JPH0273855A - Automotive exterior sheet using polyamide resin composition - Google Patents

Abstract

PURPOSE:To obtain an automotive exterior sheet, consisting of a resin composition, containing a polyamide resin, polyphenylene ether resin and elastomer and prepared by dispersing the polyphenylene ether resin into particles having a specified particle diameter and excellent in low-temperature impact resistance, heat resistance, etc. CONSTITUTION:An automotive exterior sheet obtained by molding a resin composition containing (A) a polyamide resin (preferably 6-nylon or 6,6-nylon) in an amount within the range of preferably 40-80wt.%, (B) a polyphenylene ether resin, preferably polyphenylene ether having carboxylic acid (derivative) groups or epoxy groups linked thereto in an amount within the range of preferably 10-50wt.% and (C) an elastomer, preferably a modified elastomer prepared by linking carboxylic acid (derivative) or epoxy groups to styrene-butadiene copolymer, etc., in an amount within the range of preferably 10-35wt.%. The component (A) forms a continuous phase and the dispersed phase of the component (B) dispersed in the above-mentioned continuous phase has <=0.6mum diameter.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automobile outer panel (7) using a polyamide resin composition.Recently, in the automobile industry, the purpose of reducing the weight of automobile bodies, etc. In recent years, there has been a trend to replace conventional metal parts with resin parts.Polyamide resin has excellent mechanical strength, oil resistance, abrasion resistance, and heat resistance, and is one of the representative engineer plus decks. Although it is used, the F method is stable (',
There are problems with moisture absorption.

-',','tl', polyphenidone ether resin is
It has excellent mechanical properties, electrical properties, heat resistance, etc.
[,2 is widely used in GL applications due to its properties such as good judicial stability, but
The major drawback is that it has poor impact resistance and oil resistance.

In recent years, attempts have been made to blend the two resins in order to take advantage of the characteristics of both resins described in 1 and to compensate for their shortcomings. However, this resin composition has a serious problem of being inferior in impact resistance, especially low-temperature impact resistance. Improved impact resistance 11. Various proposals have been made for compositions in which S lastomer is disposed in the dispersed phase.

For example, Japanese Patent Application Laid-Open No. 57-10642, (,, J S
f'4, 315. No. 086, USP 4.
421. No. 892, USP 4,600,741
No., JP-A-61-204261, JP-A-61-204
No. 262, JP-A-62-151456, JP-A-62-
No. 68850, JP-A-62-273254, JP-A-6
3-10656, JP-A-63-33471, JP-A-63-101452, and JP-A-63-146948. However, none of these compositions is satisfactory, especially in terms of low-temperature impact resistance.

Further, this composition has already been applied to Noryl GTX (GE) as an automobile exterior panel material. This composition is featured in Plastic Age, February issue.

It is introduced on pages 160-163 (1986),
The impact strength of Noryl GTX910 at 30'C is:
Approximately 13 kg-cm/Cm, heat distortion temperature (4.6 kg/c
The heat resistance shown in m2 load) is 190°C. The phase structure of this composition is such that polyphenylene ether resin is dispersed in a continuous phase of polyamide resin, and elastomer is further dispersed in polyphenylene ether resin.
The shape is characteristic of an island and lake, and the dispersed particles of polyphenylene ether resin have a particle size of 2 to 4 μm.Tokai Symposium "Material Characterization and Material Design++, sponsored by the Tokai Branch of the Society of Polymer Science and Technology, ll. Abstracts, pages 53-58 (January 1987).

[Problems to be Solved by the Invention] The present invention provides impact resistance, particularly low-temperature impact resistance, and heat resistance.
The object of the present invention is to obtain an automobile outer panel using a polyamide resin composition having excellent flexural modulus.

[Means for Solving the Problems] In view of the above-mentioned problems, the inventors of the present invention, as a result of intensive studies, have determined that, in a resin composition consisting of a polyamide resin, a polyphenylene ether resin, and an elastomer, the polyphenylene ether resin has a specific particle size. It has been discovered that the above problems can be solved by dispersing it, and the present invention has been completed.

That is, the present invention provides a composition containing (a) a polyamide resin, (b) a polyphenylene ether resin, and (C) an elastomer, wherein the polyamide resin forms a continuous phase and polyphenylene dispersed in the polyamide resin. The present invention provides an automobile outer panel using a polyamide resin composition characterized in that the diameter of the dispersed phase of ether resin is 0°6 μm or less.

The biryamide resin used as component (a) in the present invention may be a known polyamide resin used in ordinary injection molding, and is a polymer having a -CONH- bond in the main chain and can be melted by heating. . Typical examples include 4-nylon, 6-nylon, 6,6-nylon, 4°6-nylon, 12-nylon, 6,10-nylon.
- polyamides from nylon, terephthalic acid and/or isophthalic acid and hexamethylene diamine, polyamides from terephthalic acid and trimethylhexamethylene diamine, polyamides from adipic acid and metaxylylene diamine, terephthalic acid and 4+4'-diaminodicyclohexyl Examples include polyamide made from methane. Among these, 6-nylon and 6,6-nylon are particularly preferred.

In the present invention, the polyphenylene ether resin used as component (b) has the following general formula % formula % () (wherein R1, R2, R3, R4, R5, R6 are the same or different tart- It is a monovalent residue such as an alkyl group having 1 to 4 carbon atoms excluding a butyl group, an aryl group, hydrogen, or a halogen, and R5 and R6 are not hydrogen at the same time.) is the repeating unit, and the structural unit is (1) Alternatively, they include a homopolymer or copolymer consisting of (■) and (I[), and a graft copolymer obtained by graft polymerizing styrene or the like to the polymer. Reduced viscosity (0.5 g/di,
Chloroform solution, 30°C, measurement) is 0.15~
Range of 0.70, from ψf(, <, 0.2(→~0
．． The range is 60.

Specific examples of (2) include poly(2,6-dimethylphenylene-1,4-ether), poly(2,6-dimethylphenylene-1,,4-ether), poly(2,6-dimethylphenylene-1,,4-ether), cyclophenylon-1,4-ethyl), poly(2,6-
dibromphenylene-1゜4-ether), poly(2-
Methyl-6-ethylphenylene 1,4-ether), poly(2-chloro-(3-methylphenylene-1,4-
ether), poly(2-methyl 6-propylphenylene 1,4-ether), poly(2,6-di-11
probylbuenylene-1,4-ether), poly(2-
ILI Roux 6-promphenitone-1,4 ether)
, poly(2-chloro-6-nitylphenylene=-1,4
-ether), poly(2=-methylphenylene-1,4
-ether), poly(2-chlorophenylene-1,4-
copolymers of tele, such as poly(2-buenylbuenitone-1,4-ether), poly(2-pro8-6-buenylphenylene), . It is a graft copolymer of these styrene compounds.

In the present invention, the elastomer that can be used in conjunction with component (8) is an elastomer that is intended to improve impact resistance and has a glass transition point of 1!Ii below 0°C and is an elastomer at room temperature. It is a substance with a shape of

For example, polybutadiene, fl-butadiene copolymer, styrene-isoprene copolymer, acrylonitrile-styrene-butadiene copolymer, ethylene-α-olefin copolymer, ethylene-α-olefin–polyene copolymer itself acrylic Rubbery polymers such as rubber and polyisoprene, as well as styrene-butadiene block copolymers, styrene-isoprene block copolymers, hydrogenated styrene-butadiene block copolymers, styrene-grafted ethylene-propylene elastomers, and ethylene ionomers. There are thermoplastic elastomers such as resins, and these polymers can also be modified with carboxyl groups, acid anhydride groups, epoxy groups, hydroxyl groups, amine groups, etc.

Preferred elastomers include styrene-butadiene copolymers, ethylene-α-olefins, polymers, styrene-butadiene block copolymers, hydrogenated styrene-
Examples include butadiene copolymers, and those modified with carboxyl groups, acid anhydride groups, n-boxy groups, etc. are more preferred.Styrene-butadiene block copolymers and styrene-isoprene block copolymers are more preferred. Polymers include those having AB type, ABA type, ABA tapered type, radial teleblock type structures, etc.3 In the resin M substitute of the present invention, a composition containing a polyamide resin, a polyphenylene ether resin, and an elastomer. If the polyamide resin forms a continuous phase and the diameter of the dispersed phase of the polyphenylene ether resin dispersed in the polyamide resin is 0.6 μn1 or less, the composition ratio of the resin components is not limited. do not have.

The preferred composition ratio of the resin components is polyamide 1! The blending amount of lubricant is in the range of 40-80 wt%, more preferably 45-65 wt%. A wood groove of 40 wt% is not preferable because it becomes difficult for the polyamide resin to form a continuous phase, which may result in a decrease in oil resistance. If it exceeds 80 wt%, hygroscopicity increases, which is not preferable.

The blending amount of the polyphenylene ether resin is preferably in the range of 10 to 50 wt%, more preferably in the range of 15 to 45 wt%.

If it is less than 10 wt%, dimensional stability deteriorates, which is undesirable. If it exceeds 50 wt%, 2. moldability deteriorates, which is not preferred.

, the blending amount of the elastomer is preferably 2 to 10 to 35 w.
11%, more preferably in the range of 15 to 25 wt%.

If it exceeds 35 wt%, the rigidity decreases, which is not preferable.

In the present invention, the dispersed structure of the resin composition can be observed using a transmission electron microscope in an ultrathin section that has been stained and fixed using osmium tetroxide and/or ruthenium tetroxide. The dispersion structure of the present invention is made of polyamide, but Il! It is a continuous phase, and polyphenidone-terugoji-shi forms a dispersed phase.

The diameter of the polyphenylene ether resin dispersed phase in the resin composition of the present invention is such that most of the polyphenylene ether resin dispersed phase has a diameter of 0. It is 6 μm or less.

When the number of particles exceeding 0.6 μm increases, impact resistance decreases.

The polyphenylene ether resin dispersed phase in the resin composition of the present invention is mostly 0. For automobile outer panels using a resin composition with a diameter of 6 μm or less, when the elastomer is a partially hydrogenated styrene-butadiene block copolymer, the Izot strength at -30°C is 31 kg-cm/cm, and the heat distortion temperature is 172.
°C, flexural modulus 18300 kg/cm2
This shows superior performance compared to those with many particles exceeding 0.6 μm.

The measurement of the polyphenylene ether resin dispersed phase was carried out at a photographic magnification of 10,000 times, and when it was elliptical, a perpendicular line was drawn at the center of the long axis and the long axis, and the distance between the intersections with the W1 circle was measured as the short axis, Let D obtained from the formula D=(major axis+minor axis)/2 be the diameter of the dispersed phase.

The method for producing the resin composition of the present invention includes a modified polyphenylene ether resin in which a carboxylic acid and its derivative group or an epoxy group is bonded to a polyphenylene ether resin, and a modified polyphenylene ether resin in which a carboxylic acid and its derivative group or an epoxy group is bonded to an elastomer. The modified elastomer
A method of melt-kneading the polyamide resin is preferred.

In the present invention, the modified polyphenylene ether resin preferably used can be obtained, for example, by reacting a polyphenylene ether resin with a 2-substituted olefin compound having a carboxylic acid and its derivative group or an epoxy group in the presence of a radical generator. It will be done.

Specific examples of 2-substituted olefin compounds having a carboxylic acid group, acid anhydride group or epoxy group to be reacted with the polyphenylene ether resin include maleic anhydride, maleic acid, itaconic anhydride, fumaric acid, methylnadic anhydride, Examples include dichloromaleic acid, acrylic acid, methacrylic acid, glycidyl methacrylate, and the like.

The radical generator represents a known organic peroxide or diazo compound, and specific examples include benzoyl peroxide, dicumyl peroxide, butyl peroxide, cumene hydroperoxide, azobisisobutyronitrile, etc. can be mentioned. Two or more of these radical generators can also be used in combination.

The method for producing the modified polyphenylene ether resin used in the present invention is not limited in carrying out the present invention, and for example, the following method can be used.

1) Special Publication No. 52-30991, Special Publication No. 52-19
As disclosed in Japanese Patent No. 864, a 2-substituted olefin compound having a carboxylic acid group, an acid anhydride group, or an epoxy group is added to a solution containing a polyphenylene ether resin in the presence of a radical generator, and the mixture is heated at 50 to 200°C. A method of stirring at a certain temperature for several tens of minutes to several hours.

2) As disclosed in Japanese Patent Publication No. 59-11605, a method in which each component is brought into contact with each other under melt mixing in a system substantially free of solvent or a system containing a small amount of solvent.

In the present invention, the modified elastomer preferably used includes, for example, the elastomer in the presence of a radical generator,
It is obtained by reacting a 2-substituted olefin compound having a carboxylic acid and its derivative group or an epoxy group.

Specific examples of 2-substituted olefin compounds having a carboxylic acid group, acid anhydride group, or epoxy group to be reacted with the elastomer include maleic anhydride, maleic acid, itaconic anhydride, fumaric acid, methylnadic anhydride, and dichloromaleic anhydride. acid, acrylic acid.

Examples include methacrylic acid and glycidyl methacrylate.

The radical generator represents a known organic peroxide or diazo compound, and specific examples include benzoyl peroxide, dicumyl peroxide, 7-butyl peroxide, cumene hydroperoxide, azobisisobutyronitrile, etc. can be mentioned. Two or more of these radical generators can also be used in combination.

The method for producing the modified elastomer used in the present invention is not limited in carrying out the present invention.

The resin composition of the present invention may contain other components such as raw materials, dyes, heat stabilizers, antioxidants, weathering agents, nucleating agents, lubricants, plasticizers, etc., to the extent that their moldability and physical properties are not impaired. Antistatic agents, other polymers, etc. can be added during any manufacturing/molding process.

The resin composition of the present invention can be prepared by mixing it in a molten state using various mixing apparatuses commonly used for mixing polymeric substances. Suitable mixing devices include, for example, a screw-type or multi-screw extruder, a mixing roll, a Banbury mixer-kneader, a Brabender, and the like.

The resin composition of the present invention can be easily processed into molded articles of various shapes by any conventionally known molding method, such as injection molding or extrusion molding.

[Function] In the polyamide resin composition of the present invention, the particle size of the polyphenylene ether resin of the dispersed phase is 0. When it is 6 μm or less, an automobile outer panel using a polyamide resin composition with excellent impact resistance, particularly low-temperature impact resistance, heat resistance, and flexural modulus can be obtained.

[Example] The present invention will be described below with reference to Examples, but the present invention is not limited thereto. In the examples, "r parts" indicates "parts by weight."

In addition, the physical properties of the resin compositions in Examples were measured by the following method.

1) r# Impact Strength Izot impact strength was measured according to ASTM D-256 using a 1/8" thick notched test piece at 23 DEG C. in an absolutely dry state.

2) Impact resistance Using a notched test piece with a thickness of 1/8'', at -30℃,
Izod impact strength was measured in an absolutely dry state according to ASTM D-256.

3) Using an injection molded piece with a heat distortion temperature of 1/8” thickness, ASTMD-
638, the heat distortion temperature at 4.6 kg/cm2 was measured.

4) Using a rigid 1/8” thick injection molded piece, ASTM D-
The flexural modulus was measured using 790-80.

[Example 1] (a) Production of maleic anhydride-modified polyphenylene ether resin For 100 parts of poly(2,6-dimethylphenylene-1,4-ether) (hereinafter referred to as PPE) with a number average degree of polymerization of 140, After tri-blending 1 part of di-t-butyl peroxide and 3 parts of maleic anhydride at room temperature, the mixture was triblended using a co-rotating vented twin-screw extruder (manufactured by Ikegai Iron Works) with a diameter of 65 mmφ and L/D = 30. using cylinder temperature 3
It was melted at 00°C and a screw rotation speed of 70 rpm, extruded for a residence time of 70 minutes, cooled with water, pelletized, and formed into maleic anhydride-modified poly(2,6-dimethylphenylene 1.4
-ether) (hereinafter referred to as MPPE) was obtained.

The resulting MPPE pellet was dissolved in chloroform and then reprecipitated into about 10 times the amount of acetone for purification. After drying this purified MPPE, 50 mg was collected and dissolved in chloroform to create a cast film with a thickness of about 50 μm. This film was then dried and used as a sample for infrared spectroscopy. The presence of a -(Co)20= structure derived from the reaction with maleic anhydride in this sample was confirmed by an absorption peak near 1780 cm-' in the infrared absorption spectrum.

(b) Hydrogenated styrene tadiene block copolymer of maleic anhydride-modified elastomer III product (manufactured by Shell Chemical Company, Kraton Gl
652. Styrene content 29%, type 5EBS, where S stands for styrene and EB stands for ethylene butylene.

) 1.2 parts by weight of maleic anhydride per 100 parts by weight, 0. After uniformly mixing 3 parts by weight of Parhexa 25B (NOF [)], a twin-screw extruder (screw diameter 65 mm) was used.
; L/D=3O, with a vent) and suctioned from the vent to remove unreacted maleic anhydride.
The maleic acid addition reaction was carried out at a cylinder temperature of 260°C. One analysis of this modified elastomer after drying under reduced pressure with heat revealed that the amount of maleic anhydride added was 0.6% by weight. Incidentally, the additional flow of maleic anhydride was determined by titration using sodium methylate.

(C) 1 Preparation of composition Nylon 6.6 (manufactured by Asahi Kasei Corporation, Leona 1300)
After tri-blending 30 parts of the MPPE obtained in (a) and 20 parts of the maleic anhydride-modified elastomer obtained in (b), a co-rotating twin-screw extruder (Hoseitetsu Co., Ltd.) with a cylinder temperature of 280°C was used. ), diameter 45mmφ
, L/D=33), and after cooling, pelletized to obtain a pelletized resin composition.

This wood am substitute was dried at 80° C. for 8 hours and then injection molded at a cylinder temperature of 290° C. to prepare a test piece for measuring physical properties.

The evaluation is shown in Table 1.

As is clear from Table 1, the Izot strength is extremely excellent even at 30°C, and the heat resistance and flexural modulus are also excellent. The PPE particle size of the dispersed phase was mostly 0.6 μm or less.

[Comparative Example 1] Nylon 6.6 (M Kasei Kogyo Co., Ltd. ll, Leona 130
The same procedure as in Example 1 was carried out by triblending 30 parts of PPE, 30 parts of maleic anhydride-modified partially hydrogenated styrene-butadiene block copolymer.

As is clear from Table 1, all samples are inferior to Example 1. The PPE particle size of the dispersed phase was approximately 4.3 μm.

[Comparative Example 2 Conylon 6,6 (manufactured by Asahi Kasei Corporation, Leona 1300)
The same procedure as in Example 1 was carried out using a tri-blend of S), 30 parts of MPPE, and 20 parts of partially hydrogenated styrene-butadiene block copolymer.

As is clear from Table 1, all samples are inferior to Example 1. The PPE particle size of the dispersed phase was approximately 1.4 μm.

[Comparative Example 3] Nylon 6.6 (manufactured by Asahi Kasei Corporation, Leona 1300)
s), MPPE30 with a small amount of added maleic anhydride
Example 1
It was carried out in the same way.

As is clear from Table 1, the isot strength is inferior to that of Example 1. The PPE particle size of the dispersed phase is approximately 2.0 μm.
Met.

[Example 2 Conylastomer was converted into modified ethylene-propylene copolymer (E
The same procedure as in Example 1 was carried out using MPPE and nylon 6.6 (Leona 1300S, manufactured by Asahi Kasei Industries, Ltd.) in place of MPPE (Exxelor VA1803).

As is clear from Table 1, the Izot strength is extremely excellent even at 30'C, and the heat resistance and flexural modulus are also excellent. The PPE particle size of the dispersed phase was mostly 0.6 μm or less.

[Example 3] The elastomer was modified with a modified ethylene-propylene copolymer (E
xxon Exxelor VA1803),
The same procedure as in Example 1 was carried out using MPPE and nylon 6 (Ube Industries, Ltd., 1013B).

As is clear from Table 1, the Izot strength is extremely excellent even at 30°C, and the heat resistance and flexural modulus are also excellent. The PPE particle size of the dispersed phase is mostly 0. It was 6 μm or less.

[Effects of the Invention] As is clear from the above, the present invention uses a polyamide resin composition that has superior low-temperature impact resistance, heat resistance, and flexural modulus compared to conventional materials. It is possible to provide an automobile exterior panel with a high quality.

[Brief explanation of the drawing]

The drawing is a perspective view of the front section according to the invention.

Claims (2)

[Claims] (1) A resin composition consisting of (a) a polyamide resin, (b) a polyphenylene ether resin, and (c) an elastomer, wherein the polyamide resin forms a continuous phase, and the polyphenylene ether resin is dispersed in the polyamide resin as a dispersed phase. An automobile outer panel using a polyamide resin composition characterized in that the diameter is 0.6 μm or less. (2) (a) Polyamide resin 40-80wt%, (b)
Polyphenylene ether resin 10-50wt% and (
c) An automobile outer panel using the polyamide resin composition according to claim 1, characterized in that it is comprised of 10 to 35 wt% of elastomer.