JP6868182B2 - 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. Including, a long fiber reinforced polyolefin structure having a length of 3 mm or more. "

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 a resin composition containing a thermoplastic resin, carbon fibers, a resin containing at least one of an amide bond and an imide bond in the main chain, and a resin containing at least one of the amide bond and the imide bond in the main chain. It is an object of the present invention to provide a resin composition capable of obtaining a resin molded product having a high bending elasticity as compared with the case where only the terminal-unmodified polyamide is contained.

The above object is achieved by the following invention.

< 1 >
With thermoplastic resin
With carbon fiber
A terminal sterol-modified resin containing at least one of an amide bond and an imide bond in the main chain and having at least one end of the main chain modified with a sterol residue.
Resin composition containing.

< 2 >
The average fiber length before Symbol carbon fibers is 0.1mm or more 5.0mm or less resin composition according to <1>.

< 3 >
Before Kinetsu thermoplastic resin is a polyolefin <1> or the resin composition according to <2>.

< 4 >
Before SL terminal sterol-modified resin is a polyamide containing an amide bond in the main chain <1> to the resin composition according to any one of <3>.

< 5 >
Before SL content of carbon fiber, the heat is 200 parts by mass or less than 0.1 parts by mass with respect to thermoplastic resin 100 parts by mass <1> to the resin composition according to any one of <4>.

< 6 >
Before SL content of the terminal sterol-modified resin, 100 parts by mass of the thermoplastic resin to at most 100 parts by mass or more 0.1 part by mass <1> to the resin composition according to any one of <5>.

< 7 >
To the mass of pre-SL carbon fiber, the content of the terminal sterol-modified resin is 200 wt% or less than 0.1 wt% <1> to the resin composition according to any one of <6>.

< 8 >
The resin composition according to any one of < 1 > to < 7 > , which contains a compatibilizer.

< 9 >
Before SL compatibilizing agent is a modified polyolefin resin composition according to <8>.

< 10 >
The content of the previous SL compatibilizer, the heat is less than 50 parts by mass or more 0.1 part by mass with respect to thermoplastic resin 100 parts by mass <8> or resin composition according to <9>.

< 11 >
The content of the previous SL compatibilizer, said distal sterol relative modified resin 100 parts by mass or less 50 parts by mass or more 1 part by weight <8> ~ resin composition according to any one of <10>.

< 12 >
To the mass of pre-SL carbon fiber content of the compatibilizer is less than 50 mass% 1 mass% or more <8> ~ resin composition according to any one of <11>.

< 13 >
With thermoplastic resin
With carbon fiber
A terminal sterol-modified resin containing at least one of an amide bond and an imide bond in the main chain and having at least one end of the main chain modified with a sterol residue.
Resin molded body containing.

< 14 >
Resin molded article according to the average fiber length before the SL carbon fiber is 0.1mm or more 5.0mm or less <13>.

< 15 >
Before Kinetsu thermoplastic resin is a polyolefin <13> or resin molded product according to <14>.

< 16 >
Before SL terminal sterol-modified resin is a polyamide containing an amide bond in the main chain <13> ~ resin molded article according to any one of <15>.

< 17 >
Before SL content of carbon fibers, the thermoplastic resin is not more than 200 parts by mass 0.1 parts by mass per 100 parts by mass <13> ~ resin molded article according to any one of <16>.

< 18 >
Before SL content of the terminal sterol-modified resin, 100 parts by mass of the thermoplastic resin to at most 100 parts by mass or more 0.1 part by mass <13> ~ resin molded article according to any one of <17>.

< 19 >
To the mass of pre-SL carbon fiber content of the end sterol-modified resin is not more than 200 mass% to 0.1 mass% <13> ~ resin molded article according to any one of <18>.

< 20 >
The resin molded product according to any one of < 13 > to < 19 > , which contains a compatibilizer.

< 21 >
Before SL compatibilizer, a resin molded article according to a modified polyolefin <20>.

< 22 >
Before SL phase content of solubilizing agent, the heat is less than 50 parts by mass or more 0.1 part by mass with respect to thermoplastic resin 100 parts by mass <20> or resin molded article according to <21>.

< 23 >
Before SL phase content of solubilizing agent, the terminal sterol-modified resin 100 parts by mass with respect to at most 50 parts by mass 1 part by mass or more <20> - resin molded article according to any one of <22>.

< 24>
To the mass of pre-SL carbon fiber content of the compatibilizer is less than 50 mass% 1 mass% or more <20> - resin molded article according to any one of <23>.

According to the inventions according to < 1 > , < 3 > , and < 4 > , in a resin composition containing a thermoplastic resin, carbon fibers, and a resin containing at least one of an amide bond and an imide bond in the main chain, the amide bond And a resin composition capable of obtaining a resin molded body having a high bending elasticity as compared with the case where only the terminal-unmodified polyamide is contained as the resin containing at least one of the imide bonds in the main chain is provided.
According to the invention according to < 2 > , a thermoplastic resin, carbon fibers, and a resin containing at least one of an amide bond and an imide bond in the main chain are included, and the average fiber length of the carbon fibers is 0.1 mm or more and 5.0 mm or less. The resin composition is a resin composition capable of obtaining a resin molded body having a higher bending elasticity as compared with the case where only the terminal-unmodified polyamide is contained as the resin containing at least one of the amide bond and the imide bond in the main chain. Is provided.
According to the invention according to < 5 > , a resin molded product having a higher flexural modulus than 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 < 6 > , a resin having a higher flexural modulus than the case where the content of the terminal sterol-modified resin is less than 0.1 part by mass or more than 100 parts by mass with respect to 100 parts by mass of the thermoplastic resin. A resin composition for obtaining a molded product is provided.
According to the invention according to < 7 > , the resin molded product having a higher flexural modulus than the case where the content of the terminal sterol-modified resin with respect to the mass of the carbon fiber is less than 0.1% by mass or more than 200% by mass The resulting resin composition is provided.
According to the invention according to < 8 > , a resin composition capable of obtaining a resin molded product having a higher flexural modulus as compared with the case where it contains a thermoplastic resin, carbon fibers, and a terminal sterol-modified resin and does not contain a compatibilizer. Things are provided.
According to the invention according to < 9 >, there is provided a resin composition capable of obtaining a resin molded product having a higher flexural modulus as compared with the case where an epoxy copolymer is used as a compatibilizer.
According to the invention according to < 10 > , resin molding having a higher flexural modulus than 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 < 11 > , a resin molded product having a higher flexural modulus than when the content of the compatibilizer is less than 1 part by mass or more than 50 parts by mass with respect to 100 parts by mass of the terminal sterol-modified resin. Is provided.
According to the invention according to < 12 > , a resin capable of obtaining a resin molded product having a high flexural modulus as compared with the case where the content of the compatibilizer with respect to the mass of the carbon fiber is less than 1% by mass or more than 50% by mass. The composition is provided.

According to the inventions of < 13 > , < 15 > , and < 16 > , in a resin molded product containing a thermoplastic resin, carbon fibers, and a resin containing at least one of an amide bond and an imide bond in the main chain, the amide bond is formed. And a resin molded product having a higher bending elasticity than the case where only the terminal-unmodified polyamide is contained as the resin containing at least one of the imide bond in the main chain is provided.
According to the invention according to < 14 > , a thermoplastic resin, carbon fibers, and a resin containing at least one of an amide bond and an imide bond in the main chain are included, and the average fiber length of the carbon fibers is 0.1 mm or more and 5.0 mm or less. In the resin molded body, the resin molded body has a higher bending elasticity as compared with the case where only the terminal-unmodified polyamide is contained as the resin containing at least one of the amide bond and the imide bond in the main chain.
According to the invention according to < 17 > , a resin molded product having a higher flexural modulus than 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 < 18 > , a resin having a high flexural modulus as compared with the case where the content of the terminal sterol-modified resin is less than 0.1 part by mass or more than 100 parts by mass with respect to 100 parts by mass of the thermoplastic resin. A molded body is provided.
According to the invention according to < 19 > , the resin molded product having a high flexural modulus is higher than that in the case where the content of the terminal sterol-modified resin with respect to the mass of the carbon fiber is less than 0.1% by mass or more than 200% by mass. Provided.
According to the invention of < 20 > , a resin molded product containing a thermoplastic resin, carbon fibers, and a terminal sterol-modified resin and having a higher flexural modulus as compared with the case where no compatibilizer is contained is provided.
According to the invention according to < 21 > , a resin molded product having a higher flexural modulus is provided as compared with the case where an epoxy copolymer is used as a compatibilizer.
According to the invention according to < 22 > , resin molding having a higher flexural modulus than when 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 < 23 > , a resin molded body having a higher flexural modulus than the case where the content of the compatibilizer is less than 1 part by mass or more than 50 parts by mass with respect to 100 parts by mass of the terminal sterol-modified resin. Is provided.
According to the invention according to < 24 > , a resin molded product having a higher flexural modulus is provided as compared with the case where the content of the compatibilizer with respect to the mass of the carbon fiber is less than 1% by mass or more than 50% by mass. ..

It is a schematic diagram for demonstrating an example of the main part of the resin molded article which concerns on this embodiment. It is a schematic diagram for demonstrating another 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, and at least one of an amide bond and an imide bond in the main chain, and at least one end of the main chain is modified with a sterol residue. Includes sterol-modified resin.

In the present specification, the "sterol residue" refers to a sterol (steroid alcohol) having a hydroxyl group (-OH), a resin containing at least one of an amide bond and an imide bond in the main chain and having a functional group at the end. Represents a sterol residue (that is, a group obtained by removing a hydroxyl group (-OH) from a sterol) bonded to the end of the resin by the reaction of.
Further, the "cholesterol residue" is a residue of cholesterol bound to the end of the resin by reacting with cholesterol and a resin having at least one of an amide bond and an imide bond in the main chain and having a functional group at the end. Represents a group (that is, a group obtained by removing a hydroxyl group (-OH) from cholesterol).

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.
In such a resin composition, if the affinity between the reinforcing fiber and the thermoplastic resin is low, a space is formed at the interface between the reinforcing fiber and the thermoplastic resin, and the adhesion at the interface may be lowered.
In particular, when carbon fiber is used as the reinforcing fiber in the resin composition, higher mechanical strength is required than that of glass fiber or the like. Therefore, the decrease in adhesion at the interface between the carbon fiber and the thermoplastic resin is caused by the machine. It may cause a decrease in the target strength, especially the flexural modulus.
In particular, when carbon fiber is used as the reinforcing fiber in the resin composition, higher mechanical strength is required as compared with glass fiber and the like, but it contributes to adhesion to thermoplastic resins such as hydroxyl groups and carboxyl groups on the surface of carbon fiber. Since the number of polar groups formed is smaller than that of glass fiber, the adhesion at the interface between the carbon fiber and the thermoplastic resin is lowered. As a result, the mechanical strength, particularly the flexural modulus, is unlikely to increase for the composition of the carbon fibers. In particular, when a load of repeated bending is applied, peeling at the interface between the carbon fiber and the thermoplastic resin tends to proceed, so that the bending elastic modulus tends to decrease significantly from the initial stage.

Therefore, the resin composition according to the present embodiment contains three components of a thermoplastic resin, carbon fibers, and a terminal sterol-modified resin.
With this configuration, a resin molded body having a high flexural modulus can be obtained. The action to obtain such an effect is not clear, but it is presumed as follows.

When a resin molded product is obtained from the resin composition according to the present embodiment, when the resin composition is thermally melt-mixed, the thermoplastic resin as the base material and the sterol residue contained at the end of the main chain of the terminal sterol-modified resin are obtained. The two are compatible with each other, and the terminal sterol-modified resin is dispersed in the resin composition.
In this state, when the terminal sterol-modified resin comes into contact with the carbon fiber, a large number of amide bonds or imide bonds contained along the molecular chain of the terminal sterol-modified resin, and a polar group slightly present on the surface of the carbon fiber, Physically adheres at multiple points due to affinity (attraction and hydrogen bonding). Since the steroid structure is easy to crystallize, the sterol residue has high crystallinity, and the thermoplastic resin used as the base material also generally has high crystallinity. Therefore, the sterol residue at the terminal has an affinity with the thermoplastic resin. Excellent for. Therefore, even when the main chain is physically adhered to the surface of the carbon fiber, the sterol residue at the end is oriented from the surface of the carbon fiber toward the thermoplastic resin as the base material due to the above affinity. Exists in a state. In this way, a coating layer made of the terminal sterol-modified 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 sterol residue is oriented outward (that is, in the thermoplastic resin as the base material) from the terminal sterol-modified resin forming the coating layer, and this sterol residue is also compatible with the thermoplastic resin. Therefore, an equilibrium state between the attractive force and the repulsive force is formed, and the coating layer made of the terminal sterol-modified 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 terminal sterol-modified resin, a coating layer made of the terminal sterol-modified resin is formed around the carbon fiber. It is considered that the coating layer is easy to be formed, is thin, and has excellent uniformity.

The coating layer preferably covers the entire periphery of the carbon fiber, but there may be a partially uncoated portion.

From the above, it is presumed that the resin composition according to the present embodiment has improved adhesion at the interface between the carbon fiber and the thermoplastic resin, and can obtain a resin molded product having mechanical strength, particularly a high flexural modulus. To.

The steroid structure is a nucleating material and a crystallization material for thermoplastic resin. Therefore, by preparing a resin composition containing a terminal sterol-modified resin having a sterol residue at the terminal, it is effective in shortening the curing tact during injection molding, and high throughput of injection molding can be achieved.

Further, the resin composition according to the present embodiment contains three components of a thermoplastic resin, carbon fibers, and a resin having at least one of an amide bond and an imide bond in the main chain, and the amide bond and the imide bond thereof. As a resin containing at least one of the above in the main chain, a terminal sterol-modified resin in which at least one end of the main chain is modified with a sterol residue is contained. In the resin composition containing the above three components, a resin molded product having excellent impact resistance as compared with the case where only the terminal-unmodified polyamide is contained as the resin containing at least one of the amide bond and the imide bond in the main chain. Is obtained as a resin composition. The action to obtain such an effect is not clear, but it is presumed as follows.

Usually, in order to improve the elastic modulus of a resin, a method of firmly immobilizing the molecular structure by chemical bonds between functional groups contained in the resin is effective. In particular, it is said that the elastic modulus can be greatly increased by forming a network-like structure by forming a large number of cross-linking points between polymer chains. However, if a strong impact force is instantly applied to a resin having a strongly bonded crosslinked structure, the crosslinked structure may be destroyed, that is, it is easy to achieve both high elastic modulus and impact resistance in the resin. Not.
On the other hand, in the resin composition according to the present embodiment, the terminal sterol residue in the terminal sterol-modified resin is mixed (affinity) with the thermoplastic resin with a relatively weak binding force. Therefore, even if an impact is applied instantaneously, the impact force can be diffused by relaxing the internal structure, so that the impact resistance can be improved while obtaining a high elastic modulus (especially high flexural modulus). it is conceivable that.

Here, the resin composition according to the present embodiment and the resin molded product obtained by the resin composition are subjected to terminal sterol modification around the carbon fibers by hot melt kneading and injection molding during the production of the resin composition (for example, pellets). It is preferable that the coating layer made of resin is formed and has a structure in which the thickness of the coating layer is 5 nm or more and 700 nm or less.

In the resin composition according to the present embodiment, the thickness of the coating layer made of the terminal sterol-modified resin is 5 nm or more and 700 nm or less, and is preferably 10 nm or more and 650 nm or less from the viewpoint of further improving the flexural modulus. When the thickness of the coating layer is 5 nm or more (particularly 10 nm or more), the flexural modulus 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 flexural modulus 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.

-Layer of compatibilizer In the resin composition (and its resin molded product) according to the present embodiment, for example, the compatibilizer may be partially compatible between the coating layer and the thermoplastic resin. Good.
Specifically, for example, a layer of a compatibilizer may be interposed between the coating layer made of the terminal sterol-modified resin and the thermoplastic resin which is the base material (see FIG. 2). That is, a layer of the compatibilizer may be formed on the surface of the coating layer, and the coating layer and the thermoplastic resin may be adjacent to each other via the layer of the compatibilizer. The layer of the compatibilizer is formed thinner than the coating layer, but the interposition of the compatibilizer layer enhances the adhesion (adhesiveness) between the coating layer and the thermoplastic resin, and mechanical strength, especially the flexural modulus. 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 compatibilizer layer is bonded to the coating layer (hydrogen bond, covalent bond by the reaction of the functional group between the compatibilizer and the terminal sterol-modified resin, etc.) and is compatible with the thermoplastic resin. It may be 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 terminal sterol-modified resin described above in the molecule. It is easy to realize by applying a compatibilizer containing a site.
Specifically, for example, when polyolefin is applied as a thermoplastic resin, polyamide in which at least one end of the main chain is modified with a sterol residue as a terminal sterol-modified resin, and maleic anhydride-modified polyolefin as a compatibilizer is applied. In the layer of maleic anhydride-modified polyolefin (layer of 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 layer. It is preferable that the polyolefin moiety is interposed in a state of being compatible with the polyolefin.

Here, the method for confirming that the layer of the compatibilizer is interposed between the coating layer and the thermoplastic resin is as follows.
A micro-infrared spectroscopic analyzer (JASCO IRT-5200) is used as the analyzer. For example, a resin composition (or resin molded product) of polypropylene (hereinafter PP) as a thermoplastic resin, terminal steroid-modified PA66 as a terminal sterol-modified resin, and maleic acid-modified polypropylene (hereinafter MA-PP) as a modified polyolefin. In the case, a slice piece is cut out from this resin composition (or resin molded body), and the cross section thereof is observed. Performs IR mapping for the covering layer section surrounding the carbon fiber cross section, to verify the maleic anhydride derived from a layer of the coating layer and the compatibilizer (1820 cm ^-1 or 1750 cm ^-1 or less). Further, to confirm the amide groups derived from the terminal steroid-modified PA66 in the coating layer portion (1680 cm ^-1 or 1630 cm ^-1 or less) and a secondary amino group (3320 cm ^-1 or 3140cm ^-1 or less). As a result, it can be confirmed that the coating 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 reacts with terminal steroid-modified PA66, the cyclic maleinated portion of MA-PP opens and the amine residue of terminal steroid-modified PA66 chemically bonds to the cyclic maleated portion. It can be confirmed that a layer of the compatibilizer (bonding layer) is interposed between the coating layer and the thermoplastic resin.

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

-Thermoplastic resin (A)-
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 stereide (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) ), Polyvinylidene fluoride (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 flexural modulus 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 fibers is short, a resin molded body having a high flexural modulus can be obtained. Therefore, the average fiber length of the carbon fibers 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 fiber 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 flexural modulus, tends to decrease.
However, even if the resin molded product 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 product having a high flexural modulus 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 hungred resin).
When this abbreviation is used, the content of the carbon fiber is 0.1 phr or more and 200 phr or less.

-Terminal sterol modified resin-
The terminal sterol-modified resin is a resin in which the main chain contains at least one of an amide bond and an imide bond, and at least one end of the main chain is modified with a sterol residue. As described above, this terminal sterol-modified resin is a resin that can coat the periphery of carbon fibers.
This terminal sterol-modified resin will be described in detail.

-Terminal modification In a terminal sterol-modified resin, at least one end of the main chain is modified with a sterol residue.
Sterols are also called steroid alcohols and are compounds whose basic skeleton is the structure shown below. In this embodiment, naturally occurring sterols or synthetic sterols may be used.

Sterols have a hydroxyl group (-OH) as shown above. This hydroxyl group is a functional group in a resin having at least one of an amide bond and an imide bond in the main chain and having a functional group at the end (for example, an unmodified product of a resin containing at least one of the amide bond and the imide bond in the main chain). By the reaction, a sterol residue (that is, a group obtained by removing a hydroxyl group (−OH) from sterol) is introduced into the terminal of the terminal sterol-modified resin.
For example, when the resin serving as the main chain is polyamide, polyimide, or the like, since it has a carboxy group (including an anhydride) at the terminal, the hydroxyl group of sterol reacts with such a functional group, thereby causing the sterol to react. A terminal sterol-modified resin is obtained.

Compounds (raw materials) used for terminal modification, that is, sterols, include, for example, cholesterol, β-cytosterol, campesterol, stigmasterol, brush casterol, androsterone, β-cholesterol, corticosterone acetate, dehydroepiandrosterone, epiandro Examples thereof include sterone, elsterol, estrone, 11α-hydroxymethyltestosterone, 11α-hydroxyprogesterone, lanosterol, mestranol, methyltestosterone, Δ9 ⁽¹¹⁾ -methyltestosterone, noretisterone, pregusterone, and testosterone.
Among these, cholesterol and β-cholesterol are preferable, and cholesterol is more preferable, from the viewpoint of improving the flexural modulus.
The chemical structural formulas of typical ones are shown below.

The terminal modification method, that is, the method of reacting the unmodified product of the resin to be the main chain with the compound (sterol) used for the terminal modification is not particularly limited, and a known method can be adopted.

In the terminal sterol-modified resin, the ratio of the number of terminals modified with sterol residues to the total number of terminals (terminal modification rate = number of terminals modified with sterol residues / total number of terminals × 100 [%]) is 10 It is preferably in the range of% or more and 100% or less, more preferably in the range of 30% or more and 100% or less, and further preferably in the range of 50% or more and 80% or less.
When the terminal modification rate is 10% or more (more preferably 30% or more, still more preferably 50% or more), the flexural modulus is more likely to be improved. On the other hand, when the terminal denaturation rate is 100% or less (more preferably 80% or less), the advantage of excellent impact resistance can be obtained.

The above-mentioned terminal denaturation rate can be measured by the following method.
The composition ratio constituting the terminal sterol-modified resin is determined by hydrolyzing the terminal sterol-modified resin, separating it into a dicarboxylic acid, a diamine, and a compound (sterol) used for terminal modification and quantifying it. The total number of terminals is calculated from the equivalent ratio of dicarboxylic acid to diamine, and the number of sealed terminals (modified terminals) is calculated from the amount of the compound used for terminal modification.

-Main chain Next, the main chain of the terminal sterol-modified resin will be described.
The terminal sterol-modified resin contains at least one of an amide bond and an imide bond in the main chain.
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 resin (unmodified product) that becomes the main chain of the terminal sterol-modified resin include thermoplastic resins that contain at least one of an amide bond and an imide bond in the main chain, and specifically, polyamide (a polyamide (unmodified product). PA), polyimide (PI), polyamideimide (PAI), polyetherimide (PEI), polyamino acid and the like can be mentioned.

The terminal sterol-modified resin is preferably a resin having low compatibility with the thermoplastic resin (base material in the resin composition), 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 terminal sterol-modified resin is preferably 3 or more, and more preferably 3 or more and 6 or less in terms of compatibility between the two and repulsive force between the two.
The SP value referred to here is a value calculated by the Fedor method. Specifically, the solubility parameter (SP value) is, for example, Polymer. 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.

As the terminal sterol-modified resin, it is preferable that the compatibility with the thermoplastic resin (base material in the resin composition) is low and the SP value is different. Therefore, a different type of thermoplastic resin from the thermoplastic resin as the base material is used. It is preferable to use it.
Among them, polyamide (PA) is preferable as the resin (unmodified product) that becomes the main chain of the terminal sterol-modified resin from the viewpoint of further improving the flexural modulus 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 lactam. That is, examples of the polyamide include a polyamide having at least one of a structural unit obtained by polycondensing a dicarboxylic acid and a diamine and a structural unit in which lactam is ring-opened.

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, and a polyamide having a structural unit not containing an aromatic ring. , A polyamide having a structural unit containing an aromatic ring excluding an aramid structural unit and a structural unit not containing an aromatic ring may be used, but from the viewpoint of improving the bending elasticity, the fragrance ring excluding the aramid structural unit is included. A polyamide having a structural unit and a structural unit that does not contain 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 polyamide, the affinity between the carbon fiber and the thermoplastic resin is both good. Here, a polyamide having only a structural unit containing an aromatic ring tends to have a higher affinity with carbon fibers and a lower affinity with a thermoplastic resin than a polyamide having only a structural unit without an aromatic ring. A polyamide having only a structural unit containing no aromatic ring tends to have a lower affinity with carbon fibers and a higher affinity with a thermoplastic resin than a polyamide having only a structural unit containing an aromatic ring. Therefore, by applying a polyamide having both structural units, both the affinity between the carbon fiber and the thermoplastic resin becomes good, and the adhesion of the interface between the carbon fiber and the thermoplastic resin is further enhanced by the coating layer of the polyamide. become. Therefore, it becomes easy to obtain a resin molded product having mechanical strength, particularly a high flexural modulus.

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 polyamide, the melt viscosity is lowered and the moldability (for example, injection moldability) is also improved. Therefore, it becomes easy to obtain a resin molded product having high appearance quality.
When a polyamide having only an aramid structural unit is applied as the polyamide, thermal deterioration of the thermoplastic resin is caused at a high temperature at which the polyamide can be melted. Further, at a temperature at which thermal deterioration of the thermoplastic resin is caused, the polyamide cannot be sufficiently melted, the moldability (for example, injection moldability) is deteriorated, and the appearance quality and mechanical performance of the obtained resin molded product are deteriorated.

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 polycondensation reaction of 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 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. Among these, as the polyamide, a mixed polyamide is preferable from the viewpoint of further improving the bending elasticity.

The copolymerized 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.
The mixed 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 bending elasticity. 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 bending elasticity. 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, and a condensed polymer of a dicarboxylic acid containing no aromatic ring and a diamine containing an aromatic ring.

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.

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

Examples of the aliphatic polyamide include nylon 6 (ε-caprolactam ring-opening polycondensate), nylon 11 (undecanlactam ring-opening polycondensate), nylon 12 (lauryllactam ring-opening polycondensate), and nylon 66 (adipin). (Condensation polymer of acid and hexamethylenediamine), nylon 610 (condensation polymer of sebacic acid and hexamethylenediamine) and the like are exemplified.
Commercially available aliphatic polyamide products include DuPont's "Zytel (registered trademark): 7331J (PA6)" and DuPont's "Zytel (registered trademark): 101L (PA66)".

-Physical characteristics The physical characteristics of the terminal sterol-modified resin will be explained.
The molecular weight of the terminal sterol-modified resin is not particularly limited, and it is sufficient that the terminal sterol-modified resin is more easily melted by heat than the thermoplastic resin coexisting in the resin composition. If the terminal sterol-modified resin is a polyamide, for example, the weight average molecular weight of the terminal sterol-modified resin 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 terminal sterol-modified resin is not particularly limited as in the above molecular weight, and may be easier to melt than the thermoplastic resin coexisting in the resin composition. If the terminal sterol-modified resin is a polyamide, for example, the melting point (Tm) of the terminal sterol-modified resin (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 higher. The range of ° C. or lower is more preferable.

The content of the terminal sterol-modified resin is preferably 0.1 part by mass or more and 100 parts by mass or less, and 0.5 parts by mass or more, with respect to 100 parts by mass of the thermoplastic resin, from the viewpoint of further improving the bending elasticity. It is more preferably 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 terminal sterol-modified resin is in the above range, the affinity with carbon fibers is enhanced and the flexural modulus is improved.

In particular, when a compatibilizer is used in combination, if a large amount of the terminal sterol-modified resin is contained in a 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, it is relative to the amount of the terminal sterol-modified resin. The amount of the compatibilizer is reduced, the terminal sterol-modified resin is less likely to spread in the thermoplastic resin, and the tendency to be localized around the carbon fibers is increased. As a result, it is considered that the coating layer made of the terminal sterol-modified 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 mechanical strength, particularly a high flexural modulus.

The content of the terminal sterol-modified 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 terminal sterol-modified resin with respect to the mass of the carbon fiber is preferably 0.1% by mass or more and 200% by mass or less, more preferably 1% by mass or more and 150% by mass or less, and 1% by mass or more. It is more preferably 120% by mass or less.
When the content of the terminal sterol-modified 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 terminal sterol-modified resin tends to increase, and when it is 200% by mass or less, the resin fluidity becomes high. improves.

Here, the adhesion between the terminal sterol-modified resin and the carbon fiber is evaluated by an index such as interfacial shear strength.

-Solution agent-
In the present embodiment, in addition to the three components of the thermoplastic resin, the carbon fiber, and the terminal sterol-modified resin, a compatibilizer may be further used in combination.
The compatibilizer is a resin that enhances the affinity between the thermoplastic resin and the terminal sterol-modified 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 terminal sterol-modified 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), the modified polypropylene (PP) is preferable as the modified polypropylene, 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 in which a modification 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 has been introduced.
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 terminal sterol-modified resin and the upper limit temperature during molding. , Preferably contains maleic anhydride residues.

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, more preferably 5 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the terminal sterol-modified resin, and 10 parts by mass or more. It is more preferably 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 terminal sterol-modified resin is enhanced, and the flexural modulus can be improved.

The content of the compatibilizer may be proportional to the content of the terminal sterol-modified resin (indirectly proportional to the content of carbon fibers) from the viewpoint of increasing the affinity between the thermoplastic resin and the terminal sterol-modified resin. preferable.
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 1% by mass or more and 40% by mass or less, and 1% 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 terminal sterol-modified resin can be easily obtained, and when it is 50% by mass or less (particularly 30% by mass or less). Remaining 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, weathering agents, colorants, pigments, etc. Modifiers, antistatics, 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, preferably 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 terminal sterol-modified resin, and if necessary, a compatibilizer. .. When the thermoplastic resin, the carbon fibers, the terminal sterol-modified resin, and the compatibilizer, if necessary, are melt-kneaded together, the coating layer of the terminal sterol-modified resin is thin and nearly uniform around the carbon fibers. It becomes easy to be formed with, and the flexural modulus increases.

[Resin molded product]
The resin molded product according to the present embodiment includes a thermoplastic resin, carbon fibers, and a terminal sterol-modified resin. 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 a commercially available device such as NEX150 manufactured by Nissei Resin Industry Co., Ltd., NEX300 manufactured by Nissei Resin Industry Co., Ltd., SE50D manufactured by Sumitomo Machinery Co., Ltd., or the like.

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.

-Synthesis of terminal sterol-modified resin-
(Synthesis Example 1: Terminal Sterol Modified Resin 1 (Terminal Sterol Modified PA66))
Hexamethylenediamine (diamine component) 11.27 kg (97 mol), adipic acid (dicarboxylic acid component) 14.61 kg (100 mol), cholesterol (sterol used for terminal denaturation) 1.86 kg (4.8 mol), dia as a catalyst 10 g of sodium phosphate and 18 kg of ion-exchanged water were charged into a 50 liter autoclave _{, pressurized with N 2} from normal pressure to 0.05 MPa, and then released to return to normal pressure. This operation was performed three times to perform N ₂ substitution, and then the mixture was dissolved at 135 ° C. and 0.3 MPa with stirring. Then, the solution was continuously supplied by a liquid feed pump, heated to 240 ° C. by a heating pipe, and heated for 1 hour. Then, the reaction mixture was supplied to the pressurized reaction can, heated to 300 ° C., and a part of water was distilled off so as to maintain the pressure inside the can at 3 MPa to obtain a condensate. Then, this condensate was added to hot water, washed, frozen in liquid nitrogen, and pulverized with a hammer. The obtained resin powder was dried at 120 ° C. for 12 hours to obtain a terminal sterol-modified resin 1 (terminal sterol-modified PA66) having a cholesterol residue at the terminal.
The terminal modification rate of the obtained terminal thrall-modified resin 1 was measured by the above-mentioned method and found to be 80%.

(Synthesis Example 2: Terminal Sterol Modified Resin 2 (Terminal Sterol Modified MXD6))
Same as Synthesis Example 1 except that the dicarboxylic acid component was changed to 14.61 kg (100 mol) of adipic acid, the diamine component was changed to 13.21 kg (97 mol) of m-xylylenediamine, and the sterol was changed to 1.86 kg (4.8 mol) of cholesterol. A terminal sterol-modified resin 2 (terminal sterol-modified MXD6) having a cholesterol residue at the terminal was obtained.
The terminal modification rate of the obtained terminal sterol-modified resin 2 was measured by the above-mentioned method and found to be 80%.

(Synthetic Example 3: Terminal Sterol Modified Resin 3 (Terminal Sterol Modified PA66))
Synthesis Example 1 except that the dicarboxylic acid component was changed to 14.61 kg (100 mol) of adipic acid, the diamine component was changed to 11.27 kg (97 mol) of hexamethylenediamine, and the sterol was changed to 1.99 kg (4.8 mol) of β-sitosterol. In the same manner as above, a terminal sterol-modified resin 3 (terminal sterol-modified PA66) having a β-sitosterol residue at the terminal was obtained.
The terminal modification rate of the obtained terminal sterol-modified resin 3 was measured by the above-mentioned method and found to be 80%.

(Synthetic Example 4: Terminally Modified Resin 4 (Terminal Modified MXD6))
Synthesis Example 1 except that the dicarboxylic acid component was changed to 14.61 kg (100 mol) of adipic acid, the diamine component was changed to 13.21 kg (97 mol) of m-xylylenediamine, and the sterol was changed to 1.99 kg (4.8 mol) of β-sitosterol. In the same manner as above, a terminal sterol-modified resin 4 (terminal-modified MXD6) having a β-sitosterol residue at the terminal was obtained.
The terminal modification rate of the obtained terminal sterol-modified resin 4 was measured by the above-mentioned method and found to be 80%.

[Examples 1 to 22, Comparative Examples 1 to 19]
The components according to Tables 1 to 7 (the numerical values in the table indicate the number of copies) are kneaded in a twin-screw kneader (manufactured by Toshiba Machine Co., Ltd., TEM58SS) under the following kneading conditions and melt kneading shown in Tables 1 to 7. Kneading was performed at a temperature (cylinder temperature) 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 to 7.

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

The obtained pellets are subjected to an injection molding machine (manufactured by NISSEI PLASTIC INDUSTRIES, NEX150) at the injection molding temperature (cylinder temperature) shown in Tables 1 to 7 and the mold temperature of 50 ° C. A D2 test piece (length 60 mm, width 60 mm, thickness 2 mm) was formed into a test (corresponding to the ISO178 bending test) (test portion thickness 4 mm, width 10 mm).

[Evaluation]
The following evaluations were carried out using the obtained two types of test pieces.
The evaluation results are shown in Tables 1 to 7.

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

-Charpy impact strength without notch (impact resistance)-
Using the obtained ISO multipurpose dumbbell test piece, in accordance with JIS-K7111 (2006), with an evaluation device (DG-UB2 manufactured by Toyo Seiki Co., Ltd.) at 23 ° C. The impact strength (kJ / m ² ) was measured.

-Presence or absence of coating layer-
Using the obtained D2 test piece, the presence or absence of a coating layer with a terminal sterol-modified resin was confirmed according to the method described above.

The details of the material types in Tables 1 to 7 are as follows.
-Thermoplastic resin-
-Polypropylene (Novatec (registered trademark) PP MA3, manufactured by Japan Polypropylene Corporation)
-Polyethylene (Ultozex 20100J, made by Prime Polymer Co., Ltd.)

-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 Treca (registered trademark), Toray Industries, Inc. was soaked in a solvent to remove the sizing agent)

-Unmodified PA (polyamide)-
・ PA66 (manufactured by DuPont, 101L)
・ MXD6 (manufactured by Mitsubishi Gas Chemical Company, S6007)

-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 a higher flexural modulus can be obtained as compared with the comparative example.
Further, in this example, it can be seen that a resin molded product having excellent impact resistance can be obtained as compared with the comparative example.

When the molded products produced in Examples 10 and 20 were analyzed by the method described above, a layer of the compatibilizer used (a layer of maleic anhydride-modified polypropylene) was interposed between the coating layer and the thermoplastic resin. It was confirmed that this was done (a layer of compatibilizer was formed on the surface of the coating layer).

Claims (26)

With thermoplastic resin
With carbon fiber
A terminal sterol-modified resin containing at least one of an amide bond and an imide bond in the main chain and having at least one end of the main chain modified with a sterol residue.
Only including,
A resin composition in which the thermoplastic resin is polyolefin. The resin composition according to claim 1, which comprises a compatibilizer. With thermoplastic resin
With carbon fiber
A terminal sterol-modified resin containing at least one of an amide bond and an imide bond in the main chain and having at least one end of the main chain modified with a sterol residue.
With a compatibilizer,
Resin composition containing. The resin composition according to claim 3, wherein the thermoplastic resin is polyolefin. The resin composition according to any one of claims 1 to 4, wherein the average fiber length of the carbon fibers is 0.1 mm or more and 5.0 mm or less. The resin composition according to any one of claims 1 to 5 , wherein the terminal sterol-modified resin is a polyamide having the amide bond in the main chain. The resin composition according to any one of claims 1 to 6 , 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 resin composition according to any one of claims 1 to 7 , wherein the content of the terminal sterol-modified resin 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. The resin composition according to any one of claims 1 to 8 , wherein the content of the terminal sterol-modified resin with respect to the mass of the carbon fibers is 0.1% by mass or more and 200% by mass or less. The resin composition according to any one of claims 2 to 4 , wherein the compatibilizer is a modified polyolefin. The resin composition according to any one of claims 2 to 4, 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 resin composition according to any one of claims 2 to 4 , wherein the content of the compatibilizer is 1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the terminal sterol-modified resin. The resin composition according to any one of claims 2 to 4 , wherein the content of the compatibilizer with respect to the mass of the carbon fibers is 1% by mass or more and 50% by mass or less. With thermoplastic resin
With carbon fiber
A terminal sterol-modified resin containing at least one of an amide bond and an imide bond in the main chain and having at least one end of the main chain modified with a sterol residue.
Only including,
A resin molded product in which the thermoplastic resin is polyolefin. The resin molded product according to claim 14, which contains a compatibilizer. With thermoplastic resin
With carbon fiber
A terminal sterol-modified resin containing at least one of an amide bond and an imide bond in the main chain and having at least one end of the main chain modified with a sterol residue.
With a compatibilizer,
Resin molded body containing. The resin molded product according to claim 16, wherein the thermoplastic resin is polyolefin. The resin molded product according to any one of claims 14 to 17, wherein the average fiber length of the carbon fibers is 0.1 mm or more and 5.0 mm or less. The resin molded product according to any one of claims 14 to 18 , wherein the terminal sterol-modified resin is a polyamide having the amide bond in the main chain. The resin molded product according to any one of claims 14 to 19 , 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 resin molded article according to any one of claims 14 to 20 , wherein the content of the terminal sterol-modified resin 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. The resin molded product according to any one of claims 14 to 21 , wherein the content of the terminal sterol-modified resin with respect to the mass of the carbon fibers is 0.1% by mass or more and 200% by mass or less. The resin molded product according to any one of claims 15 to 17 , wherein the compatibilizer is a modified polyolefin. The resin molded product according to any one of claims 15 to 17, 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 resin molded article according to any one of claims 15 to 17 , wherein the content of the compatibilizer is 1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the terminal sterol-modified resin. The resin molded product according to any one of claims 15 to 17 , wherein the content of the compatibilizer with respect to the mass of the carbon fibers is 1% by mass or more and 50% by mass or less.

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