JP6916459B2 - Resin composition - Google Patents

Description

The present invention relates to resin compositions.

Conventionally, for the purpose of improving the physical characteristics of resins, polymer blends and polymer alloys in which resins having different properties are mixed to modify the properties of the resins have been actively studied. However, in such polymer blends and polymer alloys, when resins having different polarities such as polyamide resin and polyolefin resin are composited, the composite material obtained because the resins are incompatible with each other. There was a problem that the impact resistance of the resin was significantly reduced.

Further, in the fields of automobile interior parts and exterior parts, particularly high mechanical properties are required, and it is indispensable to achieve both impact resistance and rigidity (flexural modulus). However, the rigidity and the impact resistance are contradictory properties, and further, in the conventional polymer blend and polymer alloy, the physical characteristics of the resin obtained by the compounding are dominated by the physical characteristics of any of the composited resins. Because of the tendency, it was difficult to achieve both rigidity and impact resistance.

Therefore, a method of blending a compatibility agent or the like with a resin composition has been proposed for the purpose of improving the compatibility between the polyamide resin and the polyolefin resin and achieving both rigidity and impact resistance. For example, Japanese Patent Application Laid-Open No. 2005-187809 (Patent Document 1) discloses a resin composition comprising a thermoplastic resin (A) and a resin having a reactive functional group (A). In the composition, one of (A) or (B) forms a continuous phase and the other forms a dispersed phase, or both (A) and (B) form a continuous phase and average among these continuous and dispersed phases. It is described that fine particles having a particle diameter of 300 nm or less are present.

Further, Japanese Patent Application Laid-Open No. 2014-25060 (Patent Document 2) discloses a resin composition comprising a polyamide resin, a polyolefin resin, and a modified elastomer having a reactive group capable of reacting with the polyamide resin. The resin composition comprises a co-continuous phase composed of a continuous phase A composed of the polyamide resin and a continuous phase B composed of the polyolefin resin, dispersed phases a and b dispersed in each continuous phase, and the dispersed phase. It is described that it has microdisperse phases a'and b'dispersed therein.

Further, Japanese Patent Application Laid-Open No. 2011-282234 (Patent Document 3) discloses a thermoplastic resin composition containing a polyolefin resin, a polyamide resin, and a compatibilizer. Has a continuous phase, a dispersed phase dispersed in the continuous phase, and a finely dispersed phase dispersed in the dispersed phase, and the average diameter of the finely dispersed phase is 5 to 1200 nm. Is described.

Japanese Unexamined Patent Publication No. 2005-187809 Japanese Unexamined Patent Publication No. 2014-25060 Japanese Unexamined Patent Publication No. 2011-282234

As described above, conventionally, attempts have been made to make the dispersed phase finer, mainly for the purpose of improving impact resistance. However, the present inventors have found that even with such a fine dispersed phase, the effect of improving rigidity and impact resistance is still insufficient. Furthermore, the present inventors have found that when a filler is added to these resins mainly for the purpose of improving the rigidity, the impact resistance is lowered.

The present invention has been made in view of the above-mentioned problems of the prior art, and is capable of exhibiting excellent impact resistance and rigidity, and maintaining excellent impact resistance even when a filler is added. It is an object of the present invention to provide a resin composition capable of producing the same.

As a result of intensive studies to achieve the above object, the present inventors have obtained in addition to a modified elastomer having a functional group capable of binding to the polyamide resin in the composite of a polyamide resin and a polyolefin resin which are incompatible with each other. By further containing a specific unmodified elastomer which does not substantially have the functional group, a specific structure, that is, a continuous phase made of the polyamide resin and a relatively large diameter dispersed in the continuous phase. It comprises a large dispersed phase made of the polyolefin resin, a finely dispersed phase made of the polyamide resin dispersed in the dispersed phase, and a finely dispersed phase made of the unmodified elastomer, and at least a part of the modified elastomer. Has a structure existing in the continuous phase, in the finely dispersed phase made of the polyamide resin, at the interface between the continuous phase and the dispersed phase, and at the interface between the dispersed phase and the finely dispersed phase made of the polyamide resin. It has been found that a resin composition can be obtained. Further, they have found that a resin composition having such a structure can exhibit both excellent rigidity and impact resistance, and can maintain excellent impact resistance even when a filler is added. The present invention has been completed.

That is, the resin composition of the present invention is
A resin composition containing a polyamide resin, a polyolefin resin, a modified elastomer having a functional group capable of binding to the polyamide resin, and an unmodified elastomer having substantially no functional group.
The polyolefin resin is at least one selected from the group consisting of polypropylene resin and polyethylene resin.
The modified elastomer is a modified olefin-based thermoplastic elastomer.
The unmodified elastomer is a styrene-based thermoplastic elastomer.
The content of the polyamide resin is 50 to 70% by mass with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer.
The content of the polyolefin resin is 10 to 35% by mass with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer.
The content of the modified elastomer is 5 to 25% by mass with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer.
The content of the unmodified elastomer is 5 to 25% by mass with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer.
The continuous phase A made of the polyamide resin, the dispersed phase a made of the polyolefin resin dispersed in the continuous phase A, the finely dispersed phase a ₁ ′ made of the polyamide resin dispersed in the dispersed phase a, and the undeveloped phase a1'. consists modified elastomer and a finely dispersed phase a _{2 ',}
At least a portion of the modified elastomer is present in the interface of the continuous phase A, finely dispersed phase a _{1 'in} the interface between the continuous phase A and the dispersed phase a, and a dispersed phase a finely dispersed phase a _1' and ,
In the resin phase-separated cross-sectional structure observed with an electron microscope, the total cross-sectional area of the dispersed phase a having a maximum diameter of 10 μm or more (including the cross-sectional area of other phases in the dispersed phase a) is the total of all the dispersed phases a. 25% or more of the total cross-sectional area of
It is characterized by that.

The resin composition of the present invention preferably further contains a filler, and the filler preferably has an average aspect ratio of 10 or more, and is at least selected from the group consisting of carbon fibers and glass fibers. It is preferably one kind.

Further, as the resin composition of the present invention, in the resin phase separated cross-sectional structure observed with an electron microscope, the total cross-sectional area of all the dispersed phases a (including the cross-sectional areas of other phases in the dispersed phase a). However, it is preferably 20 to 80% with respect to the total cross-sectional area of the resin composition.

Further, the resin composition of the present invention, the resin phase separation sectional structure observed by an electron microscope, all other phases of the _{'cross-sectional} area of the (fine dispersion phase a _1' finely dispersed phase a ₁ Dan The total (including the area) is preferably 1 to 30% of the total cross-sectional area of the resin composition, and the cross-sectional area of all the microdisperse phases a ₂ '(others in the microdisperse phase a _2'). The total of (including the cross-sectional area of the phases) is preferably 1 to 30% with respect to the total cross-sectional area of the resin composition.

The reason why the above object is achieved by the configuration of the present invention is not always clear, but the present inventors infer as follows. That is, for example, as described in the above patent document, in a resin composition composed of three components of a compatibility agent such as a polyamide resin, a polyolefin resin, and a modified elastomer having a functional group capable of binding to the polyamide resin. , The phase made of polyolefin resin has the highest brittleness, and the same phase is destroyed. As a result, the present inventors presume that the impact resistance of the resin composition may not be sufficiently improved. On the other hand, the resin composition of the present invention contains a specific unmodified elastomer compatible with the polyolefin resin as a fourth component in addition to the polyamide resin, the polyolefin resin and the modified elastomer. In the continuous phase made of polyamide resin, a dispersed phase having a relatively large diameter (the maximum diameter is 10 μm or more in the resin phase separated cross-sectional structure observed by an electron microscope) as a dispersed phase made of a polyolefin resin is provided. It has a structure in which at least one of the dispersed phases further includes a finely dispersed phase made of the polyamide resin and a finely dispersed phase made of the unmodified elastomer. As a result, in the resin composition of the present invention, since the brittleness of the phase made of the polyolefin resin is improved by these finely dispersed phases, the impact resistance is sufficiently improved, and both excellent impact resistance and rigidity are obtained. The present inventors presume that it can be exerted and that excellent impact resistance can be maintained even if a filler is added.

According to the present invention, it is possible to provide a resin composition capable of exhibiting excellent impact resistance and rigidity and maintaining excellent impact resistance even when a filler is added. ..

It is a schematic cross-sectional view which shows one preferable embodiment of the resin composition of this invention. 5 is a field emission scanning electron micrograph (FE-SEM photograph) after oxygen plasma treatment was applied to the frozen fracture surface of the test piece for measuring physical properties obtained in Example 1. FIG. 2 is a field emission scanning electron micrograph (FE-SEM photograph) in which a reference numeral indicating each phase is attached to the photograph shown in FIG. 5 is a field emission scanning electron micrograph (FE-SEM photograph) after oxygen plasma treatment was applied to the frozen fracture surface of the test piece for measuring physical properties obtained in Comparative Example 1. 3 is a field emission scanning electron micrograph (FE-SEM photograph) after oxygen plasma treatment was applied to the frozen fracture surface of the test piece for measuring physical properties obtained in Comparative Example 2. 3 is a field emission scanning electron micrograph (FE-SEM photograph) after oxygen plasma treatment was applied to the frozen fracture surface of the test piece for measuring physical properties obtained in Comparative Example 3.

Hereinafter, the present invention will be described in detail according to the preferred embodiment thereof. The resin composition of the present invention is a resin composition containing a polyamide resin, a polyolefin resin, a modified elastomer having a functional group capable of binding to the polyamide resin, and an unmodified elastomer having substantially no functional group.

<Polyamide resin>
Polyamide resin according to the present invention, through the amide bond (-NH-CO-) is a polymer in which a plurality of monomers, which are polymerized, in the resin composition of the present invention, the continuous phase A and finely dispersed phase a ₁ It is a resin that forms'.

Examples of the monomer constituting the polyamide resin include amino acids, lactams, diamines and dicarboxylic acids. Examples of the amino acid include 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, paraaminomethylbenzoic acid and the like, and examples of the lactam include ε-caprolactam, undecanlactam, ω-lauryl lactam and the like. Be done. Examples of the diamine include ethylene diamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, and 1,9-diaminononane. 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,13-diaminotridecane, 1,14-diaminotetradecane, 1,15-diaminopentadecan, 1,16-diaminohexadecane , 1,17-diaminoheptadecane, 1,18-diaminooctadecane, 1,19-diaminononadecan, 1,20-diaminoeikosan, 2-methyl-1,5-diaminopentane, 2-methyl-1,8 An aliphatic diamine such as −diaminooctane; an alicyclic diamine such as cyclohexanediamine and bis- (4-aminocyclohexyl) methane; an aromatic diamine such as xylylene diamine, p-phenylenediamine and m-phenylenediamine can be mentioned. .. Further, examples of the dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelli acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brushphosphoric acid, and tetradecanedioic acid. Examples thereof include aliphatic dicarboxylic acids such as pentadecanedioic acid and octadecanedioic acid; alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid; aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid. As these monomers, one type may be used alone, or two or more types may be used in combination.

Examples of such a polyamide resin include polyamide 11 (PA11), polyamide 6 (PA6), polyamide 66 (PA66), polyamide 610 (PA610), polyamide 612 (PA612), polyamide 12 (PA12), and polyamide 6T (PA6T). Polyamide 6I, Polyamide 9T, Polyamide M5T, Polyamide 1010 (PA1010), Polyamide 1012 (PA1012), Polyamide 10T, Polyamide MXD6, Polyamide 6T / 66, Polyamide 6T / 6I, Polyamide 6T / 6I / 66, Polyamide 6T / 2M-5T , Polyamide 9T / 2M-8T and the like, and one of these may be used alone or in combination of two or more.

Among these, the polyamide resin according to the present invention is preferably at least one of PA11, PA12, PA6, PA66, PA610, PA1010 and PA1012, and more preferably PA11.

In the present invention, PA11 is a polyamide resin obtained by polymerizing a monomer having 11 carbon atoms as the monomer, and is a resin containing an amide bond-containing unit having 11 carbon atoms in the main chain. As the monomer having 11 carbon atoms, 11-aminoundecanoic acid and undecanthum lactam are preferable. Among them, in the polyamide resin obtained by homopolymerizing 11-aminoundecanoic acid as a monomer, the 11-aminoundecanoic acid is derived from castor oil. Since it is a obtained compound, it is desirable from the viewpoint of environmental protection (particularly from the viewpoint of carbon neutrality). Further, PA11 contains a structural unit derived from a monomer having less than 11 carbon atoms, a structural unit derived from a monomer having 12 or more carbon atoms, and other structural units alone or in combination of two or more. However, the content of the structural unit derived from the monomer having 11 carbon atoms is preferably 50 mol% or more, preferably 100 mol% or more of all the structural units in PA11. Is more preferable.

Further, in the present invention, PA6 is a homopolymer of ε-caprolactam among the monomers having 6 carbon atoms, and PA66 is a copolymer of hexamethylenediamine and adipic acid, and PA6T and PA6T. Is a copolymer of hexamethylenediamine and terephthalic acid.

The weight average molecular weight of the polyamide resin according to the present invention is not particularly limited, but is preferably 5,000 to 100,000 in terms of weight average molecular weight (in terms of polystyrene) by gel permeation chromatography (GPC). It is more preferably 7,500 to 70,000, and even more preferably 10,000 to 50,000.

The content of the polyamide resin according to the present invention is preferably 50 to 70% by mass, preferably 55 to 65% by mass, based on the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer. Is more preferable. When the content is less than the lower limit, a continuous phase made of the polyolefin resin tends to be formed, while when the content exceeds the upper limit, the maximum diameter of the dispersed phase a made of the polyolefin resin becomes smaller. There is a tendency.

<Polyolefin resin>
The polyolefin resin according to the present invention is a resin that forms the dispersed phase a in the resin composition of the present invention.

The polyolefin resin is not particularly limited, and various polyolefins can be used. For example, an ethylene homopolymer (polyethylene), a propylene homopolymer (polypropylene), an ethylene-propylene copolymer, and an ethylene- Examples thereof include α-olefin copolymers and propylene-α-olefin copolymers. The α-olefin is usually an unsaturated hydrocarbon compound having 3 to 20 carbon atoms, and is, for example, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 3-methyl-1-butene. , 4-Methyl-1-pentene and the like.

As such a polyolefin resin, one type may be used alone, or two or more types may be used in combination, and among them, it is derived from propylene from the viewpoint that the rigidity of the resin composition tends to be further improved. A polypropylene resin having a constituent unit as a main constituent unit and / or a polyethylene resin having a constituent unit derived from ethylene as a main constituent unit is preferable, and a polypropylene resin is more preferable. Further, as such a polypropylene resin and a polyethylene resin, the content of the structural units derived from propylene or ethylene is preferably 50 mol% or more of all the structural units in the polypropylene resin or the polyethylene resin, respectively. , 100 mol% is more preferable. When the content is less than the lower limit, the rigidity of the resin composition tends to decrease.

The weight average molecular weight of the polyolefin resin according to the present invention is not particularly limited, but is 10,000 to 500,000 in terms of weight average molecular weight (standard polystyrene equivalent, temperature: 140 to 150 ° C.) by gel permeation chromatography (GPC). It is preferably 50,000 to 450,000, more preferably 100,000 to 400,000.

The content of the polyolefin resin according to the present invention is preferably 10 to 35% by mass, preferably 15 to 30% by mass, based on the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer. Is more preferable. When the content is less than the lower limit, the maximum diameter of the dispersed phase a made of the polyolefin resin tends to be smaller, while when the content exceeds the upper limit, a continuous phase made of the polyolefin resin is formed. There is a tendency.

The polyolefin resin according to the present invention is different from the modified elastomer described later in that it is incompatible with the polyamide resin according to the present invention and does not substantially have a functional group capable of binding to the polyamide resin. different. Further, in the resin composition of the present invention, the unmodified elastomer that does not substantially have the functional group described later needs to be an elastomer other than the polyolefin resin according to the present invention. In the present invention, the resin or elastomer "substantially having no functional group capable of binding to the polyamide resin" means that the ratio of the functional group in the resin or elastomer is 0.1% by mass or less. It means that it is preferably 0% by mass.

<Modified elastomer>
The modified elastomer according to the present invention is an elastomer having a functional group capable of binding to the polyamide resin, and functions as a compatibilizer for making the polyamide resin and the polyolefin resin compatible in the resin composition of the present invention. do.

In the resin composition of the present invention, the modified elastomer needs to be at least one selected from the group consisting of modified olefin-based thermoplastic elastomers and modified styrene-based thermoplastic elastomers. The modified olefin-based thermoplastic elastomer is an olefin-based thermoplastic elastomer having the functional group, and the modified styrene-based thermoplastic elastomer is a styrene-based thermoplastic elastomer having the functional group.

Examples of the olefin-based thermoplastic elastomer include copolymers of two or more monomers of α-olefins such as ethylene, propylene, 1-butene, 1-pentene, and 1-octene. One of the copolymers may be used alone or two or more thereof may be used in combination. Among them, as the olefin-based thermoplastic elastomer, a copolymer of ethylene or propylene and an α-olefin having 3 to 8 carbon atoms, from the viewpoint that the rigidity and impact resistance of the resin composition tend to be further improved. That is, it is preferably at least one of a copolymer of ethylene and an α-olefin having 3 to 8 carbon atoms and a copolymer of propylene and an α-olefin having 4 to 8 carbon atoms. More specifically, such olefin-based thermoplastic elastomers include, for example, ethylene-propylene copolymer (EPR), ethylene-1-butene copolymer (EBR), ethylene-1-pentene copolymer, and ethylene. Examples thereof include -1-octene copolymer (EOR), propylene-1-butene copolymer (PBR), propylene-1-pentene copolymer and propylene-1-octene copolymer (POR).

Examples of the styrene-based thermoplastic elastomer include a block copolymer of a styrene-based compound and a conjugated diene compound or the α-olefin, and a hydrogenated product thereof, and even if one of these is used alone, 2 You may use a combination of seeds or more. Examples of the styrene-based compound include styrene; alkylstyrene such as α-methylstyrene, p-methylstyrene, and pt-butylstyrene; p-methoxystyrene; and vinylnaphthalene. Examples of the conjugated diene compound include butadiene, isoprene, piperylene, methylpentadiene, phenylbutadiene, 3,4-dimethyl-1,3-hexadiene, and 4,5-diethyl-1,3-octadien. Be done. More specifically, such styrene-based thermoplastic elastomers include, for example, styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), and styrene-ethylene / butylene-styrene. Examples include polymer (SEBS) and styrene-ethylene / propylene-styrene copolymer (SEPS).

Further, as the functional group that can be bonded to the polyamide resin, a functional group that can be covalently bonded to the polyamide resin, more specifically, for example, an acid anhydride group (-CO-O-OC-), a carboxyl group ( -COOH), epoxy group [-C ₂ O (three-membered ring structure consisting of two carbon atoms and one oxygen atom)], oxazoline group (-C ₃ H ₄ NO), isocyanate group (-NCO). Be done. Among these, an acid anhydride group is preferable as the functional group from the viewpoint that the reactivity tends to be high.

Further, the method for imparting the functional group to the olefin-based thermoplastic elastomer and the styrene-based thermoplastic elastomer is not particularly limited, and a known method can be appropriately used. For example, as a method of imparting the acid anhydride group to the elastomer, a method of further adding an acid anhydride as a monomer of the elastomer can be mentioned, and examples of the acid anhydride include maleic anhydride, phthalic anhydride, and anhydrous. Examples thereof include itaconic acid, succinic anhydride, glutaric anhydride, adipic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, and succinic anhydride. As the acid anhydride, one type may be used alone or two or more types may be used in combination. Among them, maleic anhydride, phthalic anhydride, and itaconic anhydride from the viewpoint of high reactivity. Is preferable, and maleic anhydride is more preferable.

Specific examples of the modified elastomer according to the present invention include maleic anhydride-modified EPR, maleic anhydride-modified PBR, maleic anhydride-modified EBR, maleic anhydride-modified EOR, and maleic anhydride-modified POR. Hydroplastic elastomers; Examples thereof include maleic anhydride-modified styrene-based thermoplastic elastomers such as maleic anhydride-modified SEBS, maleic anhydride-modified SBS, maleic anhydride-modified SIS, and maleic anhydride-modified SEPS. As such a modified elastomer, one type may be used alone or two or more types may be used in combination. Further, in the modified elastomer according to the present invention, the ratio of the functional groups is preferably 0.5% by mass or more, and more preferably 0.5 to 5% by mass.

Among these, the modified elastomer according to the present invention is preferably a modified olefin-based thermoplastic elastomer, which has high reactivity, is more compatible with the polyolefin resin, and has rigidity and impact resistance of the resin composition. From the viewpoint that it tends to be further improved, it is more preferable that it is at least one of maleic anhydride-modified PBR, maleic anhydride-modified EBR, and maleic anhydride-modified EOR.

The weight average molecular weight of the modified elastomer according to the present invention is not particularly limited, but gel permeation chromatography (from the viewpoint that the larger the weight average molecular weight, the better the impact resistance of the resin composition tends to be. The weight average molecular weight (standard polystyrene equivalent, temperature: 140 to 150 ° C.) according to GPC) is preferably 10,000 to 500,000, more preferably 20,000 to 500,000, and 25,000. It is more preferably ~ 400,000.

The content of the modified elastomer according to the present invention is preferably 5 to 25% by mass, preferably 5 to 20% by mass, based on the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer. Is more preferable. When the content is less than the lower limit, the resin composition tends not to exhibit sufficient impact resistance, while when the content exceeds the upper limit, the resin composition tends not to exhibit sufficient rigidity. It is in.

<Unmodified elastomer>
The unmodified elastomer according to the present invention refers to a substantially no elastomer functional group capable of binding with the polyamide resin, the resin composition of the present invention, a resin for forming a finely dispersed phase a _{2 '} be.

In the resin composition of the present invention, the unmodified elastomer needs to be at least one selected from the group consisting of olefin-based thermoplastic elastomers and styrene-based thermoplastic elastomers. Examples of the olefin-based thermoplastic elastomer and the styrene-based thermoplastic elastomer include the same ones listed as the elastomer in the modified elastomer. Among these, the elastomers contained in the resin composition of the present invention are EPR, EBR, EOR, PBR, POR, SBS, SIS, SEBS and SEPS from the viewpoint of being easily compatible with the polyolefin resin. It is preferably at least one of them, and more preferably at least one of EPR, EBR, EOR and SEBS.

The unmodified elastomer according to the present invention is different from the modified elastomer in that it does not substantially have the functional group. Further, in the resin composition of the present invention, the unmodified elastomer needs to be an elastomer other than the polyolefin resin. Therefore, in the resin composition of the present invention, an unmodified elastomer to be contained is selected from the elastomers according to the type of the polyolefin resin.

The weight average molecular weight of the unmodified elastomer according to the present invention is not particularly limited, but the weight average molecular weight (standard polystyrene equivalent, temperature: 140 to 150 ° C.) by gel permeation chromatography (GPC) is 5,000 to 1, It is preferably 1,000,000, more preferably 10,000 to 700,000, and even more preferably 10,000 to 500,000.

The content of the unmodified elastomer according to the present invention is preferably 5 to 25% by mass, preferably 5 to 20% by mass, based on the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer. More preferably. When the content is less than the lower limit, the resin composition tends not to exhibit sufficient impact resistance, while when the content exceeds the upper limit, the resin composition tends not to exhibit sufficient rigidity. It is in.

<Other ingredients>
The resin composition of the present invention preferably further contains a filler from the viewpoint that the rigidity tends to be further improved. The resin composition of the present invention can exhibit excellent impact resistance even if it contains a filler.

Examples of the filler include inorganic fibers (glass fibers, alumina fibers, carbon fibers (carbon fibers), potassium titanate fibers, etc.); organic fibers (aromatic polyester fibers, aromatic polyamide fibers, fluororesin fibers, polyimide cones, plants). (Sex fiber, etc.); Glass, silica, graphite, silicate compounds (calcium silicate, aluminum silicate, kaolin, talc, clay, etc.), metal oxides (iron oxide, titanium oxide, zinc oxide, antimony oxide, alumina, etc.), metal carbonate Examples thereof include particles and flakes composed of salts or sulfates (carbonates or sulfates such as calcium, magnesium, zinc), etc., and one of these may be used alone, or two or more thereof may be used in combination. May be good. Above all, the filler is more preferably at least one of carbon fiber and glass fiber.

Further, as the filler, the average aspect ratio is preferably 10 or more, and more preferably 20 or more, from the viewpoint that the effect of improving the rigidity of the resin composition tends to be high. In the present invention, the aspect ratio means the ratio of the length in the major axis direction to the ellipse in the minor axis direction (length in the major axis direction / diameter in the minor axis direction). Further, the length in the major axis direction means the length of the longest axis, the diameter in the minor axis direction means the maximum length of the surface orthogonal to the longest axis, and the average aspect ratio is an arbitrary 100 or more. The length of the filler in the major axis direction and the diameter in the minor axis direction can be measured with an electron microscope to obtain each aspect ratio, and the values can be averaged.

When these fillers are contained in the resin composition of the present invention, the content thereof is 50% by mass or less with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer, the unmodified elastomer and the filler. It is preferably 3 to 35% by mass, and more preferably 3 to 35% by mass. When the content is less than the lower limit, the rigidity of the resin composition tends not to be sufficiently improved, while when the content exceeds the upper limit, the moldability of the resin composition tends to decrease.

Further, the resin composition of the present invention may further contain a reaction product of the polyamide resin and the modified elastomer. The reactant is a component produced by the reaction of the functional group of the modified elastomer with the polyamide resin. The method for obtaining such a reactant is not particularly limited, and in the production of the resin composition of the present invention, the resin composition of the present invention is obtained by heating, melting and kneading a mixed material containing the polyamide resin and the modified elastomer. Can be obtained inside.

When such a reactant is contained in the resin composition of the present invention, the content thereof is based on the total mass of the polyamide resin, the polyolefin resin, the modified elastomer, the unmodified elastomer and the reactant. It is preferably 35% by mass or less, and more preferably 5 to 30% by mass. When the content is less than the lower limit, sufficient impact resistance tends not to be exhibited in the resin composition, while when the content exceeds the upper limit, sufficient rigidity is exhibited in the resin composition. It tends to disappear.

Further, the resin composition of the present invention is, for example, a thermoplastic resin other than the above, an antioxidant, an anti-ultraviolet agent, and a heat stabilizer, if necessary, as long as the effect of the present invention is not impaired. , Flame retardant, flame retardant aid, colorant, antibacterial agent, antistatic agent, lubricant, mold release agent, foaming agent, etc. It may be contained. Examples of the other thermoplastic resin include polyester resins (polybutylene terephthalate, polyethylene terephthalate, polytrimethylene terephthalate, polybutylene succinate, polyethylene succinate, polylactic acid, polyhydroxyalkanoic acid), polycarbonate resins and the like. One of these may be used alone or two or more thereof may be used in combination. Examples of the flame retardant include halogen-based flame retardants (halogenated aromatic compounds, etc.), phosphorus-based flame retardants (nitrogen-containing phosphate compounds, phosphate esters, etc.), nitrogen-based flame retardants (guanidine, triazine, melamine, and the like). , Inorganic flame retardants (metal hydroxides, etc.), boron flame retardants, silicone flame retardants, sulfur flame retardants, red phosphorus flame retardants, etc. It may be used in combination or a combination of two or more. Examples of the flame retardant aid include various antimony compounds, metal compounds containing zinc, metal compounds containing bismuth, magnesium hydroxide, viscous silicates, and the like, and even if one of these is used alone, 2 You may use a combination of seeds or more. Examples of the colorant include pigments and dyes, and one of them may be used alone or two or more thereof may be used in combination.

When these additives are contained in the resin composition of the present invention, the total content of these additives is preferably 10% by mass or less in the total amount of the resin composition.

<Resin composition>
Next, the structure of the resin composition of the present invention will be described in detail with reference to the drawings according to the preferred embodiment thereof. However, the present invention is not limited to this. In the following description and drawings, the same or corresponding elements are designated by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 1, the resin composition of the present invention is dispersed with a continuous phase A (10) made of the polyamide resin and a dispersed phase a (20) made of the polyolefin resin dispersed in the continuous phase A. _{A finely dispersed phase a 1} '(31) made of the polyamide resin dispersed in the phase a _{and a finely dispersed phase a 2} '(32) made of the unmodified elastomer are provided, and at least a part of the modified elastomer is contained. In the continuous phase A (41), in the finely dispersed phase a ₁ '(42), the interface between the continuous phase A and the dispersed phase a (43), and the interface between the dispersed phase a and the finely dispersed phase a ₁ '(44). In the resin phase-separated cross-sectional structure observed with an electron microscope, the cross-sectional area of the dispersed phase a having a maximum diameter of 10 μm or more (including the cross-sectional area of another phase in the dispersed phase a). ) Is 25% or more of the total cross-sectional area of all the dispersed phases a.

In the present invention, the phase structure (resin phase-separated cross-sectional structure) of the resin composition can be observed using an electron microscope, and as such an observation method, for example, a cross section of an injection-molded resin composition. After performing oxygen plasma etching treatment at 100 W for 1 minute, this cross section is subjected to an electric field radiation scanning electron microscope (FE-SEM, manufactured by Hitachi High-Tech Manufacturing & Service Co., Ltd., "S-4300 TYPE II", acceleration voltage 2 kV. ) Is used for observation.

The continuous phase A (10) according to the present invention is a phase made of the polyamide resin. In the resin composition of the present invention, in the continuous phase A (10), there is a dispersed phase a (20) composed of the polyolefin resin dispersed in the continuous phase. Further, in the continuous phase A (10), there is also a dispersed phase b (41) made of a modified elastomer dispersed in the continuous phase. Further, it is preferable that the dispersed phase c (21) made of the unmodified elastomer is further present in the continuous phase A (10), and the dispersed phase made of the reaction product of the polyamide resin and the modified elastomer (shown). ) May be present further.

The dispersed phase a (20) according to the present invention is a phase made of the polyolefin resin and dispersed in the continuous phase A (10). In the resin composition of the present invention, in the resin phase separated cross-sectional structure, the total cross-sectional area of the dispersed phase a having a maximum diameter of 10 μm or more is 25% (area%) of the total cross-sectional area of all the dispersed phases a. ) It is necessary to be above. If the proportion of the dispersed phase a having a maximum diameter of 10 μm or more is less than the lower limit, sufficient impact resistance is not exhibited. The ratio of the total cross-sectional area of the dispersed phase a having a maximum diameter of 10 μm or more to the total cross-sectional area of all the dispersed phases a is preferably 25 to 80%, preferably 25 to 70%. Is more preferable. When the ratio is less than the lower limit, sufficient rigidity tends not to be exhibited in the resin composition, while when the ratio exceeds the upper limit, it tends to be difficult to form the dispersed phase a.

Further, in the resin phase separated cross-sectional structure, the average maximum diameter of the dispersed phase a according to the present invention is preferably in the range of 0.1 to 30 μm, and preferably in the range of 0.1 to 20 μm. More preferred. When the average maximum diameter of the dispersed phase a is less than the lower limit, the resin composition tends not to exhibit sufficient rigidity, while when the average maximum diameter exceeds the upper limit, the resin composition has sufficient impact resistance. It tends not to be exhibited.

The total content of the dispersed phase a according to the present invention is the total of the cross-sectional areas of all the dispersed phases a (including the cross-sectional areas of other phases of the dispersed phase a) in the resin phase separated cross-sectional structure. However, it is preferably 20 to 80% (area%), more preferably 25 to 70%, based on the total cross-sectional area of the resin composition. When the content of the dispersed phase a is less than the lower limit, the resin composition tends not to exhibit sufficient rigidity, while when the content exceeds the upper limit, the resin composition exhibits sufficient impact resistance. It tends not to be done.

In the present invention, the cross-sectional areas of the dispersed phase and the finely dispersed phase described later include the cross-sectional areas of other phases if they are present in the phase. For example, the cross-sectional area of the dispersed phase a includes the cross-sectional area of other phases (micro-dispersed phase, ultra-fine dispersed phase, etc.) other than the same dispersed phase a in the dispersed phase a.

Further, in the present invention, the maximum diameter of the dispersed phase and the finely dispersed phase described later means the longest diameter (length in the major axis direction) when the cross section of the phase is circular, and the phase. If the cross section of is not circular, it means the diameter of the circumscribed circle. Further, in the present invention, the average maximum diameter of the dispersed phase and the finely dispersed phase described later is 30 μm or more that does not overlap with each other at 10 (N) points observed by the electric field radiation scanning electron microscope (FE-SEM). In each minute range of 40 μm or more (more preferably 30 μm × 40 μm to 40 μm × 50 μm), the maximum diameters of all the observed dispersed phases (or all microdispersed phases) were measured, and all the measured values at N points were measured. The average value.

Further, in the present invention, the ratio of the total cross-sectional area of the dispersed phase a having a maximum diameter of 10 μm or more to the total cross-sectional area of all the dispersed phases a (hereinafter, sometimes referred to as “coarse dispersed phase ratio”). Is observed in the electric field radiation type scanning electron microscope (FE-SEM) in each minute range of 30 μm or more × 40 μm or more (more preferably 30 μm × 40 μm to 40 μm × 50 μm) which does not overlap with each other at 10 (N) points. , The cross-sectional area and the maximum diameter of all the observed dispersed phases a are measured to obtain the coarse dispersed phase ratio (n) within the range, and the average of the coarse dispersed phase ratios (n) at N points. To say.

Further, in the present invention, the ratio of the total cross-sectional area of all dispersed phases (or all finely dispersed phases) to the total cross-sectional area of the resin composition (hereinafter, in some cases, "dispersed phase (or all finely dispersed phases)). The total content (referred to as "total content") is 30 μm or more × 40 μm or more (more preferably 30 μm × 40 μm to 40 μm × In each minute range of 50 μm), the cross-sectional area of all observed dispersed phases (or all finely dispersed phases) is measured, and the total content (n) of the dispersed phases (or all finely dispersed phases) within that range is measured. ) Is obtained, and the value obtained by averaging the total content (n) at N locations.

In at least one of the dispersed phases a (20) according to the present invention, the finely dispersed phase a ₁ '(31) made of the polyamide resin and the fine dispersion made of the unmodified elastomer dispersed in the dispersed phase. Phase a ₂ '(32) exists. The finely dispersed phase a ₁ '(31) and the finely dispersed phase a ₂ '(32) need only be present in at least one of the dispersed phases a (20), and the finely dispersed phase a ₁ '(31). ) And the finely dispersed phase a ₂ '(32) may be dispersed in different dispersed phases a (20). Further, in the dispersed phase a (20), a finely dispersed phase (not shown) composed of a modified elastomer dispersed in the dispersed phase and / or a fine dispersion composed of a reaction product of the polyamide resin and the modified elastomer. Phases (not shown) may be present.

_{The finely dispersed phase a 1} '(31) according to the present invention is a phase made of the polyamide resin and dispersed in the dispersed phase a (20). In the resin composition of the present invention, _{in at least one of the finely dispersed phases a 1} '(31), an ultrafine dispersed phase a'' (42) composed of a modified elastomer dispersed in the finely dispersed phase. There are more. Further, in the finely dispersed phase a ₁ '(31), an ultrafinely dispersed phase (not shown) composed of a reaction product of the polyamide resin and the modified elastomer may be further present.

_{The finely dispersed phase a 2} '(32) according to the present invention is a phase made of the unmodified elastomer and dispersed in the dispersed phase a (20). In the resin composition of the present invention, the finely dispersed phase a ₂ '(32) within the ultra finely dispersed phase consisting of dispersed modified elastomer fine dispersed phase in (not shown) and / or the polyamide resin An ultrafine dispersed phase (not shown) composed of a reaction product of the modified elastomer and the modified elastomer may be further present.

As the average maximum diameter of the finely dispersed phase a ₁ '(31) and the finely dispersed phase a ₂ '(32) according to the present invention, the average maximum diameter measured in the resin phase separated cross-sectional structure is 0. It is preferably in the range of 01 to 5 μm, and more preferably in the range of 0.05 to 3 μm. The method of obtaining the average maximum diameter of the finely dispersed phase a ₁ '(31) and the finely dispersed phase a _{2'(32) is as described above.}

The total content of the finely dispersed phase a ₁ '(31) according to the present invention is the cross-sectional area of _{all the finely dispersed phases a 1 '(inside the finely dispersed phase a 1} '" in the resin phase separated cross-sectional structure. The total (including the cross-sectional areas of the other phases) is preferably 1 to 30% (area%), more preferably 3 to 25%, based on the total cross-sectional area of the resin composition. When the content is less than the lower limit, the resin composition tends not to exhibit sufficient impact resistance, while when the content exceeds the upper limit, the resin composition tends not to exhibit sufficient rigidity. It is in. Note that the entire content of Determination of the finely dispersed phase a _{1 'are} as defined above.

Further, 'The total content of (32), in the resin phase separation structure at cross section all finely dispersed phase a _2' finely dispersed phase a ₂ according to the present invention the cross-sectional area (fine dispersed phase a _{2 'in} the The total (including the cross-sectional areas of the other phases) is preferably 1 to 30% (area%), more preferably 3 to 25%, based on the total cross-sectional area of the resin composition. When the content is less than the lower limit, the resin composition tends not to exhibit sufficient impact resistance, while when the content exceeds the upper limit, the resin composition tends not to exhibit sufficient rigidity. It is in. Note that the entire content of Determination of the finely dispersed phase a _{2 'are} as defined above.

In the resin composition of the present invention, at least a part of the modified elastomer is in the continuous phase A (41), in the finely dispersed phase a ₁ '(42), and the interface between the continuous phase A and the dispersed phase a (43). , And at the interface (44) between the dispersed phase a and the finely dispersed phase a _1'. When the dispersed phase c (21) made of the unmodified elastomer is further present, the modified elastomer is preferably further present at the interface (45) between the continuous phase A and the dispersed phase c. When the modified elastomer is present in the continuous phase A (10), it exists as the dispersed phase b (41) composed of the modified elastomer, and when it is present in the finely dispersed phase a ₁ '(31), it is present. , Exists as an ultrafine dispersion phase a'' (42) composed of the above-mentioned modified elastomer. Further, when it exists at the interface (43) between the continuous phase A and the dispersed phase a or _{the interface (44) between the dispersed phase a and the finely dispersed phase a 1} ', or the interface between the continuous phase A and the dispersed phase c ( If it is further present in 45), it may be present on at least a part of each of these interfaces, but it is more preferable that it is present on the entire surface of the interface.

In the resin composition of the present invention, when the resin composition further contains the filler, the phase in which the filler is present is not particularly limited, and the continuous phase A (10), the dispersed phase a (20), and the fine dispersion are finely dispersed. Phase a ₁ '(31), microdisperse phase a ₂ '(32), phase composed of the modified elastomer (in continuous phase A, in microdisperse phase a ₁ ', interface between continuous phase A and dispersed phase a, dispersion It may be present in any one of (the interface between the phase a and the finely dispersed phase a ₁ ') and the other phase, or in any of two or more phases.

<Manufacturing method of resin composition>
Next, a method for producing the resin composition of the present invention will be described. The resin composition of the present invention can be obtained by mixing the polyamide resin, the polyolefin resin, the modified elastomer, the unmodified elastomer, and if necessary, other components. The mixing method is not particularly limited, but a method in which the polyamide resin and the modified elastomer are mixed in advance and then the polyolefin resin and the unmodified elastomer are added is preferable.

Examples of such a mixing method include a kneading method using a kneading device. Examples of the kneading device include an extruder (single-screw extruder, twin-screw melt-kneading extruder, etc.), a kneader, and a mixer (high-speed flow mixer, paddle mixer, ribbon mixer, etc.), and one of them. May be used alone or in combination of two or more. Further, in the case where two or more kinds are used in combination, continuous operation may be performed, or batch operation may be performed. Further, the polyamide resin, the polyolefin resin, the modified elastomer, the unmodified elastomer, and if necessary, other components may be kneaded together, or any one or two or more thereof may be kneaded a plurality of times. It may be added and added separately (multi-stage blending) and kneaded.

The kneading temperature is not particularly limited and is appropriately adjusted depending on the type of resin to be mixed. Therefore, it cannot be said unconditionally, but each resin according to the present invention may be mixed in a molten state. From the viewpoint of being able to do so, the temperature is preferably 100 to 350 ° C, more preferably 180 to 320 ° C, and even more preferably 200 to 300 ° C.

Further, as a method for producing a resin composition of the present invention, first, a mixture of the polyamide resin and the modified elastomer is obtained as a solid and / or a melt, and this is melt-kneaded with the polyolefin resin and the unmodified elastomer. Alternatively, the polyamide resin and the modified elastomer may be mixed or melt-kneaded on the upstream side using a multi-stage compounding type kneading device or the like, and then the polyolefin resin and the unmodified elastomer may be added on the downstream side. The resin composition may be obtained by melt-kneading.

In the method for producing a resin composition of the present invention, the amount of the polyamide resin charged is 50 to 70 mass with respect to the total mass of the amount of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer. %, More preferably 55 to 65% by mass. When the amount of the polyamide resin charged is less than the lower limit, a continuous phase made of the polyolefin resin tends to be formed, while when the amount exceeds the upper limit, the maximum diameter of the dispersed phase a made of the polyolefin resin a. Tends to be smaller. In the production method, since the polyamide resin and the modified elastomer can produce a reactant, the charged amount of the polyamide resin and the content in the obtained resin composition do not always match.

Further, in the method for producing a resin composition of the present invention, the amount of the polyolefin resin charged is 10 to 10 with respect to the total mass of the amounts of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer. It is preferably 35% by mass, more preferably 15 to 30% by mass. Further, it is preferably 0.1 to 0.7 parts by mass, more preferably 0.2 to 0.6 parts by mass, based on 1 part by mass of the amount of the polyamide resin charged. When the amount of the polyolefin resin charged is less than the lower limit, the maximum diameter of the dispersed phase a made of the polyolefin resin tends to be smaller, while when it exceeds the upper limit, the continuous phase made of the polyolefin resin tends to be smaller. It tends to be formed.

Further, in the method for producing the resin composition of the present invention, the amount of the modified elastomer charged is 5 to 5 with respect to the total mass of the amount of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer charged. It is preferably 25% by mass, more preferably 5 to 20% by mass. Further, it is preferably 0.07 to 0.5 parts by mass, and more preferably 0.07 to 0.4 parts by mass with respect to 1 part by mass of the amount of the polyamide resin charged. If the amount of the modified elastomer charged is less than the lower limit, the resin composition tends not to exhibit sufficient impact resistance, while if it exceeds the upper limit, the resin composition exhibits sufficient rigidity. It tends not to be done. In the production method, since the polyamide resin and the modified elastomer can produce a reactant, the charged amount of the modified elastomer and the content in the obtained resin composition do not always match.

Further, in the method for producing the resin composition of the present invention, the amount of the unmodified elastomer charged is 5 with respect to the total mass of the amount of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer charged. It is preferably ~ 25% by mass, and more preferably 5 to 20% by mass. Further, it is preferably 0.07 to 0.5 parts by mass, and more preferably 0.07 to 0.4 parts by mass with respect to 1 part by mass of the amount of the polyamide resin charged. If the amount of the unmodified elastomer charged is less than the lower limit, the resin composition tends not to exhibit sufficient impact resistance, while if it exceeds the upper limit, the resin composition has sufficient rigidity. It tends not to be exhibited.

By such a production method, the resin composition of the present invention can be efficiently and surely obtained. The obtained resin composition may be a solid product solidified by pelletization or the like, or may be a melt product.

<Molded body>
The resin composition of the present invention may be formed in any way, and the method is not particularly limited. Further, the shape, size, thickness, etc. of the obtained molded product are not particularly limited, and its use is not particularly limited. For example, the molded body can be used as an exterior material, an interior material, a structural material, or the like for automobiles, railroad vehicles, ships, airplanes, and the like. The automobile materials include automobile exterior materials, automobile interior materials, automobile structural materials, automobile impact energy absorbers, automobile pedestrian protective materials, automobile occupant protective materials, engine room parts, and the like. Specifically, for example, shock absorbing parts, bumpers, spoilers, cowlings, front grilles, garnishes, bonnets, trunk lids, fender panels, door panels, roof panels, instrument panels, door trims, quarter trims, roofs. Lining, pillar garnish, deck trim, tonoboard, package tray, dashboard, console box, kicking plate, switch base, seat backboard, seat frame, armrest, sun visor, intake manifold, engine head cover, engine undercover, oil filter housing, Examples include housings for air filter boxes and in-vehicle electronic parts (ECU, TV monitors, etc.).

Further, the molded body includes, for example, interior materials such as buildings and furniture, exterior materials and structural materials, specifically, for example, door covering materials, door structural materials, various furniture (desks, chairs, shelves, chests of drawers, etc.). ) Can also be used as a surface material, structural material, etc., as well as packaging, housing (tray, etc.), protective members, partition members, home appliances (thin TVs, refrigerators, washing machines, vacuum cleaners, mobile phones). , Portable game machines, notebook computers, etc.) and bags (suitcases, etc.) can also be used as housings and structures.

Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples, but the present invention is not limited to the following Examples. The physical property evaluation and morphology observation of the resin compositions obtained in each Example and Comparative Example were carried out by the methods shown below.

<Evaluation of physical properties of resin composition>
(Measurement of Charpy impact strength)
^{The Charpy impact strength [kJ / m 2} ] was measured according to JIS K7111-1 using the test pieces for measuring physical properties obtained in each Example and Comparative Example. The measurement was performed under the conditions of temperature: 23 ° C., striking direction: edgewise, and notch type: A.

(Measurement of flexural modulus)
The flexural modulus [MPa] was measured according to JIS K7171 using the test pieces for measuring physical properties obtained in each Example and Comparative Example. The measurement is performed at a speed of 2 mm / min from the point of action (radius of curvature: 5 mm) arranged at the center between the fulcrums while supporting the two fulcrums (radius of curvature: 5 mm) with the distance (L) between the fulcrums as 64 mm. A load was applied.

(comprehensive evaluation)
From the Charpy impact strength and flexural modulus measured above, the following equation:
Comprehensive evaluation = (Charpy impact strength [kJ / m ² ]) × (flexural modulus [MPa]) ÷ 1000
The value of the comprehensive evaluation was calculated by. The value of the comprehensive evaluation is compared between the resin compositions containing no filler or the resin composition containing the filler of the same material, and the larger the value, the better the impact resistance and the excellent rigidity. It is evaluated that it can be exhibited in a well-balanced manner.

<Morphology observation>
First, oxygen plasma etching is performed at 100 W for 1 minute using a plasma reactor (manufactured by Yamato Scientific Co., Ltd., "PR300") on the frozen fracture surface of the test piece for measuring physical properties used for the measurement of the Charpy impact strength. Processed. Next, the fracture surface was subjected to an osmium coating treatment for 5 seconds using an osmium coater (manufactured by Vacuum Device Co., Ltd., “HPC-1S”). Next, the fracture surface was observed using a field emission scanning electron microscope (FE-SEM, manufactured by Hitachi High-Tech Manufacturing & Service Co., Ltd., "S-4300 TYPE II") under the condition of an acceleration voltage of 2 kV.

Further, in the obtained image (FE-SEM photograph) in the range of 30 μm × 40 μm, a dispersed phase (dispersed phase a) made of a polyolefin resin was used using image analysis software (“A image-kun” manufactured by Asahi Kasei Engineering Co., Ltd.). Measure the cross-sectional area and maximum diameter of
Coarse dispersed phase ratio (n) [%] = (total cross-sectional area of dispersed phase a having a maximum diameter of 10 μm or more ÷ total cross-sectional area of all dispersed phases a) × 100
The coarse dispersed phase ratio (n), that is, the ratio of the total cross-sectional area of the dispersed phase a having a maximum diameter of 10 μm or more to the total cross-sectional area of all the dispersed phases a was determined. Similarly, the coarse dispersion phase ratio (n) in the range of 30 μm × 40 μm at any 10 (N) locations that do not overlap each other was obtained, and the average value of those N locations was calculated to obtain the coarse dispersion phase ratio [%]. .. The maximum diameter was the longest diameter of the cross section of each dispersed phase, and when the cross section was not circular, it was the diameter of the circumscribed circle of the cross section.

(Example 1)
First, polyamide 11 (PA11, manufactured by Alchema Co., Ltd., "Lilsan BMNO", weight average molecular weight: 18,000) was used as the polyamide resin, and polypropylene (PP, manufactured by Nippon Polypro Co., Ltd., "Novatec MA1B", weight average) was used as the polyolefin resin. Molecular weight: 312,000), maleic anhydride-modified ethylene-1-butene copolymer (m-EBR, manufactured by Mitsui Kagaku Co., Ltd., "Toughmer MH7020") as a modified elastomer, and styrene-ethylene / butylene as an unmodified elastomer. -A styrene elastomer (SEBS-1, manufactured by JSR Corporation, "Dynaron 8601P") is used, and the mass ratio (PA11 mass: PP mass: m-EBR mass: SEBS-1 mass) is 60:25. A resin mixture was obtained by melt-kneading so as to have a ratio of: 10: 5. The melt-kneading is performed using a twin-screw melt-kneading extruder (manufactured by Nippon Steel Co., Ltd., "TEX30 77BW-20V") having a screw diameter of 30 mm and L / D: 77, at a temperature of 200 ° C. and an extrusion speed of 10 kg. Performed under the conditions of / hour and screw rotation speed: 200 rpm, PA11 and m-EBR were charged from the part where the residence time was the longest in the twin-screw melt-kneading extruder, and PP and SEBS-1 were charged using a side feeder. It was charged from the middle of the twin-screw melt-kneading extruder.

Next, using an injection molding machine (manufactured by Nissei Resin Industry Co., Ltd., "NEX1000-9E"), the resin composition obtained under injection conditions of a set temperature of 200 ° C. and a mold temperature of 30 ° C. was injection-molded. A multipurpose test piece specified in JIS K7139 was prepared, and this was used as a test piece for measuring physical properties.

The physical characteristics of the resin composition were evaluated using the obtained test piece for measuring physical characteristics. The obtained results are shown in Table 1 together with the blending ratio (mass ratio) at the time of charging the resin composition. In addition, morphology observation was carried out using a test piece for measuring physical properties used for measuring the Charpy impact strength. FIG. 2 shows a field emission scanning electron micrograph (FE-SEM photograph) after applying oxygen plasma treatment to the frozen fracture surface of the obtained test piece for measuring physical properties. Further, FIG. 3 shows an FE-SEM photograph in which a reference numeral corresponding to FIG. 1 is added to the FE-SEM photograph shown in FIG. Further, the coarse dispersion phase ratio obtained in Example 1 is also shown in Table 1.

(Comparative Examples 1 to 3)
In the production of the resin composition, each test piece for measuring physical characteristics was prepared in the same manner as in Example 1 except that SEBS-1 was not used and the blending ratio at the time of charging each resin was the blending ratio shown in Table 1. I got each. Table 1 shows the results of evaluating the physical properties of the resin composition using the obtained test pieces for measuring physical properties, together with the blending ratio at the time of charging the resin composition. In addition, morphology observation was carried out using a test piece for measuring physical properties used for measuring the Charpy impact strength. FIG. 4 shows an FE-SEM photograph of the frozen fracture surface of the test piece for measuring physical properties obtained in Comparative Example 1 after oxygen plasma treatment, and FIG. 5 shows a test piece for measuring physical characteristics obtained in Comparative Example 2. The FE-SEM photograph after the freezing fracture surface is subjected to oxygen plasma treatment, and the FE-SEM photograph after the freezing fracture surface of the test piece for measuring physical properties obtained in Comparative Example 3 is subjected to oxygen plasma treatment in FIG. Are shown respectively.

As shown in FIGS. 4 to 5, in the resin composition obtained without using SEBS-1, a dispersed phase composed of PA11 was confirmed in the continuous phase composed of PP, but the maximum diameter was 10 μm or more. No dispersed phase was confirmed (Comparative Examples 1 and 2). Further, as shown in FIG. 6, even if the amount of PA11 charged is increased, in the resin composition obtained without using SEBS-1, a co-continuous phase composed of a continuous phase composed of PP and a continuous phase composed of PA11. Was formed, and a dispersed phase was confirmed in each continuous phase, but a dispersed phase having a maximum diameter of 10 μm or more was not confirmed (Comparative Example 3).

(Example 2)
In the production of the resin composition, the blending ratio at the time of charging each resin is set as the blending ratio shown in Table 2, and in the melt kneading, the carbon fiber (CF, manufactured by Toray Co., Ltd., "TV14-006", average aspect ratio: 100 to 900) was further added so that the mass ratio (mass of PA11: mass of PP: mass of m-EBR: mass of SEBS-1: mass of CF) was 48: 16: 8: 8: 20. Except for the above, a test piece for measuring physical properties was obtained in the same manner as in Example 1. Table 2 shows the results of evaluating the physical properties of the resin composition using the obtained test pieces for measuring physical properties, together with the blending ratio at the time of charging the resin composition. Further, morphology observation was carried out using the test piece for measuring physical properties used for the measurement of the Charpy impact strength, and the obtained coarse dispersion phase ratio is also shown in Table 2.

(Comparative Example 4)
In the production of the resin composition, a test piece for measuring physical characteristics was obtained in the same manner as in Example 2 except that SEBS-1 was not used and the compounding ratio at the time of charging each resin was set to the compounding ratio shown in Table 2. rice field. Table 2 shows the results of evaluating the physical properties of the resin composition using the obtained test pieces for measuring physical properties, together with the blending ratio at the time of charging the resin composition. Table 2 also shows the coarse dispersion phase ratio obtained by morphological observation using the test piece for measuring physical properties used for the measurement of Charpy impact strength.

(Example 3 , Comparative Examples 8 to 10 )
In the production of the resin composition, instead of SEBS-1, SEBS-2 (Example 3): styrene-ethylene / butylene-styrene copolymer (manufactured by Asahi Kasei Chemicals Co., Ltd., "Tough Tech H1062"), EOR ( Comparative Example) 8 ): Ethylene-1-octene copolymer (manufactured by Dow Chemical Japan Co., Ltd., "Engage XLT8677"), EBR ( Comparative Example 9 ): ethylene-1-butene copolymer (manufactured by Mitsui Chemicals Co., Ltd., "Toughmer" DF610 ”), EPR ( Comparative Example 10 ): For measuring each physical property in the same manner as in Example 2 except that an ethylene-propylene copolymer (manufactured by Mitsui Chemicals Co., Ltd.,“ Toughmer P-0680 ”) was used. Each test piece was obtained. Table 3 shows the results of evaluating the physical properties of the resin composition using the obtained test pieces for measuring physical properties, together with the blending ratio of each resin composition at the time of preparation. In addition, Table 3 also shows the results of evaluating the blending ratio and physical properties of the resin composition of Example 2 at the time of preparation.

(Comparative Examples 5 to 6)
In the production of the resin composition, instead of SEBS-1, EMMA (Comparative Example 5): ethylene-methylmethacrylate copolymer (manufactured by Sumitomo Chemical Co., Ltd., "Acrylift WK307"), TPEE (Comparative Example 6): polyester -Test pieces for measuring physical properties were obtained in the same manner as in Example 2 except that a polyether copolymer (manufactured by Mitsubishi Chemical Corporation, "Primaloy A1600N") was used. Table 3 shows the results of evaluating the physical properties of the resin composition using the obtained test pieces for measuring physical properties, together with the blending ratio of each resin composition at the time of preparation.

(Examples 7 and 9 , Comparative Example 11 )
In the production of the resin composition, SEBS-2 or EBR is used instead of SEBS-1, and CF is used instead of GF-1 (Example 7, Comparative Example 11 ): Glass fiber (manufactured by Nippon Electric Glass Co., Ltd., " T-120H ”, average aspect ratio: 200 to 400) or GF-2 (Example 9): Other than using glass fiber (Nippon Electric Glass,“ T-262H ”, average aspect ratio: 200 to 400) Obtained each test piece for measuring physical properties in the same manner as in Example 2. Table 4 shows the results of evaluating the physical properties of the resin composition using the obtained test pieces for measuring physical properties, together with the blending ratio of each resin composition at the time of preparation.

(Comparative Example 7)
In the production of the resin composition, SEBS-1 was not used, GF-1 was used instead of CF, and the blending ratios of each resin at the time of charging were set to the blending ratios shown in Table 4, except that the blending ratios were the same as those of Example 2. Similarly, a test piece for measuring physical properties was obtained. Table 4 shows the results of evaluating the physical properties of the resin composition using the obtained test pieces for measuring physical properties, together with the blending ratio at the time of charging the resin composition.

As is clear from the results shown in FIGS. 2 to 3, the resin composition of the present invention comprises a continuous phase A (10) composed of a polyamide resin (PA11) and a polyolefin resin (PP) dispersed in the continuous phase A. _{), The finely dispersed phase a 1} '(31) composed of the polyamide resin (PA11) dispersed in the dispersed phase a, and the unmodified elastomer (SEBS) dispersed in the dispersed phase a. A microdisperse phase a ₂ '(32) composed of -1) is provided, and at least a part of the modified elastomer (m-EBR) is in the continuous phase A, in the microdisperse phase a ₁ '(42), and in the continuous phase A. It was confirmed that the structure exists at the interface between the dispersed phase a and the dispersed phase a and the interface between the dispersed phase a and the finely dispersed phase a _1'. It was also confirmed that the dispersed phase b (21) composed of the unmodified elastomer dispersed in the continuous phase A exists. Further, in the resin composition of the present invention, it was confirmed that the total cross-sectional area of the dispersed phase a having a maximum diameter of 10 μm or more is 25% or more of the total cross-sectional area of all the dispersed phases a. ..

Further, as is clear from the results shown in Tables 1 to 4, the resin composition of the present invention having the above structure exhibits excellent rigidity and also exhibits remarkably excellent impact resistance. confirmed. Furthermore, it was confirmed that the resin composition of the present invention can maintain excellent impact resistance even when a filler is added.

As described above, according to the present invention, there is provided a resin composition capable of exhibiting excellent impact resistance and rigidity and maintaining excellent impact resistance even when a filler is added. It becomes possible to do.

10 ... Continuous phase A (polyamide resin (PA)), 20 ... Dispersion phase a (polyform resin (PO)), 21 ... Dispersion phase c (unmodified elastomer), 31 ... Finely dispersed phase a ₁ '(polyamide resin (PA)) )), 32 ... finely dispersed phase a ₂ '(unmodified elastomer), 41 ... modified elastomer (dispersed phase b, in continuous phase (PA)), 42 ... modified elastomer (ultrafine dispersed phase a'', finely dispersed phase (In (PA)), 43 ... Modified elastomer (continuous phase (PA) -dispersed phase (PO) interface), 44 ... modified elastomer (dispersed phase (PO) -finely dispersed phase (PA) interface), 45 ... modified elastomer ( Continuous phase (PA) -dispersed phase c (unmodified elastomer) interface).

Claims (7)

A resin composition containing a polyamide resin, a polyolefin resin, a modified elastomer having a functional group capable of binding to the polyamide resin, and an unmodified elastomer having substantially no functional group.
The polyolefin resin is at least one selected from the group consisting of polypropylene resin and polyethylene resin.
The modified elastomer is a modified olefin-based thermoplastic elastomer.
The unmodified elastomer is a styrene-based thermoplastic elastomer.
The content of the polyamide resin is 50 to 70% by mass with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer.
The content of the polyolefin resin is 10 to 35% by mass with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer.
The content of the modified elastomer is 5 to 25% by mass with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer.
The content of the unmodified elastomer is 5 to 25% by mass with respect to the total mass of the polyamide resin, the polyolefin resin, the modified elastomer and the unmodified elastomer.
The continuous phase A made of the polyamide resin, the dispersed phase a made of the polyolefin resin dispersed in the continuous phase A, the finely dispersed phase a ₁ ′ made of the polyamide resin dispersed in the dispersed phase a, and the undeveloped phase a1'. consists modified elastomer and a finely dispersed phase a _{2 ',}
At least a portion of the modified elastomer is present in the interface of the continuous phase A, finely dispersed phase a _{1 'in} the interface between the continuous phase A and the dispersed phase a, and a dispersed phase a finely dispersed phase a _1' and ,
In the resin phase-separated cross-sectional structure observed with an electron microscope, the total cross-sectional area of the dispersed phase a having a maximum diameter of 10 μm or more (including the cross-sectional area of other phases in the dispersed phase a) is the total of all the dispersed phases a. 25% or more of the total cross-sectional area of
A resin composition characterized by this. The resin composition according to claim 1, further comprising a filler. The resin composition according to claim 2, wherein the filler has an average aspect ratio of 10 or more. The resin composition according to claim 2 or 3, wherein the filler is at least one selected from the group consisting of carbon fibers and glass fibers. In the resin phase-separated cross-sectional structure observed with an electron microscope, the total cross-sectional area of all the dispersed phases a (including the cross-sectional areas of other phases in the dispersed phase a) is the total cross-sectional area of the resin composition. The resin composition according to any one of claims 1 to 4, wherein the resin composition is 20 to 80%. In the resin phase separation sectional structures observed by an electron microscope, total, the resin composition of any of _'the cross-sectional area of the (fine dispersed phase a _1' finely dispersed phase a ₁ including the cross-sectional area of the other phases in) The resin composition according to any one of claims 1 to 5, which is 1 to 30% with respect to the total cross-sectional area of the above. In the resin phase separation sectional structures observed by an electron microscope, total, the resin composition of any of _'the cross-sectional area of the (fine dispersed phase a _2' finely dispersed phase a ₂ includes the cross-sectional area of the other phases in) The resin composition according to any one of claims 1 to 6, wherein the resin composition is 1 to 30% with respect to the total cross-sectional area of the above.

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