JP6838392B2 - Resin composition and resin molded product - Google Patents

Description

The present invention relates to a resin composition and a resin molded product.

Conventionally, various resin compositions have been provided and used for various purposes.
In particular, the resin composition containing a thermoplastic resin is used for various parts of home appliances and automobiles, housings, and parts such as office equipment and housings of electronic and electrical equipment.

For example, Patent Document 1 states that "(a) 0.1 to 90% by weight of at least one type of polyolefin, (b) 0.1 to 50% by weight of at least one type of polyamide, and (c) 0.1 to 0% by weight. 15% by weight of at least one modified polyolefin, (d) 5.0 to 75% by weight of at least one reinforcing fiber, (e) 0.1 to 10% by weight of at least one sulfur-containing additive. A long fiber reinforced polyolefin structure having a length of 3 mm or more including the above is disclosed.

Further, Patent Document 2 states that "an acid-modified polyolefin (A) block and a polyamide (B) block are provided, ^{and carbon derived from an amide group by 13} C-NMR and carbon derived from a methyl group, a methylene group and a methine group are used. A modifier for a polyolefin resin containing a polymer (X) having a ratio (α) of 0.5 / 99.5 to 12/88 ”is disclosed. Further, Patent Document 2 discloses "an inorganic fiber-containing polyolefin resin composition containing the modifier (K) for a polyolefin resin, a polyolefin resin (D) and an inorganic fiber (E)." ..
Patent Document 3 states, "In a thermoplastic resin molded product containing carbon fibers, the total content of the carbon fibers contained in the molded product is 0.5 to 30 wt%, and the length further exceeds 1.5 mm. Is disclosed as a carbon fiber-containing thermoplastic resin molded product, which comprises 0.1 to 4.7 wt% of carbon fibers.

Special Table 2003-528965 Japanese Unexamined Patent Publication No. 2014-181307 Japanese Unexamined Patent Publication No. 2000-071245

An object of the present invention is that in a resin composition composed of a thermoplastic resin, a reinforcing fiber, a resin containing at least one of an amide bond and an imide bond, and a compatibilizer, the resin containing at least one of the amide bond and the imide bond is crystallized. It is an object of the present invention to provide a resin composition capable of obtaining a resin molded body having excellent stability against temperature changes (temperature cycle stability) as compared with the case where it is composed of only a sex resin.

The above object is achieved by the following invention.

The invention according to <1 > is
With thermoplastic resin
With carbon fiber
Amorphous resins containing at least one of an amide bond and an imide bond,
With a compatibilizer,
It is a resin composition containing.

The invention according to <2 > is
The resin composition according to < 1 > , which further comprises a crystalline resin containing at least one of an amide bond and an imide bond.

The invention according to <3 > is
The resin composition according to < 1 > or < 2 > , wherein the content of the carbon fibers is 0.1 part by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin.

The invention according to <4 > is
The resin composition according to any one of < 1 > to < 3 > , wherein the average fiber length of the carbon fibers is 0.1 mm or more and 5.0 mm or less.

The invention according to <5 > is
The resin composition according to any one of < 1 > to < 4 > , wherein the thermoplastic resin is a polyolefin.

The invention according to <6 > is
The resin composition according to any one of < 1 > to < 5 > , wherein the amorphous resin containing at least one of the amide bond and the imide bond is a polyamide.

The invention according to <7 > is
The resin composition according to any one of < 1 > to < 6 > , wherein the compatibilizer is a modified polyolefin.

The invention according to <8 > is
The total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond is 0.1 with respect to 100 parts by mass of the thermoplastic resin. The resin composition according to < 2 > , which is equal to or more than 100 parts by mass and not more than 100 parts by mass.

The invention according to <9 > is
The resin composition according to any one of < 1 > to < 8 > , wherein the content of the compatibilizer is 0.1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. ..

The invention according to <10 > is
The total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond with respect to the total mass of the carbon fibers is 0.1 mass by mass. The resin composition according to < 2 > , which is% or more and 1,000% by mass or less.

The invention according to <11 > is
The resin composition according to any one of < 1 > to < 10 > , wherein the content of the compatibilizer with respect to the total mass of the carbon fibers is 1% by mass or more and 50% by mass or less.

The invention according to <12 > is
With thermoplastic resin
With carbon fiber
Amorphous resins containing at least one of an amide bond and an imide bond,
With a compatibilizer,
It is a resin molded product containing.

The invention according to <13 > is
The resin molded product according to < 12 > , which further contains a crystalline resin containing at least one of an amide bond and an imide bond.

The invention according to <14 > is
The resin molded product according to < 12 > or < 13 > , wherein the content of the carbon fibers is 0.1 part by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin.

The invention according to <15 > is
The resin molded product according to any one of < 12 > to < 14 > , wherein the average fiber length of the carbon fibers is 0.1 mm or more and 5.0 mm or less.

The invention according to <16 > is
The resin molded product according to any one of < 12 > to < 15 > , wherein the thermoplastic resin is a polyolefin.

The invention according to <17 > is
The resin molded product according to any one of < 12 > to < 16 > , wherein the amorphous resin containing at least one of the amide bond and the imide bond is a polyamide.

The invention according to <18 > is
The resin molded product according to any one of < 12 > to < 17 > , wherein the compatibilizer is a modified polyolefin.

The invention according to <19 > is
The total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond is 0.1 with respect to 100 parts by mass of the thermoplastic resin. The resin molded body according to < 13 > , which is equal to or more than 100 parts by mass and less than 100 parts by mass.

The invention according to <20 > is
The resin molded product according to any one of < 12 > to < 19 > , wherein the content of the compatibilizer is 0.1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. ..

The invention according to <21 > is
The total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond with respect to the total mass of the carbon fibers is 0.1 mass by mass. The resin molded product according to < 13 > , which is% or more and 1,000% by mass or less.

The invention according to <22 > is
The resin molded product according to any one of < 12 > to < 21 > , wherein the content of the compatibilizer with respect to the total mass of the carbon fibers is 1% by mass or more and 50% by mass or less.

According to the invention according to < 1 > , in a resin composition comprising a thermoplastic resin, a reinforcing fiber, a resin containing at least one of an amide bond and an imide bond, and a compatibilizer, at least one of the amide bond and the imide bond is formed. Provided is a resin composition capable of obtaining a resin molded body having excellent stability against temperature changes (temperature cycle stability) as compared with the case where the contained resin is composed of only a crystalline resin.
According to the invention according to < 2 > , a resin composition capable of obtaining a resin molded product having excellent impact resistance as compared with the case where the resin containing at least one of the amide bond and the imide bond is composed of only an amorphous resin. Is provided.
According to the invention according to < 3 > , a resin molded product having excellent impact resistance as compared with the case where the carbon fiber content is less than 0.1 part by mass or more than 200 parts by mass with respect to 100 parts by mass of the thermoplastic resin. Is provided.
According to the invention according to < 4 >, there is provided a resin composition capable of obtaining a resin molded product having excellent impact resistance as compared with the case where the average fiber length of carbon fibers is less than 0.1 mm or more than 5.0 mm. To.
According to the invention according to < 5 >, there is provided a resin composition capable of obtaining an inexpensive resin molded product as compared with the case where an achlorinitrile butadiene styrene copolymer or a general-purpose resin of a styrene polymer is used as the thermoplastic resin.
According to the invention according to < 6 >, there is provided a resin composition capable of obtaining a resin molded product having excellent impact resistance as compared with the case where polyimide is used as a resin containing at least one of an amide bond and an imide bond.
According to the invention according to < 7 >, there is provided a resin composition capable of obtaining a resin molded product having excellent impact resistance as compared with the case where an epoxy copolymer is used as a compatibilizer.
According to the invention according to < 8 > , the total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond is the thermoplastic resin. Provided is a resin composition capable of obtaining a resin molded body having excellent impact resistance as compared with the case where the amount is less than 0.1 part by mass or more than 100 parts by mass with respect to 100 parts by mass.
According to the invention according to < 9 > , resin molding having excellent impact resistance as compared with the case where the content of the compatibilizer is less than 0.1 part by mass or more than 50 parts by mass with respect to 100 parts by mass of the thermoplastic resin. A resin composition from which the body is obtained is provided.
According to the invention according to < 10 > , the total amount of the amorphous resin containing at least one of the amide bond and the imide bond with respect to the total mass of the carbon fibers, and the total of the crystalline resin containing at least one of the amide bond and the imide bond. Provided is a resin composition capable of obtaining a resin molded body having excellent impact resistance as compared with the case where the content is less than 1% by mass or more than 1,000% by mass.
According to the invention according to < 11 > , a resin molded product having excellent impact resistance can be obtained as compared with the case where the content of the compatibilizer with respect to the total mass of the carbon fibers is less than 1% by mass or more than 50% by mass. A resin composition is provided.

According to the invention according to < 12 > , a resin composition comprising a thermoplastic resin, a reinforcing fiber, a resin containing at least one of an amide bond and an imide bond, and a compatibilizer is used, and at least one of the amide bond and the imide bond is used. Provided is a resin molded body having excellent stability against temperature changes (temperature cycle stability) as compared with the case where the resin containing the above is composed of only a crystalline resin.
According to the invention according to < 13 > , a resin molded product having excellent impact resistance is provided as compared with the case where the resin containing at least one of the amide bond and the imide bond is composed of only an amorphous resin.
According to the invention according to < 14 > , a resin molded product having excellent impact resistance as compared with the case where the carbon fiber content is less than 0.1 part by mass or more than 200 parts by mass with respect to 100 parts by mass of the thermoplastic resin. Is provided.
According to the invention of < 15 > , a resin molded product having excellent impact resistance is provided as compared with the case where the average fiber length of carbon fibers is less than 0.1 mm or more than 5.0 mm.
According to the invention according to < 16 > , an inexpensive resin molded product is provided as compared with the case where an achlorinitrile butadiene styrene copolymer or a general-purpose resin of a styrene polymer is used as the thermoplastic resin.
According to the invention according to < 17 > , a resin molded product having excellent impact resistance is provided as compared with the case where polyimide is used as a resin containing at least one of an amide bond and an imide bond.
According to the invention according to < 18 > , a resin molded product having excellent impact resistance as compared with the case where an epoxy copolymer is used as a compatibilizer is provided.
According to the invention according to < 19 > , the total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond is a thermoplastic resin. A resin molded body having excellent impact resistance is provided as compared with the case where the amount is less than 0.1 part by mass or more than 100 parts by mass with respect to 100 parts by mass.
According to the invention according to < 20 > , resin molding having excellent impact resistance as compared with the case where the content of the compatibilizer is less than 0.1 part by mass or more than 50 parts by mass with respect to 100 parts by mass of the thermoplastic resin. The body is provided.
According to the invention according to < 21 > , the total amount of the amorphous resin containing at least one of the amide bond and the imide bond with respect to the total mass of the carbon fibers, and the total of the crystalline resin containing at least one of the amide bond and the imide bond. A resin molded body having excellent impact resistance is provided as compared with the case where the content is less than 1% by mass or more than 1,000% by mass.
According to the invention of < 22 > , a resin molded product having excellent impact resistance is provided as compared with the case where the content of the compatibilizer with respect to the total mass of the carbon fibers is less than 1% by mass or more than 50% by mass. To.

It is a model figure which shows the main part of the resin molded body which concerns on this embodiment. It is a schematic diagram for demonstrating an example of the main part of the resin molded article which concerns on this embodiment.

Hereinafter, embodiments that are examples of the resin composition and the resin molded product of the present invention will be described.

[Resin composition]
The resin composition according to the present embodiment contains a thermoplastic resin, carbon fibers, an amorphous resin containing at least one of an amide bond and an imide bond, and a compatibilizer.
Hereinafter, an amorphous resin containing at least one of an amide bond and an imide bond may be referred to as a "specific amorphous resin".

In recent years, in order to obtain a resin molded product having excellent mechanical strength, a resin composition containing a thermoplastic resin as a base material (matrix) and reinforcing fibers has been used.
When such a resin composition is molded, the volume of the resin molded product generally shrinks from a high temperature immediately after molding to cooling, that is, shrinkage occurs.
Internal stress (also referred to as residual stress) is generated inside the resin molded product due to the heat and external force during molding and the shrinkage. Shrinkage Internal stress is likely to occur between the reinforcing fiber and the thermoplastic resin used as the matrix because there is a difference in the shrinkage ratio and the shrinkage behavior with respect to temperature. When the internal stress is gradually released due to the passage of time, a temperature change, or the like, strain may occur inside the resin molded product, and the resin molded product may be deformed or damaged. In addition, the strain accumulated inside the molded body even if it does not actually deform or break may gradually cause the molded body to be deformed or broken due to the external stress repeatedly applied to the molded body or the stress caused by the temperature change. is there.
In particular, when the temperature changes, the thermal conductivity of the resin is generally low, so that the inside of the resin molded body is liable to be distorted, and the resin is liable to be deformed or damaged. That is, the temperature cycle stability may not be sufficient.

Therefore, the resin composition according to the present embodiment contains four components: a thermoplastic resin, carbon fibers, an amorphous resin containing at least one of an amide bond and an imide bond, and a compatibilizer.
With this configuration, a resin molded product having excellent temperature cycle stability can be obtained. The action to obtain such an effect is not clear, but it is presumed as follows.

Resins containing at least one of amide bond and imide bond, for example, polyamide resin, polyimide resin, polyamideimide resin and the like are often crystalline, and the resin containing at least one of amide bond and imide bond is crystalline. By containing an amorphous resin containing at least one of an amide bond and an imide bond, the amorphous portion made of the amorphous resin has an internal stress of the resin molded body due to molding, as compared with the case of using the above alone. And it is considered that the strain is relaxed and the shrinkage during molding is reduced.
By reducing the strain of the resin molded product and reducing the shrinkage during molding, deformation and breakage of the resin molded product due to the passage of time and temperature changes are suppressed, and the stability of the obtained resin molded product against temperature changes is suppressed. It is considered to be excellent in (temperature cycle stability).
When a polyamide resin or the like is formed as a coating layer on the surface of the carbon fiber, which is an example of the present embodiment, distortion is likely to occur between the carbon fiber and the coating layer, and a highly crystalline material is used for the polyamide resin or the like. If it is used, it is considered that distortion is likely to occur during crystallinity of the polyamide resin or the like in the cooling step during molding. On the other hand, it is considered that by applying a non-crystalline material to the polyamide resin or the like of the coating layer, distortion due to crystallization is less likely to occur, and fracture deformation due to temperature change is less likely to occur.

From the above, it is presumed that the resin composition according to the present embodiment can obtain a resin molded product having excellent temperature cycle stability.

Further, when a resin molded body is obtained from the resin composition according to the present embodiment, when the resin composition is thermally melted, the thermoplastic resin as the base material and the compatibilizer are melted, and the molecules of the compatibilizer are also melted. A part of the resin and the amide bond or the imide bond contained in the molecule of the specific amorphous resin are compatible with each other, and the specific amorphous resin is dispersed in the resin composition.
In this state, when the specific amorphous resin comes into contact with the carbon fiber, a large number of amide bonds or imide bonds contained along the molecular chain of the specific amorphous resin and polar groups slightly present on the surface of the carbon fiber are present. And are physically bonded at multiple points due to their affinity (attractive force and hydrogen bond).
In addition, since the thermoplastic resin and the specific amorphous resin generally have low compatibility, the contact frequency between the specific amorphous resin and the carbon fiber due to the repulsive force between the thermoplastic resin and the specific amorphous resin. As a result, the amount of adhesion of the specific amorphous resin to the carbon fiber and the adhesion area increase. In this way, a coating layer made of the specific amorphous resin is formed around the carbon fibers (see FIG. 1). In FIG. 1, PP indicates a thermoplastic resin, CF indicates a carbon fiber, and CL indicates a coating layer.
Then, the specific amorphous resin forming the coating layer is also compatible with some of the reactive groups in the molecule of the compatibilizer by performing a chemical reaction and electrostatic interaction between the polar groups. When the solubilizer is also compatible with the thermoplastic resin, an attractive force and a repulsive force are formed in an equilibrium state, and the coating layer made of the specific amorphous resin is formed in a thin and nearly uniform state. In particular, since the carboxy group existing on the surface of the carbon fiber has a high affinity for the amide bond or the imide bond contained in the molecule of the specific amorphous resin, a coating layer made of the specific amorphous resin is used around the carbon fiber. Is easily formed, and it is considered that the coating layer is a thin film and has excellent uniformity.
Therefore, it is presumed that the obtained resin molded product is also excellent in impact resistance.

The coating layer preferably covers the entire periphery of the carbon fiber, but there may be a partially uncoated portion.
When a crystalline resin (specific crystalline resin) containing at least one of an amide bond and an imide bond, which will be described later, is used in combination, the coating layer is formed in a state of being mixed with the specific amorphous resin. Is presumed to form.

In the resin composition according to the present embodiment, the thickness of the coating layer made of the specific amorphous resin (and the specific crystalline resin) is 5 nm or more and 700 nm or less, and 10 nm or more and 650 nm or less from the viewpoint of improving impact resistance. Is preferable. When the thickness of the coating layer is 5 nm or more (particularly 10 nm or more), the impact resistance is improved, and when the thickness of the coating layer is 700 nm or less, the interface between the carbon fiber and the thermoplastic resin via the coating layer becomes fragile. This is suppressed, and the decrease in impact resistance is suppressed.

The thickness of the coating layer is a value measured by the following method. The object to be measured is broken in liquid nitrogen, and its cross section is observed using an electron microscope (VE-9800 manufactured by Keyence Corporation). In the cross section, the thickness of the coating layer covering around the carbon fiber is measured at 100 points and calculated as the average value.
The coating layer is confirmed by observing the cross section.

The resin composition (and its resin molded product) according to the present embodiment has, for example, a configuration in which a compatibilizer is partially compatible between the coating layer and the thermoplastic resin.
Specifically, for example, a layer of a compatibilizer may be interposed between the coating layer made of the specific amorphous resin and the thermoplastic resin which is the base material (see FIG. 2). That is, it is preferable that a layer of the compatibilizer is formed on the surface of the coating layer, and the coating layer and the thermoplastic resin are adjacent to each other via the layer of the compatibilizer. The layer of the compatibilizer is formed thinner than the coating layer, but the presence of the compatibilizer layer enhances the adhesion (adhesiveness) between the coating layer and the thermoplastic resin, and mechanical strength, especially impact resistance. It becomes easy to obtain an excellent resin molded product. In FIG. 2, PP indicates a thermoplastic resin, CF indicates a carbon fiber, CL indicates a coating layer, and CA indicates a layer of a compatibilizer.

In particular, the layer of the compatibilizer is bonded to the coating layer (hydrogen bond, covalent bond by the reaction of the functional group of the compatibilizer and the specific amorphous resin, etc.) and is compatible with the thermoplastic resin. , It is preferable that it is interposed between the coating layer and the thermoplastic resin. In this configuration, for example, as a compatibilizer, it has the same structure or a structure that is compatible with the thermoplastic resin that is the base material, and partially reacts with the functional group of the above-mentioned specific amorphous resin in the molecule. It is easy to realize by applying a compatibilizer containing the site to be treated.
Specifically, for example, when a polyolefin is applied as the thermoplastic resin, a polyamide is applied as the specific amorphous resin, and a maleic anhydride-modified polyolefin is applied as the compatibilizer, a layer of the maleic anhydride-modified polyolefin (layer of the compatibilizer). The carboxy group generated by opening the ring of the maleic anhydride moiety reacts with the amine residue of the polyamide layer (coating layer) and binds to the maleic anhydride moiety, and the polyolefin moiety is intervened in a state of being compatible with the polyolefin. That is good.

The method is as follows.
A micro-infrared spectroscopic analyzer (IRT-5200 manufactured by JASCO Corporation) is used as the analyzer. For example, a slice piece is cut out from a resin molded body composed of polypropylene (hereinafter PP) as a thermoplastic resin, PA6I6T as a specific amorphous resin, and maleic acid-modified polypropylene (hereinafter MA-PP) as a compatibilizer, and its cross section is cut out. Observed. The covering layer section surrounding the carbon fiber cross section subjected to IR mapping, the coating layer - was confirmed compatibilizer layer from maleic anhydride (1820 cm ^-1 or less 1750 cm ^-1 or higher). It was also confirmed with terminal steroid-modified PA-derived amide group garment portion (1680 cm ^-1 to 1630 cm ^-1) and secondary amino group (3320 cm ^-1 to 3140cm ^-1). As a result, it can be confirmed that the clothing layer is formed on the surface of the carbon fiber, and that a layer (bonding layer) of the compatibilizer is interposed between the coating layer and the thermoplastic resin. Specifically, when MA-PP and PA6I6T are reacting, the cyclic maleinated portion of MA-PP is ring-opened and the amine residue of PA6I6T is chemically bonded to reduce the cyclic maleated portion. It can be confirmed that a layer of the compatibilizer (bonding layer) is interposed between the and the thermoplastic resin.

Hereinafter, details of each component of the resin composition according to the present embodiment will be described.

-Thermoplastic resin-
The thermoplastic resin is a base material of a resin composition and refers to a resin component reinforced by carbon fibers (also called a matrix resin).
The thermoplastic resin is not particularly limited, and for example, polyolefin (PO), polyphenylene terephthalide (PPS), polyamide (PA), polyimide (PI), polyamideimide (PAI), polyetherimide (PEI), and the like. Polyetheretherketone (PEEK), polyethersulfone (PES), polyphenylsulfone (PPSU), polysulfone (PSF), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyacetal (POM), polycarbonate (PC) ), Polybutylene terephthalide (PVDF), acrylonitrile butadiene styrene copolymer (ABS), acrylonitrile styrene (AS) and the like.
One type of thermoplastic resin may be used alone, or two or more types may be used in combination.

Among these, polyolefin (PO) is preferable from the viewpoint of further improvement of impact resistance and cost.
The polyolefin is a resin containing a repeating unit derived from an olefin, and may contain a repeating unit derived from a monomer other than the olefin as long as it is 30% by mass or less with respect to the entire resin.
Polyolefins are obtained by addition polymerization of olefins (optionally non-olefin monomers).
Further, the olefin and the monomers other than the olefin for obtaining the polyolefin may be one kind or two or more kinds, respectively.
The polyolefin may be a copolymer or a homopolymer. Further, the polyolefin may be linear or branched.

Here, examples of the olefin include a linear or branched aliphatic olefin and an alicyclic olefin.
Examples of the aliphatic olefin include α-olefins such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-hexadecene and 1-octadecene.
Examples of the alicyclic olefin include cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, vinylcyclohexane and the like.
Among them, from the viewpoint of cost, α-olefin is preferable, ethylene and propylene are more preferable, and propylene is particularly preferable.

The monomer other than the olefin is selected from known addition-polymerizable compounds.
Examples of the addition polymerizable compound include styrenes such as styrene, methylstyrene, α-methylstyrene, β-methylstyrene, t-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid or a salt thereof; (Meta) acrylic acid esters such as alkyl (meth) acrylate, benzyl (meth) acrylate, dimethylaminoethyl (meth) acrylate; halovinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; Vinyl ethers such as vinyl methyl ether; halogenated vinylidene such as vinylidene chloride; N-vinyl compounds such as N-vinylpyrrolidone; and the like can be mentioned.

Suitable polyolefins include polypropylene (PP), polyethylene (PE), polybutene, polyisobutylene, kumaron-inden resin, terpene resin, ethylene-vinyl acetate copolymer resin (EVA) and the like.
Of these, a resin containing only repeating units derived from olefins is preferable, and polypropylene is particularly preferable from the viewpoint of cost.

The molecular weight of the thermoplastic resin is not particularly limited, and may be determined according to the type of resin, molding conditions, application to the resin molded product, and the like. For example, when the thermoplastic resin is a polyolefin, its weight average molecular weight (Mw) is preferably in the range of 10,000 or more and 300,000 or less, and more preferably in the range of 10,000 or more and 200,000 or less.
Further, the glass transition temperature (Tg) or melting point (Tm) of the thermoplastic resin is not particularly limited as in the above molecular weight, and may be determined according to the type of resin, molding conditions, application to the resin molded product, and the like. For example, when the thermoplastic resin is polyolefin, its melting point (Tm) is preferably in the range of 100 ° C. or higher and 300 ° C. or lower, and more preferably in the range of 150 ° C. or higher and 250 ° C. or lower.

The weight average molecular weight (Mw) and melting point (Tm) of the polyolefin show the values measured as follows.
That is, the weight average molecular weight (Mw) of the polyolefin is determined by gel permeation chromatography (GPC) under the following conditions. A high-temperature GPC system "HLC-8321GPC / HT" is used as the GPC apparatus, and o-dichlorobenzene is used as the eluent. The polyolefin is once melted and filtered into o-dichlorobenzene at a high temperature (temperature of 140 ° C. or higher and 150 ° C. or lower), and the filtrate is used as a measurement sample. The measurement conditions were a sample concentration of 0.5% and a flow velocity of 0.6 ml / min. , Sample injection volume 10 μl, using an RI detector. The calibration curve is "polystylene standard sample TSK standard" manufactured by Tosoh Corporation: "A-500", "F-1", "F-10", "F-80", "F-380", "A-". It is prepared from 10 samples of "2500", "F-4", "F-40", "F-128", and "F-700".
Further, the melting point (Tm) of the polyolefin is determined from the DSC curve obtained by differential scanning calorimetry (DSC), as described in "Melting peak" described in JIS K 7121-1987 "Method for measuring transition temperature of plastics". Obtained by "temperature".

The content of the thermoplastic resin may be determined according to the intended use of the resin molded product, and is preferably 5% by mass or more and 95% by mass or less, preferably 10% by mass, based on the total mass of the resin composition. More than 95% by mass or less is more preferable, and 20% by mass or more and 95% by mass or less is further preferable.
When polyolefin is used as the thermoplastic resin, it is preferable that 20% by mass or more of the polyolefin is used with respect to the total mass of the thermoplastic resin.

-Carbon fiber-
As the carbon fiber, a known carbon fiber is used, and both a PAN-based carbon fiber and a pitch-based carbon fiber are used.

The carbon fiber may be one that has been subjected to a known surface treatment.
Examples of the surface treatment of the carbon fiber include an oxidation treatment and a sizing treatment.
The form of the carbon fiber is not particularly limited, and may be selected depending on the intended use of the resin molded product and the like. Examples of the form of carbon fibers include fiber bundles composed of a large number of single fibers, bundles of fiber bundles, and woven fabrics in which fibers are woven two-dimensionally or three-dimensionally.

The fiber diameter, fiber length, etc. of the carbon fiber are not particularly limited, and may be selected according to the application of the resin molded product and the like.
However, even if the fiber length of the carbon fiber is short, a resin molded product having excellent impact resistance can be obtained. Therefore, the average fiber length of the carbon fiber is 0.1 mm or more and 5.0 mm or less (preferably 0.2 mm or more 2). It may be 0.0 mm or less).
The average diameter of the carbon fibers may be, for example, 5.0 μm or more and 10.0 μm or less (preferably 6.0 μm or more and 8.0 μm or less).

Here, the method for measuring the average fiber length of carbon fibers is as follows. The carbon fibers are observed with an optical microscope at a magnification of 100, and the length of the carbon fibers is measured. Then, this measurement is performed on 200 carbon fibers, and the average value thereof is taken as the average fiber length of the carbon fibers.
On the other hand, the method for measuring the average diameter of carbon fibers is as follows. A cross section orthogonal to the length direction of the carbon fiber is observed by an SEM (scanning electron microscope) at a magnification of 1000 times, and the diameter of the carbon fiber is measured. Then, this measurement is performed on 100 carbon fibers, and the average value thereof is taken as the average diameter of the carbon fibers.

When the fiber length of the carbon fiber is shortened, the resin reinforcing ability of the carbon fiber tends to decrease. In particular, in recent years, due to the demand for recycling, the resin molded product reinforced with carbon fibers has been crushed and reused, and the fiber length of the carbon fiber is often shortened when the resin molded product is crushed. .. In addition, the fiber length of the carbon fibers may be shortened during hot melt kneading during the production of the resin composition. Therefore, when a resin molded product is molded from a resin composition containing carbon fibers having a shortened fiber length, the mechanical strength, particularly the impact resistance, tends to decrease.
However, even if the resin molded body containing the carbon fibers is crushed and a recycled product in which the carbon fibers are shortened is used as a raw material, or the carbon fibers are shortened during hot melt kneading, the resin composition according to the present embodiment. The material is useful because a resin molded body having excellent impact resistance can be obtained.

As the carbon fiber, a commercially available product may be used.
Commercially available PAN-based carbon fibers include "Treca (registered trademark)" manufactured by Toray Industries, Inc., "Tenax" manufactured by Toho Tenax Co., Ltd., and "Pyrofil (registered trademark)" manufactured by Mitsubishi Rayon Co., Ltd. Can be mentioned. In addition, examples of commercially available PAN-based carbon fibers include commercially available products manufactured by Hexcel, Cytec, Dow-Axa, Formosa Plastics, and SGL.
Examples of commercially available pitch-based carbon fibers include "Dyriad (registered trademark)" manufactured by Mitsubishi Rayon Co., Ltd., "GRANOC" manufactured by Nippon Graphite Fiber Co., Ltd., and "Kureka" manufactured by Kureha Corporation. .. In addition, examples of commercially available pitch-based carbon fibers include commercially available products manufactured by Osaka Gas Chemical Co., Ltd. and Cytec.

As the carbon fiber, one type may be used alone, or two or more types may be used in combination.

The content of the carbon fiber is preferably 0.1 part by mass or more and 200 parts by mass or less, more preferably 1 part by mass or more and 180 parts by mass or less, and 5 parts by mass or more with respect to 100 parts by mass of the thermoplastic resin. It is more preferably 150 parts by mass or less.
By containing 0.1 part by mass or more of carbon fiber with respect to 100 parts by mass of the thermoplastic resin, the resin composition is strengthened, and the content of carbon fiber is 200 parts by mass with respect to 100 parts by mass of the thermoplastic resin. By setting the number of parts or less, the moldability when obtaining a resin molded body is improved.
When reinforcing fibers other than carbon fibers are used, it is preferable that 80% by mass or more of the reinforcing fibers is carbon fibers with respect to the total mass of the reinforcing fibers.

Here, hereinafter, the content (parts by mass) with respect to 100 parts by mass of the thermoplastic resin may be abbreviated as "phr (per hundred parts)".
When this abbreviation is used, the content of the carbon fiber is 0.1 phr or more and 200 phr or less.

-Amorphous resin containing at least one of amide bond and imide bond (specific amorphous resin)-
The resin composition according to the present embodiment contains an amorphous resin containing at least one of an amide bond and an imide bond.
The specific amorphous resin is a resin that contains a specific partial structure and can cover the periphery of carbon fibers as described above.
This specific amorphous resin will be described in detail.

The specific amorphous resin is preferably a resin having low compatibility with the thermoplastic resin, specifically, a resin having a solubility parameter (SP value) different from that of the thermoplastic resin.
Here, the difference in SP value between the thermoplastic resin and the specific amorphous resin is preferably 3 or more, and more preferably 3 or more and 6 or less, from the viewpoint of compatibility between the two and repulsive force between the two.
The SP value referred to here is a value calculated by Fedor's method. Specifically, the solubility parameter (SP value) is, for example, Polym. Eng. Sci. , Vol. 14, p. Based on the description of 147 (1974), the SP value is calculated by the following formula.
Formula: SP value = √ (Ev / v) = √ (ΣΔei / ΣΔvi)
(In the formula, Ev: evaporation energy (cal / mol), v: molar volume (cm ³ / mol), Δei: evaporation energy of each atom or atomic group, Δvi: molar volume of each atom or atomic group)
As the solubility parameter (SP value), (cal / cm ³ ) ^1/2 is adopted as the unit, but the unit is omitted according to the practice and is expressed dimensionlessly.

In addition, the specific amorphous resin contains at least one of an amide bond and an imide bond in the molecule.
By including an imide bond or an amide bond, an affinity is developed with the polar group present on the surface of the carbon fiber.
Specific types of the specific amorphous resin include thermoplastic resins containing at least one of an amide bond and an imide bond in the main chain, and specifically, polyamide (PA), polyimide (PI), and polyamideimide. (PAI), polyetherimide (PEI), polyamino acid and the like can be mentioned.

As the specific amorphous resin, it is preferable that the compatibility with the thermoplastic resin is low and the SP value is different. Therefore, it is preferable to use a thermoplastic resin of a different type from the thermoplastic resin which is the base material.
Of these, polyamide (PA) is preferable from the viewpoint of further improving impact resistance and excellent adhesion to carbon fibers.

Examples of the polyamide include a polyamide obtained by polycondensation of a dicarboxylic acid and a diamine, a polyamide obtained by ring-opening polycondensation of lactam, and a polyamide obtained by condensing a dicarboxylic acid, a diamine and a lactam. That is, as the polyamide, examples of the polyamide include a polyamide having at least one of a structural unit obtained by polycondensation of a dicarboxylic acid and a diamine and a structural unit in which lactam is ring-opened.

The amorphous polyamide may be either a copolymerized polyamide or a mixed polyamide. As the polyamide, a copolymerized polyamide and a mixed polyamide may be used in combination.
Further, as described later, the amorphous polyamide and the crystalline polyamide may be mixed and used as the mixed polyamide.

The amorphous polyamide is preferably a polyamide having an aromatic ring or an alicyclic structure in the main chain.
Specific examples of amorphous polyamides are isophthalic acid / terephthalic acid / 1,6-hexanediamine / bis (3-methyl-4-aminocyclohexyl) methane polycondensate, terephthalic acid / 2,2,4- Polycondensate of trimethyl-1,6-hexanediamine / 2,4,4-trimethyl-1,6-hexanediamine, weight of isophthalic acid / bis (3-methyl-4-aminocyclohexyl) methane / ω-laurolactam Condensate, polycondensate of isophthalic acid / terephthalic acid / 1,6-hexanediamine, isophthalic acid / 2,2,4-trimethyl-1,6-hexanediamine / 2,4,4-trimethyl-1,6- Hexamethylene polycondensate, isophthalic acid / terephthalic acid / 2,2,4-trimethyl-1,6-hexanediamine / 2,4,4-trimethyl-1,6-hexanediamine polycondensate, isophthalic acid / Examples thereof include a polycondensate of bis (3-methyl-4-aminocyclohexyl) methane / ω-laurolactam, and a polycondensate of isophthalic acid / terephthalic acid / other diamine components. Further, the benzene ring of the terephthalic acid component or the isophthalic acid component constituting these polycondensates is also included in which the benzene ring is replaced with an alkyl group or a halogen atom. Among them, a polycondensate of isophthalic acid / terephthalic acid / 1,6-hexanediamine, a polycondensate of isophthalic acid / terephthalic acid / 1,6-hexanediamine / bis (3-methyl-4-aminocyclohexyl) methane, and terephthal. Polycondensate of acid / 2,2,4-trimethyl-1,6-hexanediamine / 2,4,4-trimethyl-1,6-hexanediamine, or isophthalic acid / terephthalic acid / 1,6-hexanediamine / Bis (3-methyl-4-aminocyclohexyl) methane polycondensate and terephthalic acid / 2,2,4-trimethyl-1,6-hexanediamine / 2,4,4-trimethyl-1,6-hexanediamine A mixture with the polycondensate of the above can be preferably used. Among these, a polycondensate of isophthalic acid / terephthalic acid / 1,6-hexanediamine and a polycondensate of isophthalic acid / terephthalic acid / 1,6-hexanediamine / bis (3-methyl-4-aminocyclohexyl) methane. , Or a mixture thereof can be used more preferably.

Examples of the amorphous polyamide include polyhexamethylene isophthalamide (polyamide 6I), polybis (3-methyl-4-aminohexyl) methaneterephthalamide (polyamide PACMT), and polybis (3-methyl-4-aminohexyl) methane. Isophthalamide (polyamide PACMI), polybis (3-methyl-4-aminohexyl) methanedodecamide (polyamide PACM12), polybis (3-methyl-4-aminohexyl) methanetetradecamide (polyamide PACM14), or these Mixtures are also preferably mentioned.

The crystallinity in the present embodiment means that the temperature is lowered from the molten state to 50 ° C. at a temperature lowering rate of 10 ° C./min in a nitrogen atmosphere using a differential scanning calorimeter (DSC), and then the temperature is raised to 10 ° C./min. It means that the value of the amount of heat of fusion measured by the velocity is larger than 30 J / g.
Further, amorphous (amorphous) in the present embodiment means that the temperature is lowered from the molten state to 50 ° C. at a temperature lowering rate of 10 ° C./min in a nitrogen atmosphere using DSC, and then the temperature is raised to 10 ° C./min. It means that the value of the amount of heat of fusion measured by the velocity is 30 J / g or less.

As the amorphous polyamide, a commercially available product may be used. Examples of commercially available products include "SELAR" manufactured by Mitsui DuPont Polychemical Co., Ltd., "Unitika Nylon 6" manufactured by Unitika Ltd., Rilsan Clear manufactured by Arkema Co., Ltd., and Grillamide TR manufactured by Ems-Chemie Japan Co., Ltd. ..
In the present embodiment, the specific amorphous resin may be used alone or in combination of two or more.

The physical characteristics of the specific amorphous resin will be described.
The molecular weight of the specific amorphous resin is not particularly limited as long as it is easier to melt by heat than the thermoplastic resin coexisting in the resin composition. If the specific amorphous resin is a polyamide, for example, the weight average molecular weight of the polyamide is preferably in the range of 10,000 or more and 300,000 or less, and more preferably in the range of 10,000 or more and 100,000 or less.
Further, the glass transition temperature or the melting temperature (melting point) of the specific amorphous resin is not particularly limited as in the above molecular weight, and it may be easier to thermally melt than the thermoplastic resin coexisting in the resin composition. If the specific amorphous resin is a polyamide, for example, the melting point (Tm) of the polyamide (copolymerized polyamide or mixed polyamide polyamide) is preferably in the range of 100 ° C. or higher and 400 ° C. or lower, and 150 ° C. or higher and 350 ° C. or lower. The range is more preferred.

The content of the specific amorphous resin is preferably 0.1 part by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin, preferably 0.5 mass by mass, from the viewpoint of further improving the impact resistance. It is more preferably 1 part or more and 90 parts by mass or less, and further preferably 1 part by mass or more and 80 parts by mass or less.
When the content of the specific amorphous resin is in the above range, the affinity with carbon fibers is enhanced and the impact resistance is improved.
The content of the specific amorphous resin is the total content of the specific amorphous resin and the crystalline resin containing at least one of the amide bond and the imide bond, which will be described later, from the viewpoint of further improving the impact resistance. It is preferably 10 parts by mass or more and 100 parts by mass or less, more preferably 20 parts by mass or more and 100 parts by mass or less, and further preferably 25 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass. It is particularly preferable that the amount is 45 parts by mass or more and 100 parts by mass or less. When the content of the specific amorphous resin is in the above range, the impact resistance is more excellent.

In particular, when a large amount of the specific amorphous resin is contained in the range of more than 20 parts by mass and 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin, the amount of the compatibilizer is relatively large with respect to the amount of the specific amorphous resin. The amount is reduced, the specific amorphous resin is less likely to spread in the thermoplastic resin, and the tendency to be localized around the carbon fiber is increased. As a result, it is considered that the coating layer made of the specific amorphous resin is formed in a nearly uniform state while being thickened to some extent over the entire circumference of the carbon fiber having a short fiber length. Therefore, the adhesion of the interface between the carbon fiber and the thermoplastic resin is enhanced, and it becomes easy to obtain a resin molded product having excellent mechanical strength, particularly impact resistance.

The content of the specific amorphous resin is preferably proportional to the above-mentioned content of carbon fibers from the viewpoint of effectively expressing the affinity with carbon fibers.
The content of the specific amorphous resin with respect to the mass of the carbon fiber is preferably 0.1% by mass or more and 1,000% by mass or less, and more preferably 1% by mass or more and 150% by mass or less. It is more preferably mass% or more and 120 mass% or less.
When the content of the specific amorphous resin with respect to the mass of the carbon fiber is 0.1% by mass or more, the affinity between the carbon fiber and the specific amorphous resin tends to increase, and when it is 1,000% by mass or less. Resin fluidity is improved.

-A crystalline resin containing at least one of an amide bond and an imide bond (specific crystalline resin)-
From the viewpoint of impact resistance of the obtained resin molded product, the resin composition according to the present embodiment preferably contains a specific amorphous resin and a crystalline resin containing at least one of an amide bond and an imide bond.

The specific crystalline resin is preferably a resin having low compatibility with the thermoplastic resin, specifically, a resin having a solubility parameter (SP value) different from that of the thermoplastic resin.
Here, the difference in SP value between the thermoplastic resin and the crystalline resin containing at least one of the amide bond and the imide bond is preferably 3 or more, preferably 3 or more, from the viewpoint of compatibility between the two and repulsive force between the two. 6 or less is more preferable.

Specific types of the specific crystalline resin include thermoplastic resins containing at least one of an amide bond and an imide bond in the main chain, and specific examples thereof include polyamide (PA), polyimide (PI), and polyamideimide (). PAI), polyetherimide (PEI), polyamino acid and the like can be mentioned.

As the specific crystalline resin, it is preferable that the compatibility with the thermoplastic resin is low and the SP value is different. Therefore, it is preferable to use a thermoplastic resin of a different type from the thermoplastic resin which is the base material.
Of these, crystalline polyamide (PA) is preferable from the viewpoint of further improving impact resistance and excellent adhesion to carbon fibers.

The crystalline polyamide is a structural unit obtained by decomposing dicarboxylic acid and diamine, or a structural unit in which lactam is opened, and has a structural unit containing an aromatic ring other than aramid, or a structural unit not containing an aromatic ring. It may be any of a polyamide having a structure, a structural unit containing an aromatic ring excluding an aramid structural unit, and a polyamide having a structural unit not containing an aromatic ring, but from the viewpoint of improving impact resistance, an aromatic ring excluding an aramid structural unit. A crystalline polyamide having a structural unit containing an aromatic ring and a structural unit not containing an aromatic ring is preferable.

In particular, when a polyamide having a structural unit containing an aromatic ring excluding the aramid structural unit and a structural unit not containing an aromatic ring is applied as the crystalline polyamide, the affinity between the carbon fiber and the thermoplastic resin is both good.
Further, when a polyamide having a structural unit containing an aromatic ring excluding an aramid structural unit and a structural unit not containing an aromatic ring is applied as the crystalline polyamide, the melt viscosity is lowered and the moldability (for example, injection moldability) is also improved. To do. Therefore, it becomes easy to obtain a resin molded product having high appearance quality.

The aromatic ring refers to a monocyclic aromatic ring (cyclopentadiene, benzene) having a 5-membered ring or more, and a condensed ring (naphthalene or the like) in which a plurality of monocyclic aromatic rings having a 5-membered ring or more are condensed. The aromatic ring also includes a heterocycle (pyridine, etc.).
Further, the aramid structural unit indicates a structural unit obtained by a polycondensation reaction between a dicarboxylic acid containing an aromatic ring and a diamine containing an aromatic ring.

Here, examples of the structural unit containing an aromatic ring excluding the aramid structural unit include at least one of the following structural units (1) and (2).
-Structural unit (1):-(-NH-Ar ^1- NH-CO-R ¹ -CO-)-
(In the structural unit (1), Ar ¹ indicates a divalent organic group containing an ^{aromatic ring. R 1} indicates a divalent organic group not containing an aromatic ring.)
-Structural unit (2):-(-NH-R ^2- NH-CO-Ar ² -CO-)-
(In the structural unit (2), Ar ² indicates a divalent organic group containing an ^{aromatic ring. R 2} indicates a divalent organic group not containing an aromatic ring.)

On the other hand, examples of the structural unit not containing an aromatic ring include at least one of the following structural units (3) and (4).
-Structural unit (3):-(-NH-R ^31- NH-CO-R ³² -CO-)-
(In the structural unit (3), R ³¹ indicates a divalent organic group ^{that does not contain an aromatic ring. R 32} indicates a divalent organic group that does not contain an aromatic ring.)
-Structural unit (4):-(-NH-R ^4- CO-)-
(The structural unit (4), R ⁴ represents a divalent organic group not containing an aromatic ring)

In the structural formulas (1) to (3), the "divalent organic group" indicated by each reference numeral is an organic group derived from the divalent organic group of dicarboxylic acid, diamine, or lactam. Specifically, for example, in the structural unit (1), the ^{"divalent organic group containing an aromatic ring" indicated by Ar 1} indicates a residue obtained by removing two amino groups from the diamine, and the "divalent organic group" indicated by R ¹ indicates ". "Aromatic ring-free divalent organic group" indicates a residue obtained by removing two carboxy groups from a dicarboxylic acid. Further, for example, in the structural unit (4), R ⁴ represents "divalent organic group containing no aromatic ring" is sandwiched de When lactam is ring-opened with "NH group" and "CO group" Indicates an organic group.

The crystalline polyamide may be either a copolymerized polyamide or a mixed polyamide. As the polyamide, a copolymerized polyamide and a mixed polyamide may be used in combination.

The copolymerized polyamide in the crystalline polyamide is, for example, a copolymerized polyamide obtained by copolymerizing a first polyamide having a structural unit containing an aromatic ring excluding an aramid structural unit and a second polyamide having a structural unit not containing an aromatic ring. Is.
The mixed polyamide in the crystalline polyamide is, for example, a mixed polyamide containing a first polyamide having an aromatic ring and a second polyamide having no aromatic ring.
Hereinafter, for convenience, the first polyamide may be referred to as "aromatic polyamide" and the second polyamide may be referred to as "aliphatic polyamide".

In the copolymerized polyamide, the ratio of the aromatic polyamide to the aliphatic polyamide (aromatic polyamide / aliphatic polyamide) is 20/80 or more and 99/1 or less (preferably) in terms of mass ratio from the viewpoint of further improving the impact resistance. Is 50/50 or more and 96/4 or less).
On the other hand, in the mixed polyamide, the ratio of the aromatic polyamide to the aliphatic polyamide (aromatic polyamide / aliphatic polyamide) is 20/80 or more and 99/1 or less in terms of mass ratio (from the viewpoint of further improving the impact resistance). It is preferably 50/50 or more and 96/4 or less).

In the aromatic polyamide, the ratio of the structural unit containing the aromatic ring is preferably 80% by mass or more (preferably 90% by mass or more, more preferably 100% by mass or more) with respect to the total structural unit.
On the other hand, in the aliphatic polyamide, the ratio of the structural unit containing no aromatic ring is preferably 80% by mass or more (preferably 90% by mass or more, more preferably 100% by mass or more) with respect to the total structural unit.

Examples of the aromatic polyamide include a condensed polymer of a dicarboxylic acid containing an aromatic ring and a diamine not containing an aromatic ring, a condensed polymer of a dicarboxylic acid not containing an aromatic ring and a diamine containing an aromatic ring, and the like.

Examples of the aliphatic polyamide include a polycondensate of a dicarboxylic acid containing no aromatic ring and a diamine not containing an aromatic ring, and a ring-opened polycondensate of lactam containing no aromatic ring.

Here, examples of the dicarboxylic acid containing an aromatic ring include phthalic acid (terephthalic acid, isophthalic acid, etc.), biphenyldicarboxylic acid, and the like.
Examples of the aromatic ring-free dicarboxylic acid include oxalic acid, adipic acid, suberic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, malonic acid, succinic acid, glutaric acid, pimelic acid, and azelaic acid.
Examples of the diamine containing an aromatic ring include p-phenylenediamine, m-phenylenediamine, m-xylenediamine, diaminodiphenylmethane, and diaminodiphenyl ether.
Examples of diamines that do not contain an aromatic ring include ethylenediamine, pentamethylenediamine, hexamethylenediamine, nonanediamine, decamethylenediamine, and 1,4-cyclohexanediamine.

Examples of lactams that do not contain an aromatic ring include ε-caprolactam, undecane lactam, and lauryl lactam.

Each dicarboxylic acid, each diamine, and each lactam may be used alone or in combination of two or more.

Crystalline aromatic polyamides include MXD6 (condensation polymer of adipic acid and metaxylenediamine), nylon 6T (condensation polymer of terephthalic acid and hexamethylenediamine), and nylon 6I (isophthalic acid and hexamethylenediamine). (Polycondensate), nylon 9T (polycondensate of terephthalic acid and nandiamine), nylon M5T (polycondensate of terephthalic acid and methylpentadiamine) and the like are exemplified.
Commercially available crystalline aromatic polyamides include "MXD6" manufactured by Mitsubishi Gas Chemical Company, "GENESTAR (registered trademark): PA6T" manufactured by Kuraray, "GENESTAR (registered trademark): PA9T" manufactured by Kuraray, and "" by Toyobo Co., Ltd. TY-502NZ: PA6T ”and the like are exemplified.

Nylon 6 (ε-caprolactam ring-opened polycondensate), nylon 11 (undecanlactam ring-opened polycondensate), nylon 12 (lauryllactam ring-opened polycondensate), nylon 66 as crystalline aliphatic polyamides. (Condensation polymer of adipic acid and hexamethylenediamine), nylon 610 (condensation polymer of sebacic acid and hexamethylenediamine) and the like are exemplified.
Commercially available crystalline aliphatic polyamides include DuPont's "Zytel®: 7331J (PA6)" and DuPont's "Zytel®: 101L (PA66)".

The proportion of aromatic rings of the crystalline polyamide (copolymerized polyamide, mixed polyamide) is preferably 1% by mass or more and 55% by mass or less, and more preferably 5% by mass or more and 50% by mass or less from the viewpoint of further improving the impact resistance. It is preferably 10% by mass or more and 40% by mass or less, more preferably.
The ratio of the aromatic ring of the mixed polyamide is the ratio of the aromatic ring to the entire aromatic polyamide and the aliphatic polyamide.

Here, the ratio of the aromatic ring of the crystalline polyamide means the total ratio of the "monocyclic aromatic ring and the condensed ring obtained by condensing the monocyclic aromatic ring" contained in the polyamide. In calculating the ratio of aromatic rings of polyamide, substituents substituted with monocyclic aromatic rings and condensed rings in which monocyclic aromatic rings are condensed are excluded.

That is, the ratio of the aromatic ring of the crystalline polyamide is determined from the molecular weight of the "structural unit in which dicarboxylic acid and diamine are polycondensed" or the "structural unit in which lactam is opened" of the polyamide, and the aromatic contained in this structural unit. It is calculated by the ratio (mass%) of the molecular weight of the ring (if it has a substituent, the aromatic ring excluding the substituent).

First, the proportion of aromatic rings of a typical polyamide is shown below. The proportion of the aromatic rings of nylon 6 and nylon 66 having no aromatic ring is 0% by mass. Meanwhile, MXD6 having an aromatic ring, aromatic ring in the structural unit - for having _"-C 6 _{H 4} (molecular weight 76.10)", the proportion of the aromatic rings is 30.9 wt%. Similarly, the proportion of the aromatic ring of nylon 9T is 26.4% by mass.

-Nylon 6: Structural unit structure "-NH- (CH ₂ ) ₅ -CO-", structural unit molecular weight = 113.16, aromatic ring ratio = 0% by mass
-Nylon 66: Structure of structural unit "-NH- (CH ₂ ) _6- NH-CO- (CH ₂ ) ₄ -CO-", molecular weight of structural unit = 226.32, proportion of aromatic ring = 0% by mass
· MXD6: Structure of the structural unit _{"-NH-CH 2 -C 6 H 4} -CH 2 -NH-CO- (CH 2) 4 -CO- ", the structural unit molecular weight = 246.34, the proportion of the aromatic ring = 30.9% by mass
Nylon 9T: Structural unit structure "-NH- (CH ₂ ) _9- NH-CO-C ₆ H ₄ -CO-", structural unit molecular weight = 288.43, aromatic ring ratio = 26.4% by mass

Then, the ratio of aromatic rings of the copolymerized polyamide and the mixed polyamide is determined as follows.

-Example 1: In the case of a copolymerized polyamide or a mixed polyamide of nylon 6 and MXD6 (mass ratio of nylon 6 and MXD6 = 50/50)-
Ratio of aromatic rings = (ratio of nylon 6 x ratio of aromatic rings in nylon 6) + ratio of MXD6 x ratio of aromatic rings in MXD6) = (0.5 x 0) + (0.5 x 30.9) = 15.5 (mass%)

-Example 2: In the case of a copolymerized polyamide or a mixed polyamide of nylon 66, MXD6 and nylon 9T (mass ratio of nylon 66, MXD6 and nylon 9T = 50/25/25)-
Percentage of aromatic rings = (ratio of nylon 66 x proportion of aromatic rings in nylon 66) + proportion of MXD6 x proportion of aromatic rings in MXD6) + (ratio of nylon 9T x proportion of aromatic rings in nylon 9T) = ( 0.5 x 0.5 x 0) + (0.25 x 30.9) + (0.25 x 26.4) = 14.3 (% by mass)

The molecular weight of the specific crystalline resin is not particularly limited as long as it is easier to melt by heat than the thermoplastic resin coexisting in the resin composition. If the specific crystalline resin is a polyamide, for example, the weight average molecular weight of the polyamide is preferably in the range of 10,000 or more and 300,000 or less, and more preferably in the range of 10,000 or more and 100,000 or less.
Further, the glass transition temperature or the melting temperature (melting point) of the specific crystalline resin is not particularly limited as in the above molecular weight, and it may be easier to thermally melt than the thermoplastic resin coexisting in the resin composition. If the specific crystalline resin is a polyamide, for example, the melting point (Tm) of a polyamide (copolymerized polyamide or mixed polyamide polyamide) is preferably in the range of 100 ° C. or higher and 400 ° C. or lower, and in the range of 150 ° C. or higher and 350 ° C. or lower. Is more preferable.

The total content of the specific amorphous resin and the specific crystalline resin may be 0.1 part by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin from the viewpoint of further improving the impact resistance. It is more preferably 0.5 parts by mass or more and 90 parts by mass or less, and further preferably 1 part by mass or more and 80 parts by mass or less.
When the total content of the specific amorphous resin and the specific crystalline resin is within the above range, the affinity with the carbon fiber is enhanced and the impact resistance is improved.

In particular, when the total content of the specific amorphous resin and the specific crystalline resin is included in a large amount in the range of more than 20 parts by mass and 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin, the total content is increased. The amount of the compatibilizer is relatively small, the specific amorphous resin and the specific crystalline resin are less likely to spread in the thermoplastic resin, and the tendency to localize around the carbon fiber increases. As a result, it is considered that the coating layer of the specific amorphous resin and the specific crystalline resin is formed in a nearly uniform state while being thickened to some extent over the entire circumference of the carbon fiber having a short fiber length. Therefore, the adhesion of the interface between the carbon fiber and the thermoplastic resin is enhanced, and it becomes easy to obtain a resin molded product having excellent mechanical strength, particularly impact resistance.

The total content of the specific amorphous resin and the specific crystalline resin is preferably proportional to the above-mentioned content of the carbon fibers from the viewpoint of effectively expressing the affinity with the carbon fibers.
The total content of the specific amorphous resin and the specific crystalline resin with respect to the mass of the carbon fibers is preferably 0.1% by mass or more and 1,000% by mass or less, and 1% by mass or more and 150% by mass or less. More preferably, it is more preferably 1% by mass or more and 120% by mass or less.
When the total content of the specific amorphous resin and the specific crystalline resin with respect to the mass of the carbon fiber is 0.1% by mass or more, the affinity between the carbon fiber and the specific amorphous resin and the specific crystalline resin. The crystallinity is likely to increase, and when it is 1,000% by mass or less, the resin fluidity is improved.

-Solution agent-
The compatibilizer is a resin that enhances the affinity between the thermoplastic resin and the specific amorphous resin.
The compatibilizer may be determined according to the thermoplastic resin.
The compatibilizer preferably has the same structure as the thermoplastic resin and contains a portion of the molecule having an affinity for the specific amorphous resin.

For example, when polyolefin is used as the thermoplastic resin, modified polyolefin may be used as the compatibilizer.
Here, if the thermoplastic resin is polypropylene (PP), modified polypropylene (PP) is preferable as the modified polyolefin, and similarly, if the thermoplastic resin is ethylene-vinyl acetate copolymer resin (EVA), the modified polyolefin is used. A modified ethylene-vinyl acetate copolymer resin (EVA) is preferable.

Examples of the modified polyolefin include a polyolefin having a modified site containing a carboxy group, a carboxylic acid anhydride residue, a carboxylic acid ester residue, an imino group, an amino group, an epoxy group and the like introduced therein.
The modification site introduced into the polyolefin preferably contains a carboxylic acid anhydride residue from the viewpoint of further improving the affinity between the polyolefin and the specific amorphous resin and the upper limit temperature during molding. In particular, it preferably contains a maleic anhydride residue.

The modified polyolefin can be obtained by reacting a compound containing the above-mentioned modified site with a polyolefin to directly chemically bond the modified polyolefin, or using a compound containing the above-mentioned modified site to form a graft chain and binding the graft chain to the polyolefin. There is.
Examples of the compound containing the above-mentioned modification site include maleic anhydride, fumaric anhydride, citric anhydride, N-phenylmaleimide, N-cyclohexylmaleimide, glycidyl (meth) acrylate, glycidyl vinylbenzoate, and N- [4- (2,2). 3-Epoxypropoxy) -3,5-dimethylbenzyl] acrylamide, alkyl (meth) acrylates, and derivatives thereof.
Among the above, modified polyolefin obtained by reacting maleic anhydride, which is an unsaturated carboxylic acid, with polyolefin is preferable.

Specific examples of the modified polyolefin include maleic anhydride-modified polypropylene, maleic anhydride-modified polyethylene, maleic anhydride-modified ethylene-vinyl acetate copolymer resin (EVA), and acid-modified polyolefins such as adducts or copolymers thereof. ..

As the modified polyolefin, a commercially available product may be used.
Examples of the modified propylene include Youmex (registered trademark) series (100TS, 110TS, 1001, 1010) manufactured by Sanyo Chemical Industries, Ltd.
Examples of the modified polyethylene include Youmex (registered trademark) series (2000) manufactured by Sanyo Chemical Industries, Ltd., Modic (registered trademark) series manufactured by Mitsubishi Chemical Corporation, and the like.
Examples of the modified ethylene-vinyl acetate copolymer resin (EVA) include the Modic (registered trademark) series of Mitsubishi Chemical Corporation.

The molecular weight of the compatibilizer is not particularly limited, but is preferably in the range of 5,000 or more and 100,000 or less, and more preferably in the range of 5,000 or more and 80,000 or less, from the viewpoint of processability.

The content of the compatibilizer is preferably 0.1 part by mass or more and 50 parts by mass or less, more preferably 0.1 part by mass or more and 40 parts by mass or less, and 0 by mass with respect to 100 parts by mass of the thermoplastic resin. It is more preferable that the amount is 1 part by mass or more and 30 parts by mass or less.
The content of the compatibilizer is preferably 1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total content of the specific amorphous resin and the specific crystalline resin, and is 5 parts by mass or more and 50 parts by mass or less. It is more preferable that the amount is 10 parts by mass or more and 50 parts by mass or less.
When the content of the compatibilizer is in the above range, the affinity between the thermoplastic resin and the specific amorphous resin and the specific crystalline resin is enhanced, and the impact resistance is improved.

The content of the compatibilizer is proportional to the total content of the specific amorphous resin and the specific crystalline resin from the viewpoint of increasing the affinity between the thermoplastic resin and the specific amorphous resin and the specific crystalline resin (carbon). Indirectly proportional to the fiber content).
The content of the compatibilizer with respect to the mass of the carbon fiber is preferably 1% by mass or more and 50% by mass or less, more preferably 5% by mass or more and 40% by mass or less, and 10% by mass or more and 30% by mass or less. The following is more preferable.
When the content of the compatibilizer with respect to the mass of the carbon fiber is 1% by mass or more, the affinity between the carbon fiber and the specific amorphous resin and the specific crystalline resin can be easily obtained, and 50% by mass or less (particularly 30% by mass). % Or less), the residual unreacted functional groups that cause discoloration and deterioration are suppressed.

-Other ingredients-
The resin composition according to the present embodiment may contain other components in addition to the above-mentioned components.
Other components include, for example, flame retardants, flame retardants, anti-drip agents when heated, plastic agents, antioxidants, mold release agents, lightfasteners, weatherproofing agents, colorants, pigments, etc. Modifiers, antistatic agents, antioxidants, fillers, reinforcements other than carbon fibers (talc, clay, mica, glass flakes, milled glass, glass beads, crystalline silica, alumina, silicon nitride, aluminum nitride, Well-known additives such as boron nitride, etc.) can be mentioned.
The other components are, for example, 0 parts by mass or more and 10 parts by mass or less, and more preferably 0 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. Here, "0 parts by mass" means a form containing no other components.

(Manufacturing method of resin composition)
The resin composition according to the present embodiment is produced by melt-kneading each of the above components.
Here, as the means for melt-kneading, known means are used, and examples thereof include a twin-screw extruder, a Henschel mixer, a Banbury mixer, a single-screw extruder, a multi-screw extruder, and a conider.
The temperature (cylinder temperature) at the time of melt-kneading may be determined according to the melting point of the resin component constituting the resin composition and the like.

In particular, the resin composition according to the present embodiment is preferably obtained by a production method including a step of melt-kneading a thermoplastic resin, carbon fibers, a specific amorphous resin, and a compatibilizer. When the thermoplastic resin, the carbon fiber, the specific amorphous resin, and the compatibilizer are collectively melt-kneaded, the coating layer of the specific amorphous resin is thin and almost uniform around the carbon fiber. It becomes easier to form and the impact resistance is improved.

[Resin molded product]
The resin molded product according to the present embodiment includes a thermoplastic resin, carbon fibers, a specific amorphous resin, and a compatibilizer. That is, the resin molded product according to the present embodiment has the same composition as the resin composition according to the present embodiment.

The resin molded product according to the present embodiment may be obtained by preparing the resin composition according to the present embodiment and molding the resin composition, or may be a component other than carbon fibers. A composition containing the above may be prepared and obtained by mixing the composition with carbon fiber at the time of molding.
As the molding method, for example, injection molding, extrusion molding, blow molding, hot press molding, calender molding, coating molding, cast molding, dipping molding, vacuum molding, transfer molding and the like may be applied.

The method for molding the resin molded product according to the present embodiment is preferably injection molding because it has a high degree of freedom in shape.
The cylinder temperature for injection molding is, for example, 180 ° C. or higher and 300 ° C. or lower, preferably 200 ° C. or higher and 280 ° C. or lower. The mold temperature for injection molding is, for example, 30 ° C. or higher and 100 ° C. or lower, more preferably 30 ° C. or higher and 60 ° C. or lower.
Injection molding may be performed using commercially available devices such as NEX150 manufactured by Nissei Resin Industry Co., Ltd., NEX300 manufactured by Nissei Resin Industry Co., Ltd., and SE50D manufactured by Sumitomo Heavy Industries, Ltd.

The resin molded product according to the present embodiment is suitably used for applications such as electronic / electrical equipment, office equipment, home appliances, automobile interior materials, and containers. More specifically, housings for electronic / electrical equipment and home appliances; various parts for electronic / electrical equipment and home appliances; interior parts for automobiles; storage cases for CD-ROMs and DVDs; tableware; beverage bottles; food trays Wrap material; film; sheet; etc.
In particular, since the resin molded product according to the present embodiment uses carbon fiber as the reinforcing fiber, it becomes a resin molded product having more excellent mechanical strength, and is therefore suitable for alternative use to metal parts.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

[Examples 1 to 12 and Comparative Examples 1 to 6]
The components according to Table 1 or 2 (the numerical values in the table indicate the number of copies) are kneaded with the following kneading conditions and Table 1 or Table 2 using a twin-screw kneader (manufactured by Toshiba Machine Co., Ltd., TEM58SS). Kneading was performed at the melt-kneading temperature (cylinder temperature) shown in (1) to obtain pellets of the resin composition. The obtained pellets were calcined at 600 ° C. for 2 hours, and the average fiber length of the remaining carbon fibers was measured by the above method. The measurement results are shown in Tables 1 and 2.

-Molding conditions-
・ Screw diameter: φ58mm
・ Rotation speed: 300 rpm
・ Discharge nozzle diameter: 1 mm

The obtained pellets are subjected to an injection molding machine (NEX150, manufactured by Nissei Resin Industry Co., Ltd.) at the injection molding temperature (cylinder temperature) and the mold temperature of 50 ° C. shown in Table 1 or Table 2, and the ISO multipurpose dumbbell test piece. (Corresponding to ISO527 tensile test and ISO178 bending test) (test part thickness 4 mm, width 10 mm) and D2 test piece (length 60 mm, width 60 mm, thickness 2 mm) were molded.

[Evaluation]
The following evaluations were carried out using the obtained two types of test pieces.
The evaluation results are shown in Tables 1 and 2.

− Flexural modulus −
The flexural modulus of the obtained ISO multipurpose dumbbell test piece was measured using a universal test device (manufactured by Shimadzu Corporation, Autograph AG-Xplus) by a method conforming to ISO178.

-Impact resistance (impact resistance)-
Using the obtained ISO multipurpose dumbbell test piece notched (plate thickness 4 mm), Charpy impact strength (kJ / kJ /) was performed by an impact tester (DG-5, manufactured by Toyo Seiki Seisakusho Co., Ltd.) according to the method specified in ISO179. m ² ) was measured. The larger the measured value, the higher the impact resistance and the better the impact resistance.

-Temperature cycle stability-
The ISO multipurpose dumbbell test piece is described in 1. ~ 4. After applying stress for 20 cycles in a temperature cycle environment consisting of the above, the flexural modulus and the impact resistance were measured.
1. 1. -30 ° C x 2 hours 2. Temperature rise from -30 ° C to 80 ° C (10 ° C / min)
3.80 ° C x 2 hours Lower temperature from 4.80 ° C to -30 ° C (10 ° C / min)

-Presence or absence of coating layer-
Using the obtained D2 test piece, the presence or absence of a coating layer made of the specific amorphous resin (and the specific crystalline resin) was confirmed according to the method described above.

The details of the material types shown in Tables 1 and 2 are as follows.
-Thermoplastic resin-
-Polypropylene (Novatec (registered trademark) PP MA3, manufactured by Japan Polypropylene Corporation)

-Reinforcing fiber-
-Carbon fiber A (with surface treatment, chopped carbon fiber Treca (registered trademark), Toray Industries, Inc., average fiber length 20 mm, average diameter 7 μm)
-Carbon fiber B (without surface treatment, the above chopped carbon fiber Torayca (registered trademark), Toray Industries, Inc. was soaked in a solvent to remove the sizing agent)

-Specific amorphous resin: Amorphous PA (amorphous polyamide)-
-SELAR (SELAR (registered trademark) manufactured by Mitsui DuPont Polychemical Co., Ltd., nylon 6I6T, glass transition point: 125 ° C.)
-Rilsan ClearG350 (Arkema's Rilsan ClearG350®, amorphous polyamide derived from bis (3-methyl-4-aminocyclohexyl) methane and 1,14-tetradecandionic acid, glass transition point: 145 ° C. )

-Specific crystalline resin: Aliphatic PA (aliphatic polyamide)-
-PA6 (Nylon 6, Zytel® 7331J, manufactured by DuPont)

-Solution agent-
-Maleic anhydride-modified polypropylene (Youmex (registered trademark) 110TS, manufactured by Sanyo Chemical Industries, Ltd.

From the above results, it can be seen that in this example, a resin molded product having excellent temperature cycle stability can be obtained as compared with the comparative example.
Further, from the above results, it can be seen that in this example, a resin molded product having excellent impact resistance can be obtained as compared with the comparative example.

When the resin molded product produced in each example was analyzed by the above-mentioned method, a layer of the compatibilizer used was interposed between the coating layer and the thermoplastic resin (on the surface of the coating layer). It was confirmed that a layer of compatibilizer was formed).

Claims (12)

With thermoplastic resin
With carbon fiber
Amorphous resins containing at least one of an amide bond and an imide bond,
And compatibilizer, only including,
The thermoplastic resin is polyolefin,
The amorphous resin containing at least one of the amide bond and the imide bond is an amorphous polyamide.
The compatibilizer is a polyolefin in which a modification site containing a carboxy group, a carboxylic acid anhydride residue, or a carboxylic acid ester residue has been introduced.
The content of the thermoplastic resin is 45% by mass or more and 95% by mass or less with respect to the total mass of the resin composition.
The content of the carbon fibers is 0.1 part by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin.
The content of the amorphous resin containing at least one of the amide bond and the imide bond is 0.1 part by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin.
A resin composition in which the content of the compatibilizer is 0.1 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. The resin composition according to claim 1, further comprising a crystalline resin containing at least one of an amide bond and an imide bond. The resin composition according to claim 1 or 2 , wherein the average fiber length of the carbon fibers is 0.1 mm or more and 5.0 mm or less. The total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond is 0.1 part by mass with respect to 100 parts by mass of the thermoplastic resin. The resin composition according to claim 2, which is 100 parts by mass or less. The total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond with respect to the total mass of the carbon fibers is 0.1% by mass or more. The resin composition according to claim 2, which is 1,000% by mass or less. The resin composition according to any one of claims 1 to 5 , wherein the content of the compatibilizer is 1% by mass or more and 50% by mass or less with respect to the total mass of the carbon fibers. With thermoplastic resin
With carbon fiber
Amorphous resins containing at least one of an amide bond and an imide bond,
And compatibilizer, only including,
The thermoplastic resin is polyolefin,
The amorphous resin containing at least one of the amide bond and the imide bond is an amorphous polyamide.
The compatibilizer is a polyolefin in which a modification site containing a carboxy group, a carboxylic acid anhydride residue, or a carboxylic acid ester residue has been introduced.
The content of the thermoplastic resin is 45% by mass or more and 95% by mass or less with respect to the total mass of the resin molded product.
The content of the carbon fibers is 0.1 part by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin.
The content of the amorphous resin containing at least one of the amide bond and the imide bond is 0.1 part by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin.
A resin molded product in which the content of the compatibilizer is 0.1 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. The resin molded product according to claim 7 , further comprising a crystalline resin containing at least one of an amide bond and an imide bond. The resin molded product according to any one of claims 7 or 8 , wherein the average fiber length of the carbon fibers is 0.1 mm or more and 5.0 mm or less. The total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond is 0.1 with respect to 100 parts by mass of the thermoplastic resin. The resin molded body according to claim 8 , which is equal to or more than 100 parts by mass and not more than 100 parts by mass. The total content of the amorphous resin containing at least one of the amide bond and the imide bond and the crystalline resin containing at least one of the amide bond and the imide bond with respect to the total mass of the carbon fibers is 0.1% by mass. The resin molded product according to claim 8 , which is more than 1,000% by mass or less. The parts of the total mass of the carbon fiber, the phase content of solubilizing agent, a resin molded article according to any one of equal to or less than 1 wt% to 50 wt% claims 7 to 11.