JP6844449B2 - Resin composition and its molded product - Google Patents

Description

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to obtain a molded product having an excellent balance of rigidity and toughness, which is obtained by blending polyamide, polyrotaxane having a cyclic molecule modified by a graft chain, and a resin compatible with the resin constituting the graft chain. It relates to a polyamide resin composition and a molded article comprising the polyamide resin composition.

Polyamide has properties suitable for engineering plastics such as excellent mechanical properties such as rigidity and toughness and thermal properties. Therefore, mainly for injection molding, various electric / electronic parts, mechanical parts and automobiles. Widely used for parts and other applications. As a method for further improving the toughness of a polyamide resin, it is known to blend an olefin elastomer or a core-shell type compound in which a rubber-like core layer is covered with a glass-like resin shell layer. Examples of the technique for blending an olefin-based elastomer include a continuous phase made of a polyamide resin and a particulate dispersed phase made of a polyolefin modified with α, β-unsaturated carboxylic acid dispersed in the continuous phase. A polyamide-based resin composition (see, for example, Patent Document 1) has been proposed. As a technique for blending a core-shell type compound, for example, a multilayer structure having a polyalkyl (meth) acrylate as a core and a first layer made of polyorganosiloxane and a second layer made of polyalkyl (meth) acrylate on the core. A composite rubber-based graft copolymer obtained by graft-polymerizing a vinyl-based monomer to the coalesced particles, an impact-resistant thermoplastic resin composition composed of a thermoplastic resin (see, for example, Patent Document 2), and a terephthalic acid unit. Polyamide resin composition consisting of a dicarboxylic acid unit contained, a polyamide resin composed of 1,9-nonanediamine units and / or diamine units containing 2-methyl-1,8-octanediamine units, and resin fine particles having a core-shell structure. A thing (see, for example, Patent Document 3) has been proposed. When these resin compositions are applied to various uses, particularly automobile structural materials, it is necessary to achieve both rigidity and rigidity. The resin compositions disclosed in Patent Documents 1 to 3 have a problem that the rigidity is lowered, although the impact resistance and the toughness are improved by blending the olefin elastomer and the core-shell type compound.

On the other hand, as a method for improving impact strength and toughness, for example, a resin composition obtained by reacting a polyolefin modified with an unsaturated carboxylic acid anhydride with a polyrotaxane having a functional group (see, for example, Patent Document 4). , A polylactic acid-based resin composition containing a polyrotaxane in which an opening of a cyclic molecule having a graft chain made of polylactic acid is encapsulated by a linear molecule and a polylactic acid resin (see, for example, Patent Document 5) has been proposed. ing.

Japanese Unexamined Patent Publication No. 9-31325 Japanese Unexamined Patent Publication No. 5-339462 Japanese Unexamined Patent Publication No. 2000-186204 Japanese Unexamined Patent Publication No. 2013-209460 Japanese Unexamined Patent Publication No. 2014-84414

As disclosed in Patent Documents 4 to 5, it has been known that the impact strength and toughness of polyolefins and polylactic acids are improved by using polyrotaxane, but the resin composition described in Patent Document 4 has rigidity. There was a problem that was insufficient. Further, in the resin composition described in Patent Document 5, although the toughness of polylactic acid is improved, it is still insufficient. The polyrotaxanes disclosed in these references have low compatibility and reactivity with polyamides, and it has been difficult to apply such polyrotaxanes to the modification of polyamides.

In view of the above problems, an object of the present invention is to provide a polyamide resin composition capable of obtaining a molded product having an excellent balance of rigidity and toughness.

In order to solve the above problems, the present invention has the following configurations.
(1) A resin composition comprising at least a polyamide (A), a polyrotaxane (B) in which a cyclic molecule is modified by a graft chain, and a resin (C) compatible with the resin constituting the graft chain. 70 parts by weight or more and 99.8 parts by weight or less of the polyamide (A) with respect to a total of 100 parts by weight of the polyamide (A), the polyrotaxane (B) and the resin (C). A resin composition comprising 0.1 parts by weight or more and 15 parts by weight or less, and 0.1 part by weight or more and 15 parts by weight or less of the resin (C).
(2) The resin composition according to (1), wherein the graft chain is polyester.
(3) The resin composition according to (2), wherein the graft chain is polycaprolactone.
(4) The resin composition according to any one of (1) to (3), wherein the resin (C) has at least one hydroxyl group or a halogen group in the repeating unit.
(5) Described in any one of (1) to (4), wherein the resin (C) is at least one selected from the group consisting of a phenoxy resin, polyvinyl chloride, chlorinated polyethylene, and polyvinylphenol. Resin composition.
(6) The resin composition according to any one of (1) to (4), wherein the resin (C) is a phenoxy resin containing 50% by weight or more of a bisphenol F type phenoxy resin.
(7) The resin according to any one of (1) to (6), which has a sea phase containing the polyamide (A) as a main component and an island phase containing the polyrotaxane (B) and the resin (C) as main components. Composition.
(8) The resin composition according to (7), wherein the island phase has an average diameter of 1 μm or less.
(9) A molded product comprising the resin composition according to any one of (1) to (8).
(10) At least the polyamide (A), the polyrotaxane (B) in which the cyclic molecule is modified by the graft chain, and the resin (C) compatible with the resin constituting the graft chain are subjected to the polyamide (A) and the polyrotaxane (the polyrotaxane). 70 parts by weight or more and 99.8 parts by weight or less of the polyamide (A) and 0.1 parts by weight or more and 15 parts by weight of the polyrotaxane (B) with respect to 100 parts by weight of the total of B) and the resin (C). Hereinafter, a method for producing a resin composition, wherein the resin (C) is blended in an amount of 0.1 part by weight or more and 15 parts by weight or less.

With the polyamide resin composition of the present invention, a molded product having an excellent balance of rigidity and toughness can be obtained.

Hereinafter, the present invention will be described in more detail.

The resin composition of the present invention comprises at least a polyamide (A), a polyrotaxane (B) in which cyclic molecules are modified by a graft chain, and a resin (C) compatible with the resin constituting the graft chain. By blending the polyamide (A), the rigidity and heat resistance can be improved. Further, the toughness can be improved by blending polyrotaxane (B). Further, by blending the polyrotaxane (B) in which the cyclic molecule is modified by the graft chain and the resin (C) compatible with the resin constituting the graft chain, the polyamide (A), the polyrotaxane (B) and the resin ( The miscibility of C) is improved, and the toughness can be improved while maintaining the rigidity.

The polyamide (A) in the resin composition of the present invention contains amino acid, lactam or diamine and dicarboxylic acid residues as main constituents. Typical examples of the raw materials are amino acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and paraaminomethylbenzoic acid, lactam such as ε-caprolactam and ω-laurolactam, tetramethylenediamine and penta. Methylenediamine, hexamethylenediamine, 2-methylpentamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4-trimethylhexamethylenediamine, 5 − An aliphatic diamine such as methylnonamethylenediamine, an aromatic diamine such as metaxylylene diamine and paraxylylene diamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1- Amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane , Bis (aminopropyl) piperazine, alicyclic diamines such as aminoethyl piperazine, aliphatic dicarboxylic acids such as adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid Aromatic dicarboxylic acids such as acids, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodiumsulfoisophthalic acid, 2,6-naphthalenedicarboxylic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, 1,4-cyclohexane Examples thereof include alicyclic dicarboxylic acids such as dicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid and 1,3-cyclopentanedicarboxylic acid. In the present invention, two or more kinds of polyamide homopolymers or copolymers derived from these raw materials may be blended.

Specific examples of the polyamide (A) include polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polytetramethylene adipamide (nylon 46), and polytetramethylene sebacamide (nylon). 410), Polypentamethylene adipamide (Nylon 56), Polypentamethylene sebacamide (Nylon 510), Polyhexamethylene sebacamide (Nylon 610), Polyhexamethylene dodecamide (Nylon 612), Polydecamethylene Aji Pamide (Nylon 106), Polydecamethylene sebacamide (Nylon 1010), Polydecamethylene dodecamide (Nylon 1012), Polyundecaneamide (Nylon 11), Polydodecaneamide (Nylon 12), Polycaproamide / Polyhexa Methylene adipamide copolymer (nylon 6/66), polycaproamide / polyhexamethylene terephthalamide copolymer (nylon 6 / 6T), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (nylon 66 / 6T), poly Hexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polyhexamethylene terephthalamide / polydodecaneamide copolymer (nylon) 6T / 12), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyxylylene adipamide (nylon XD6), polyxylylene sebacamide (Nylon XD10), Polyhexamethylene terephthalamide / Polypentamethylene terephthalamide copolymer (Nylon 6T / 5T), Polyhexamethylene terephthalamide / Poly-2-methylpentamethylene terephthalamide copolymer (Nylon 6T / M5T), Polypentamethylene Telephthalamide / polydecamethylene terephthalamide copolymer (nylon 5T / 10T), polynonamethylene terephthalamide (nylon 9T), polydecamethylene terephthalamide (nylon 10T), polydodecamethylene terephthalamide (nylon 12T) and their co-weights Coalescence etc. can be mentioned. Two or more of these may be blended. Here, "/" indicates a copolymer, and the same applies hereinafter.

In the resin composition of the present invention, the melting point of the polyamide (A) is preferably 150 ° C. or higher and lower than 300 ° C. When the melting point is 150 ° C. or higher, the heat resistance can be improved. On the other hand, when the melting point is less than 300 ° C., the processing temperature at the time of producing the resin composition can be appropriately suppressed, and the thermal decomposition of polyrotaxane (B) can be suppressed.

Here, the melting point of the polyamide in the present invention is 20 ° C./min after lowering the temperature of the polyamide from the molten state to 30 ° C. at a temperature-lowering rate of 20 ° C./min under an inert gas atmosphere using a differential scanning calorimeter. It is defined as the temperature of the endothermic peak that appears when the temperature is raised to the melting point + 40 ° C. at the heating rate of. However, when two or more endothermic peaks are detected, the temperature of the endothermic peak having the highest peak intensity is set as the melting point.

Specific examples of polyamide having a melting point of 150 ° C. or higher and lower than 300 ° C. are polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polypentamethylene adipamide (nylon 56), and poly. Tetramethylene adipamide (nylon 46), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polyundecaneamide (nylon 11), polydodecaneamide (nylon 12), polycaproamide / Polyhexamethylene adipamide copolymer (nylon 6/66), polycaproamide / polyhexamethylene terephthalamide copolymer (nylon 6 / 6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I) ), Polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polyhexamethylene terephthalamide / polydodecaneamide copolymer (nylon 6T / 12), polyhexamethylene adipamide / polyhexamethylene terephthalamide / Polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyxylylene adipamide (nylon XD6), polyhexamethylene terephthalamide / poly-2-methylpentamethylene terephthalamide copolymer (nylon 6T / M5T), Examples thereof include polynonamethylene terephthalamide (nylon 9T) and copolymers thereof. Two or more of these may be blended.

The blending amount of the polyamide (A) in the resin composition of the present invention is 70 parts by weight or more and 99.8 parts by weight or less with respect to a total of 100 parts by weight of the polyamide (A), the polyrotaxane (B) and the resin (C). is there. When the blending amount of the polyamide (A) is less than 70 parts by weight, the rigidity and heat resistance of the obtained molded product are lowered. The blending amount of the polyamide (A) is preferably 90 parts by weight or more, more preferably 93 parts by weight or more. On the other hand, when the blending amount of the polyamide (A) exceeds 99.8 parts by weight, the blending amounts of the polyrotaxane (B) and the resin (C) are relatively small, so that the toughness of the molded product is lowered. The blending amount of the polyamide (A) is preferably 99.5 parts by weight or less.

The resin composition of the present invention comprises a polyrotaxane (B) in which a cyclic molecule is modified by a graft chain. Rotaxane is generally a dumbbell-shaped shaft molecule (having bulky blocking groups at both ends, as described in Harada, A., Li, J. & Kamachi, M., Nature 356, 325-327, for example. A straight-chain molecule; hereinafter referred to as a “linear molecule”) is a molecule in which a cyclic molecule is penetrated, and a molecule in which a plurality of cyclic molecules are penetrated through one linear molecule is called a polyrotaxane. ..

Polyrotaxane is composed of a linear molecule and a plurality of cyclic molecules, has a structure in which the linear molecule penetrates through the openings of the plurality of cyclic molecules, and has a cyclic molecule at both ends of the linear molecule. It has a bulky block group so as not to be detached from. In polyrotaxane, the cyclic molecule can move freely on the linear molecule, but has a structure that cannot escape from the linear molecule due to the blocking group. That is, the linear molecule and the cyclic molecule have a structure that maintains the morphology by a mechanical bond rather than a chemical bond. Since such polyrotaxane has high motility of cyclic molecules, it has an effect of relieving stress from the outside and stress remaining inside. Further, by blending polyrotaxane in which a cyclic molecule is modified by a graft chain into the polyamide, it is possible to spread the same effect on the polyamide.

The linear molecule is not particularly limited as long as it is a molecule having a functional group that penetrates the opening of the cyclic molecule and can react with the blocking group. Preferred linear molecules include polyalkylene glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol; polybutadiene diols, polyisoprene diols, polyisobutylene diols, poly (acrylonitrile-butadiene) diols, hydride polybutadiene diols, etc. Terminal hydroxyl diolates such as polyethylene diols and polypropylene diols; polyesters such as polycaprolactone diols, polylactic acid, polyethylene adipates, polybutylene adipates, polyethylene terephthalates and polybutylene terephthalates; terminal functional polysiloxanes such as terminal silanol-type polydimethylsiloxanes. Kind: Terminal amino group chain polymers such as terminal amino group polyethylene glycol, terminal amino group polypropylene glycol, terminal amino group polybutadiene; Trifunctional or higher polyfunctional chain having three or more of the above functional groups in one molecule. Examples include polymers. Of these, polyethylene glycol and / or terminal amino group polyethylene glycol are preferably used because polyrotaxane can be easily synthesized.

The number average molecular weight of the linear molecule is preferably 2,000 or more, and the rigidity can be further improved. 10,000 or more is more preferable. On the other hand, it is preferably 100,000 or less, the compatibility with the polyamide (A) can be improved, and the phase separation structure can be miniaturized, so that the toughness can be further improved. More preferably, it is 50,000 or less. Here, the number average molecular weight of the linear molecule is measured by gel permeation chromatography using hexafluoroisopropanol as a solvent and Shodex HFIP-806M (2) + HFIP-LG as a column. Refers to the converted value.

The blocking group is capable of binding to the terminal functional group of the linear molecule, and is not particularly limited as long as it is a group sufficiently bulky so that the cyclic molecule does not desorb from the linear molecule. Preferred examples of the blocking group include a dinitrophenyl group, a cyclodextrin group, an adamantyl group, a trityl group, a fluoresenyl group, a pyrenyl group, an anthracenyl group, a main chain of a polymer having a number average molecular weight of 1,000 to 1,000,000, or a main chain of a polymer. Side chains and the like can be mentioned. You may have two or more of these.

The cyclic molecule is not particularly limited as long as the linear molecule can penetrate through the opening. Preferred cyclic molecules include cyclodextrins, crown ethers, cryptands, macrocyclic amines, calixarenes, cyclophanes and the like. Cyclodextrins are compounds in which a plurality of glucoses are cyclically linked by α-1,4-bonds. α-Cyclodextrin, β-cyclodextrin, and γ-cyclodextrin are more preferably used.

The polyrotaxane (B) in the present invention is characterized in that a cyclic molecule is modified by a graft chain. By modifying the cyclic molecules with the graft chain, not only the miscibility with the polyamide (A) is improved, but also the cyclic molecules are prevented from aggregating due to hydrogen bonds and the motility of the cyclic molecules is hindered. Can be done.

The graft chain is preferably made of polyester. Aliphatic polyesters are more preferable from the viewpoint of compatibility with polyamide (A) and solubility in organic solvents. Aliphatic polyesters include polylactic acid, polyglycolic acid, poly3-hydroxybutyrate, poly4-hydroxybutyrate, poly (3-hydroxybutyrate / 3-hydroxyvalerate), poly (ε-caprolactone), and the like. Can be mentioned. Of these, poly (ε-caprolactone) is more preferable from the viewpoint of compatibility with polyamide (A). Here, the ratio of the graft chains in the polyrotaxane (B) is preferably 10 parts by weight or more. By setting the ratio of the graft chains to 10 parts by weight or more, it is possible to improve the compatibility between polyrotaxane (B) and other resins. The ratio of the graft chains is more preferably 30 parts by weight or more, and further preferably 50 parts by weight or more. The upper limit of the ratio of graft chains is preferably 80% or less. When it is set to 80% or less, the stress relaxation effect of polyrotaxane (B) can be sufficiently exerted.

The terminal group of the graft chain preferably has at least one functional group selected from the group consisting of a hydroxyl group, a carboxyl group, an isocyanate group, a glycidyl group and an amino group at the terminal. The carboxyl group and the glycidyl group have high reactivity with the amine terminal of the polyamide (A), and the isocyanate group and the amino group have high reactivity with the carboxyl terminal of the polyamide (A). Therefore, by modifying the cyclic molecule with the graft chain having the specific functional group, the compatibility of polyrotaxane (B) with the polyamide (A) is improved. As a result, the toughness can be improved while maintaining the rigidity of the polyamide (A), and the rigidity and toughness can be improved in a well-balanced manner.

The functional group at the end of the graft chain can be imparted, for example, by reacting polyrotaxane having a cyclic molecule modified by the graft chain with an introduction compound having a desired functional group and capable of reacting with the end of the graft chain. In this case, the functional group concentration at the terminal of the graft chain can be adjusted to a desired range by, for example, adjusting the charging ratio of the polyrotaxane in which the cyclic molecule is modified by the graft chain and the introduced compound.

The weight average molecular weight of polyrotaxane (B) in the resin composition of the present invention is preferably 100,000 or more, and the rigidity and toughness can be further improved. On the other hand, it is preferably 1 million or less, the compatibility with the polyamide (A) is improved, and the toughness can be further improved. Here, the weight average molecular weight of the linear molecule is measured by gel permeation chromatography using hexafluoroisopropanol as a solvent and Shodex HFIP-806M (2 bottles) + HFIP-LG as a column. Refers to the converted value.

The blending amount of polyrotaxane (B) in the resin composition of the present invention is 0.1 part by weight or more and 15 parts by weight or less with respect to 100 parts by weight of the total of polyamide (A), polyrotaxane (B) and resin (C). is there. If the blending amount of polyrotaxane (B) is less than 0.1 parts by weight, the stress relaxation effect of polyrotaxane (B) is not sufficiently exerted, and the toughness of the molded product is lowered. The blending amount of polyrotaxane (B) is preferably 0.5 parts by weight or more. On the other hand, when the blending amount of polyrotaxane (B) exceeds 15 parts by weight, the blending amount of polyamide (A) is relatively small, so that the rigidity and heat resistance of the obtained molded product are lowered. It is preferably 10 parts by weight or less, and more preferably 7 parts by weight or less.

The resin composition of the present invention comprises a resin (C) compatible with the resin constituting the graft chain of the polyrotaxane (B). Here, "compatible" means the resin and the component (C) constituting the graft chain of the component (B) in the composition included in the range of the compounding ratio of the component (B) and the component (C) of the present invention. In the ratio of, the resin and the component (C) constituting the graft chain of the component (B) are melted together with the resin and the component (C) constituting the graft chain of the component (B), which are above the melting point and below the decomposition point. It refers to a state in which no agglomerates or agglomerates can be confirmed when the mixture is mixed in the above temperature range and observed at a magnification of 100 times using an optical microscope. In the present invention, the resin constituting the graft chain of polyrotaxane (B) and the resin (C) are compatible with each other to improve the miscibility of the polyamide (A), the polyrotaxane (B) and the resin (C), and to provide rigidity. The toughness can be improved while maintaining the above.

It is preferable that the repeating unit of the resin (C) has at least one hydroxyl group or a halogen group. By having a hydroxyl group or a halogen group in the repeating unit, the polarity of the resin (C) is increased, and the miscibility of the polyamide (A), the polyrotaxane (B) and the resin (C) is further improved.

Examples of the halogen group include a chloro group, a fluoro group, a bromo group and an iodine group.

Specific examples of the resin (C) include phenoxy resin, polyvinyl chloride, chlorinated polyethylene, and polyvinylphenol. These are not limited to one type, but may be added in combination of a plurality of types. Of these, a phenoxy resin is preferably used from the viewpoint of processability and heat resistance.

The type of phenoxy resin is not particularly limited, but bisphenol A type phenoxy resin, bisphenol F type phenoxy resin, or a mixture thereof is preferably used because it is excellent in processability and handleability. Among them, since the miscibility of the polyamide (A), the polyrotaxane (B) and the resin (C) is further improved, the phenoxy resin containing 50% by weight or more of the bisphenol F type phenoxy resin is preferable, and 75% by weight or more is contained. Is more preferable, and 90% by weight or more is further preferable.

The resin composition of the present invention preferably has a sea phase containing polyamide (A) as a main component and an island phase containing polyrotaxane (B) and a resin (C) as main components. In addition, it has a sea phase containing polyamide (A) as a main component, an island phase containing polyrotaxane (B) and a resin (C) as main components, and a lake containing polyamide (A) as a main component in the island phase. It may have a so-called sea island lake structure having a phase. Here, the "main component" refers to a component that occupies 80% by weight or more in the phase. Since polyrotaxane (B) and resin (C) are compatible with each other, it can be said that they both exist in the same island phase. The "island phase containing the component (B) and the component (C) as the main components" means that the total amount of the polyrotaxane (B) and the resin (C) in the island phase accounts for 80% by weight or more. It is known that the properties of the resin composition are also affected by the phase-separated structure and its phase size. A resin composition composed of two or more kinds of components and having a phase-separated structure exhibits excellent properties as compared with the case of each component alone by drawing out the advantages of each component and compensating for the disadvantages. By having such a sea-island structure or a sea-island lake structure, the resin composition of the present invention can suppress crack growth at the time of fracture and further improve toughness. That is, the cracks formed by stress concentration propagate through the sea phase containing polyamide (A) as a main component, but cracks are caused by the presence of island phases containing polyrotaxane (B) and resin (C) as main components. Is guided to a relatively flexible island phase, where stress is dispersed and crack propagation is suppressed.

In the sea-island structure, the average diameter of the island phases is preferably 0.01 μm or more, more preferably 0.05 μm or more. When the average diameter of the island phase is 0.01 μm or more, the characteristics derived from the phase-separated structure can be exhibited more effectively, and the toughness can be further improved. The average diameter of the island phase is preferably 1 μm or less, more preferably 0.5 μm or less. When the average diameter of the island phase is 1 μm or less, the effect of suppressing crack growth at the time of fracture is more effectively exhibited, and the toughness can be further improved. Further, the rigidity can be further improved by reducing the phase of the flexible polyrotaxane (B) and the resin (C). When forming a sea-island lake structure, the average diameter of the lake fauna is not particularly limited, but is preferably 0.005 μm or more, and is preferably 1/2 or less of the average diameter of the island fauna.

The average diameter of the island phase of the sea-island structure or the island phase and the lake phase of the sea-island lake structure in the resin composition of the present invention can be determined by the following method by electron microscope observation. Since the phase-separated structure of the resin composition and the size of each phase do not change under general molding conditions, in the present invention, the phase-separated structure is observed using a test piece obtained by molding the resin composition. To do. First, the central part of the JIS-1 strip-shaped test piece (length 80 mm x width 10 mm x thickness 4 mm) obtained by injection molding is cut into a 1 to 2 mm square, and a polyamide (A) is used with phosphotungstic acid / osmium. ) Is stained, and then an ultrathin section of 0.1 μm or less (about 80 nm) is cut with an ultramicrotome at -196 ° C. to obtain a sample for a transmission electron microscope. When determining the average diameter of the island phases of the sea-island structure, the magnification of the above-mentioned transmission electron microscope sample is adjusted so that 50 or more and less than 100 island phases are present in the square electron microscope observation photograph. At such a magnification, 50 island phases are randomly selected from the island phases existing in the observation image, and the major axis and the minor axis are measured for each island phase. The average value of the major axis and the minor axis is defined as the diameter of each island phase, and the average value of the diameters of all the measured island phases is defined as the diameter of the island phase. The major axis and the minor axis of the island phase or the lake phase indicate the longest diameter and the shortest diameter of the island phase, respectively.

The sea-island structure in which the average diameter of the island phase is in the above-mentioned preferable range can be obtained, for example, by setting the blending amounts of the polyamide (A) and the polyrotaxane (B) in the above-mentioned preferable range. The smaller the amount of polyrotaxane (B), the smaller the average diameter of the island phase, and the larger the amount of polyrotaxane (B), the larger the average diameter of the island phase.

The resin composition of the present invention may further contain a filler, a thermoplastic resin other than the polyamide (A) and the resin (C), various additives and the like, as long as the object of the present invention is not impaired.

By blending the filler, the strength and rigidity of the obtained molded product can be further improved. The filler may be either an organic filler or an inorganic filler, or may be a fibrous filler or a non-fibrous filler. Two or more of these may be blended.

Examples of the fibrous filler include glass fiber and carbon fiber. These may be coated or focused with a thermoplastic resin such as ethylene / vinyl acetate or a thermosetting resin such as an epoxy resin. Examples of the cross-sectional shape of the fibrous filler include a circular shape, a flat shape, an eyebrows shape, an oval shape, an elliptical shape, and a rectangular shape.

Examples of the non-fibrous filler include non-swelling silicates such as talc, wallastenite, zeolite, sericite, mica, kaolin, clay, pyrophyllite, bentonite, asbestos, alumina silicate, and calcium silicate, and Li-type fluorine. Swellable layered silicates such as teniolite, Na-type fluorine teniolite, Na-type tetrasilicon fluorine mica, and swellable mica of Li-type tetrasilicon fluorine mica, silicon oxide, magnesium oxide, alumina, silica, diatomaceous soil, zirconium oxide, titanium oxide, Metal oxides such as iron oxide, zinc oxide, calcium oxide, tin oxide, antimony oxide, metal carbonates such as calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dolomite, hydrotalcite, calcium sulfate, barium sulfate, etc. Metal hydroxides such as metal sulfate, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, basic magnesium carbonate, smectite clay minerals such as montmorillonite, biderite, nontronite, saponite, hectolite, and soconite, and vermiculite, Various clay minerals such as halloysite, kanemite, keniyaite, zirconium phosphate, titanium phosphate, glass beads, glass flakes, ceramic beads, boron nitride, aluminum nitride, silicon carbide, calcium phosphate, carbon black, graphite and the like can be mentioned. In the above-mentioned swellable layered silicate, exchangeable cations existing between layers may be exchanged with organic onium ions. Examples of the organic onium ion include ammonium ion, phosphonium ion, sulfonium ion and the like.

Specific examples of resins other than polyamide (A) and resin (C) include polyolefin resins, modified polyphenylene ether resins, polysulfone resins, polyketone resins, polyetherimide resins, polyarylate resins, polyether sulfone resins, and polyether ketones. Examples thereof include resins, polythioether ketone resins, polyether ether ketone resins, polyimide resins, polyamideimide resins, and tetrafluoride polyethylene resins. Two or more of these may be blended. The content of other components is preferably less than 100 parts by weight, more preferably less than 50 important parts, and even more preferably less than 30 parts by weight with respect to 100 parts by weight of the polyamide (A).

Specific examples of various additives include heat stabilizers other than copper compounds, isocyanate compounds, organic silane compounds, organic titanate compounds, organic borane compounds, coupling agents such as epoxy compounds, and polyalkylene oxide oligomer compounds. , Plastic agents such as thioether compounds, ester compounds, organic phosphorus compounds, crystal nucleating agents such as organic phosphorus compounds, polyether ether ketones, waxes montanate, metal soaps such as lithium montanate, aluminum stearate, ethylenediamine -Stearic acid / sebacic acid polycondensate, mold release agent such as silicone compound, color inhibitor such as hypophosphate, lubricant, ultraviolet inhibitor, colorant, flame retardant, foaming agent, etc. can be mentioned. .. When these additives are blended, the blending amount thereof is preferably 10 parts by weight or less, more preferably 1 part by weight or less, based on 100 parts by weight of the polyamide (A) in order to fully utilize the characteristics of the polyamide.

Examples of heat stabilizers other than copper compounds include N, N'-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamide) and tetrakis [methylene-3- (3', 5'-di). -T-butyl-4'-hydroxyphenyl) propionate] Phenolic compounds such as methane, phosphorus compounds, mercaptobenzoimidazole compounds, dithiocarbamic acid compounds, sulfur compounds such as organic thioic acid compounds, N, N' Examples thereof include amine compounds such as −di-2-naphthyl-p-phenylenediamine and 4,4′-bis (α, α-dimethylbenzyl) diphenylamine. Two or more of these may be blended.

The method for producing the polyamide resin composition of the present invention is not particularly limited, and examples thereof include a method of kneading in a molten state and a method of mixing in a solution state. From the viewpoint of improving reactivity, a method of kneading in a molten state is preferable. Examples of the melt-kneading device for kneading in a molten state include a multi-screw extruder such as a single-screw extruder, a twin-screw extruder, and a four-screw extruder, an extruder such as a twin-screw single-screw compound extruder, and a kneader. Can be mentioned. From the viewpoint of productivity, an extruder capable of continuously producing is preferable, and from the viewpoint of improving kneadability, reactivity and productivity, a twin-screw extruder is more preferable.

Hereinafter, a case where the resin composition of the present invention is produced using a twin-screw extruder will be described as an example. The maximum resin temperature is preferably 300 ° C. or lower from the viewpoint of suppressing thermal deterioration of polyrotaxane (B) and further improving toughness. On the other hand, the maximum resin temperature is preferably equal to or higher than the melting point of the polyamide (A). Here, the maximum resin temperature refers to the highest temperature measured by resin thermometers evenly installed at a plurality of locations of the extruder.

The extrusion amount of the resin composition is preferably 0.01 kg / h or more per 1 rpm of screw rotation, preferably 0.05 kg, from the viewpoint of further suppressing thermal deterioration of the polyamide (A), polyrotaxane (B) and resin (C). / H or more is more preferable. On the other hand, from the viewpoint of further promoting the reaction between the polyamide (A) and the polyrotaxane (B) resin and more easily forming the above-mentioned sea-island structure, 1 kg / h or less per 1 rpm of screw rotation is preferable. Here, the extrusion amount refers to the weight (kg) of the resin composition discharged from the extruder per hour.

In this way, the resin composition can be molded by a generally known method, and various molded products such as sheets and films can be obtained. Examples of the molding method include injection molding, injection compression molding, extrusion molding, compression molding, blow molding, press molding and the like.

The resin composition of the present invention and its molded product can be used for various purposes such as automobile parts, electric / electronic parts, building materials, various containers, daily necessities, household goods and sanitary goods by utilizing its excellent properties. In particular, it is particularly preferably used for automobile exterior parts that require toughness and rigidity, automobile electrical components, automobile underhood parts, automobile gear parts, housings, connectors, reflectors, and other electric and electronic parts. Specifically, automobile engine peripheral parts such as engine cover, air intake pipe, timing belt cover, intake manifold, filler cap, throttle body, cooling fan, cooling fan, radiator tank top and base, cylinder head cover, oil pan, etc. Automotive underhood parts such as brake pipes, fuel piping tubes, waste gas system parts, automobile gear parts such as gears, actuators, bearing retainers, bearing cages, chain guides, chain tensioners, shift lever brackets, steering lock brackets, key cylinders. , Door inner handle, door handle cowl, interior mirror bracket, air conditioner switch, instrument panel, console box, glove box, steering wheel, trim and other automobile interior parts, front fender, rear fender, fuel lid, door panel, cylinder head cover, door mirror Stays, tailgate panels, licensed garnishes, roof rails, engine mount brackets, rear garnishes, rear spoilers, trunk lids, rocker moldings, moldings, lamp housings, front grilles, mudguards, side bumpers and other automotive exterior parts, air intake manifolds, intercoolers Inlet, exhaust pipe cover, inner bush, bearing retainer, engine mount, engine head cover, resonator, and intake / exhaust system parts such as throttle body, chain cover, thermostat housing, outlet pipe, radiator tank, oil nator, and delivery pipe. Engine cooling water system parts, connectors and wire harness connectors, motor parts, lamp sockets, sensor in-vehicle switches, automobile electrical parts such as combination switches, SMT compatible connectors, sockets, card connectors, jacks, power supply parts, switches, sensors, condenser seats Electrical and electronic components such as plates, relays, resistors, fuse holders, coil bobbins, IC and LED compatible housings, and reflectors can be preferably mentioned.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples. The following raw materials were used to obtain the resin compositions of each example.

<Polyamide>
(A-1): Nylon 6 resin (“Amilan” (registered trademark) manufactured by Toray Industries, Inc., η _r = 2.70, melting point 225 ° C., amide group concentration 10.5 mmol / g).
(A-2): Nylon 6 resin (produced by the method of Reference Example 1), η _r = 2.38, melting point 225 ° C., amide group concentration 10.2 mmol / g.

Here, the relative viscosity eta _r is 98% concentrated sulfuric acid 0.01 g / ml solution, was measured at 25 ° C.. The melting point is determined by lowering the temperature of the polyamide from the molten state to 30 ° C. at a temperature lowering rate of 20 ° C./min in an inert gas atmosphere using a differential scanning calorimeter, and then melting point +40 at a heating rate of 20 ° C./min. The temperature of the endothermic peak that appears when the temperature is raised to ° C. However, when two or more endothermic peaks are detected, the temperature of the endothermic peak having the highest peak intensity is taken as the melting point. The amide group concentration was calculated by the following formula (1) from the structural formula of the structural unit.
Amide group concentration (mol / g) = (number of amide groups in structural unit / molecular weight in structural unit) (1).

<Polyrotaxan>
(B-1): Polyrotaxane (“SELM” (registered trademark) Superpolymer SH2400P manufactured by Advanced Soft Materials Co., Ltd.). Polyethylene glycol, which is a linear molecule, has a number average molecular weight of 20,000 and an overall weight average molecular weight of 400,000.
(B-2): Polyrotaxane (“SELM” (registered trademark) Superpolymer SH3400P manufactured by Advanced Soft Materials Co., Ltd.). Polyethylene glycol, which is a linear molecule, has a number average molecular weight of 35,000 and an overall weight average molecular weight of 700,000.
(B-3): Polyrotaxane (“SELM” (registered trademark) Superpolymer SH2400P manufactured by Advanced Soft Material Co., Ltd.) was prepared by modifying the graft chain end with succinic anhydride by the method described in Reference Example 2. Polyethylene glycol, which is a linear molecule, has a number average molecular weight of 20,000 and an overall weight average molecular weight of 400,000.
(B'-4): Polyrotaxane was prepared by the method described in Reference Example 3.

Here, the weight average molecular weight of polyrotaxane is a value in terms of polymethylmethacrylate, which was measured by gel permeation chromatography using hexafluoroisopropanol as a solvent and Shodex HFIP-806M (2 bottles) + HFIP-LG as a column. Is.

All of the "SELM®" superpolymers used as raw materials in (B-1) to (B-3) are α-cyclodextrins in which the cyclic molecule is modified with a graft chain composed of poly (ε-caprolactone). , The straight-chain molecule is polyethylene glycol, and the blocking group is polyrotaxane, which is an adamantane group.

<Resin C>
(C-1): Phenoxy resin (manufactured by Mitsubishi Chemical Corporation, 1256). It is compatible with poly (ε-caprolactone). Bisphenol A type phenoxy resin.
(C-2): Polystyrene (PS Japan Corporation, HF77). Incompatible with poly (ε-caprolactone).
(C-3): Phenoxy resin (manufactured by Mitsubishi Chemical Corporation, 4250). It is compatible with poly (ε-caprolactone). A mixture of bisphenol A type phenoxy resin / bisphenol F type phenoxy resin = 50/50% by weight.
(C-4): Phenoxy resin (manufactured by Mitsubishi Chemical Corporation, 4275). It is compatible with poly (ε-caprolactone). A mixture of bisphenol A type phenoxy resin / bisphenol F type phenoxy resin = 25/75% by weight.

(Reference example 1)
700 g of ε-caprolactam and 18.2 g of a 30 wt% aqueous solution of hexamethylenediamine (0.80 mol% with respect to ε-caprolactam) were charged into a preheater, sealed, replaced with nitrogen, and preheated at 120 ° C. The preheated raw material was supplied to the polymerization can and heated at 285 ° C. After the heating was started and the pressure inside the can reached 0.6 MPa, the pressure inside the can was maintained at 0.6 MPa for 1.5 hours while releasing water to the outside of the system. After that, the pressure inside the can was returned to normal pressure over 30 minutes, and the can was further heated at a reduced pressure of 60 kPa and a heater temperature of 285 ° C. for 2 hours. Then, the polymer was discharged from the polymerization can in a gut shape and pelletized. The obtained pellets were extracted with hot water, vacuum dried at 80 ° C. for 24 hours, and then subjected to solid phase polymerization at 50 Pa and 200 ° C., nylon 6 (A-2) having _{η r = 2.38 and a melting point of 225 ° C.} Got

(Reference example 2)
50 g of "Serum" superpolymer SH2400P was dissolved in 500 ml of toluene solution, 0.8 g of succinic anhydride was added, and the mixture was heated at 90 ° C. for 6 hours under a nitrogen flow. After concentrating with an evaporator until the polymer concentration reached about 50%, the polymer solution was added to a large excess of methanol solution, and the precipitate was recovered. The obtained precipitate was dried in a vacuum dryer at 80 ° C. for 8 hours to obtain a polymer (B-3). When the obtained polymer was dissolved in benzyl alcohol and titrated with a potassium hydroxide solution having a known concentration, it was found that the ^{concentration of the carboxyl group at the terminal of the graft chain was 2.48 × 10 -4 mol / g.}

(Reference example 3)
1.0 g of α-cyclodextrin and 4.0 g of terminal amino group polyethylene glycol having a number average molecular weight of 20,000 were dissolved in distilled water at 80 ° C. to obtain an aqueous solution. The obtained aqueous solution was allowed to stand overnight in a refrigerator, and then water was removed from the obtained cloudy solution by freeze-drying to obtain a white solid. To the white solid, 0.7 ml of diisopropylethylamine, 0.85 g of adamantane acetic acid, 0.6 g of 1-hydroxybenzotriazole, 1.8 g of benzotriazole-1-yloxytris (dimethylamino) phosphonium hexafluorophosphate and 30 ml of dimethylformamide were added. In addition, the reaction was carried out at 5 ° C. for 24 hours under the inclusion of nitrogen. 20 ml of methanol was added to the obtained reaction solution, and centrifugation was performed. The obtained solid was further washed and centrifuged twice with a mixed solvent of methanol: dimethylformamide = 20 ml: 20 ml and twice with 60 ml of methanol, and then vacuum dried. The obtained solid was dissolved in 20 ml of dimethyl sulfoxide, added dropwise to 200 ml of water to cause a precipitate, and centrifuged to remove the supernatant. Further, after washing and centrifuging with 100 ml of water and 100 ml of methanol, respectively, the mixture was vacuum dried to obtain polyrotaxane (B'-4) having both ends sealed with an adamantane group. In this polyrotaxane, cyclodextrin, which is a cyclic molecule, is not modified by a graft chain.

<Evaluation method>
The evaluation method in each Example and Comparative Example will be described. Unless otherwise specified, the number of evaluation n was set to n = 5, and the average value was calculated.

(1) Morphology of phase-separated structure and average diameter of island phase The pellets obtained in each Example and Comparative Example were dried under reduced pressure at 80 ° C. for 12 hours, and were dried using an injection molding machine (SG75H-MIV manufactured by Sumitomo Heavy Industries, Ltd.). , Cylinder temperature: 240 ° C., mold temperature: 80 ° C., ASTM No. 4 dumbbell with a thickness of 3.2 mm was produced by injection molding. A part was cut out from this dumbbell test piece, and a sample for cross-section observation of about 2 mm × about 1 mm was prepared using a Leica ultramicrotome (EM UC7) with a diamond knife. The prepared sample is stained with phosphotungstic acid / osmium so as to have sufficient contrast in morphology, and then observed with a transmission electron microscope (H-7100 manufactured by Hitachi, Ltd.) at an acceleration voltage of 100 kV. The phase structure of the cross section of the sample was observed. The sea-island structure is a structure in which island phases containing the other component as the main component are scattered in the sea phase containing one component as the main component.

For each sample forming the sea-island structure, the average diameter of the island structure was determined by the following method. The magnification was adjusted so that there were 50 or more and less than 100 island structures in the square electron microscopic observation photograph. At such a magnification, 50 island structures were randomly selected from the island structures existing in the observation image, and the major axis and the minor axis were measured for each island structure. The average value of the major axis and the minor axis was taken as the diameter of each island structure, and the average value of the diameters of all the measured island structures was taken as the average diameter of the island structure.

(2) Toughness (tensile fracture elongation)
The pellets obtained in each Example and Comparative Example were dried under reduced pressure at 80 ° C. for 12 hours, and using an injection molding machine (SG75H-MIV manufactured by Sumitomo Heavy Industries, Ltd.), the cylinder temperature was 240 ° C. and the mold temperature was 80 ° C. By injection molding under the conditions, a multipurpose test piece A type obtained based on ISO3167 was produced. Tensile test pieces obtained from this multipurpose test piece were subjected to a tensile test at a crosshead speed of 100 mm / min using a tensile tester Tensilon UTA2.5T (manufactured by Orientec) in accordance with ISO527 (2012), and tensile fracture. Elongation was measured.

(3) Rigidity (flexural modulus)
The pellets obtained in each Example and Comparative Example were dried under reduced pressure at 80 ° C. for 12 hours, and using an injection molding machine (SG75H-MIV manufactured by Sumitomo Heavy Industries, Ltd.), the cylinder temperature was 240 ° C. and the mold temperature was 80 ° C. By injection molding under the conditions, a multipurpose test piece A type obtained based on ISO3167 was produced. The bending test piece obtained from this multipurpose test piece was subjected to a bending test at a crosshead speed of 2 mm / min using a bending tester Tensilon RTA-1T (manufactured by Orientec) in accordance with ISO178 (2001), and a flexural modulus. Asked.

(Examples 1 to 7, Comparative Examples 1 to 6)
Polyamide resin (A), polyrotaxane (B) and resin (C) are blended so as to have the composition shown in Table 1, preblended, and the cylinder temperature is set to 240 ° C. and the screw rotation speed is set to 200 rpm. It was supplied to an extruder (PCM-30 type made by Ikekai Steel) and melt-kneaded. The gut discharged from the extruder was pelletized to obtain pellets. Table 1 shows the results of evaluation by the above method using the obtained pellets.

From the comparison of Examples 1 to 9 and Comparative Examples 1 to 4, when the polyrotaxane in which the cyclic molecule was modified with the graft chain of poly (ε-caprolactone) and the phenoxy resin compatible with poly (ε-caprolactone) were blended. , It can be seen that the balance between toughness and rigidity is excellent as compared with the case where the phenoxy resin is not blended or the case where the phenoxy resin and polyrotaxane are not blended. On the other hand, from the comparison between Examples 4 and 5 and Comparative Example 5, it can be seen that the toughness is lowered when the polyrotaxane in which the cyclic molecule is not modified with the graft chain is blended. Further, from the comparison between Example 2 and Comparative Example 6, when polyrotaxane in which the cyclic molecule was modified with a graft chain of poly (ε-caprolactone) and a phenoxy resin compatible with poly (ε-caprolactone) were blended, phenoxy was added. It can be seen that the average diameter of the island phase is finer and the balance between toughness and rigidity is excellent as compared with the case where polystyrene that is incompatible with poly (ε-caprolactone) is blended instead of the resin. Further, from the comparison between Examples 3 and 8 and 9, by blending the phenoxy resin containing 50% by weight or more of the bisphenol F type phenoxy resin, the average diameter of the island phase can be further made finer and the performance can be improved. Understand.

Claims (10)

A resin composition comprising at least a polyamide (A), a polyrotaxane (B) in which a cyclic molecule is modified by a graft chain, and a resin (C) compatible with the resin constituting the graft chain. 70 parts by weight or more and 99.8 parts by weight or less of the polyamide (A) and 0.1 parts by weight of the polyrotaxane (B) with respect to a total of 100 parts by weight of (A), the polyrotaxane (B) and the resin (C). A resin composition comprising 0.1 parts by weight or more and 15 parts by weight or less of the resin (C) and 0.1 parts by weight or more and 15 parts by weight or less. The resin composition according to claim 1, wherein the graft chain is polyester. The resin composition according to claim 2, wherein the graft chain is polycaprolactone. The resin composition according to any one of claims 1 to 3, wherein the resin (C) has at least one hydroxyl group or a halogen group in the repeating unit. The resin composition according to any one of claims 1 to 4, wherein the resin (C) is at least one selected from the group consisting of a phenoxy resin, polyvinyl chloride, chlorinated polyethylene, and polyvinylphenol. The resin composition according to any one of claims 1 to 4, wherein the resin (C) is a phenoxy resin containing 50% by weight or more of a bisphenol F-type phenoxy resin. The resin composition according to any one of claims 1 to 6, which has a sea phase containing the polyamide (A) as a main component and an island phase containing the polyrotaxane (B) and the resin (C) as main components. The resin composition according to claim 7, wherein the island phase has an average diameter of 1 μm or less. A molded product comprising the resin composition according to any one of claims 1 to 8. At least the polyamide (A), the polyrotaxane (B) in which the cyclic molecule is modified by the graft chain, and the resin (C) compatible with the resin constituting the graft chain are subjected to the polyamide (A), the polyrotaxane (B), and the like. 70 parts by weight or more and 99.8 parts by weight or less of the polyamide (A) and 0.1 parts by weight or more and 15 parts by weight or less of the polyrotaxane (B) with respect to a total of 100 parts by weight of the resin (C). A method for producing a resin composition, which comprises 0.1 parts by weight or more and 15 parts by weight or less of the resin (C).