JPS62257945A - Propylene polymer composition - Google Patents

Abstract

PURPOSE:The titled composition suitable as bumpers of automobiles, etc., having improved mechanical properties such as rigidity, etc., improved adhesivity to polyurethane without requiring primer, obtained by blending a specific modified propylene polymer with a propylene polymer, etc., in a specific ratio. CONSTITUTION:(A) 5wt% modified polymer obtained by treating A1: 100pts.wt. propylene polymer or blend of propylene homopolymer and ethylene-propylene copolymer rubber with A2: 0.1-5pts.wt. organic compound containing one or more unsaturated bonds and hyroxyl group in the molecule and A3: 0.01-20pts. wt. organic peroxide is blended with (B) propylene polymer (the ratio of the component A to the components A+B is 5-90wt%), (C) 1-35wt% amorphous ethylene-propylene copolymer having 20-100 Mooney viscosity and and 20-50% propylene content and (D) 3-25wt% high-density ethylenic polymer having >=0.935g/cm<2> density.

Description

DETAILED DESCRIPTION OF THE INVENTION ff, -1-15 The present invention relates to a propylene-based polymer composite assembly that has excellent adhesion to polyurethane even without the use of a primer.

For more details, see (A) (+) propylene polymer.
(2) an organic compound having at least one unsaturated bond in the molecule and containing a hydroxyl group; (3) a modified propylene-based polymer obtained by treating with an organic peroxide; (B) a propylene-based polymer; The present invention relates to a propylene polymer composition consisting of a polymer, (C) an amorphous ethylene-propylene copolymer having a Mooney viscosity of 20 to 100, and (D) a high-density ethylene polymer, and has high rigidity and low-temperature impact resistance. Propylene-based polymers not only have excellent mechanical properties such as elasticity, but also have good layerability with polyurethane without using pliers, have excellent weather resistance, and have a good appearance. The object is to provide a combined composition.

As is well known, cross-linked propylene polymers (propylene homopolymer, propylene copolymer) not only have excellent moldability, but also have excellent mechanical properties, heat resistance, solvent resistance, oiliness, and Because it has good properties such as chemical resistance, it is widely manufactured industrially and is widely used in many fields as industrial parts such as automobiles, electrical appliances, and electronic appliances, and as daily necessities. However, since it does not have a polar group in the molecule (so-called non-polar), V: layer properties with polyurethane are not good.
Therefore, there are 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-based polymers containing propylene as the main component (propylene single type monomer, ethylene-propylene random or block copolymer) or propylene-based polymers as the main component have been developed. Bumpers made from compositions 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 rapidly increasing as automobiles 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. Methods (eg, corona discharge treatment, plasma treatment) 1 Surface treatment methods such as mechanical heavy phase surface treatment, flame treatment, and oxygen or ozone treatment 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. moreover.

It is also known to immerse the molded article in organic solvents such as trichlorethylene, perchlorethylene, pentachlorethylene, and toluene at temperatures close to the temperature point or to expose the molded article to solvent vapors (see, for example, Yoshiyuki Takagi and Heizo Sasaki). Edit, °“
However, all of these methods require equipment for processing. However, it takes a considerable amount of time to process them.

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. That is, primer undercoat → baking → polyurethane coating → 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, tricycle parts, electrical equipment parts, electronic equipment parts, etc., when propylene-based polymers are used and polyurethane 9215 is applied, the same problems as the above two occur, although the application method is different. There is.

Generally, polypropylene or its compositions used for bumpers and the like are added with UV absorbers, UV stabilizers, antioxidants, etc. in any combination in order to enhance weather resistance. However, after several years of use in actual vehicles, the surface of the molded product becomes discolored, chalked, or cracked, and the current state of the art is inadequate. moreover,
The demand for bumper grades with good weather resistance is becoming stronger as automobiles become more luxurious and are increasingly used in regions with harsh climates.

Therefore, as a countermeasure, it may be possible to increase the amount of the conventional weather-resistant formulation or add new additives, but simply increasing or adding these may cause problems with appearance during molding (for example, surface gloss unevenness or whitening). There are various problems such as bleed of increased or added additives to the surface of the molded product after molding, deteriorating the appearance, and whitening of the surface of the molded product after long-term use in actual vehicles.

In addition, in the field of industrial parts and daily necessities, it not only has the excellent mechanical properties mentioned above, but also has good adhesion to polyurethane without using a brimer, and has excellent weather resistance. 41 products are desired as propylene polymers with good appearance properties.

From the above, the present invention does not have these problems (defects), that is, the present invention does not have the various mechanical properties (for example, impact strength, rigidity) that propylene polymers have. It not only maintains or improves the properties of polyurethane, but also has good moldability and weather resistance, and at the same time, it can adhere well to polyurethane without using a primer, and also has good appearance (especially gloss). The object of the present invention is to obtain a propylene polymer composition having good properties.

According to the present invention, the above problems are solved by (A) (1) a mixture of a propylene polymer or a propylene homopolymer and an ethylene-propylene copolymer rubber; (2) "Having at least one unsaturated bond in the molecule,
and hydroxyl group-containing organic compounds” (hereinafter referred to as “organic compounds containing hydroxyl groups”)
A modified propylene polymer obtained by treating 0.1 to 50 parts by weight of a hydroxyl compound (referred to as a hydroxyl compound) and 0.01 to 20 parts by weight of an organic peroxide (B) a propylene polymer; (C) Mooney viscosity (ML, (100°C)) is 201+4 to 100, and the propylene content is 20 to 50
% by weight of an amorphous ethylene-propylene copolymer and (D) a high-density ethylene-based polymer having a density of 0.935 g/cm'' or more; The composition ratio of the polymer is 3.0 to 25% by weight, and the ratio of the hydroxyl compound to the total of the modified propylene polymer, propylene polymer, and amorphous ethylene-propylene copolymer is 1 to 100 parts by weight. It is 0.01 to 10.0 parts by weight as one monomer unit, and the composition ratio of the modified propylene polymer in the total amount of the modified propylene polymer and the propylene polymer is 5 to 90% by weight, The composition ratio of the modified propylene polymer in the composition is at least 3.0% by weight, and the composition ratio of the amorphous ethylene-propylene copolymer is 1.0 to 3%.
This problem can be solved by a propylene-based polymer composition having a content of 5% by weight. The present invention will be explained in detail below.

(A) Modified propylene polymer The modified propylene polymer of the present invention is a mixture of a propylene polymer or a propylene homopolymer and an ethylene-propylene copolymer rubber described later, and a hydroxyl compound and It is obtained by treating an acid compound, and its manufacturing method is described in JP-A-58
It is described in detail in the specification of Japanese Patent No.-154732.

(1) Propylene polymer The propylene polymer used to produce the modified propylene polymer of the present invention is a propylene homopolymer, a block copolymer containing propylene as a main component and ethylene and/or an α-olefin. Copolymers and random copolymers with ethylene and/or α-olefins based on propylene. In both block copolymers and random copolymers, the copolymerization ratio of ethylene and α-olefin is at most 2 as the total amount.
0% by weight (preferably 15'g1i% or less),
Further, the α-olefin has 4 to 12 carbon atoms. The α
Representative examples of -olefins include butene-1, hexene-1,4-methylhexene-1 and octene-1.

These propylene polymers are industrially produced and used in a wide variety of fields. Furthermore, the physical properties and manufacturing methods of these propylene polymers are well known.

Moreover, instead of the propylene polymer, a mixture of a propylene homopolymer and an ethylene-propylene copolymer rubber described later in the composition ratio described later can also be used. In this case, the ethylene-propylene copolymer rubber used has ethylene and propylene as main components. Examples of this ethylene-propylene copolymer rubber include the amorphous ethylene-propylene copolymer described later. The content of propylene is 20 to 50% by weight in both the copolymer rubber described below and the multicomponent copolymer rubber. In addition, the Mooney viscosity (ML, (100°C)) l+4 is !θ~50, preferably 10-40, particularly 15
-40 is suitable. When an ethylene-propylene copolymer rubber with a Mooney viscosity of less than 10 is used, the moldability is good, but the adhesion strength with the urethane paint described later is not sufficiently improved.On the other hand, when one with a Mooney viscosity of more than 50 is used, Flow marks 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,
The proportion of the ethylene-propylene copolymer rubber in the total amount of the propylene homopolymer and the ethylene-propylene copolymer rubber is usually at most 40% by weight, preferably 1 to 40% by weight, especially 2% by weight. ~35g
X1% is suitable. If the proportion of ethylene-propylene copolymer rubber in the total amount of propylene homopolymer and ethylene-propylene copolymer rubber exceeds 40% by weight, the adhesion strength with the coating film is good, but the molded Not only will flow marks occur on the surface, but the gloss will be reduced.

The melt flow rate of this propylene polymer (JIS
Measured under condition 14 according to K7210, below r
MFR (2) J) is usually 0.01 to 100 from the viewpoint of moldability, mechanical properties of the composition, etc.
g710 minutes, preferably 0.01 to 80 g/10 minutes, particularly preferably 0.02 to 60 g/10 minutes.

(2) 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.

(3) Organic peroxides In addition, 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 Preferably,
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.

(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. Particularly suitable is 0.3 to 20 parts by weight. If the mixing ratio of the hydroxyl compound to 100 parts by weight of the propylene polymer is 0.1 part by weight or less, 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 rather the original properties of the propylene homopolymer are impaired, which is not preferable.

The mixing ratio of the organic peroxide to 100 parts by weight of the propylene polymer is 0.01 to 20 parts by weight, and 0.01 to 20 parts by weight.
05 to IO parts by weight are desirable, particularly 0.1 to 7 parts by weight. If the mixing ratio of the organic peroxide to 100 parts by weight of the propylene polymer is 0.01 parts by weight or less, not only the effect of improving adhesion is low, but also the durability of the adhesion strength of the mixture is reduced. On the other hand, at 20 parts by weight or more,
In either case, this is undesirable because the originally good mechanical properties of the polymer are reduced.

(5) Method for producing modified propylene polymer To produce the modified propylene polymer of the present invention, one or more propylene polymers, hydroxyl compounds, and organic peroxides are treated (heated) at the above mixing ratio. It can be manufactured by At this time, the propylene polymer, hydroxyl compound, and organic peroxide may be mixed together during the treatment, but they must be mixed in advance in a triblend, or at a relatively low temperature (temperature at which the hydroxyl compound does not react). Knead with.

It is obtained by heating the resulting mixture as described below.

If the treatment is carried out at high temperatures, the propylene-based polymer may deteriorate. However, the graft polymerization between the propylene polymer and the hydroxyl compound must be carried out at a temperature at which the organic peroxide decomposes. Although this process differs depending on the type of
It is carried out at ~300°C (preferably 170-280°C).

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) Propylene polymer Also, the propylene polymer used in the composition of the present invention together with this modified propylene polymer is the propylene polymer used in producing the modified propylene polymer, except for MFR (2). It is the same type as the polymer (however, it does not have to be the same as that used in producing the modified propylene polymer). Among these propylene polymers, block copolymers and random copolymers are preferably used.

The MFR (2) of this propylene polymer is usually 1. Q~
100g710min, 1.0~80g/
10 minutes is preferable, especially 2.0-80 g/1
0 minutes is preferred.

If a propylene polymer having an MFR (2) of less than 1.0 g/10 minutes is used, not only will the crosstalk with the modified propylene polymer be poor, but also the moldability of the resulting composition will be poor. On the other hand, if a propylene-based polymer exceeding 100 g/710 minutes is used, the resulting composition will have poor mechanical strength.

(C) fi-shaped ethylene-propylene copolymer Mooney viscosity (ML, (100°C) of the amorphous ethylene-propylene copolymer used in the present invention)
] is 20 to 100, preferably 201+4 to 80, and particularly preferably 30 to 75.

If an amorphous ethylene-propylene copolymer with a Mooney viscosity of less than 20 is used, moldability will improve, but layer separation may occur during gate carting of the molded product, which may cause trouble. There is. On the other hand, if it exceeds 100, it will not only be difficult to uniformly disperse it with other composition components during kneading, but even if a uniform Mt oxide is obtained, there will be flow marks on the surface of the molded product. In addition, the propylene content of this copolymer is generally 20 to 50% by weight, and 25 to 4% by weight.
5 weight taro is preferable, and 25 to 40 weight 6 weight is particularly 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.

The amorphous ethylene-propylene copolymer mainly contains a copolymer rubber obtained by copolymerizing ethylene and propylene, and ethylene and propylene as main components.
1.4-linear or branched diolefins containing two double bonds at their ends, such as 1.4-pentadiene, 1.5-hexadiene and 3.3-dimethyl-1,5-hexadiene; 1.4 -terminal linear or branched diolefins such as hexadiene and 6-methyl-1,5-hebutadiene or bicyclo(2,2,1)
-Hair'tear-2 (norbornene) and its derivatives (e.g. ethylidene norbornene).
In general, it is broadly classified into multicomponent copolymer rubbers obtained by copolymerizing (generally, 10% by weight or less).

(D) High-density ethylene polymer The high-density ethylene polymer used in the present invention is an ethylene polymer with a density of 0.935 g/cm' or more, and 0.935 g/cm '
to 0.980 g/cm” is preferable,
In particular, 0.935 to 0.975 g/cm" is preferable. The ethylene polymer is generally a homopolymer of ethylene or a combination of ethylene and α-olefin (the number of carbon atoms is generally 3 to 12, Suitable α-olefins include propylene, butene-1, hexene-1,4-methylpentene-1
and octene-1.

The melt flow index (according to JIS K-7210, conditions are 4 and fl11 constant, hereinafter referred to as rMFR(1) J) of this high-density ethylene polymer is generally 0.5 to 10.0 g710 minutes. and 0.5~
80g/10min is preferable, especially 1.0~f
30g/10 minutes is suitable. MFR(1)
If a high-density ethylene polymer having a hardness of less than 0.5 g/10 minutes is used, it will not only be difficult to uniformly disperse it during kneading, but also cause flow marks to occur on the surface of the resulting molded product. On the other hand, when using an ethylene polymer that exceeds 100 g and 710 minutes, it is still difficult to uniformly disperse it during kneading, and yet it is difficult to obtain it evenly.
1IIt thing 1? IFJ impact resistance is poor.

(E) Composition ratio The composition ratio of the high density ethylene polymer in the composition obtained in the present invention is 3.0 to 35% by weight,
3.0 to 20% is preferable, and 5.0 to 20% is suitable. If the composition ratio of the high density ethylene polymer in the resulting composition is less than 3.0% by weight.

Not only is the effect of improving the impact resistance of the obtained composition poor, but also the appearance of the molded product is not good (in particular, the gloss is not satisfactory).On the other hand, if it exceeds 25% by weight, the resulting composition The heat resistance is not satisfactory.

In addition, the composition ratio of the modified propylene polymer in the total amount (total) of the modified propylene polymer and the propylene polymer is 5 to 90% by weight, and 10 to 80% by weight (
4% is desirable, and 20 to 60% by weight is particularly preferred. When the Ml ratio of the modified propylene polymer to the total amount of the modified propylene polymer and the propylene polymer is less than 5% by weight, the adhesion between the composition and the polyurethane is poor.

On the other hand, if it exceeds 90% by weight, impact resistance at low temperatures will be insufficient.

Furthermore, the composition ratio of the modified propylene polymer in one composition is at least 5% by weight, and 5 to 20% by weight.
If the proportion of the modified propylene polymer in the composition is less than 5% by weight, the adhesion between the composition and the polyurethane is poor.

Further, the composition ratio of the amorphous ethylene-propylene copolymer in the composition is 1.0 to 35% by weight; 2.
If the composition ratio of the amorphous ethylene-propylene copolymer in the composition is less than 1.0% by weight, it is preferably 0 to 35% by weight, and most preferably 3.0 to 35% by weight.
The impact resistance of the composition at low temperatures is poor, while 35
If it exceeds % 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.

Furthermore, the total amount of modified propylene polymer, propylene polymer, and amorphous ethylene-propylene copolymer is 1
The ratio of the organic compound containing a hydroxyl group to 0.00 parts by weight is 0.00 parts by weight as one monomer unit. O1~to, o1f
i parts, preferably 0.1 to 1010 parts by weight, particularly preferably 0.2 to 5.0 parts by weight.

If the proportion of the organic compound containing a hydroxyl group is less than 0.01 part by weight with respect to the total ff1100 parts by weight of these polymers, the adhesion between the resulting composition and the polyurethane will be insufficient. Moreover, even if it 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 polymer, propylene polymer, amorphous ethylene-propylene copolymer, and high-density ethylene polymer are used. It is sufficient to mix uniformly by applying a mixing method practiced in the field of ordinary olefin polymers so that the composition ratio is within the above range.At this time, all the composition components are mixed at the same time. Alternatively, a part of the composition components may be mixed in advance to produce a so-called master patch, and this masterbatch and the remaining composition components may be mixed.
Stabilizers against heat, oxygen or ultraviolet rays, metal deterioration inhibitors, which are generally blended (added) to olefin polymers,
Depending on the intended use of the composition, additives such as plasticizers, flame retardants, lubricants, fillers, colorants, antistatic agents, and electrical property improvers may be added to the extent that the physical properties of the composition are not impaired. It may also be blended.

The composition obtained in this way is usually molded into pellets, and the desired molded product is manufactured by injection molding, extrusion molding, or other molding methods 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, since the propylene polymer of the present invention has excellent adhesion to polyurethane,
Polyurethane can be applied directly to the surface of a molded product without applying a brimer to the surface of the molded product (using a brimer further improves adhesion).

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
The Izot impact strength was determined according to ASTM 025B.

In addition, the coating film adhesion strength was measured using a flat plate test piece (thickness 2III11
゜+30X 130 mm) 1.1. After placing it in l-trichloroethane vapor for 30 seconds and thoroughly drying it, apply high urethane paint (manufactured by Shiraki P Chemical Co., Ltd., trade name R2).
57, Solid) was applied to a dry thickness of 20 to 30 microns. After leaving it for about 15 minutes.

Urethane paint (manufactured by Nippon P Chemical Co., Ltd., product name.

R2Se, Waraka Top) with a dry thickness of 3
It was coated to a thickness of 0 to 40 microns and dried at 80°C for 30 minutes. Then, at constant room temperature (temperature 23°C1
It was left to stand for 48 hours in a humidity of 65%. The obtained coated material (test piece) was cut into loam width, and a part of the coating film (approximately 10 mm) was forcibly peeled off from the resin part of the test piece.
Using a tensile tester, pull the remaining adhering area in the opposite direction (180 degrees) to the coating film at a speed of 50 mm Z to determine the peel strength. It was obtained by determining I11. Furthermore, glossiness was measured on the flat test piece according to JIS K-7105. In addition, #climate test was performed using the flat plate test piece at 50%
Cut into a + m x 50 m5 pieces, irradiate them using a Sunshine Weatherometer (manufactured by Suga Test Instruments) at a black panel temperature of 83°C and rain conditions of 12 minutes and 760 minutes, take them out at each irradiation time, and observe the change in the appearance of the sample. was observed, and the results are shown below.

■ = No change 0: Slight occurrence of chalking Δ: Occurrence of cracks The physical properties and manufacturing methods of the rubber, high-density ethylene polymer, and other composition components are shown below.

[(A) Modified propylene homopolymer]

As a modified propylene homopolymer, MFR (2) is 0.
5g/10min of propylene homopolymer 85? 3.0 parts by weight of 2-hydroxyethyl methacrylate and 15 parts by weight of an amorphous ethylene-propylene copolymer having a Mooney viscosity (MLl, 100° C.) of 20
．． 7 parts by weight of 2.2'-bis(tertiary-butylperoxyisopropyl)benzene was previously triblended for 5 minutes using a Henschel mixer. The resulting mixture was kneaded using a vented extruder (diameter: 85 mm, cylinder temperature: 180 to 200°C), and a product (hereinafter referred to as modified PPJ) was used.

[(B) Ethylene-propylene block copolymer] As the ethylene-propylene block copolymer, MFR (
2) is 9.1 g/10 min of ethylene-propylene block copolymer [ethylene content 8.8% by weight, hereinafter r
PP(A) J], MFR(2) is 8.0 g
/ 10 minutes ethylene-propylene block copolymer [ethylene content 10.1% by weight, hereinafter referred to as rPP(B
) J), MFl? Ethylene-propylene block copolymer (ethylene content: 8.5% by weight, hereinafter referred to as rPP(C)J) with 100 g/10 minutes of (2)
, was used.

[(C) Propylene homopolymer]

As a propylene homopolymer, MFR (2) is 10
g/10 minutes of propylene homopolymer [hereinafter referred to as “PP (
D)” was used.

((D) Ethylene-propylene random copolymer) 1MFR (2
) is 13 g/10 min and the ethylene content is 3.
An ethylene-propylene random copolymer (hereinafter referred to as rPP(E)J) with a concentration of 1ii% was used.

[(E) Amorphous ethylene-propylene copolymer] As an amorphous ethylene-propylene copolymer.

Amorphous ethylene-propylene copolymer with a Mooney viscosity (ML, (100°C)) of 35 and 1+4 [propylene content 27% by weight, hereinafter referred to as rEPR(a)J]
and Mooney viscosity (ML, (100°C))
Amorphous ethylene-propylene copolymer in which 1◆4 is 15 [propylene content 27% by weight, hereinafter r EPR (b)
J] was used.

[(F) High-density ethylene polymer]

As a high density ethylene polymer, the density is 0.945g/
cm'' copolymer of ethylene-butene-1 (MFR
(1) 0.7 g710 min, hereinafter rH[1PE(1
) with a density of 0.960 g/c
Ethylene homopolymer (MFR(1) 20
g/IQ, hereinafter referred to as rHDPE (2)] was used.

[(G] Stabilizer) Various stabilizers include bis(2,2,8,8-tetramethyl-4-piperidine sepacate [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-ditert-butyl-4-hydroxyphenyl)propionate comethane] Below, “Stabilizer (3)
)” was used.

Examples 1-13. Comparative Examples 1 to 3 Modified propylene polymers, propylene copolymers, CPP resins whose blending amounts are shown in Table 1], amorphous ethylene-propylene copolymers, propylene homopolymers (PP (as a resin), a high-density ethylene polymer, and 0.3 parts by weight of talc (average particle size: 2.0 microns, as a crystallization nucleating agent) were mixed for 5 minutes using a super mixer. Each of the obtained mixtures was passed through a vented twin-screw extruder (cylinder temperature 180-200°C, diameter 30mm).
+m) was used to produce pellets (composition) while kneading. Each pellet was used in a 5 oz. injection molding machine to produce flat plates (2 mm thick, 130 x 130 i+m) as well as specimens for measuring flexural modulus and Izod impact strength. The coating adhesion strength, Izot impact strength (measuring temperature -20"C), and flexural modulus of each specimen obtained were measured, as well as a gloss test and a weatherability test. The results are shown in Table 2. show.

(Left below) From the results of the above Examples and Comparative Examples, the propylene polymer composition obtained by the present invention is as follows.

It is clear that it not only has excellent mechanical strength (bending ratio, impact resistance), but also good workability, and also excellent adhesion to polyurethane. Furthermore, it is clear that the most distinctive effect is that by adding stabilizers against heat, oxygen, and ultraviolet rays, not only a synergistic effect is achieved, but also the appearance (gloss) is good. .

The propylene polymer composition obtained by the present invention is
It exhibits the following effects compared to conventional propylene polymer compositions.

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

(2) # The weatherability exhibited a synergistic effect as described above, which was a good result.

(3) Excellent adhesion with polyurethane coating I,
By applying polyurethane paint to the surface, the step of undercoating the primer can be omitted.

(4) The gloss is good, and even if a molded product is partially painted, a product with a good appearance can be obtained.

(5) Generally practiced activation treatment methods (for example,
By applying corona discharge treatment, plasma treatment method, ultraviolet treatment method) to the surface of the molded product.

It is possible to achieve even more satisfactory adhesion with polyurethane paints.

The propylene polymer composition of the present invention can be used in a wide variety of ways in order to exhibit the above-mentioned effects. Typical applications include outside products such as automobile bumpers and bumper corners.

Examples include interior parts such as door liners, fenders, and motorcycle parts such as -.

Claims (1)

Scope of Claims: (A) (1) 100 parts by weight of a mixture of a propylene polymer or a propylene homopolymer and an ethylene-propylene copolymer rubber contains (2) at least one unsaturated bond in the molecule; and (B) a modified propylene polymer obtained by treating with 0.1 to 50 parts by weight of an organic compound containing a hydroxyl group and (3) 0.01 to 20 parts by weight of an organic peroxide; Polymer, (C) Mooney viscosity [ML_l_+_4, (100°C)
] is 20 to 100, and the propylene content is 2
It is a composition consisting of an amorphous ethylene-propylene copolymer having an amount of 0 to 50% by weight and (D) a high-density ethylene polymer having a density of 0.935 g/cm^3 or more. The composition ratio of the density ethylene polymer is 3.0 to 25% by weight, and contains hydroxyl groups based on 100 parts by weight of the total amount of the modified propylene polymer, propylene polymer, and amorphous ethylene-propylene copolymer. The proportion of the organic compound is 0.01 to 10.0 parts by weight as a monomer unit,
and the composition ratio of the modified propylene polymer in the total amount of the modified propylene polymer and the propylene polymer is 5.
~90% by weight, and the composition ratio of the modified propylene polymer in the composition is at least 5.0% by weight,
A propylene polymer composition in which the composition ratio of the amorphous ethylene-propylene copolymer is 1.0 to 35% by weight.