of the modified propylene-based polymer and the propylene-based polymer (B) is less than 5% by weight, the adhesiveness between the composition and the polyurethane is poor. On the other hand, if it exceeds 90% by weight, the impact resistance at low temperature becomes insufficient.

Furthermore, the composition ratio of the modified propylene-based polymer in the composition is at least 5% by weight, preferably 5 to 20% by weight, particularly preferably 5 to 15% by weight. When the composition ratio of the modified propylene polymer in the composition is less than 5% by weight, the adhesion between the composition and polyurethane is not good.

The composition ratio of the amorphous ethylene-propylene copolymer in the composition is 1.0% by weight to less than 15% by weight, preferably 2.0% by weight to less than 15% by weight, and more preferably 3.0% by weight to less than 15% by weight. Is the best. When the composition ratio of the amorphous ethylene-propylene copolymer in the composition is less than 1.0% by weight, the composition has poor impact resistance at low temperature. On the other hand, when the content exceeds 15% by weight, the impact resistance at low temperature is excellent, but the bending elastic modulus (rigidity) is low, which is not good in terms of balance.

Further, the ratio of the organic compound having a hydroxyl group to the total amount of 100 parts by weight of the modified propylene polymer and the propylene polymer (B) is 0.01 as a monomer unit.
-10.0 parts by weight, preferably 0.1-10.0 parts by weight, particularly preferably 0.2-5.0 parts by weight. If the proportion of the organic compound containing a hydroxyl group is less than 0.01 parts by weight per 100 parts by weight of the total amount of these polymers, the adhesiveness between the resulting composition and polyurethane will be insufficient. Further, even if the amount exceeds 10.0 parts by weight, the adhesion cannot be further improved.

(F) Production of Composition, Molding Method, etc. In order to produce the composition of the present invention, the modified propylene-based polymer, propylene-based polymer (B), amorphous ethylene-
The propylene copolymer and the inorganic filler may be uniformly mixed by applying a mixing method which is practiced in the field of ordinary olefin polymers so as to be within the above-mentioned composition ratio range. At this time, all composition components may be mixed at the same time, or a part of the composition components may be mixed in advance,
It is also possible to produce a so-called masterbatch and mix this masterbatch with the remaining constituents. At this time, stabilizers against heat, oxygen or ultraviolet rays, which are generally mixed (added) to olefin polymers, metal deterioration inhibitors, plasticizers, flame retardants, lubricants, fillers, colorants, antistatic agents, and You may mix | blend additives, such as an electrical property improver, according to the use purpose of a composition in the range which does not impair the physical properties of a composition essentially.

The composition thus obtained is usually molded into pellets, and is manufactured into a desired molded product by a molding method such as an injection molding method or an extrusion molding method that is generally performed in the field of each thermoplastic resin.

Even when melt-kneading when producing the composition,
Even in the case of molding, the temperature is higher than the melting point of the polymer used, but is a temperature at which thermal decomposition does not occur. For these reasons, it is generally carried out at 180 to 300 ° C (preferably 190 to 250 ° C).

Generally, olefin polymers have extremely poor adhesion to polyurethane, so when applying a polyurethane paint to a molded product of an olefin polymer or a composition thereof, a primer must be applied and dried in advance to apply the polyurethane paint. I have to. However, since the propylene-based polymer composition of the present invention has excellent adhesion to polyurethane, it is possible to directly apply polyurethane to the surface of a molded article without applying a primer to the surface of the molded article (primer). Is used, the adhesion is further improved).

Further, the flexural modulus is 9,000 kg / cm ² or more, and the Izod impact strength (with notch) at −30 ° C. is 8 kg · cm / cm. Furthermore, the melt flow index is 5g / 10 minutes or more.

Examples and Comparative Examples Hereinafter, the present invention will be described in more detail with reference to Examples.

In Examples and Comparative Examples, the flexural modulus is ASTM
Measured according to D790, Izod impact strength is ASTM
Measured according to D256. In addition, the coating film adhesion strength was determined by placing a flat plate test piece (thickness: 2 mm, 130 x 130 mm) in steam of 1,1,1-trichloroethane for 30 seconds and allowing it to dry sufficiently before using a high urethane coating (Nippon Pee Chemical Co., Ltd.). Product name, R25
7, solid) was applied so that the thickness when dried was 20 to 30 microns. After leaving for about 15 minutes, urethane paint (product name, R266, Wacker Top, manufactured by Nippon Pea Chemicals Co., Ltd.)
To a dry thickness of 30-40 microns,
It was dried at 90 ° C. for 30 minutes. Then, at room temperature (temperature
It was left for 48 hours at 23 ° C and 65% humidity. The obtained coated product (test piece) is cut into a width of 10 mm, a part (about 10 mm) of the coating film is forcibly peeled from the resin portion of the test piece, and the remaining adhesion portion is used by a tensile tester. It was obtained by pulling in the opposite direction (180 degrees) to the coating film at a speed of 50 mm / min and measuring the peel strength. Further, in the weather resistance test, the flat plate test piece was cut into 50 mm x 50 mm, and the black panel temperature was 83 ° C using a sunshine weatherometer (manufactured by Suga Test Instruments).
Irradiation was carried out under the conditions of 12 minutes / 60 minutes and the rainfall conditions, and the samples were taken out at each irradiation time, and changes in the appearance of the sample were observed. The results are shown below.

⊚: No change ◯: Slight chalking Δ: Cracking ×: Violent cracking In addition, the modified propylene-based polymer (B), pyropyrene-based polymer (B), and amorphous ethylene used in Examples and Comparative Examples The physical properties of the propylene copolymer rubber, the inorganic filler, and other composition components, the manufacturing method, and the like are shown below.

[Modified propylene homopolymer] As a modified propylene homopolymer, 85 parts by weight of propylene homopolymer having an MFR of 0.5 g / 10 minutes and Mooney viscosity (ML
_{1 + 4} , 100 ° C.) 20 Amorphous ethylene-propylene copolymer 15 parts by weight to 3.0 parts by weight of 2-hydroxyethyl methacrylate and 0.7 parts by weight of 2,2′-bis (tertiary-butylperoxide) Oxyisopropyl) benzene was previously dry blended for 5 minutes using a Henschel mixer. What was obtained by kneading the obtained mixture using a vented extruder (diameter 65 mm, cylinder temperature 160 to 200 ° C.) (referred to as “modified PP”) was used.

[Propylene homopolymer]

As the propylene homopolymer, a propylene homopolymer having an MFR of 10 g / 10 minutes [hereinafter referred to as "PP (1)"] was used.

[Ethylene-Popylene Random Copolymer]

An ethylene-propylene random copolymer having an ethylene content of 3.1% by weight [hereinafter referred to as "PP (2)"] was used.

[Amorphous ethylene-propylene copolymer]

As an amorphous ethylene-propylene copolymer, amorphous ethylene-having a Mooney viscosity [ML _{1 + 4} , (100 ° C)] of 35
A propylene copolymer (content of propylene of 27% by weight, hereinafter referred to as "EPR") was used.

[Inorganic filler]

As the inorganic filler, talc having an average particle diameter of 2.0 μm, calcium carbonate (hereinafter referred to as “CaCO ₃ ”) having an average particle diameter of 2.0 μm, and wollastonite having an average particle diameter of 7.0 μm were used.

[Stabilizer]

As various stabilizers, bis (2,2,6,6-tetramethyl-4
-Piperidine sebacate [hereinafter referred to as "stabilizer (1)"] 2 (3-tertiary-butyl-5-methyl-2-hydroxyphenyl-5-chlorobenzotriazole [hereinafter referred to as "stabilizer (2)" ] And tetra [methylene-3
-(3,5-ditertiary-butyl-4-hydroxyphenyl) propionate] methane [hereinafter referred to as "stabilizer (3)"] was used.

Examples 1 to 13 and Comparative Examples 1 to 3 Modified propylene-based polymers, ethylene-propylene random copolymers, the blending amounts of which are shown in Table 1,
Propylene homopolymer, amorphous ethylene-propylene copolymer and talc (as an inorganic filler) were mixed for 5 minutes using a super mixer. A twin screw extruder with vent (cylinder temperature 180-200 ℃, diameter 30m
Pellets (composition) were produced while kneading using m). A flat plate (thickness: 2 mm, 130 × 130 mm), a bending elastic modulus measuring sample, and an Izod impact strength measuring sample were manufactured from each pellet by using a 5 ounce injection molding machine.
The coating film adhesion strength, Izod impact strength (temperature: 23 ° C.), weather resistance test and flexural modulus of each of the obtained test pieces were measured. The results are shown in Table 2.

From the results of the above Examples and Comparative Examples, the propylene-based polymer composition obtained by the present invention has not only excellent mechanical strength (flexural modulus, impact resistance) but also good processability. It is also clear that the adhesiveness with polyurethane is also excellent. Furthermore, it is clear that the most characteristic effect is that when a stabilizer against heat, oxygen and ultraviolet rays is added, a synergistic effect is exerted.

Effects of the Invention The propylene-based polymer composition obtained by the present invention is
Compared with the conventional propylene polymer composition, the following effects are exhibited.

(1) Workability and moldability are equal or higher.

(2) The weather resistance exerts a synergistic effect as described above and is good.

(3) The adhesiveness with the polyurethane paint is excellent, and the primer undercoating step can be omitted by applying the polyurethane paint on the surface.

(4) A commonly used activation treatment method (for example,
Corona discharge treatment, plasma treatment method, ultraviolet treatment method) can be applied to the surface of the molded article to further improve the adhesion to the polyurethane coating.

The propylene-based polymer composition of the present invention can be used in various fields in order to exert the above effects. Typical applications include exterior parts such as automobile bumpers and bumper corners, interior parts such as door liners, and motorcycle parts such as fenders.

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location // (C08L 23/10 51:06 23:16) (56) References JP-A-60-55052 (JP, A) JP 62-64848 (JP, A) JP 62-119243 (JP, A) JP 62-257945 (JP, A)

Claims (1)

[Claims] (1) 100 parts by weight of a mixture of (A) (1) a propylene polymer or a propylene homopolymer and an ethylene-propylene copolymer rubber (2) having at least one unsaturated bond in the molecule A modified propylene polymer obtained by treating 0.1 to 50 parts by weight of a hydroxyl group-containing organic compound and (3) 0.01 to 20 parts by weight of an organic peroxide, and (B) a propylene homopolymer or propylene. Random copolymer with ethylene and / or α-olefin as main component (C) Mooney viscosity [ML _{1 + 4} , (100 ° C)] is 20 to 100 and propylene content is 20 to 50 weight. % Of the amorphous ethylene-propylene copolymer and (D) the inorganic filler, the composition ratio of the (D) component in the composition is 2.0 to 40% by weight, and the (A) composition The ratio of the component (A) (2) to the total amount of 100 parts by weight of the component and the component (B) is 0.01 to 10.0 parts by weight as a monomer unit, and occupies in the total amount of the components (A) and (B). The composition ratio of the component (A) is 5 to 90% by weight, and the composition ratio of the component (A) in the composition is at least 5.0% by weight.
And the composition ratio of the component (C) is 1.0% by weight to 1
A propylene-based polymer composition containing less than 5% by weight.