JP2006143772A - Resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a resin composition that has excellent rigidity, heat resistance and moldability, is useful as moldings substantially in various fields and reduces the use ratio of an exhaustible resource represented by petroleum. <P>SOLUTION: The resin composition is obtained by mixing 50-95% by mass of a polyamide resin composition (A) in which 0.1-20 parts by mass of a silicate layer of swellable phyllosilicate is dispersed in 100 parts by mass of a polyamide resin with 50-5% by mass of a biodegradable polyester resin (B) in a molten state. The biodegradable polyester resin (B) is preferably a polylactic acid. Preferably 100 parts by mass of the total of the polyamide resin composition (A) and the biodegradable polyester resin (B) are mixed with 0.05-5 parts by mass of an unsaturated carboxylic acid compound and/or an unsaturated epoxy compound (C). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention comprises a polyamide resin in which a silicate layer of a swellable layered silicate is dispersed and a biodegradable polyester resin, and is excellent in mechanical strength, heat resistance, moldability, and dependence on petroleum products. The present invention relates to a low resin composition.

  In general, polyamide resins are widely used as members of automobiles and electrical products by taking advantage of excellent strength and heat resistance. However, a molded body produced from a polyamide resin increases the amount of dust when discarded, and hardly decomposes in a natural environment, so that it remains semi-permanently even if it is buried. In addition, since it is a petroleum-based resin that uses petroleum as a starting material, the environmental impact during production is large.

  On the other hand, in recent years, biodegradable polyester resins such as polylactic acid have attracted attention from the viewpoint of environmental conservation (for example, see Patent Documents 1 and 2). Of the biodegradable resins, polylactic acid is one of the most heat-resistant resins, and can be mass-produced, so the cost is low and the utility is high. Furthermore, polylactic acid can be produced using plants such as corn and sweet potato as raw materials, and can contribute to saving depleted resources such as oil.

However, even polylactic acid with high heat resistance among biodegradable resins has a low crystallization rate, and therefore has poor moldability and poor heat resistance of the molded body, so that the molded body can withstand practical use as an automobile or an electrical member. Was not obtained.
JP-A-4-220456 JP-A-8-193165

  The present invention solves the above problems, is excellent in rigidity, heat resistance, moldability, can be used as a molded article in various fields, and uses depleted resources represented by petroleum. It is a technical problem to provide a resin composition having a reduced ratio.

  As a result of intensive research in order to solve the above problems, the present inventor mixed a polyamide resin composition in which a silicate layer of a swellable layered silicate is dispersed and a biodegradable polyester resin within a specific range. The present inventors have found that the obtained resin composition is excellent in mechanical strength, heat resistance, and handleability at the time of molding, and reached the present invention.

That is, the gist of the present invention is as follows.
(1) Polyamide resin composition (A) in which 0.1 to 20 parts by mass of a swellable layered silicate silicate layer is dispersed in 100 parts by mass of a polyamide resin, and biodegradable polyester resin (B) A resin composition obtained by melt-kneading 50 to 5% by mass.
(2) Unsaturated carboxylic acid compound and / or unsaturated epoxy compound (C) 0.05 to 5 parts by mass are added to a total of 100 parts by mass of the polyamide resin composition (A) and the biodegradable polyester resin (B). The resin composition as described in (1) above, wherein
(3) The resin composition as described in (1) or (2) above, wherein the biodegradable polyester resin (B) is polylactic acid.
(4) The biodegradable polyester resin (B) is characterized in that 0.1 to 20 parts by mass of a swellable layered silicate silicate layer is dispersed in 100 parts by mass of the biodegradable polyester resin (B). The resin composition according to any one of (1) to (3) above.

  ADVANTAGE OF THE INVENTION According to this invention, the resin composition which has the outstanding mechanical characteristic, heat resistance, and a moldability, and has low dependence on a petroleum-type product is provided. This resin composition can be a useful molded product that can be practically used in automobiles, electrical machinery, and other fields, and also uses biodegradable resins derived from natural products in part. It becomes possible to contribute to saving of depleted resources.

  Hereinafter, the present invention will be described in detail.

  The resin composition of the present invention is obtained by melt-kneading the polyamide resin composition (A) and the biodegradable polyester resin (B). First, the polyamide resin composition (A) will be described.

  The polyamide resin composition (A) in the present invention is a polyamide resin matrix in which a silicate layer of a swellable layered silicate is dispersed at a molecular level. Here, the silicate layer is a basic unit constituting the swellable layered silicate, and is a plate-like inorganic crystal obtained by breaking the layer structure of the swellable layered silicate (hereinafter referred to as “cleavage”). is there.

  The silicate layer in the present invention means that each silicate layer or a polyamide molecular chain is inserted between the layers, but the laminated structure is not completely broken, and is not necessarily one piece. It does not need to be peeled up to one sheet. In addition, when dispersed in the polyamide resin matrix, the swellable layered silicate silicate layer is dispersed at a molecular level, and each layer maintains an average interlayer distance of 1 nm or more and does not form a lump. The state that is. Here, the lump refers to a state where the raw swellable layered silicate is not cleaved at all. The interlayer distance is a distance between opposing silicate layers. Such a state can be confirmed by performing observation with a transmission electron microscope, for example, on the test piece of the polyamide composite material.

  The swellable layered silicate used in the present invention has a structure composed of a negatively charged crystal layer mainly composed of silicate and a cation having an ion exchange ability interposed between the layers. It is desirable that the cation exchange capacity determined by the method is 50 meq / 100 g or more. When the cation exchange capacity is less than 50 meq / 100 g, the swelling ability is low, so that the polyamide composite material remains substantially in an uncleavage state, and no performance improvement is observed. In the present invention, the upper limit of the cation exchange capacity value is not particularly limited, and an appropriate one may be selected from swellable layered silicates that can be actually prepared.

  Such swellable layered silicates may be naturally occurring or artificially synthesized or modified, for example, smectites (montmorillonite, beidellite, hectorite, soconite, etc.), vermiculites (vermiculite, etc.) , Mica (fluorine mica, muscovite, paragonite, phlogopite, lepidrite) In the present invention, Na-type or Li-type swellable fluorinated mica and montmorillonite are particularly preferably used.

  The swellable fluorine mica preferably used in the present invention generally has a structural formula represented by the following formula.

M _a (Mg _x Li _b ) Si ₄ O _y F _z
(In the formula, M represents an ion-exchangeable cation, and specific examples include sodium and lithium. A, b, X, Y, and Z represent coefficients, respectively, 0 ≦ a ≦ 0.5, 0 ≦ b ≦ 0.5, 2.5 ≦ X ≦ 3, 10 ≦ Y ≦ 11, 1.0 ≦ Z ≦ 2.0)
As a method for producing such swellable fluorine mica, for example, silicon oxide, magnesium oxide and various fluorides are mixed, and the mixture is completely melted in an electric furnace or a gas furnace at a temperature range of 1400 to 1500 ° C., An example is a melting method in which a swellable fluorine mica crystal is grown in the reaction vessel during the cooling process.

On the other hand, there is also a method of using talc [Mg ₃ Si ₄ O ₁₀ (OH) ₂ ] as a starting material and intercalating alkali metal ions to impart swellability to obtain a swellable fluoromica (Japanese Patent Laid-Open No. Hei. No. 2-149415). In this method, swellable fluoromica can be obtained by heat-treating talc and alkali silicofluoride mixed at a predetermined mixing ratio in a magnetic crucible at a temperature of 700 to 1200 ° C. for a short time.

  At this time, the amount of alkali silicofluoride mixed with talc is preferably in the range of 10 to 35% by mass of the entire mixture. If it is out of this range, the yield of swellable fluorinated mica tends to decrease.

  Next, the montmorillonite used as the swellable layered silicate is represented by the following formula, and can be obtained by refining a naturally produced product using a water treatment or the like.

_{M a Si (Al 2-a} Mg) O 10 (OH) 2 · nH 2 O
(In the formula, M represents a cation such as sodium, and 0.25 ≦ a ≦ 0.6. The number of water molecules bound to the ion-exchangeable cation between layers varies depending on conditions such as cation species and humidity. Therefore, it is expressed in nH ₂ O in the formula)
In addition, montmorillonite is known to have the same type of ion substitution product such as magnesia montmorillonite, iron montmorillonite, iron magnesia montmorillonite, and these may be used.

  In the present invention, there is no particular limitation on the initial particle size of the swellable layered silicate. Here, the initial particle diameter is the particle diameter of the swellable layered silicate as a raw material used in producing the polyamide resin composition (A) used in the present invention, and the silicate layer in the polyamide resin composition (A). It is different from the size of. However, this particle size also has a considerable influence on the physical properties of the obtained polyamide resin composition (A), in particular, rigidity and heat resistance. Therefore, when selecting the mixing ratio of the above-mentioned swellable layered silicate, it is desirable to take this point into account, and it is preferable to control the particle size by pulverizing with a jet mill or the like as necessary.

  Here, when the swellable fluoromica mineral is synthesized by the intercalation method, the initial particle size can be changed by appropriately selecting the particle size of talc as a raw material. This is a preferable method in that the initial particle diameter can be adjusted in a wider range by using in combination with pulverization.

  The polyamide resin in the polyamide resin composition (A) in the present invention is an amide bond containing aminocarboxylic acid, lactam or diamine and dicarboxylic acid (including a pair of salts thereof) as main raw materials in the main chain. It is a polymer having. Specific examples of the raw material include aminocarboxylic acid such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, paraaminomethylbenzoic acid and the like. Examples of the lactam include ε-caprolactam, ω-undecanolactam, and ω-laurolactam. Examples of diamines include tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, 2,4- Dimethyloctamethylenediamine, metaxylylenediamine, paraxylylenediamine, 1,3-bis (aminomethyl) cyclohexane, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2, There are 2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperazine and the like. Dicarboxylic acids include adipic acid, peric acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium Examples include sulfoisophthalic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid. These diamines and dicarboxylic acids can also be used as a pair of salts.

  Preferred examples of such polyamide resins include polycaproamide (nylon 6), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polycaproamide / polyhexamethylene adipa. Nylon copolymer (nylon 6/66), polyundecamide (nylon 11), polycaproamide / polyundecamide copolymer (nylon 6/11), polydodecamide (nylon 12), polycaproamide / polydodecamide copolymer (nylon 6/12) ), Polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polyundecamethylene adipamide (nylon 116), polyhexamethylene isophthalamide (nylon 6I), polyhexamethylene terephthalamide Nylon 6T), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polycaproamide / polyhexamethylene terephthalamide copolymer (nylon 6 / 6T), polycaproamide / polyhexamethylene isophthalamide copolymer (Nylon 6 / 6I), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (nylon 66 / 6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I), polytrimethylhexa Methylene terephthalamide (nylon TMDT), polybis (4-aminocyclohexyl) methane dodecamide (nylon PACM12), polybis (3-methyl-4-aminocyclohexyl) methane dodeca De (nylon dimethyl PACM12), poly-m-xylylene terephthalamide (nylon MXD6), polyundecamethylene terephthalamide (nylon 11T), and mixtures thereof or copolymers thereof. Of these, nylon 6 and nylon 66 are particularly preferable.

  In the present invention, the molecular weight (relative viscosity) of the polyamide resin is not particularly limited, but the relative viscosity measured under the conditions of 96 mass% concentrated sulfuric acid as a solvent at a temperature of 25 ° C. and a concentration of 1 g / dl is 1.5 to 5. It is desirable to be in the range of 0, particularly in the range of 2.0 to 4.0. When the relative viscosity is less than 1.5, the mechanical properties of the molded article tend to be lowered, and when the relative viscosity is more than 5.0, the moldability tends to be markedly lowered.

    The method for producing the polyamide resin composition (A) used in the present invention is basically prepared by adding a predetermined amount of monomer to an autoclave in the presence of an appropriately selected swellable layered silicate, and then using an initiator such as water. The melt polycondensation may be carried out within a range of temperatures of 240 to 300 ° C., pressure of 0.2 to 3 MPa, and 1 to 15 hours. When nylon 6 is used as the resin matrix, it is preferable to polymerize at a temperature of 250 to 280 ° C., a pressure of 0.5 to 2 MPa, and a range of 3 to 5 hours.

  In order to remove the polyamide monomer remaining in the polyamide resin composition after polymerization, it is preferable to scour the pellets of the polyamide resin composition with hot water. In this case, the treatment is preferably performed in hot water at 90 to 100 ° C. for 8 hours or more.

  The amount of the swellable layered silicate is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the polyamide resin component. If this compounding quantity is less than 0.1 mass part, the reinforcement effect by the silicate layer of swelling layered silicate is scarce. On the other hand, when the blending amount exceeds 20 parts by mass, it is difficult to dispense the polyamide resin composition (A) produced from the autoclave, which is not preferable because the yield is greatly reduced.

  Next, the biodegradable polyester resin (B) that forms the resin composition of the present invention together with the polyamide resin composition (A) will be described.

  In the present invention, examples of the biodegradable polyester resin (B) include poly (L-lactic acid), poly (D-lactic acid), polyglycolic acid, polycaprolactone, polybutylene succinate, and polyethylene succinate. Of these, poly (L-lactic acid), poly (D-lactic acid), and mixtures or copolymers thereof can be used from the viewpoints of heat resistance and moldability, but from the viewpoint of biodegradability, poly (L The main component is -lactic acid.

  The melting point of polylactic acid mainly composed of poly (L-lactic acid) varies depending on the optical purity, but in the present invention, the melting point is preferably 160 ° C. or higher in consideration of the mechanical properties and heat resistance of the molded body. In the polylactic acid mainly composed of poly (L-lactic acid), in order to make the melting point 160 ° C. or higher, the ratio of the D-lactic acid component may be less than about 3 mol%.

  The melt flow rate of the biodegradable polyester resin (B) at 190 ° C. and a load of 21.2 N is 0.1 to 50 g / 10 min, preferably 0.2 to 20 g / 10 min, more preferably 0.5 to 10 g / min. 10 minutes. When the melt flow rate exceeds 50 g / 10 min, the melt viscosity is too low, and the mechanical properties and heat resistance of the molded article are inferior. When the melt flow rate is less than 0.1 g / 10 minutes, the load during the molding process becomes too high, and the operability may be lowered.

  The biodegradable polyester resin (B) is usually produced by a known melt polymerization method or further using a solid phase polymerization method. As a method for adjusting the melt flow rate of the biodegradable polyester resin (B) to a predetermined range, when the melt flow rate is too large, a small amount of chain extender, for example, a diisocyanate compound, a bisoxazoline compound, Examples thereof include a method of increasing the molecular weight of the resin using an epoxy compound, an acid anhydride or the like. On the other hand, when the melt flow rate is too small, a method of mixing with a biodegradable polyester resin or a low molecular weight compound having a large melt flow rate can be used.

  The biodegradable polyester resin (B) in the present invention may contain a swellable layered silicate for the purpose of improving mechanical strength and heat resistance. The blending amount is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 10 parts by mass with respect to 100 parts by mass of the biodegradable polyester resin (B). Specific examples of the swellable layered silicate are as described above.

  The swellable layered silicate to be blended with the biodegradable polyester resin (B) is preferably pretreated with an organic cation. Examples of the organic cation include ammonium ions generated by protonation of primary to tertiary amines, onium ions such as quaternary ammonium ions and phosphonium ions. Examples of the primary amine include octylamine, dodecylamine, octadecylamine and the like. Examples of secondary amines include dioctylamine, methyloctadecylamine, and dioctadecylamine. Examples of the tertiary amine include trioctylamine, dimethyldodecylamine, didodecylmonomethylamine and the like. Examples of quaternary ammonium ions include tetraethylammonium, octadecyltrimethylammonium, dimethyldioctadecylammonium, dihydroxyethylmethyloctadecylammonium, methyldodecylbis (polyethyleneglycol) ammonium, methyldiethyl (polypropyleneglycol) ammonium and the like. Furthermore, examples of the phosphonium ion include tetraethylphosphonium, tetrabutylphosphonium, hexadecyltributylphosphonium, tetrakis (hydroxymethyl) phosphonium, 2-hydroxyethyltriphenylphosphonium, and the like. Of these, treatment with ammonium ions having one or more hydroxyl groups in the molecule, such as dihydroxyethyl methyl octadecyl ammonium, methyl dodecyl bis (polyethylene glycol) ammonium, methyl diethyl (polypropylene glycol) ammonium, 2-hydroxyethyl triphenylphosphonium, etc. The swellable layered silicate is particularly preferred because it has a high affinity with polyester resins, particularly biodegradable polyester resins, and improves the dispersibility of the swellable layered silicate. These cations may be used alone or in combination of two or more.

  As a method of treating the swellable layered silicate with the above organic cation, first, the swellable layered silicate is dispersed in water or alcohol, and the above organic cation is added thereto in the form of a salt and mixed by stirring. In this method, after the inorganic ions of the swellable layered silicate are ion-exchanged with the organic onium ions, they are filtered, washed and dried.

  When using the swellable layered silicate, a compatibilizing agent may be used in order to improve the dispersibility in the biodegradable polyester resin (B). The addition amount is preferably 0.01 to 10 parts by mass, more preferably 0.02 to 5 parts by mass with respect to 100 parts by mass of the biodegradable polyester resin (B). When the addition amount of the compatibilizing agent exceeds 10 parts by mass, the heat resistance and mechanical strength of the biodegradable polyester resin (B) may decrease. Examples of the compatibilizer include polyester resins, particularly biodegradable polyester resins (B), and polyalkylene oxides, aliphatic polyesters, polyhydric alcohol esters, polyhydric carboxylic acid esters, etc., which are compatible with both layered silicates. A compound is used.

  Examples of polyalkylene oxides include polyethylene glycol, polypropylene glycol, polybutylene glycol, and copolymers thereof, and one or two of the terminal hydroxyl groups may be alkoxy-blocked, and may be monocarboxylic acid or dicarboxylic acid. It may be esterified with an acid.

  Examples of aliphatic polyesters include polylactic acid, polyglycolic acid, poly (3-hydroxybutyric acid), poly (3-hydroxyvaleric acid), poly (3-hydroxycaproic acid) and other polyhydroxycarboxylic acids, poly (ε -Caprolactone), poly (ω-hydroxyalkanoate) represented by poly (δ-valerolactone), poly (ethylene succinate), poly (butylene succinate), poly (butylene succinate-co-butylene adipate), etc. And aliphatic polyesters composed of a diol and a dicarboxylic acid represented by In these aliphatic polyesters, the terminal carboxyl group may be esterified with an alcohol or may be hydroxyl-substituted with a diol.

  Examples of the polyhydric alcohol ester include glycerin esters such as monoglyceride, diglyceride and triglyceride which are esters of glycerin and fatty acid, pentaerythritol ester and the like. Examples of polyvalent carboxylic acid esters include citric acid esters such as tributyl citrate and tributyl citrate.

  The above compatibilizing agent preferably has a boiling point of 250 ° C. or higher. If the boiling point is less than 250 ° C., gas may be generated during molding or bleed out may occur from the resulting molded article. The number average molecular weight is preferably in the range of 200 to 50,000, more preferably 500 to 20,000. When the molecular weight of the compatibilizing agent is less than 200, gas may be generated during molding, bleeding out from the obtained molded body is likely to occur, and the mechanical strength and heat resistance of the molded body may be impaired. When the molecular weight exceeds 50,000, the effect of improving the dispersibility of the layered silicate tends to be reduced.

  As a method for adding a compatibilizer, a method of impregnating the above-mentioned compound directly into a swellable layered silicate in advance, or after mixing the above compound in the presence of water or an organic solvent, the water or the organic solvent is removed by filtration or the like. Methods, a method of adding a polyester resin and a swellable layered silicate at the time of melt kneading, a method of adding together with a swellable layered silicate at the time of synthesizing a polyester resin, etc. A method in which the layered silicate is mixed is preferably used.

  In order to impart hydrolysis resistance to the resin composition of the present invention, it is effective to add a carbodiimide compound within a range of 0.5 to 10 parts by mass with respect to 100 parts by mass of the biodegradable polyester resin (B). It is. If the addition amount of the carbodiimide compound is within the above-described range, the effect of improving the hydrolysis resistance is good, and there is no appearance defect of the molded product due to bleed-out of the carbodiimide compound, and no deterioration of mechanical properties due to plasticization.

    Specific examples of carbodiimide compounds preferably used in the present invention include poly (4,4′-diphenylmethanecarbodiimide), poly (p-phenylenecarbodiimide), poly (m-phenylenecarbodiimide), and poly (tolylcarbodiimide). ), Poly (diisopropylphenylenecarbodiimide), poly (methyl-diisopropylphenylenecarbodiimide), poly (triisopropylphenylenecarbodiimide), and the like, and monomers thereof. In this invention, a carbodiimide compound may be used independently or may be used in combination of 2 or more type.

  The resin composition of the present invention is obtained by melt-kneading the polyamide resin composition (A) and the biodegradable polyester resin (B), and the blending ratio of both is the polyamide resin composition (A ) 50 to 95% by mass and 50 to 5% by mass of the biodegradable polyester resin (B). When the blending amount of the polyamide resin composition (A) exceeds 95% by mass and the blending amount of the biodegradable polyester resin (B) is less than 5% by mass, it is not satisfactory in terms of reducing the use of exhausted resources, Molding with a polyamide resin composition (A) of less than 50% by mass and a biodegradable polyester resin (B) with an amount of more than 50% by mass deteriorates moldability and has sufficient rigidity and heat resistance. I can't get a body.

    In the resin composition of the present invention, mechanical strength such as impact strength is further improved by simultaneously melt-kneading the unsaturated carboxylic acid compound and / or the unsaturated epoxy compound. The blending amount of at least one of these unsaturated carboxylic acid compounds and unsaturated epoxy compounds is 0.05 with respect to 100 parts by mass in total of the polyamide resin composition (A) and the biodegradable polyester resin (B). -5 mass parts, especially 0.1-3 mass parts are preferred.

    Examples of the unsaturated carboxylic acid compound used in the present invention include acrylic acid, α-ethylacrylic acid, methacrylic acid, maleic acid, fumaric acid, halogenated maleic acid, citraconic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, halogen Citraconic acid, crotonic acid, halogenated crotonic acid, itaconic acid, halogenated itaconic acid, cis-4-cyclohexene-1,2-dicarboxylic acid, endo-bicyclo- (2,2,1) -5-heptene-2 , 3-dicarboxylic acid, methyl-endo-cis-bicyclo- (2,2,1) -5-heptene-2,3-dicarboxylic acid, endo-bicyclo- (2,2,1) -1,2,2 , 2,7,7-hexachloro-2-heptene-5,6-dicarboxylic acid, etc., and anhydrides of these unsaturated carboxylic acids It can be used esters, amides, imides, and metal salts.

    Specific examples of the unsaturated epoxy compound used in the present invention include glycidyl acrylate, glycidyl methacrylate, itaconic acid monoglycidyl ester, itaconic acid diglycidyl ester, butenetricarboxylic acid monoglycidyl ester, butenetricarboxylic acid diglycidyl ester, Butenetricarboxylic acid triglycidyl ester, p-styrene carboxylic acid glycidyl ester, allyl glycidyl ether, 2-methylallyl glycidyl ether, styrene-p-glycidyl ether, p-glycidyl styrene, 3,4-epoxy-1-butene, 3, 4-epoxy-3-methyl-1-butene, 3,4-epoxy-1-pentene, 3,4-epoxy-3-methyl-1-pentene, 5,6-epoxy-1-hexene and vinylcyclo Cyclohexene monoxide, and the like can be given.

    Examples of unsaturated carboxylic acid compounds and unsaturated epoxy compounds most preferably used in the present invention include maleic anhydride, endo-bicyclo- (2,2,1) -5-heptene-2,3-dicarboxylic acid anhydride. , Glycidyl acrylate, glycidyl methacrylate and the like.

    Moreover, in this invention, a radical generator can be added as needed at the time of melt-kneading with an unsaturated carboxylic acid compound and an unsaturated epoxy compound. Examples of radical generators include ketone peroxides, diacyl peroxides, hydroperoxides, dialkyl peroxides, peroxyketals, and other organic peroxides such as parachlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide. Oxide, tertiary butyl cumyl peroxide, ditertiary butyl peroxide, dicumyl peroxide, benzoyl peroxide, 2,5-dimethyl-2,5-di (tertiary butyl peroxy) hexyne, 2,5-dimethyl- 2,5-di (tertiary butyl peroxy) hexane, tertiary butyl hydroperoxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, acetyl peroxide Can be used octanoyl peroxide, 3,5,5 and trimethyl hexanoyl peroxide, azo compounds such as azobisisobutyronitrile. The blending amount of these radical generators is desirably less than 3 parts by mass with respect to 100 parts by mass in total of the polyamide resin composition (A) and the biodegradable polyester resin (B).

    The resin composition of the present invention is produced by melt-kneading a polyamide resin composition (A) containing a swellable layered silicate and a biodegradable polyester resin (B) at a predetermined ratio. As the melt kneading apparatus, a Banbury mixer, a roll mixer, a kneader, a single screw extruder, a multi-screw extruder, or the like can be used.

    In the resin composition of the present invention, other polymers may be further blended as necessary, as long as the characteristics are not significantly impaired. In this case, the blending amount is desirably 30 parts by mass or less with respect to 100 parts by mass of the resin composition. Such polymers include polystyrene, modified polyolefin, polycarbonate, polyarylate, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyetherimide, polyphenylene sulfide, polyphenylene ether, ABS, PMMA, polyvinyl chloride. , Phenoxy resin, liquid crystal polymer and the like.

    In addition, pigments, heat stabilizers, antioxidants, weathering agents, flame retardants, plasticizers, mold release agents, other reinforcing materials, etc. are added to the resin composition of the present invention as long as the properties are not significantly impaired. You can also Examples of such heat stabilizers and antioxidants include hindered phenols, phosphorus compounds, hindered amines, sulfur compounds, and copper compounds. Common benzophenones and benzotriazoles are used as the weathering agent. As the flame retardant, a general phosphorus flame retardant or a halogen flame retardant is used. Examples of reinforcing materials include clay, talc, calcium carbonate, zinc carbonate, wollastonite, silica, alumina, magnesium oxide, calcium silicate, asbestos, sodium aluminate, calcium aluminate, sodium aluminosilicate, magnesium silicate, aluminum hydroxide , Calcium hydroxide, barium sulfate, potassium light van, sodium light van, iron light van, glass balloon, carbon black, zinc oxide, antimony trioxide, boric acid, borax, zinc borate, zeolite, hydrotalcide, metal fiber, Metal whisker, ceramic whisker, potassium titanate whisker, boron nitride, mica, graphite, glass fiber, carbon fiber and the like can be mentioned.

  ADVANTAGE OF THE INVENTION According to this invention, the resin composition which was excellent in heat resistance and a moldability, and reduced the usage rate of a depleted resource is provided. And it becomes possible to use as a molded object useful in a motor vehicle, an electrical machinery, and another field | area using the outstanding performance.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited only to an Example.

In addition, the measuring method of the raw material and physical property test which were used by the Example and the comparative example is as follows.
1. Raw material (1) Swellable fluorinated mica (M-1)
To talc pulverized so as to have an average particle size of 4.0 μm by a ball mill, sodium silicofluoride having an average particle size of 10 μm was mixed so as to be 15% by mass of the total amount. This was put in a magnetic crucible and reacted at 850 ° C. for 1 hour in an electric furnace to obtain a swellable fluorine mica (M-1) having an average particle size of 4.0 μm. The composition of this swellable fluorinated mica was Na _0.60 Mg _2.63 Si ₄ O ₁₀ F _1.77 , and the cation exchange capacity obtained by the measurement method described later was 110 meq / 100 g.
(2) Swellable fluorine mica (M-2)
A swellable fluoromica in which the interlayer ions are substituted by dispersing the interlayer of M-1 in water, adding dihydroxyethylmethyldodecylammonium salt, stirring and mixing, filtering and drying.
(3) Polyamide resin (A-2)
Unitika nylon 6 resin “A1030BRL” was used. The relative viscosity by viscosity measurement described later was 2.5.
(4) Biodegradable polyester resin: Polylactic acid (L-2)
Cargill Dow NatureWorks 4030D; MFR = 3.0, melting point 166 ° C. was used.
(5) Unsaturated compound Maleic anhydride (manufactured by NOF Corporation) was used.
(6) Radical generator 2,5-dimethyl-2,5-di (tertiary butyl peroxy) hexyne (manufactured by NOF Corporation) was used.
2. Measuring method (1) Cation exchange capacity (milli equivalent / 100 g)
It calculated | required based on the cation exchange capacity | capacitance measuring method (JBAS-106-77) of bentonite (powder) by the Japan Bentonite Industry Association standard test method.

That is, using a device in which a leachate container, a leach tube, and a receiver are connected in the vertical direction, first, all of the ion-exchangeable cations between the layers are made with a 1N ammonium acetate aqueous solution in which the layered silicate is adjusted to pH = 7. Is replaced with NH ₄ ⁺ . Then, after thoroughly washing with water and ethyl alcohol, the NH ₄ ⁺ type layered silicate is immersed in a 10% by mass potassium chloride aqueous solution, and NH ₄ ⁺ in the sample is exchanged for K ⁺ . To do. Subsequently, by neutralizing titrating NH ₄ ⁺ leached with the above-described ion exchange reaction with a 0.1N aqueous sodium hydroxide solution, the cation exchange capacity of the swellable layered silicate as a raw material (milli equivalent / 100 g).
(2) Inorganic ash content (mass%) of polyamide resin and biodegradable polyester resin
The dry pellets of polyamide resin and biodegradable polyester resin were precisely weighed in a magnetic crucible, and the residue after incineration for 15 hours in an electric furnace maintained at 500 ° C. was used as the inorganic ash, and the inorganic ash content was determined according to the following formula.
Inorganic ash (mass%) = {Inorganic ash mass (g)} / {Total mass of sample before incineration (g)} × 100
(3) Relative viscosity of polyamide resin In 96 mass% concentrated sulfuric acid, a dry pellet of the polyamide resin composition was dissolved so as to have a concentration of 1 g / dl, and the inorganic component was filtered off with a G-3 glass filter. It used for the measurement. The measurement was performed at 25 ° C. using an Ubbelohde viscometer.
(4) Melt flow rate (MFR)
According to JIS standard K-7210 (test condition 4), it measured at 190 degreeC and the load 21.2N.
(5) Flexural modulus:
In accordance with ASTM standard D-790, a load was applied at a deformation rate of 1 mm / min, and the flexural modulus was measured.
(6) Impact strength Izod impact strength was measured using a test piece with a notch (V-shaped notch) according to ASTM standard D-256.
(7) Deflection temperature under load According to ASTM standard D-648, the load was measured at a load of 0.45 MPa.
(8) Moldability ASTM test dumbbell pieces (thickness 3 mmt) were molded with an injection molding machine at a cylinder temperature of 230 ° C. and a mold temperature of 80 ° C., and deformation at the time of mold release was evaluated. Specifically, ◎ indicates that the mold was successfully released in a molding cycle of less than 40 seconds, ○ indicates that the mold was successfully released in 40 to 60 seconds, and x indicates that the mold could not be released satisfactorily even if 60 or more.
[Reference Example 1] Polyamide resin (A-1)
400 g of swellable fluorinated mica M-1 (total cation exchange capacity corresponds to 0.44 mol) is added to a solution obtained by mixing 1 kg of ε-caprolactam and 1 kg of water, and at room temperature, using a homomixer. And stirred for 1.5 hours. The total amount of the swellable fluorinated mica dispersion was previously charged with 9 kg of ε-caprolactam and 50.7 g (0.44 mol) of 85 mass% phosphoric acid aqueous solution, and melted at 95 ° C. The mixture was put into an autoclave, heated to 260 ° C. with stirring, and the pressure was increased to 0.7 MPa. Thereafter, while gradually releasing water vapor, the temperature of 260 ° C. and the pressure of 0.7 MPa was maintained for 1 hour, and the pressure was released to normal pressure over 1 hour, followed by polymerization for 30 minutes.

  When the polymerization was completed, the reaction product was discharged into a strand, cooled and solidified, and then cut to obtain a pellet made of a polyamide resin composition. Next, the pellets were refined with hot water at 95 ° C. for 8 hours and then dried.

The content of the silicate layer in A-1 as measured by the inorganic ash content was 4.2% by mass. The relative viscosity was 2.7.
[Reference Example 2] Biodegradable polyester resin (L-1)
Using a twin-screw extruder (TEM-37BS manufactured by Toshiba Machine Co., Ltd.), 96% polylactic acid (L-2) and 4% swellable fluorinated mica (M-2) were melt-kneaded at a temperature of 230 ° C. and pelletized. Later it was dried. The content of the silicate layer in L-1 by ash measurement was 2.7% by mass.
Example 1
After mixing the raw materials with the composition shown in Table 1, the mixture was melt-kneaded at a temperature of 230 ° C. and pelletized using a twin-screw extruder (TEM-37BS manufactured by Toshiba Machine Co., Ltd.). The obtained pellets were dried, and test pieces were injection-molded using an IS-100 molding machine manufactured by Toshiba Machine Co., Ltd., and subjected to tests. Table 1 shows the measurement results of various physical properties.
Examples 2 and 3
Raw material mixed with biodegradable polyester resin, unsaturated compound and radical generation is fed from the base of the twin screw extruder through the side feeder with the polyamide resin in the middle of the cylinder, melt kneaded at 230 ° C, pellets Turned into. The obtained pellets were dried, and test pieces were injection-molded using an IS-100 molding machine manufactured by Toshiba Machine Co., Ltd., and subjected to tests. Table 1 shows the measurement results of various physical properties. The composition is shown in Table 1.
Comparative Examples 1 and 2
A test piece was injection molded in the same manner as in Example 1 except that the composition of the raw materials was changed as shown in Table 1, and various physical properties of the test piece were evaluated. Table 1 shows the evaluation results of various physical properties of the test pieces obtained in Comparative Examples 1 and 2.

As can be seen from Table 1, in Examples 1, 2 and 3, it was possible to obtain molded articles having good rigidity, heat resistance and moldability and capable of withstanding actual use.

On the other hand, in Comparative Example 1, since a normal polyamide resin not containing a swellable layered silicate was used, heat resistance was inferior and moldability was slightly inferior. Moreover, since the compounding ratio of the biodegradable polyester resin (B) exceeded the range of this invention, the comparative example 2 was inferior in a moldability and all the physical properties.

Claims (4)

  50 to 95% by mass of a polyamide resin composition (A) in which a silicate layer of 0.1 to 20 parts by mass of a swellable layered silicate is dispersed in 100 parts by mass of a polyamide resin, and a biodegradable polyester resin (B) A resin composition obtained by melt-kneading 50 to 5% by mass.   A total of 100 parts by mass of the polyamide resin composition (A) and the biodegradable polyester resin (B) is blended with 0.05 to 5 parts by mass of an unsaturated carboxylic acid compound and / or an unsaturated epoxy compound (C). The resin composition according to claim 1.   3. The resin composition according to claim 1, wherein the biodegradable polyester resin (B) is polylactic acid. The biodegradable polyester resin (B) is characterized in that 0.1 to 20 parts by mass of a swellable layered silicate silicate layer is dispersed in 100 parts by mass of the biodegradable polyester resin (B). Item 4. The resin composition according to any one of Items 1 to 3.