JPH03259941A - Polypropylene resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition excellent in the balance among solvent resistance, heat resistance, rigidity and impact strength and good in moldability and appearance by mixing a polypropylene resin with a polyphenylene resin, a block copolymer and a particulate rubbery polymer. CONSTITUTION:A resin composition comprising 30-60wt.% polypropylene resin, 20-55wt.% polyphenylene ether resin, 2-5wt.% block copolymer of formula I or II and 8-30wt.% particulate rubbery polymer of a mean particle diameter of 0.08-2mum. In the formulas, A is a styrene polymer block, and B is an isoprene polymer block, a hydrogenated butadiene polymer block or a hydrogenated isoprene polymer block. It is desirable that the content of component A in the block copolymer be in a range of 20-30wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel polypropylene resin composition, more specifically, it has an excellent balance between impact strength and rigidity, as well as good moldability, solvent resistance, heat resistance, It has appearance etc.
For example, the present invention relates to a polypropylene resin composition suitable as a material for automobile parts such as fenders and bumper foil covers.

Conventional Technology Polypropylene resins have been widely used as materials for miscellaneous goods, daily necessities, automobiles*, parts, etc. due to their excellent solvent resistance, moldability (fluidity), and impact resistance. However, this polypropylene resin has poor rigidity, especially at high temperatures, and lacks dimensional stability due to its large coefficient of expansion. It has the disadvantage that it cannot be used for many purposes, and its applications are inevitably limited.

On the other hand, although polyphenylene ether resin has excellent heat resistance and impact resistance, it has extremely poor moldability and is extremely difficult to injection mold as a single product. In order to improve these drawbacks, a material with relatively well-balanced moldability, impact resistance, and heat resistance was developed by blending the polyphenylene ether resin with a polystyrene resin, and it has become one of the engineering plastics. However, although this product has poor solvent resistance and has improved moldability, it cannot be said to have a sufficient balance with heat resistance.

On the other hand, in order to obtain a material that has both the heat resistance and good mechanical properties of a polyphenylene ether resin and the solvent resistance and good moldability of a polyolefin resin, a composition consisting of a blend of both has been proposed ( Special Public Service 1977-706
Publication No. 9). However, in this composition, solvent resistance and moldability are not necessarily sufficient, and when the amount of polyolefin resin blended is increased in an attempt to further improve these properties, the compatibility of both resins is As a result, delamination occurs in the molded product, resulting in a problem of deterioration in appearance and mechanical strength.

Therefore, in order to improve the compatibility between polyphenylene ether resin and polyolefin resin and improve mechanical strength, we added styrene-butadiene block copolymer to a mixture of polyphenylene ether resin and polyolefin resin. Various compositions containing combinations and hydrogenated products thereof have been disclosed (JP-A-53-71158, JP-A No. 54-88960, JP-A No. 56-51356, JP-A No. 58-103556, JP-A No. 58-58). -1035
Publication No. 57, Publication No. 59-100159, Publication No. 59-1
No. 40257, No. 60-76547, No. 60
No. 120748, No. 63-83149, No. 6
No. 3-113047, No. 63-113048, No. 63-113049, No. 63-113050
No. 63=118344, No. 63-122
No. 755, No. 63-122756, No. 63-
No. 122757, No. 63-125543, No. 63-218748, No. 63-225642, No. 63-241064, No. 63-24545
Publication No. 3, Publication No. 64-40556, JP-A-1-98
No. 647, No. 1-139636, No. 1-20
Publication No. 4939). However, none of these compositions can be said to be well-balanced in terms of heat resistance, mechanical properties, solvent resistance, and moldability. For example, even if the moldability and mechanical strength have been improved to some extent, the amount of polyolefin resin blended is small and the continuous phase is polyphenylene ether resin or a combination of this and a styrene block copolymer. It has the disadvantage that the solvent resistance of the resin is not sufficiently exhibited.

In addition, a large amount of polyolefin resin exceeding 20% by weight is blended with the polyphenylene ether resin, and a diblock copolymer or radial teleblock copolymer containing an alkenyl aromatic compound and a conjugated diene compound is further added as a compatibilizer. Coalescence and compositions modified by adding these hydrogenated polymers have also been proposed (Japanese Patent Application Laid-Open No. 1983-1989)
-103557, 60-76547).

However, although this composition has improved compatibility, tensile properties, and brittleness, it uses low-density polyethylene as the polyolefin resin.
It cannot be said that the relatively high level of rigidity, heat resistance, and impact strength improvements required in the field of industrial parts are necessarily satisfied.

Furthermore, compositions containing polypropylene as a polyolefin resin with increased heat resistance, rigidity and impact strength have been proposed (JP-A-63-83149 and JP-A-63-113047). However, in order to sufficiently satisfy the impact strength of the hydrogenated alkenyl aromatic compound-conjugated diene block copolymer in the composition, as is clear from the examples, 9% by weight or more must be added. It is necessary to blend a large amount of the alkenyl aromatic compound-conjugated diene block copolymer, and as a result, the hydrogenated product of the alkenyl aromatic compound-conjugated diene block copolymer is treated with a compatibilizer.
), since it is mainly located at the interface between the polypropylene phase and the polyphenylene ether phase, external stress is absorbed by the hydrogenated product of the alkenyl aromatic compound-conjugated diene block copolymer, and the polyphenylene in the dispersed phase not sufficiently transmitted to the ether phase. Although this form is advantageous in terms of increasing impact strength, stress is not transmitted to the poly7-ethylene ether phase, so the high heat resistance and high rigidity of polyphenylene ether are not fully demonstrated, and as a result, A problem arises in that they provide much lower levels of stiffness and heat resistance than simple compositions of polypropylene and polyphenylene ether.

In this way, a well-balanced material with relatively high levels of solvent resistance, heat resistance, rigidity, and impact strength that uses polypropylene resin as a continuous phase and polyphenylene ether resin as a dispersed phase has not yet been found. is the reality.

Problems to be Solved by the Invention Under these circumstances, the present invention uses polypropylene resins and polyphenylene resins that have an excellent balance of solvent resistance, heat resistance, rigidity, and impact strength, as well as good moldability and appearance. This was developed with the aim of providing a material whose main component is ether resin.

Means for Solving the Problems As a result of intensive research to develop a material having the above-mentioned preferable properties, the present inventors discovered that polypropylene resin, polyphenylene ether resin, and a specific block copolymer in a predetermined ratio. It was discovered that the object could be achieved by a composition comprising a particulate rubbery polymer having a predetermined particle size, and based on this knowledge, the present invention was completed.

That is, the present invention provides (a) polypropylene resin 30
~601% by weight, (b) polyphenylene ether resin 20
~55% by weight, (c) General formula % Formula % () A- (B-A is a styrene polymer block, B is an isoprene polymer block, a hydrogenated butadiene polymer block, and a hydrogenated isoprene polymer block) at least one selected type, n is an integer of 1 or more) or (A-B)n...(II)A-
(B-A, B and n have the same meanings as above) 2 to 5% by weight of a block copolymer and (d) 8 to 8% of a particulate rubbery polymer with an average particle size of 0.08 to 2 μm A polypropylene resin composition comprising 30% by weight is provided.

The present invention will be explained in detail below.

In the composition of the present invention, the polypropylene resin used as the component (a) is, for example, a propylene homopolymer having crystallinity, a copolymer portion consisting of an ethylene propylene random copolymer with a small content of ethylene units, or a propylene resin. A substantially crystalline product commercially available as a so-called propylene block copolymer, which is composed of a homopolymer portion consisting of a homopolymer and a copolymer portion consisting of an ethylene propylene random copolymer with a relatively high content of ethylene units. A commercially available crystalline block copolymer of propylene and ethylene, or each homopolymer part or copolymer part in this block copolymer is further copolymerized with an α-olefin such as butene-1. Preferred examples include propylene-ethylene-σ-olefin copolymer.

In the present invention, these polypropylene resins are
A rubbery copolymer consisting of two or more types of α-olefin units, preferably 70% by weight or more of propylene units and other α-olefin units. It may be used in combination with an a-olefin rubbery polymer comprising 30% by weight or less.

When polypropylene and a σ-olefin rubber-like polymer are used in combination, it is necessary to contain at least 50 parts by weight of polypropylene out of 100 parts by weight of the total amount.

In addition, as the polypropylene resin, MFR (23
0℃, 2.16bg) is 0.1~Loog/10 minutes,
Preferably in the range of 0.3 to 609/l 0 min, more preferably in the range of 0.5 to 3 h/10 min, and C"-NM
Based on R<mm die and tacticity is 95 or more,
It is preferably 97 or more, more preferably 98 or more.

If the MFR is less than O, 1g/10 minutes, the moldability will be poor and the surface appearance may be damaged.
g/l If it exceeds 0 minutes, there is a tendency for the impact strength to decrease. Furthermore, if the tacticity is less than 95, the value of heat sag at a temperature of 150'O, which is an index of heat resistance, becomes large, which may lead to thermal deformation due to the composition's own weight in a high-temperature environment.

In the composition of the present invention, the content of the polypropylene resin as component (a) is as follows: (a), (b), (c) and (
d) It is necessary to choose between 30 and 60% by weight based on the total amount of components. If this amount is less than 30% by weight, solvent resistance and moldability will be poor, and if it exceeds 60% by weight, rigidity and heat resistance will tend to decrease.

In the composition of the present invention, the polyphenylene ether resin used as the Iffi component (b) has the general formula A- (B-R1 and R2 are each a hydrogen atom, A secondary branched alkyl, hydroxyalkyl or haloalkyl group, preferably having 1 to 4 carbon atoms, or an aryl group,
R1 and R2 may be the same or different from each other, but they cannot be hydrogen atoms at the same time) and a homopolymer consisting of a repeating unit represented by the above general formula (I) Repeating unit and general formula A-(B-
R3, R1, R5 and R6 are each a hydrogen atom, a halogen atom, a linear, primary or secondary branched alkyl, hydroxyalkyl or haloalkyl group having preferably 1 to 4 carbon atoms, or an aryl group. Based on
These may be the same or different, but a copolymer consisting of a repeating unit represented by R3 and R' cannot be hydrogen atoms at the same time can be used.

Typical examples of polyphenylene ether homopolymers include:
Poly(2,6-dimethyl-1,4-phenylene) ether, poly(2,6-diethyl-1,4-7 enylene) ether, poly(2,6-di-n-propyl-1,4-phenylene) ether , poly(2,6-cyclo1.4
-phenylene)ether, poly(2,6-dipromo 1)
．． 4-phenylene)ether, poly(2-methyl-6-
Nity-1,4-phenylene) ether, poly(2-methyl-6-isopropyl-1,4-phenylene) ether, poly(2-2thyl-6-n-butyl-1,4-phenylene) ether, poly (2-methyl-6-hydroxyethyl-1,4-7 enylene) ether, poly(2-methyl-6-7 enyl-1,4-7 enylene) ether,
Poly(2-methyl-1,4-phenylene) ether, poly(2-ethyl-6-itsuprobyl-1,4-)dinidine) ether, poly(2-ethyl-6-n-propyl-1, 4-phenylene)ether, poly(2,3,6-
Dolimethyl-1,4-phenylene)ether, poly(2
,3-dimethyl-6-ethyl-1,4-phenylene)ether, polyC2-(4'-methylphenyl)-1,4
-phenylene]ether, poly(2-phenyl-1,4
-phenylene)ether, poly(2-chloro-1,4-
7-enylene) ether, poly(2-chloro-6-methyl-1,4-phenylene) ether, poly(2-chloro-
6-Nityru(1.4-)22)ether, poly(2
-bromo-6-phenyl-1,4-7 enylene) ether, poly(2-chloro-6-bromo-1,4-7 enylene) ether, poly(2-methyl-6-chloroethyl-
Examples include homopolymers such as 1,4-phenylene) ether.

On the other hand, in the case of polyphenylene ether copolymer, 2.
6-dimethylphenol and alkyl substitution such as 0-cresol or 2,3,6-drimethylphenol represented by the general formula R6R3 A- (B-R3, R4, R5 and R6 have the same meanings as above) Examples include polyphenylene ether copolymers obtained by copolymerizing with phenol.

Among these polyphenylene ether resins, poly(2
, 6-dimethyl-1,4-phenylene)ether and 2
,6-dimethylphenol and 2,3,6-dimethylphenol are preferred, especially poly(2,6-dimethylphenol).
Dimethyl-1,4-7enylene) ether is preferred.

In addition, the polyphenylene ether resin of component (b) may be used alone or in combination of two or more types, or may be used as a mixture with a polystyrene resin or a polyphenylene ether graft polymerized with a polystyrene resin. A graft polymer may also be used. When polystyrene having a syndiotactic structure is used as the polystyrene resin, a composition having excellent solvent resistance can be obtained.

The polystyrene resin may be homopolystyrene obtained by polymerizing styrene monomers by a polymerization method such as bulk polymerization, suspension polymerization, or bulk-suspension polymerization, or a homopolystyrene obtained by blending polystyrene with a rubbery polymer. Styrene is obtained by polymerizing styrene in the presence of rubber-modified polystyrene or a rubber-like polymer, and a portion of the styrene is graft-polymerized to the rubber-like polymer, and the remainder of the styrene becomes polystyrene, resulting in a substantially rubber-like polymer. It may be rubber-modified polystyrene in which a polymer/styrene graft copolymer and polystyrene are mixed, so-called high-impact polystyrene, and its weight average molecular weight is 100,000 to 500,000, preferably 150,000 to 150,000. 400,000, more preferably in the range of 180,000 to 330,000. When the weight average molecular weight is less than 100,000, mechanical strength is insufficient, and when it exceeds 500,000, moldability tends to deteriorate. This polystyrene resin is desirably 70% by weight or less of the total amount of component (b).

The polyphenylene ether resin of the component (b) is heated at 30°C.
Intrinsic viscosity in chloroform is 0.25-0.6d4/g
, preferably in the range of 0.3 to 0.52 dQ/g. If the intrinsic viscosity is less than 0.25 d (2/g), the mechanical strength of the composition is insufficient,
If it exceeds 0.6 d12/g, the moldability of the composition deteriorates.

In the composition of the present invention, the content of the polyphenylene ether resin as the component (b) is as follows: (a), (b), (c)
and (d) It is necessary to select the amount in the range of 20 to 55% by weight based on the total amount of II component. If this amount is less than 20% by weight, heat resistance and rigidity will be insufficient, and if this amount exceeds 55% by weight, moldability and solvent resistance will decrease.

In the composition of the present invention, a block copolymer represented by the general formula %() () is used as component (C). A in the general formulas (I) and (II) is a styrene polymer block, and in formula (I), the degree of polymerization may be the same or different at both ends of the molecular chain. B is at least one selected from isoprene polymer blocks, hydrogenated butadiene polymer blocks, and hydrogenated isoprene polymer blocks. Further, n is an integer of 1 or more.

The content of component A in the block copolymer is 20 to
It is desirable that the amount is 80% by weight, preferably in the range of 30 to 70% by weight. If this amount is less than 20% by weight, the rigidity will be poor, and if it exceeds 80% by weight, moldability and impact strength will tend to decrease, which is not preferable.

In addition, the number average molecular weight per single block of component A is 5
．． 000 to 200,000, and the number average molecular weight per block of component B is 5,000 to 200,000.
It is desirable that the value be in the range of 00. If the number average molecular weight per single block of component A is less than 5,000, or if the number average molecular weight per block of component B is less than 5,000, the mechanical properties are insufficient, and the When the number average molecular weight per single block exceeds 200,000, or when the number average molecular weight per block of component B is 200,
If it exceeds 000, moldability tends to decrease, which is not preferable. Furthermore, the number average molecular weight of the block copolymer as a whole is preferably in the range of 10,000 to 400,000; if the number average molecular weight is less than 10,000, the mechanical properties will be poor; This is not preferable because it tends to reduce moldability.

Specific examples of such block copolymers include styrene-hydrogenated butadiene-styrene triblock polymers,
Examples include styrene-isoprene-styrene triblock polymer, styrene-hydrogenated isoprene-styrene triblock polymer, styrene-hydrogenated isoprene diblock polymer, styrene-isoprene diblock polymer, styrene-hydrogenated butadiene diblock polymer.

In the composition of the present invention, one type of component (c) may be used, or two or more types may be used in combination, and the content thereof may vary depending on (a), (b), (c) and It is necessary to select the amount in the range of 2 to 5% by weight based on the total amount of component (d). If this amount is less than 2% by weight, the compatibility between the polypropylene resin and the polyphenylene ether resin is insufficient,
There is a risk of delamination in the molded amount and a decrease in impact strength, and if it exceeds 5% by weight, it will lead to a decrease in rigidity and heat resistance.

In the composition of the present invention, a particulate rubbery polymer is used as the (d) rR component. This rubbery polymer is
For example, one or more monomers selected from vinyl group-containing carboxylic acid esters such as alkyl acrylates and alkyl methacrylates, polyfunctional monomers having conjugated diene type double bonds, and siloxanes, or A particulate elastic body obtained by graft polymerizing a vinyl compound to a rubbery polymer obtained by polymerizing a combination of these monomers and acrylic acid or methacrylic acid is used. In particular, it is preferable to polymerize the monomers in combination with acrylic acid or methacrylic acid, as this promotes enlargement of the resulting rubbery polymer.

The vinyl group-containing carboxylic acid ester is preferably one in which the alkyl group in the ester moiety has 2 to 10 carbon atoms, such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, n-octyl methacrylate, etc. Examples of polyfunctional monomers having a conjugated diene type double bond include conjugated diene compounds such as butadiene and isoprene, 1-methyl-2-vinyl-4,6-hebutadien-1-ol, 7-methyl-
Compounds having a non-conjugated double bond in addition to a conjugated diene type double bond in the molecule, such as 3-methylene-6-octadiene and 1.3.7-octatriene, are included.

Examples of the vinyl compound to be graft-polymerized to the rubbery polymer include aromatic vinyl compounds such as styrene and a-methylstyrene, acrylic esters such as methyl acrylate and ethyl acrylate, methyl methacrylate, and ethyl methacrylate. Examples include methacrylic acid esters, vinyl cyanide compounds such as acrylonitrile and methacrylate, and vinyl esters such as vinyl acetate and vinyl propionate.

These vinyl compounds may be used alone or in combination of two or more, but when graft polymerization is carried out using at least an aromatic vinyl compound, the resulting particulate rubbery polymer (b It is preferable from the viewpoints that the compatibility with the polyphenylene ether resin of the component () becomes good, most of the component (d) is dispersed in the component (b) phase, and rigidity is maintained.

There are no particular limitations on the graft polymerization method, and any method such as bulk polymerization, suspension polymerization, or emulsion polymerization can be used, but among these, emulsion polymerization is particularly preferred.

The average particle size of the particulate rubbery polymer for Ifi (d) is 0.08 to 2 μm, preferably 0.15 to 1.5 μm+
It is necessary to be in the range of ++. If this average particle size is outside the above range, the effect of improving the impact resistance of the resulting composition will not be sufficiently exhibited. This particle size can be adjusted, for example, by adjusting the polymerization conditions during emulsion polymerization, and the longer the polymerization time, the larger the particle size tends to be.

In addition, a method for coagulating rubbery polymers (Japanese Patent Application Laid-Open No. 60-1999)
229911, 58-63713), it is possible to obtain an enlarged particle size.

A preferable example of this (d) tC content is 70% by weight or more of a rubbery polymer mainly composed of alkyl acrylate units or alkyl methacrylate units, and 30% by weight or less of other vinyl compounds copolymerizable therewith. Examples include graft copolymers obtained by graft polymerization.

In this case, a polymer obtained by appropriately adding and reacting a polyfunctional monomer such as divinylbenzene, ethylene dimethacrylate, triallyl cyanurate, or triallyl isocyanurate as a crosslinking agent is also included.

A specific example of such a material is a MAS elastic body [manufactured by Rohm & Haas, trade name: KM- 33
0, EX L-23301 manufactured by Kanebuchi Chemical Industry Co., Ltd.
MAR5 elasticity obtained by graft polymerizing styrene and methacrylic acid to a rubbery latex obtained by copolymerizing octyl acrylate and butadiene at a weight ratio of 7:3. MBS elastomer obtained by graft polymerizing styrene to a rubbery latex obtained by copolymerizing methyl methacrylate and butadiene [manufactured by Mitsubishi Rayon Co., Ltd.]
Commercially available products are Metablane C223 (trade name), KCA201 (manufactured by Kureha Chemical Co., Ltd.), which is obtained by graft polymerizing acrylonitrile and styrene onto a rubbery latex obtained by copolymerizing butadiene and alkyl acrylate. AABS elastic body obtained by emulsion polymerization, SB elastic body which is a particulate rubber elastic body containing 50% by weight or more of butadiene units obtained by graft polymerizing styrene to polybutadiene latex obtained by emulsion polymerization [Journal of the Japanese Society of Rheology] 124 pages, Volume 8 (1980)].

In the composition of the present invention, one type of particulate rubbery polymer as the component (d) may be used, or two or more types may be used in combination, and the content thereof is as follows: (b)
, (c) and (d), based on the total amount of components, from 8 to 30% by weight, preferably from 12 to 25% by weight. If this amount is less than 8% by weight, impact resistance will be insufficient, and if it exceeds 30% by weight, rigidity and heat resistance will decrease.

The polypropylene resin composition of the present invention includes the above (a),
It may be prepared by kneading components (b), (c) and (d) at the same time, but first pre-kneading pre-kneaded amounts of components (b), (C) and (d), and then kneading the components. It is advantageous to prepare the product by further kneading it with a predetermined amount of (a) Jffi.

To prepare the pre-mixed material, a melt mixing method using an extruder, kneader, etc. commonly used for kneading resins, or a roll mixer, Banbury mixer, etc. commonly used for rubber kneading processing can be used. Further, the final composition is obtained by uniformly tri-blending the pre-kneaded product obtained in this manner and the component (a), and then using an extruder, a kneader, etc.
It can be obtained by melt-kneading in a roll mixer, Banbury mixer, or the like.

At this time, various known additive components may be added at an appropriate time and kneaded as necessary, within a range that does not impair the purpose of the present invention. The additive components include, for example, calcium carbonate,
Talc, mica, silica, asbestos, glass peas,
Inorganic photonic agents such as glass flakes, titanium oxide, alumina, quartz powder, and metal powder; reinforcing agents such as glass fiber, carbon fiber, and metal whiskers; antioxidants; ultraviolet absorbers; heat stabilizers; nucleating agents; molding agent, lubricant, flame retardant, antistatic agent,
Additives such as colorants, as well as other thermoplastic resins, rubbers, elastomers, and the like can be mentioned.

Effects of the Invention The polypropylene resin composition of the present invention is mainly composed of a polypropylene resin and a polyphenylene ether resin, and is blended with a specific block copolymer and a particulate rubbery polymer, and has excellent solvent resistance. , has an excellent balance of heat resistance, rigidity, impact strength, and appearance, as well as good formability.
Large-sized molded products and thin-walled molded products can be easily obtained, and it is suitably used as a material for parts in various fields such as automobiles, home appliances, and OA equipment.

EXAMPLES Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way.

The properties of the composition and the average particle size of the particulate rubbery polymer were determined as follows.

(1) Approximately 3 mm x 3 mm x from a molded piece obtained by dispersion injection molding
A 3 mm cube was cut out, double stained with ruthenic acid and osmic acid, and then ultrathin sections were prepared using an ultramicrotome and observed using a TEM (transmission electron microscope). As a result, an image in which the components (C) and (d) are dyed black is observed.

(2) Measurement of bending modulus of elasticity according to JIS K7203 Annex Bending test method using small test pieces, distance between supports 50 mm, test speed 1.5 mm1
The test was carried out using an Instron testing machine at min.

For the 80°C and 120°C tests, a constant temperature bath was installed, and the test piece was left at a predetermined temperature for 30 minutes or more to reach an equilibrium state, and then the test was conducted.

(3) Izot impact test A notched Izot impact test was conducted according to JIS K7110.

(4) Measurement of fluidity According to the reference test of JIS K7210, the resin temperature was 280.
The flow value (Q value) was determined under the conditions of 160 kg at °C and a load of 160 kg. However, for polypropylene alone, 230℃,
MFR was measured under the condition of 2.16J29 load.

(5) Solvent resistance test The molded product was fixed to a jig with a constant radius of curvature that gave a bending strain of 1.5%, and soaked with pseudo gasoline (toluene/isooctane - 40/60vo 1% mixed solution). The surface of the molded product was covered with gauze, and after 15 minutes, the surface of the molded product was observed to see if there were any cracks.

If cracks did not occur, it was rated as ○, and if cracks did occur, it was rated as ×.

(6) Measurement of average particle size of particulate rubbery polymer After dispersing the particulate rubbery polymer in acetone or methanol and spraying it onto a micromesh for electron microscopic observation,
Electron microscopic observation was performed, and the average particle size was measured using the formula shown below.

However, di: particle diameter of each particle (μm) n: number of particles (
1000) In addition, the following components were used.

(a) Polypropylene resin; Homopolypropylene: manufactured by Idemitsu Petrochemical Co., Ltd., trade name E
100G (tacticity = 96%) Block polypropylene: manufactured by Idemitsu Petrochemical Co., Ltd., trade name E150G (tacticity = 96%), J785H (tacticity: mm fraction 98%) Measurement of mm fraction (1) NMR measurement sample After putting 250 mg of the prepared sample into a sample tube for NMR measurement with a diameter of 10 mm, 2.6 m12 of 1,2,4-trichlorobenzene/heavybenzene mixed solvent (volume ratio 90/10) was added, and then an aluminum tube was placed. Melt the sample at 14,000 ℃ in a block heater until it becomes uniform, and conduct NMR analysis.
Prepare the measurement sample.

(2) NMR measurement conditions Equipment: 400MHzFT-NMRC JEOL (
Co., Ltd.] Measurement temperature = 130°C Measurement method: Proton complete decoupling method MFR is JIS
Measurement was performed at 230° C. under a load of 2.16 kg in accordance with K7210, and the ethylene unit content was determined using an infrared spectrometer.

(b) Polyphenylene ether resin; Poly(2,6-dimethyl-1.4-7 dinilene) ether PO-1 Catalog No. 18178-1 manufactured by Aldrich Japan
weight average molecular weight of about 50,000, number average molecular weight of about 15
．． 000, hereinafter this resin will be referred to as PP0-1.

PP0-2 Noryl PP0534 J Manufactured by GEP Japan Co., Ltd., poly(2,6-cymethyl-1
．． 4-) Composition of ether and high impact polystyrene in a weight ratio of about 75 + 25 (weight ratio is "
(measured by C-NMR), this resin composition is referred to as PP0-2 below.
shall be.

PO-3 Aldrich Japan Catalog No. 18178-1
and polystyrene (trade name: Idemitsu Styrene GP HH3)
0) in a weight ratio of 75:25. This resin mixture is hereinafter referred to as PP0-3.

PO-4 Aldrich Japan Catalog No. 18178-1
and high impact polystyrene (trade name: Idemitsu Styrol HI HT-52) in a weight ratio of 75:25. This resin mixture is hereinafter referred to as PP0-4.

(c)A Block copolymer represented by (B-A)n or (A-B)n Table 1 shows the block copolymer represented by (B-A)n or (AB)n.

(d) Particulate rubbery polymer MBS-1: manufactured by Kureha Chemical Co., Ltd., trade name KCA201, average particle size 0.2 μm MBS-2: manufactured by Mitsubishi Rayon Co., Ltd., trade name Metablane C-223, average particle size 0 .4 μm MBS-3: Manufactured by Mitsubishi Rayon Co., Ltd., trade name Metablen C5-23 Average particle size 0.5 μm Prototype A: SB elastic body created during manufacturing, average particle size 1
．． 5 μm Prototype B: MBS elastic body prepared in Production Example 2, average particle size 0.8 μm Production Example 1 50 parts by weight of polybutadiene latex with an average particle size of 1.3 μm, 20 parts by weight of styrene, 0.1 potassium rosinate Parts by weight, 0.1 parts by weight of potassium hydroxide, 0.2 parts by weight of sodium pyrophosphate, 0.3 parts by weight of dextrose, 0.01 parts by weight of ferrous sulfate, and 150 parts by weight of water were placed in a reaction vessel equipped with a stirrer. After purging with nitrogen, the temperature was raised to 70°C, 0.2 parts by weight of cumene hydroperoxide was added as a radical polymerization catalyst, and polymerization was carried out for 1 hour.

Thereafter, a separately prepared emulsion consisting of 30 parts by weight of styrene, 1.5 parts by weight of potassium rosinate, 0.1 parts by weight of potassium hydroxide, 0.2 parts by weight of cumene hydroperoxide, and 50 parts by weight of water was applied for 3 hours. After adding it to the polymerization system, the reaction was continued for another hour while maintaining the jacket temperature at 70'C, and the polymerization was completed.

1.0 parts by weight of 2.6-di-t-butyl-p-cresol and 2.0 parts by weight of sulfuric acid are added as anti-aging agents to the rawhide latex, which is coagulated by heating, filtered, washed with water, and dried. A particulate rubbery polymer (SB elastic body) having an average particle size of 1.5 μm was obtained. This product is called prototype A.

Production example 2 Polybutadiene latex 10 with an average particle size of 0.08 μm
3 parts by weight of a copolymer latex with an average particle size of 0.08 μm consisting of 80% by weight of n-butyl acrylate units and 20% by weight of acrylic acid units and 10% by weight aqueous magnesium sulfate solution based on 0 parts by weight (in terms of solid content) 3 parts by weight was added to coagulate and enlarge the polybutadiene latex.

To 67 parts by weight of this enlarged polybutadiene latex, 50 parts by weight of distilled water, 10.2 parts by weight of Demol N [manufactured by Kao Corporation, naphthalene sulfonic acid-formalin condensate],
0.02 parts by weight of sodium hydroxide and 0 dextrose
．． Add 35 parts by weight of methyl methacrylate, raise the temperature, and at 60°C add 0.05 parts by weight of ferrous sulfate and 0.2 parts of sodium pyrophosphate; then immediately add 15 parts of methyl methacrylate and cumene hydroper. A mixed solution containing 0.2 parts by weight of oxide was added dropwise, and then a mixed solution containing 18 parts by weight of styrene and 0.2 parts by weight of cumene hydroperoxide was added dropwise. After cooling, the obtained latex was coagulated with dilute sulfuric acid,
After washing and filtering, the mixture was dried to obtain a graft polymer (MBS elastic body). The number average particle size of this graft polymer is 0.
21 p m, the area average particle size was 0.74 μm, and the volume average particle size was 0.82 μm. This product will be referred to as prototype B.

Example 1 40.3 parts by weight of polyphenylene ether, 3.3 parts by weight of the block copolymer "Toughtic H-1051J" and 816.1 parts by weight of a particulate rubbery polymer prototype were thoroughly mixed in a mixer, and then mixed with Dulmage. Using a single-screw kneading extruder with a built-in screw (manufactured by Toyo Seiki Co., Ltd.), 270
The mixture was melt-kneaded at 150 rpm to obtain a pre-kneaded product, which was then extruded into a strand and pelletized using a rotary cutter.

Next, 59.7 parts by weight of pellets of this pre-kneaded product and 40.3 parts by weight of homopolypropylene rE100G were thoroughly mixed in a mixer, and then pelletized under the same conditions as the pre-kneading process to obtain pellets made of the resin composition. I got it.

Next, the pellets made of the resin composition thus obtained were injection molded using a mini-seven injection molding machine (manufactured by Niigata Tekko Co., Ltd.) at a cylinder temperature of 240°C and a mold temperature of 45°C. (a) 64 x 12.7 x 3.2
+++++++, (b) 64 x 10 x 3.2mm,
(c) Three types of molded products measuring 100 x 10 x 2 mm were created. The molded product in (a) is used for measurement in the Izotsu impact test.
The molded product (b) was used for bending tests, and the molded product (c) was used for solvent resistance measurement.

The results are shown in Table 2.

Examples 2 to 6, Comparative Examples 1 to 6 The same procedures as in Example 1 were carried out using the types and amounts of each component shown in Table 2.

Examples 7 to 15 During injection molding, the cylinder temperature was 280°C and the mold temperature was 8°C.
0'C! The same procedure as in Example 1 was conducted except that the conditions were as follows.

The results are shown in Table 2.

Further, a transmission microscope (TEM) photograph of the structure of the composition of Example 8 is shown. In this figure, a dispersed phase of polyphenylene ether is observed in a continuous phase of polypropylene, and a particulate rubbery polymer colored black is also observed in the dispersed phase.

As can be seen from Table 2, Comparative Example 1 and Comparative Example 2 are (
When the particulate rubbery polymer of component d) is not included, or when the amount is too small, the flexural modulus is almost the same as in the example, but the impact strength is low.

Comparative example 3 is (c)I! This is a case in which the block copolymer of t, min is not included, and the impact strength is extremely low compared to the example.

Comparative Example 4 contains too much of the block copolymer of component (c) and does not contain the particulate rubbery polymer of component (d), and although the impact strength is better than that of the example, the bending elasticity is The rate is low, especially extremely low at high temperatures (120°C).

Comparative Example 5 is a case where component (d) is used alone (PPO/HIPS
-75/25 mixture), and although the flexural modulus is better than that of the examples, the impact strength is low, the fluidity is extremely low, and the solvent resistance is also poor.

Comparative Example 6 uses only polypropylene as component (a), but both the flexural modulus at high temperature (80° C.) and impact strength are lower than those of the examples.

As described above, it is clear from the examples that a composition with good rigidity (flexural modulus), high-temperature rigidity, impact strength, and fluidity can be obtained.

[Brief explanation of drawings]

The drawing is a transmission micrograph showing the structure of the composition of the present invention.

Claims (1)

[Scope of Claims] 1 (a) 30 to 60% by weight of polypropylene resin, (b) 20 to 55% by weight of polyphenylene ether resin, (c) General formula A-(B-A)_n (A in the formula Styrene polymer block, B is at least one selected from isoprene polymer block, hydrogenated butadiene polymer block, and hydrogenated isoprene polymer block, n is an integer of 1 or more) or (A-B) _n (A, B and n in the formula have the same meanings as above) 2 to 5% by weight of a block copolymer and (d) a particulate rubbery polymer with an average particle size of 0.08 to 2 μm A polypropylene resin composition comprising 8 to 30% by weight. 2. The polypropylene resin composition according to claim 1, wherein the polyphenylene ether resin as component (b) is a mixture of polyphenylene ether and polystyrene resin or a graft polymer of polyphenylene ether and polystyrene resin.