JPS62119243A - Propylene polymer composition - Google Patents

Abstract

PURPOSE:To obtain a composition having good moldability and giving a molded article having excellent appearance, by compounding a specific modified propylene polymer, a specific crystalline ethylene-propylene block copolymer, a specific ethylene-propylene copolymer and a filler. CONSTITUTION:The objective composition can be produced by compounding (A) a modified propylene polymer produced by treating 100pts.(wt.) of a propylene homopolymer and an ethylene-propylene copolymer rubber with 0.1-50pts. of an organic compound containing unsaturated bond and hydroxyl group and 0.01-20pts. of an organic peroxide, (B) a crystalline ethylene- propylene block copolymer having an MFR of 2.0-100g/10min and an ethylene content of 2-15wt%, (C) an amorphous ethylene-propylene copolymer having a Mooney viscosity of 20-100 at 100 deg.C and a propylene content of 20-50% and (D) an inorganic filler at specific ratios.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a propylene homopolymer composition that has excellent adhesion to polyurethane even without the use of a primer. More specifically, (A) (1) propylene homopolymer and ethylene-propylene copolymer rubber, (2) an organic compound having at least one unsaturated bond in the molecule and containing a hydroxyl group, and (3) organic A modified propylene polymer obtained by treating with a peroxide, (B) a crystalline ethylene-propylene block copolymer, and (C) an amorphous ethylene-propylene copolymer having a Mooney viscosity of 20 to 100, and (D) a propylene-based polymer composition consisting of an inorganic filler, which not only has excellent mechanical properties such as rigidity and low-temperature impact resistance, but also has good adhesion to polyurethane without using a primer. The object of the present invention is to provide a propylene polymer composition with good properties.

As is well known, propylene polymers (propylene homopolymer, propylene copolymer) not only have excellent moldability, but also have excellent mechanical properties, heat resistance, solvent resistance, oil resistance, and Because of its good properties such as chemical resistance, it is widely manufactured industrially and used in a wide variety of fields as parts of automobiles, electrical appliances, electronic equipment, and other daily necessities. However, since it does not have a polar group in its molecule (so-called non-polar), it does not have good adhesion to polyurethane, which causes various problems. In this regard, a widely used automobile bumper will be explained as an example.

Conventionally, bumpers made of metal or polyurethane have been widely used. In recent years, with the aim of reducing the weight and cost of automobiles, propylene polymers (propylene homopolymer, ethylene-propylene random or block copolymers) containing propylene as the main component or compositions containing propylene polymers as the main component have been developed. Bumpers made from objects are widely used. When this bumper is installed on a vehicle, the surface of the molded product is textured in advance, and in many cases it is used without painting. In many cases, they are coated with polyurethane paint and installed on vehicles, and this proportion is increasing as cars become more luxurious.

However, as mentioned above, propylene-based polymers are chemically extremely inert polymeric substances because they do not have polar groups in their molecules. Therefore, when painting polyurethane, the molded product is generally subjected to electrical treatment beforehand. Surface treatment methods such as surface treatment methods (eg, corona discharge treatment methods, plasma treatment methods), mechanical roughening methods, flame treatment methods, and oxygen or ozone treatment methods are well known.

Furthermore, prior to these surface treatments, it is recommended that the surface be cleaned with a solvent such as alcohol or aromatic hydrocarbon. Additionally, methods are known in which molded articles are immersed in organic solvents such as tricrene, perchlorethylene, pentachlorethylene, and toluene at temperatures close to their boiling points or exposed to solvent vapors [e.g., Magnetic Takagi, Heizo Sasaki Edited by ``Plastic Materials Course■''
Polypropylene Resin, pp. 218-219, published by Nikkan Kogyo Shimbun, 1962] However, all of these methods not only require processing equipment, but also It takes a considerable amount of time.

Furthermore, in reality, the molded product (bumper) is undercoated with a primer that can adhere to a propylene polymer, and then a polyurethane paint is applied as a topcoat. In other words, brimer undercoating → baking → polyurethane painting → baking (
It is necessary to go through a process of 2 coats, 2 bakes or 3 coats, 2 bakes, and this painting process requires a long time (usually about 1 hour and 30 minutes). For this reason, manufacturing bumpers coated with polyurethane requires a long painting cycle, which not only makes mass production difficult but also increases costs.

When manufacturing other automobile parts, electrical appliance parts, electronic appliance parts, etc., when propylene-based polymers are used and polyurethane is coated, the same problems as above occur, although the coating methods are different.

In order to solve these problems, some of the present inventors have developed a modified propylene-based polymer obtained by treating a propylene copolymer with an organic compound containing a hydroxyl group and an organic peroxide.

! We have previously proposed a propylene polymer composition consisting of an ethylene-propylene block copolymer, an amorphous ethylene-propylene copolymer, and an inorganic filler (Japanese Patent Application No. 113279/1982). The composition not only has excellent adhesion to polyurethane, but also has good flexural modulus (rigidity) and impact resistance at low temperatures, as well as excellent processability and moldability. The gloss of molded articles (for example, bumpers) of the composition is not sufficient compared to conventional propylene polymer compositions, and the appearance is inferior. This tendency becomes even more pronounced when pre-treatment for painting (for example, steam treatment with 1,1.1-trichloroethane) is carried out. Also,
Attempting to further improve the adhesion with polyurethane by increasing the blending ratio of the modified propylene polymer used results in problems such as a decrease in gloss and an increase in the occurrence of flow marks. There are problems in that the use may be restricted unless the molded product is a matte type that does not require gloss or a molded product that has a fully painted finish.

From the above, the present invention does not have these problems (defects), that is, it maintains various mechanical properties (for example, impact strength, rigidity) that propylene polymers have. Another object of the present invention is to obtain a propylene polymer composition that not only improves moldability but also has good moldability and appearance, and also has excellent adhesion to polyurethane without using a primer.

According to the present invention, the above-mentioned problems are solved by (A) (1) Propylene homopolymer and ethylene-propylene copolymer rubber containing 100 parts by weight of (2) "at least one impurity in the molecule." 0.1 to 50 parts by weight of an organic compound having a saturated bond and containing a hydroxyl group (hereinafter referred to as a hydroxyl compound) and (3) 0.01 to 20 parts by weight of an organic peroxide. Modified propylene polymer obtained by CB) melt flow index (JIS K-
7210 at a temperature of 230°C and a load of 2.1
Measured under eKg conditions, hereinafter referred to as rMFRJ) is 2.0
A crystalline ethylene-propylene block copolymer with an ethylene content of 2.0 to 15% by weight, (C) a Mooney viscosity (ML, (100°C)) of 201+4 to 10 ( l, and the propylene content is 20 to 5
0% by weight] and (D) an inorganic filler, the composition ratio of the inorganic filler in the composition is 2.0 to 25% by weight, The ratio of the hydroxyl compound to 100 parts by weight of the total amount of the modified propylene polymer, crystalline ethylene-propylene block copolymer, and amorphous ethylene-propylene copolymer is 0.01 to 10.0 parts by weight as one unit. %, and the composition ratio of the modified propylene polymer in the total amount of the modified propylene polymer and the crystalline ethylene-propylene block copolymer is 5 to 90% by weight, and the modified propylene polymer in the composition is The composition ratio of the based polymer is at least 5.0% by weight, and the composition ratio of the amorphous ethylene-propylene copolymer is 15 to 40% by weight. The proportion of the engineered ethylene-propylene copolymer rubber in the ethylene-propylene copolymer rubber is 1 to 40% by weight,
The propylene content of the copolymer rubber is 20 to 50% by weight.
, and Mooney viscosity (ML, (100°C
)) is 10 to 50. Pro1+4 pyrene polymer composition.

It can be solved by The present invention will be explained in detail below.

(A) Modified propylene polymer The modified propylene polymer of the present invention is obtained by treating the propylene homopolymer and ethylene-propylene copolymer rubber described below with a hydroxyl compound and an organic peracid compound. , and its manufacturing method is described in detail in the specification of JP-A-58-154732.

(1) Propylene homopolymer The MFR of this propylene homopolymer is usually 0.01-1 from the viewpoint of moldability and mechanical properties of the resulting composition.
00 g/710 minutes, preferably 0.01 to 50 g/l, 0 minutes, particularly preferably 0.02 to 20 g/10 minutes.

(2) Ethylene-propylene copolymer rubber L1 The ethylene-propylene copolymer rubber used to produce the modified propylene polymer of the present invention has ethylene and propylene as main components. This ethylene-propylene copolymer rubber includes a copolymer rubber obtained by copolymerizing ethylene and propylene, and ethylene and propylene as main components, 1,4-pentadiene, 1,5-hexadiene, and 3, linear or branched diolefins containing two double bonds at the ends, such as 3-dimethyl-1,5-hexadiene;
! , 4-hexadiene and 6-methyl-1,5-hebutadiene, or bicyclo(2,2,1)-hebutene-2
A multicomponent copolymer obtained by copolymerizing 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) and its derivatives (for example, ethylidene norbornene). In the case of copolymer rubber of 0 or more, which is broadly classified as rubber, and in the case of multi-component copolymer rubber, the propylene content is 20 to 5.
It is 0% by weight. In addition, Mooney viscosity (ML, (
100°C)] is 10 to 50, preferably 10 to 1+440, particularly preferably 15 to 40. When an ethylene-propylene copolymer rubber having a Mooney viscosity of less than 10 is used, moldability is good, but adhesion strength with the urethane paint described later is not sufficiently improved.

On the other hand, if it exceeds 50, flow marks will occur on the surface of the molded product, which is unfavorable in terms of appearance.

In producing the modified propylene polymer of the present invention,
iii the propylene homopolymer and the ethylene-
The proportion of ethylene-propylene copolymer rubber in the total amount of propylene copolymer rubber is 1 to 40% by weight, and 2
-40% by weight is desirable, especially 5-35% by weight. If the proportion of ethylene-propylene copolymer rubber in the total amount of propylene homopolymer and ethylene-propylene copolymer rubber is less than 1% by weight, even if modified (treated) as described below, the adhesion strength with the paint film will be poor. On the other hand, if it exceeds 35% by weight, the adhesion strength with =S is good, but not only flow marks are generated on the surface of the molded product, but also the gloss is reduced.

(3) Hydroxyl compound Furthermore, a hydroxyl compound is a compound having at least one unsaturated bond (double bond, triple bond) and containing a hydroxyl group. Typical examples include alcohols with double bonds, alcohols with triple bonds, esters of -valent or divalent unsaturated carboxylic acids and unsubstituted dihydric alcohols, and unsaturated carboxylic acids and unsubstituted trihydric alcohols. Examples include esters with alcohols, esters with unsubstituted tetrahydric alcohols, and esters with unsubstituted trihydric or higher alcohols.

(4) Organic peroxide Furthermore, organic peroxides are generally used as initiators in radical polymerization and crosslinking agents for polymers, and those with a half-life of 1 minute of 100°C or more are preferable.
Particularly preferred is a temperature of 130°C or higher. If the temperature is below 100° C., it is not only difficult to handle, but also the effect of using it is not very noticeable, which is not desirable.

(5) Mixing ratio In producing the mixture of the present invention, the total amount of propylene homopolymer and ethylene-propylene copolymer rubber is 1
The mixing ratio of the hydroxyl compound to 0.00 parts by weight is 0.1 to 50 parts by weight, preferably 0.2 to 30 parts by weight, and particularly preferably 0.3 to 20 parts by weight. If the mixing ratio of the hydroxyl compound to 100 parts by weight of the total i of the propylene homopolymer and ethylene-propylene copolymer rubber is less than 091 parts by weight, the effect of improving adhesion is insufficient. On the other hand, even if 50 parts by weight or more is used, the effect of improving adhesion depending on the amount used is not observed, and is rather unfavorable because the original properties of the propylene homopolymer are impaired.

Further, the mixing ratio of the organic peroxide is 0.01 to 20 parts by weight with respect to 100 parts by weight of the total amount of propylene homopolymer and ethylene-propylene copolymer rubber, and 0.05 parts by weight.
~IO parts by weight are desirable, and 0.1 to 7 parts by weight are particularly preferred. If the mixing ratio of organic peroxide to 100 parts by weight of the total amount of propylene homopolymer and ethylene-propylene copolymer rubber is less than 0.01 parts by weight, not only will the effect of improving adhesion be low, but also the adhesion strength of the mixture will decrease. Durability also decreases. On the other hand, if the amount is more than 20 parts by weight, the excellent mechanical properties of the polymer will deteriorate, which is undesirable in any case.

(6) Method for producing modified propylene polymers To produce the modified propylene polymers of the present invention, one or more propylene homopolymers, ethylene-propylene copolymer rubber, hydroxyl compounds, and organic peroxides are added to the It can be manufactured by processing (heating) at a mixing ratio. At this time, the propylene homopolymer, ethylene-propylene copolymer rubber, hydroxyl compound, and organic peroxide may be mixed together during the treatment, but these may be mixed in advance in a triblend, or at a relatively low temperature (hydroxyl Knead at a temperature at which the system compounds do not react,
It is obtained by heating the resulting mixture as described below.

If the treatment is carried out at high temperatures, either the propylene homopolymer or the ethylene-propylene copolymer rubber may deteriorate. However, the graft polymerization must be carried out at a temperature at which the organic peroxide used to graft polymerize the propylene homopolymer, ethylene-propylene copolymer rubber, and hydroxyl compound decomposes.
From the above, this treatment is generally carried out at a temperature of IEIO to 300°C (preferably 170 to 280°C), although it varies depending on the type of organic peroxide used.

The general formulas and representative examples of the hydroxyl compounds and organic peroxides, as well as mixing methods and treatment methods are described in detail in the specification of JP-A-58-154732.

(B) Crystalline ethylene-propylene block copolymer Also, the MFR of the crystalline ethylene-propylene block copolymer used in the present invention is 2.0 to too g.
71 o min, preferably 3.0 to 80 g/10 min, particularly preferably 5.0 to 50 g/10 min.

If a crystalline ethylene-propylene block copolymer with an MFR of less than 2.0 g/10 minutes is used, the resulting composition will have a low flexural modulus, and this decrease in flexural modulus can be compensated for by using other synthetic resins or fillers. If supplementary agents are used, the balance between flexural modulus and impact strength will be poor. on the other hand,
If a crystalline ethylene-propylene block copolymer with a weight exceeding 100 g/10 minutes is used, not only will it be difficult to uniformly disperse the components of the mixed wire Shisen, but the impact strength at low temperatures of the resulting composition will decrease. descend.

Furthermore, the ethylene content of the block copolymer is 2.
The amount is 0 to 15% by weight, preferably 3.0 to 15% by weight, and particularly preferably 3.0 to 12% by weight. If the ethylene content is less than 3.0% by weight, the resulting composition will have poor impact resistance at low temperatures. On the other hand, if it exceeds 15% by weight, the resulting composition will have poor mechanical properties such as rigidity (flexural modulus) and tensile strength.

The propylene homopolymer, ethylene-propylene copolymer rubber, and crystalline ethylene-propylene block copolymer used to produce the modified propylene homopolymer are all industrially produced and used in a wide variety of fields. Their manufacturing methods and various physical properties are well known.

(C) Amorphous ethylene-propylene copolymer Furthermore, the Mooney viscosity (ML, (100°C)) of the amorphous ethylene-propylene copolymer used in the present invention is from 20 to 100, preferably from 201+4 to 80. , especially 30-75.

If an amorphous ethylene-propylene copolymer with a Mooney viscosity of less than 20 is used, moldability will improve, but layer peeling may occur during gate cutting of the molded product, which may cause trouble. There is. On the other hand, 100
If a material exceeding the A molded product with good appearance without noticeable lines or the like cannot be obtained.Furthermore, the propylene content of this copolymer is generally 20 to 50% by weight.

25 to 45% by weight is desirable, especially 25 to 4% by weight.
0% by weight is preferred. This amorphous ethylene-propylene copolymer has rubber-like properties, is industrially produced and used in a wide range of fields, and its manufacturing method is also widely known.

CD) Inorganic filler The inorganic filler used in the present invention is generally one widely used in the fields of synthetic resins and rubber. These inorganic fillers include sI!, which does not react with ugliness and water! - Compounds that do not decompose during crosstalk and molding are preferably used. The inorganic fillers 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 their water. It is broadly classified into compounds such as hydrates (hydroxides), sulfates, carbonates, silicates, their double salts, and mixtures thereof. A representative example of the inorganic filler is disclosed in Japanese Patent Application No. 59-853.
It is described in the specification of No. 5. Among these inorganic fillers, those in powder form preferably have a diameter of 30 microns or less (preferably 10 microns or less), and those in fibrous form have a diameter of 1 to 500 microns (preferably 1 micron or less). ~3
00 microns) and has a length of 0.1 to 6-■ (preferably 0.1 to 5 m+*);
The flat fillers preferably have a diameter of 30 microns or less (preferably 10 microns or less). Among these inorganic fillers, flat (flake-like) fillers and powdery fillers are particularly preferred. Suitable inorganic fillers include LARC, mica, silica, and glass #lim.

Examples include graphite.

(E) Composition ratio The composition ratio of the inorganic filler in the composition obtained in the present invention is 2.0 to 25% by weight, and 2.5 to 25% by weight.
% by weight is preferred, particularly 3.0 to 20% by weight. The composition ratio of the inorganic filler in this composition is 2.
If it is less than 0% by weight, the flexural modulus of the resulting composition will not be improved, while if it exceeds 25% by weight, not only will the impact resistance of the composition at low temperatures be poor, but it will also cause the generation of silver during molding. It may become. In order to prevent the formation of silver, there is a method of pre-drying the composition, but this is not a good idea when mass producing large molded products such as bumpers.

Furthermore, the modified propylene polymer and crystalline ethylene-
Composition ratio of the modified propylene polymer in the total amount (total) with the propylene block copolymer: 5 to 90% by weight
and preferably 10 to 80% by weight, especially 20 to 80% by weight.
70% by weight is preferred. If the composition ratio of the modified propylene polymer to the total amount of the modified propylene polymer and the crystalline ethylene-propylene block copolymer is less than 5% by weight, the adhesion between the composition and the polyurethane is poor. On the other hand, if it exceeds 80% by weight, impact resistance at low temperatures will be insufficient.

Furthermore, the proportion of the modified propylene polymer in the composition is at least 5.0%.

5.0 to 40% by weight is preferable, and 5.0 to 35% by weight is particularly preferable.0 If the composition ratio of the modified propylene polymer in the composition is less than 5.0% by weight, it will be the same as the polyurethane in the composition. Adhesion is not good.

Further, the composition ratio of the amorphous ethylene-propylene copolymer in the composition is 15 to 40% by weight, and 15 to 3% by weight.
The proportion of the amorphous ethylene-propylene copolymer in the composition is preferably less than 15% by weight, preferably 5% by weight, and most preferably 18 to 35% by weight, since the impact resistance of the composition at low temperatures is poor. On the other hand, if it exceeds 40% by weight, the impact resistance at low temperatures is excellent, but the flexural modulus (rigidity) is low, and the balance between these is not good.

Further, the proportion of the organic compound containing a hydroxyl group to 100 parts by weight of the total amount of the modified propylene polymer, the crystalline ethylene-propylene block copolymer, and the amorphous ethylene-propylene copolymer is 0.0. 01-1000 parts by weight, 0.1-10.
0 parts by weight is preferred, particularly 0.2 to 5.0 parts by weight. The ratio of organic compound containing hydroxyl group to 100 parts by weight of the total amount of these polymers is 0.0.
If the amount is less than 1 part by weight, the adhesion between the resulting composition and polyurethane will be insufficient.

Further, even if the amount exceeds 1,000 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 polymer, the crystalline ethylene-propylene block copolymer, the amorphous ethylene-propylene copolymer and the inorganic filler are used. The agent may be uniformly mixed within the above composition ratio range by applying a mixing method practiced in the field of ordinary olefin polymers.
All the composition components may be mixed at the same time, or some of the composition components may be mixed in advance to produce a so-called masterbatch.
This masterbatch and the remaining composition components may be mixed. In this case, it is generally blended (added) to the olefin polymer.
Additives such as heat, oxygen or UV stabilizers, metal deterioration inhibitors, plasticizers, flame retardants, lubricants, fillers, colorants, antistatic agents and electrical property modifiers may be added to the composition. It may be added depending on the intended use of the composition as long as it does not impair the physical properties of the wood.

The composition thus obtained is usually molded into pellets, and the desired molded product is produced by a molding method such as injection molding or extrusion molding that is commonly used in the respective fields of thermoplastic resins.

Even when melt-kneading is performed when producing the above composition,
Even when molding, the temperature is higher than the melting point of the polymer used, but at a temperature that does not cause thermal decomposition. For these reasons, the temperature is generally 180 to 300°C (preferably 190 to 300°C).
250°C).

Generally, olefin polymers have extremely poor adhesion with polyurethane, so when applying polyurethane paint to molded products of olefin polymers or their compositions, it is necessary to first apply and dry a primer and then apply the polyurethane paint. However, the propylene polymer composition of the present invention has excellent adhesion to polyurethane.

Polyurethane can be applied directly to the surface of a molded product without applying a primer to the surface of the molded product (using a primer further improves adhesion).

Further, the flexural modulus is 9.000 Kg/crn' or more, and the Izot impact strength (notched) at -30°C is 8 Kg a cm/cs. Furthermore, the melt flow index is 5 g/10 minutes or more.

- The present invention will be explained in more detail below with reference to Examples.

In addition, in the examples and comparative examples, the flexural modulus is AS
TM 0790, Izot impact strength was measured according to ASTM 025B, gloss was measured according to JIS 28741, and flow marks were measured using the following flat plate test piece (film gate, gate thickness 0.3 mm). Judgment was made based on the presence or absence of occurrence. In addition, the coating film adhesion strength was measured using a flat plate test piece (thickness 2m11
．． 130X 130 m++e) was placed in the vapor of 1.1.1-) lychloroethane for 30 seconds, and after thoroughly drying, /\ urethane paint (manufactured by Nippon P Chemical Co., Ltd., trade name R257, solid) was applied to the dry thickness. The coating was applied so that the thickness was 20 to 30 microns. After leaving it for about 15 minutes,
Urethane paint (manufactured by Nippon P Chemical Co., Ltd., product name, R2S
e, Warakah top) with a dry thickness of 30 to 4
It was applied to a thickness of 0 microns and dried at 80° C. for 30 minutes. Then, keep it at constant room temperature (temperature: 23℃, humidity: 6℃).
5%) for 48 hours. The obtained coated material (test piece) was cut into 10+ss width, and after forcibly peeling off a part of the coating film (approximately 10 mm) from the resin part of the test piece, the remaining adhered part was removed using a tensile tester. The peel strength was determined by pulling the film in the opposite direction (180 degrees) at a speed of 501,111/min and measuring the peel strength. Furthermore, the second eye test was the same as above, except that a polyurethane paint (Shiraki P Chemical Co., Ltd., trade name R255, Metallic Red) was used instead of the high urethane paint used to measure the adhesion strength of the paint film. Treatments such as coating and drying were performed. Mark the coated surface of the obtained test piece with 1+u+ spacing.
I placed cellophane tape in 00 pieces and completely adhered it using finger pressure. This cellophane tape was suddenly peeled off at an angle of 45 degrees. This operation was repeated twice to determine the percentage of the remaining coating film. In addition, the tensile test is based on JIS
Measured according to K-8301.

Furthermore, the gasoline resistance was determined by immersing the specimen at room temperature (20° C.) for 24 hours, and then observing the state of change in the specimen.

In addition, the modified propylene polymer, modified propylene homopolymer, modified propylene copolymer, ethylene-propylene block copolymer,
Amorphous ethylene-propylene copolymer rubber, inorganic filler,
The physical properties, manufacturing method, etc. of other composition components are shown below.

[(A) Modified propylene polymer]

As a modified propylene homopolymer, MFR is 0.5g7
Propylene homopolymer and Mooney viscosity [M
Amorphous ethylene 1+4-propylene copolymer rubber with L1+4, 100°C) of 20 was used in the proportions shown in Table 1, and the total amount of these was 10013 parts by weight.
4.0 parts by weight of 2-hydroxyethyl acrylate and 1.0 parts by weight of 2.2'-bis(tert-butylperoxyisopropyl)benzene were pre-triblended for 5 minutes using a Henschel mixer.

The obtained mixture was kneaded using a vented extruder (diameter: 40°C threshold, cylinder temperature: IEO to 200'O) to produce pellets, which were then used.

Table 1 [(B) Modified propylene homopolymer] For comparison, as a modified propylene homopolymer, 4.0 parts by weight of 2 was added to 1 part of 100i of the above propylene homopolymer.
-Produce pellets by triblending and kneading hydroxyethyl acrylate and 0.4 parts by weight of 2.2'-bis(tertiary-butylperoxyisopropyl)benzene in the same manner as in the production of modified propylene polymers. [hereinafter referred to as "modified PP (B) J]" was used.

[(C) Modified propylene copolymer]

For comparison, as a modified propylene copolymer, MFR
Ethylene-propylene block copolymer (ethylene content 8.0% by weight) 100 with a weight of 0.05 g/10 min
4.0 parts by weight of 2-hydroxyethyl acrylate and 1.0 parts by weight of 2.2°-bis(tertiary-
Butylperoxyisopropyl)benzene was pre-triblended for 5 minutes using a Henschel mixer. The obtained mixture was extruded through a vent (diameter 4hm)
, cylinder temperature 1f30~200°C) to produce pellets while kneading [hereinafter referred to as "modified PP (C
) J) was used.

[(D) Ethylene-propylene block copolymer] As an ethylene-propylene block copolymer, an ethylene-propylene block copolymer having an MFR of 30 g 710 minutes [ethylene content 7.5% by weight, hereinafter referred to as rP]
P (1), MFR 28 g / 1
Ethylene-propylene block copolymer [ethylene content 10.1% by weight, hereinafter rPP (2) J]
], an ethylene-propylene block copolymer with an MFR of 15 g/10 min [ethylene content 8
．． 8 mold breaking%, hereinafter referred to as rPP(3) J], MF
An ethylene-propylene block copolymer (ethylene content: 6.0% by weight, hereinafter referred to as "PP(4)") having R of 12 g/10 minutes was used.

[(E) Amorphous ethylene-propylene copolymer] As an amorphous ethylene-propylene copolymer, the Mooney viscosity (ML, (100"0)) is 35 te 1+
An amorphous ethylene-propylene copolymer (propylene content: 27% by weight, hereinafter referred to as rEPRJ) was used.

[(F) Inorganic filler]

As inorganic fillers, talc with an average particle size of 2.0 microns, calcium carbonate (hereinafter referred to as rcacO3J) with an average particle size of 2.0 microns, and wollastonite with an average particle size of 7 microns were used. .

Examples 1 to 8, Comparative Examples 1 to 7 Modified propylene homopolymers, modified propylene copolymers, and ethylene-propylene block copolymers (as PP resins) whose blending amounts are shown in Table 2, The amorphous ethylene-propylene copolymer and talc, wollastonite and CaCO3 (as inorganic fillers) were mixed for 5 minutes using a supermixer. Each of the obtained mixtures was passed through a vented twin-screw extruder (cylinder temperature 180~
A pellet (composition) was produced while kneading using a 200° C. diameter 30 mm. Each pellet was molded into a 5 oz. plate (thickness 2a+a+, 13
0x130 mm), specimens for measuring flexural modulus and specimens for measuring Izod impact strength were manufactured. The coating film adhesion strength, Izot impact strength (measurement temperature -30°C 1-40°C), bending property and gloss (
gloss), flow mark determination, cross-cut test, and gasoline resistance test. The results are shown in Table 3.

(Left below) In addition, gasoline resistance tests were conducted on all samples of Example and Comparative N, but no abnormalities such as peeling, blistering, wrinkles, etc. could be observed on the surface of any of the specimens. .

From the results of the above Examples and Comparative Examples, the propylene homopolymer composition obtained by the present invention is
The composition introduced in No. 113279 not only has excellent mechanical strength (flexural modulus, impact resistance at low temperatures), but also has good processability, as well as excellent adhesion to polyurethane and gasoline resistance. It is clear that the molded product has excellent surface appearance (gloss) while almost satisfying these requirements.

The propylene homopolymer composition obtained by the present invention exhibits the following effects compared to the composition introduced in Japanese Patent Application No. 80-113279.

(1) Workability and moldability are the same or better.

(2) The molded product has excellent appearance (gloss).

(3) No flow marks occur on the surface of the molded product of the composition.

This means that the composition can be used not only for full-face painted products, but also for partially painted products, which are currently being used for polypropylene-only M1TR, object bumpers, etc. This is a major effect (feature).

The propylene homopolymer composition of the present invention can be used in a wide variety of ways to achieve the above effects. Typical examples include automobile parts such as bumpers, bumper corners, and engine undercovers.

Claims (1)

Scope of Claims: (A) 100 parts by weight of (1) propylene homopolymer and ethylene-propylene copolymer rubber, and (2) an organic compound having at least one unsaturated bond in the molecule and containing a hydroxyl group. A modified propylene polymer obtained by treating 0.1 to 50 parts by weight of a compound and (3) 0.01 to 20 parts by weight of an organic peroxide, (B) having a melt flow index of 2.0 to 100 g/
10 minutes, and a crystalline ethylene-propylene block copolymer having an ethylene content of 2.0 to 15% by weight, (C) Mooney viscosity [ML_1_+_4, (100°C)
] is 20 to 100, and the propylene content is 2
It is a composition consisting of an amorphous ethylene-propylene copolymer which is 0 to 50% by weight and (D) an inorganic filler, and the composition ratio of the inorganic filler in the composition is 2.0 to 25% by weight. The ratio of the organic compound containing a hydroxyl group to 100 parts by weight of the total amount of the modified propylene polymer, crystalline ethylene-propylene block copolymer and amorphous ethylene-propylene copolymer is 0.01 to 10 as a monomer unit. 0 parts by weight, and the composition ratio of the modified propylene polymer in the total amount of the modified propylene polymer and the crystalline ethylene-propylene block copolymer is 5 to 90 weight %, and The composition ratio of the modified propylene polymer is at least 5.0% by weight, and the composition ratio of the amorphous ethylene-propylene copolymer is 15 to 40% by weight, and the proportion of propylene homopolymer in the modified propylene polymer is at least 5.0% by weight. The proportion of ethylene-propylene copolymer rubber in the combined and ethylene-propylene copolymer rubber is 1 to 40% by weight, and the propylene content of the copolymer rubber is 20% by weight.
~50% by weight, and Mooney viscosity [ML_l_+
_4, (100°C)] is 10 to 50. A propylene polymer composition.