JP2009035592A - Glass fiber-reinforced polyamide resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyamide resin composition having sufficient mechanical properties, low warpage property and welding strength as a thin molded product, and to provide a polyamide resin composition having appropriate physical properties for a member to which strength is required although the member is thin such as automobile parts and housings and chassis of electronic equipment. <P>SOLUTION: The polyamide resin composition is prepared by compounding 10 to 50 parts by mass of flat glass fibers having a flat cross section with a major axis/minor axis ratio of 1.5 to 10 into 100 parts by mass of polyamide resin comprising dispersion of silicate layers of a swelling sheet silicate, wherein 0.05 to 4.0 part by mass of an organic compound having two or more functional groups in one molecule is compounded into the polyamide resin composition. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a glass fiber reinforced polyamide resin composition that is excellent in rigidity and can be formed into a low warp molded article.

  Polyamide resins are widely used particularly as injection molding materials for automobile parts, housings for electronic devices, and the like, because the molded products have excellent mechanical properties. When giving high rigidity and heat resistance to a polyamide molded product, a polyamide resin composition reinforced with a fibrous reinforcing material is usually used, and a polyamide resin containing a specific amount of glass fiber as the fibrous reinforcing material Compositions have been proposed. However, the polyamide resin composition has a problem that when it is molded by injection molding, the warp of the molded product is large and the dimensional stability is low.

  Further, it has been proposed to improve warpage and deformation of a molded product by adding glass fiber and powdered inorganic substances such as talc to polyamide resin. However, in the polyamide resin composition described here, the amount of glass fiber added is 15% by mass or less and the amount of inorganic material added is 20% by mass or more. It was difficult to improve rigidity, strength, impact resistance, weld strength, and the like.

  Furthermore, a low warp polyamide resin composition comprising a reinforced polyamide resin in which montmorillonite is uniformly dispersed at a molecular level and a fibrous reinforcing material has been proposed. However, even in this case, when the glass fiber content is large, the warping improvement effect was not sufficient.

Patent Document 1 below describes a reinforced polyamide resin in which a swellable fluorinated mica-based mineral is uniformly dispersed as a method capable of forming a molded article having high rigidity, excellent heat resistance and impact resistance, and low warpage. A polyamide resin composition comprising a fibrous reinforcement is described.
Japanese Patent No. 3542469

  The problem to be solved by the present invention is to provide a polyamide resin composition having sufficient mechanical properties, low warpage, and weld strength as a thin-walled molded article. An object of the present invention is to provide a polyamide resin composition having appropriate physical properties for such a thin member that requires strength.

  As a result of intensive studies in order to solve such problems, the present inventors have found that a specific resin composition solves the problems, and have completed the present invention.

That is, the gist of the present invention is as follows.
(1) 10 to 50 mass of flat glass fibers having a flat cross section with a major axis / minor axis ratio of 1.5 to 10 with respect to 100 parts by mass of the polyamide resin in which the silicate layer of the swellable layered silicate is dispersed. Part of a polyamide resin composition, wherein 0.05 to 4.0 parts by mass of an organic compound having two or more functional groups in one molecule is added to the polyamide resin composition. A characteristic polyamide resin composition.
(2) The organic compound of (1) is at least one organic compound selected from trimethylolpropane polyglycidyl ether, polyglycerin polyglycidyl ether, triglycidyl isocyanurate, and styrene / maleic anhydride copolymer. A characteristic polyamide resin composition.
(3) A glass fiber reinforced polyamide resin composition, wherein the polyamide resin according to any one of (1) to (2) is one kind of polyamide selected from nylon 6, nylon 66, and nylon 11.
(4) The flat glass fiber according to any one of (1) to (3) is a glass fiber having a deformed cross-sectional shape of any one of a gourd type, an eyebrows type, an oval type, an elliptical type, and a rectangular type, A glass fiber reinforced polyamide resin composition obtained by surface-treating with one or more coupling agents selected from silane coupling agents, titanium coupling agents, and zirconia coupling agents.
(5) A resin molded product obtained by molding the glass fiber reinforced polyamide resin composition according to any one of (1) to (4).

  The polyamide resin composition of the present invention is excellent in dimensional stability because it has sufficient mechanical properties and low warpage and weld strength when molding thin parts such as housings and chassis of automobile parts and electronic devices. A robust resin molded product can be obtained, and the industrial utility value is extremely high.

  Hereinafter, the present invention will be described in detail.

  The polyamide resin in the present invention is obtained by dispersing a silicate layer of a swellable layered silicate in a polyamide resin matrix.

  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”). .

  It is preferable that the silicate layer is uniformly dispersed in the polyamide resin at the molecular level. “Uniformly dispersed at the molecular level” means that when the silicate layer of the swellable layered silicate is dispersed in the polyamide resin, each of them keeps an average interlayer distance of 1 nm or more without forming a lump with each other. The state that exists. Here, the lump refers to a state where the swellable layered silicate as a raw material is not cleaved. The interlayer distance is the distance between silicate layers. The dispersion state of the silicate layer in the polyamide resin can be confirmed, for example, by observation with a transmission electron microscope.

  Note that the silicate layers do not necessarily have to be separated one by one, and the silicate layers may be partially laminated.

  The swellable lamellar silicate used in the present invention has a structure composed of a negatively charged crystal layer mainly composed of silicate and a cation having ion exchange ability interposed between the layers, and will be described later. It is desirable that the cation exchange capacity determined in (1) 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 uncleaved state, and the performance of the polyamide composite material is insufficiently improved. There is a case. The upper limit of the value of the cation exchange capacity is not particularly limited, but the upper limit of the cation exchange capacity of the swellable layered silicate that can be actually obtained or prepared is about 250 meq / 100 g.

  The swellable layered silicate used in the present invention may be naturally produced or artificially synthesized or modified, for example, smectite group (montmorillonite, beidellite, hectorite, soconite, etc.), vermiculite group (vermiculite). Etc.), mica (fluorine mica, muscovite, paragonite, phlogopite, lepidrite, etc.), brittle mica (margarite, clintonite, anandite, etc.), chlorite (donbasite, sudite, kukeite, clinochlore, chamosite) In the present invention, Na type or Li type swellable fluorinated mica or montmorillonite is particularly preferably used.

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

M _a (Mg _X Li _b ) Si ₄ O _Y F _Z
(In the formula, M represents an ion-exchangeable cation, specifically sodium or lithium. A, b, X, Y and Z each represents a coefficient, and 0 ≦ a ≦ 0.5. 0 ≦ b ≦ 0.5, 2.5 ≦ X ≦ 3, 10 ≦ Y ≦ 11, 1.0 ≦ Z ≦ 2.0)
As such swellable fluorine mica, commercially available products from Co-op Chemical Co., Ltd. and Topy Industries, Ltd. can be suitably used, and they can be easily obtained by the following production method.

  That is, silicon oxide, magnesium oxide and various fluorides are mixed, and the mixture is completely melted at a temperature of 1400 to 1500 ° C. in an electric furnace or gas furnace, and fluorinated mica is crystallized in the reaction vessel in the cooling process. This is a so-called melting method for growth. Further, there is a method in which talc is used as a starting material, and alkali metal ions are intercalated to obtain fluorine mica. In the latter method, fluorinated mica can be obtained by mixing talc with silicofluoride alkali or alkali fluoride, and heat-treating at 700 to 1200 ° C. for a short time in a magnetic crucible.

  At this time, the amount of alkali silicofluoride or alkali fluoride to be mixed with talc is preferably in the range of 10 to 35% by mass of the whole mixture. This is not preferable because the yield decreases.

  In order to obtain the above-described swellable fluoromica-based mineral, the alkali metal fluorosilicate or alkali metal of alkali fluoride must be sodium or lithium. These alkali metals may be used alone or in combination. In addition, among alkali metals, in the case of potassium, a swellable fluoromica-based mineral cannot be obtained, but it can be used in combination with sodium or lithium, and for the purpose of adjusting the swellability in a limited amount. It is.

  Furthermore, in the process of producing the swellable fluoromica-based mineral, it is also possible to adjust the swelling property of the swellable fluoromica-based mineral to be produced by blending a small amount of alumina.

  When the swellable fluoromica mineral is synthesized by an 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 montmorillonite that can be used in the present invention is represented by the following formula, and can be obtained by refining a naturally produced product by 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. Further, the number of water molecules bonded to the ion-exchangeable cation between layers depends on conditions such as cation species and humidity. (It is expressed as 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.

  The initial particle size of the swellable layered silicate used in the present invention is not particularly limited, but is appropriately selected in consideration of the influence on the rigidity and heat resistance of the obtained polyamide resin composition. The preferred particle size range is about 0.1 to 20 μm. The initial particle size can be controlled by pulverizing with a jet mill or the like, if necessary. The initial particle size referred to here is the particle size of the swellable layered silicate as a raw material used when producing the polyamide resin used in the present invention, and is different from the size of the silicate layer in the composite material. .

  The polyamide resin constituting the reinforced polyamide resin in the present invention means a polymer having an amide bond formed from an amino acid, lactam or diamine and a dicarboxylic acid (including a pair of salts thereof).

  Examples of monomers that form such polyamide resins include the following. Examples of amino acids include 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, paraaminomethylbenzoic acid and the like. Examples of the lactam include ε-caprolactam and ω-laurolactam. Examples of diamines include tetramethylene diamine, hexamethylene diamine, undecamethylene diamine, dodecamethylene diamine, 2,2,4- / 2,4,4-trimethylhexamethylene diamine, 5-methylnonamethylene diamine, and 2,4-dimethyl. Octamethylenediamine, metaxylylenediamine, paraxylylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis (4-aminocyclohexyl) methane, There are bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperazine and the like. Dicarboxylic acids include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5- Examples include sodium sulfoisophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, and diglycolic acid. These diamines and dicarboxylic acids can also be used as a pair of salts.

  Preferred examples of the polyamide resin include polycaproamide (nylon 6), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610), poly Hexamethylene dodecane (nylon 612), polyundecane methylene adipamide (nylon 116), polyundecanamide (nylon 11), polydodecanamide (nylon 12), polytrimethylhexamethylene terephthalamide (nylon TMDT), polyhexa Methylene isophthalamide (nylon 6I), polyhexamethylene terephthalate / isophthalamide (nylon 6T / 6I), polybis (4-aminocyclohexyl) methane dodecamide (nylon PACM12), polybis (3-methyl-4-amino) Rohexyl) methane dodecamide (nylon dimethyl PACM12), polymetaxylylene adipamide (nylon MDX6), polyundecamethylene terephthalamide (nylon 11T), polyundecamethylene hexahydroterephthalamide [nylon 11T (H)] or these Copolyamide, mixed polyamide, and the like. Among them, nylon 6, nylon 46, nylon 66, nylon 11, nylon 12, or a copolymer polyamide thereof, and a mixed polyamide are preferable, and nylon 6 or nylon 11 or a copolymer polyamide thereof is particularly preferable.

  Next, the manufacturing method of the polyamide resin in this invention is demonstrated.

  The production method of the polyamide resin is basically a method in which a predetermined amount of monomer is charged into an autoclave in the presence of an appropriately selected swellable layered silicate, and then an initiator such as water is used. The melt polycondensation method may be performed within the range of 0.2 to 3 MPa and 1 to 15 hours. When nylon 6 is used as the resin matrix, it is preferable to perform polymerization at a temperature of 240 to 300 ° C, a pressure of 0.2 to 3 MPa, and a range of 1 to 5 hours.

  Next, the temperature is maintained at the above-mentioned temperature, and the pressure is once returned to normal pressure. Then, the produced reinforced polyamide resin is discharged in the form of a strand, cooled, solidified and then cut into pellets of reinforced polyamide resin.

  Further, an acid may be added during the above polymerization, and by adding an acid, a molded product having higher rigidity and higher heat resistance can be obtained.

  The acid may be an organic acid or an inorganic acid if pKa (25 ° C., value in water) is 0 to 4 or a negative acid. For example, benzoic acid, sebacic acid, formic acid, acetic acid Monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, nitrous acid, nitric acid, phosphoric acid, phosphorous acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, perchloric acid, fluorosulfonic acid-pentafluoro Examples thereof include antimony (1: 1) [“Magic Acid” (registered trademark)] manufactured by Aldrich, and fluoroantimonic acid.

  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 of 90 to 100 ° C. for 8 hours or more.

  The polyamide resin can also be produced by melt-kneading a swellable layered silicate that has been pretreated with a swelling agent and a polyamide resin. The swelling agent is preferably an organic cation, and examples include organic ammonium ions and organic phosphonium ions. Examples of organic ammonium ions include primary to quaternary ammonium ions. Examples of the primary ammonium ion include octyl ammonium, dodecyl ammonium, octadecyl ammonium and the like. Secondary ammonium ions include dioctyl ammonium, methyl octadecyl ammonium, dioctadecyl ammonium and the like. Examples of tertiary ammonium ions include trioctylammonium, dimethyldodecylammonium, didodecylmonomethylammonium and the like. Quaternary ammonium ions include tetraethylammonium, trioctylmethylammonium, octadecyltrimethylammonium, dioctadecyldimethylammonium, dodecyldihexylmethylammonium, dihydroxyethylmethyloctadecylammonium, methyldodecylbis (polyethylene glycol) ammonium, and methyldiethyl (polypropylene glycol) ammonium. Etc. Examples of organic phosphonium ions include tetraethylphosphonium, tetrabutylphosphonium, tetrakis (hydroxymethyl) phosphonium, 2-hydroxyethyltriphenylphosphonium, and the like. These compounds may be used alone or in combination of two or more. Of these, ammonium ions are preferably used.

  As a method of treating the layered silicate with the organic cation, first, the layered silicate is dispersed in water or alcohol, and then the organic cation is added in the form of a salt and mixed by stirring to form the layered silicate. Examples of the method include ion-exchange of the inorganic ions with organic cations, followed by filtration, washing, and drying.

  The content of the silicate layer of the swellable layered silicate is preferably 0.1 to 20% by mass, and preferably 1.0 to 10% by mass with respect to 100% by mass of the polyamide resin including the silicate layer. Is more preferable, and it is still more preferable to set it as 1.5-5.0 mass%. This amount can be confirmed by the inorganic ash content of the polyamide resin described later. When the blending amount is less than 0.1% by mass, the reinforcing effect of the polyamide resin matrix by the silicate layer of the swellable layered silicate is poor. On the other hand, when the blending amount exceeds 20% by mass, the toughness tends to decrease, which is not preferable.

  The relative viscosity of the polyamide resin constituting the reinforced polyamide resin of the present invention is a range of 1.5 to 5.0 when 96 mass% concentrated sulfuric acid is used as a solvent, the temperature is 25 ° C., and the concentration is 1 g / dl. It is preferable that it exists in. When the relative viscosity is less than 1.5, the mechanical properties when formed into a molded product are lowered. On the other hand, when the relative viscosity exceeds 5.0, the moldability of the resin composition is rapidly lowered, which is not preferable.

  The glass fiber in the present invention is a component that can be made into a molded product having excellent rigidity and low warpage by being blended with a reinforced polyamide resin. The blending amount of the glass fiber needs to be 10 to 50 parts by mass with respect to 100 parts by mass of the reinforced polyamide resin. If the blending amount is 10 parts by mass or less, the reinforcing effect is not sufficient, and if it exceeds 50 parts by mass, the fluidity of the resin composition is lowered, the surface of the molded product is not finished smoothly, and the appearance is excellent. It cannot be a molded product.

  The glass fiber in the present invention is produced by a known method for producing glass fiber, and includes a silane coupling agent, a titanium-based coupling agent, a zirconia-based coupling agent, etc. in order to improve adhesion with a matrix resin and uniform dispersibility. The glass fiber strands that have been bundled by a known sizing agent suitable for a resin containing at least one coupling agent, an antistatic agent, a film forming agent, and the like are collected and cut to a certain length. Used in the form of chopped strands.

  The cross-section of the flat glass fiber used in the present invention needs to be a gourd type, eyebrow type, oval type, elliptical type, rectangular shape or the like. The flat glass fiber preferably has a major axis / minor axis ratio of 1.5 to 10, more preferably 2.0 to 6.0. When the major axis / minor axis ratio is 1.5 or less, since the cross section is nearly circular, the effect of suppressing warpage of the molded product is low. In addition, it is difficult to manufacture glass fibers themselves when the number is 10 or more.

  The blending amount of the polyamide resin and the flat glass fiber is preferably 10 to 50 parts by mass and more preferably 20 to 40 parts by mass with respect to 100 parts by mass of the polyamide resin. When the amount of the flat glass fiber is 20 parts by mass or less, the warp increases, which is not preferable. On the other hand, when the blending amount of the flat glass fiber exceeds 50 parts by mass, the flow characteristics deteriorate, it becomes impossible to take up the strand at the time of resin melt kneading, and it is difficult to produce a glass fiber reinforced polyamide resin composition. .

  As an organic compound having two or more functional groups in one molecule used in the present invention, the functional group has a plurality of epoxy groups, acid anhydride groups, oxazoline groups, carboxylic acid groups, amino groups, and isocyanate groups. Can be illustrated. Among them, compounds having an epoxy group such as glycidyl ether compounds such as trimethylolpropane polyglycidyl ether and polyglycerin polyglycidyl ether, glycidyl cyanurate compounds such as triglycidyl isocyanurate, styrene / maleic anhydride copolymers, etc. A compound having an acid anhydride group as a pendant can be suitably used.

  The compounding quantity of the organic compound which has a 2 or more functional group in 1 molecule is 0.05-4.0 mass parts with respect to 100 mass parts of polyamide resin compositions, Preferably it is 0.1-3. It is desirable that the content be 0 parts by mass, optimally in the range of 0.2 to 2.0 parts by mass. When the blending amount is 0.05 parts by mass or less, the improvement of the weld strength of the thermoplastic resin composition is insufficient, which is not preferable. On the other hand, when the blending amount exceeds 4.0 parts by mass, the fluidity of the thermoplastic resin composition is lowered, the molding processability is deteriorated, and the mechanical properties tend to be lowered. In addition, the dimensional stability of the molded product tends to deteriorate, and the amount of warpage is particularly large, which is not preferable.

  As a method for producing the polyamide resin composition of the present invention, for example, using a twin screw extruder, a predetermined amount of polyamide resin is supplied from the feed hole (top feed) located on the most upstream side, and the polyamide resin is When the molten state is reached, a predetermined amount of organic compound is supplied from the liquid injection hole using a liquid injection meter. Further, it is obtained by supplying a predetermined amount of flat glass fiber from a side feed, forming it into a strand shape by a spinning hole attached to the tip on the downstream side of the extruder, and then cooling and cutting it into a pellet shape.

  Further, the thermoplastic resin composition of the present invention may be mixed with other thermoplastic polymers. In this case as well, it is preferable to mix and alloy using a twin screw extruder equipped with a screw. . In such a resin composition, since the swellable layered silicate is uniformly dispersed in the polyamide resin at the molecular level, mechanical strength and heat resistance are improved as compared with an alloyed product with an unreinforced polyamide resin.

  Examples of the thermoplastic polymer include polybutadiene, butadiene / styrene copolymer, acrylic rubber, ethylene / propylene copolymer, ethylene / propylene / diene copolymer, natural rubber, chlorinated butyl rubber, and chlorinated polyethylene. Elastomers or their acid-modified products such as maleic anhydride, styrene / maleic anhydride copolymer, styrene / phenylmaleimide copolymer, polyethylene, polypropylene, butadiene / acrylonitrile copolymer, polyvinyl chloride, polyethylene terephthalate, polybutylene Terephthalate, polyacetal, polyvinylidene fluoride, polysulfone, polyphenylene sulfide, polyethersulfone, phenoxy resin, polyphenylene ether, polymethyl methacrylate, polyether Tons, polycarbonate, polytetrafluoroethylene, etc. polyarylate and the like. At this time, the thermoplastic polymer is preferably mixed at a ratio of 60 parts by mass or less with respect to 100 parts by mass of the polyamide resin.

  In the polyamide resin composition of the present invention, pigments, heat stabilizers, antioxidants, deterioration inhibitors, weathering agents, flame retardants, plasticizers, mold release agents, and the like are added as long as the properties are not greatly impaired. These may be added when the reinforced polyamide resin is polymerized or when the obtained polyamide resin composition is melt-kneaded or melt-molded.

  As the heat stabilizer, antioxidant, and deterioration inhibitor, for example, hindered phenols, phosphorus compounds, hindered amines, sulfur compounds, copper compounds, alkali metal halides, or mixtures thereof can be used.

  The relative viscosity of the obtained polyamide resin composition is within a range of 1.8 to 4.5, with a relative viscosity measured at 96 ° C. using concentrated sulfuric acid as a solvent and at a temperature of 25 ° C. and a concentration of 1 g / dl. Preferably, it is in the range of 2.0 to 3.5. When the relative viscosity is less than 1.8, the bending elastic modulus is inferior. On the other hand, when it exceeds 4.5, the fluidity at the time of melting of the polyamide resin composition is extremely lowered, which tends to impair the moldability. The glass fiber having a flat cross section used in the present invention is a fiber having a general glass fiber composition such as E glass, but any composition can be used as long as the glass fiber can be used. It is not limited.

  The polyamide resin composition of the present invention can be formed into a desired molded product by a normal molding method, for example, various molded products by a hot melt molding method such as injection molding, extrusion molding, blow molding, or an organic solvent. A thin film can be formed by casting from a solution.

  As the above molded products, pipes, hollow pipes, handles, ink containers, curtain rails, gear parts, bearing retainers, brushes, reels, breaker covers, switches, connectors, automotive exterior parts, automotive interior parts, light covers, Intake manifolds, timing belt covers, wheels, engine covers, cylinder head covers, housings and chassis for office machines / electronic devices, and the like. However, the present invention is not limited to these, and can be widely used in fields where the low warpage, mechanical strength and heat resistance, which are the characteristics of the polyamide resin composition of the present invention, can be utilized.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In addition, the raw material used for the Example and the comparative example and the physical property measuring method are as follows.
1 Raw Material (A) Polyamide Resin The following polyamides A to E were prepared as polyamide resins for use in the polyamide resin composition of the present invention. For each polyamide resin, the blending amount (actual amount) of the silicate layer was calculated as the inorganic ash content, and the relative viscosity and the dispersion state of the silicate layer were also confirmed. The results are shown in Table 1.

(1) Polyamide resin A
To 10 kg of ε-caprolactam, 1 kg of water and 200 g of swellable fluorinated mica (ME-100 manufactured by Corp Chemical Co., Ltd., cation exchange capacity 100 milliequivalent / 100 g, particle size 4 μm) were added, The mixture was placed in a 30 liter autoclave and heated to 260 ° C. until the internal pressure reached 1.5 MPa. Then, while gradually releasing water vapor, polymerization was performed for 2 hours while maintaining the pressure at 1.5 MPa and the temperature at 260 ° C., then, the pressure was released to normal pressure over 1 hour, and polymerization was further performed for 30 minutes. When the polymerization was completed, the reaction product was discharged into a strand shape, cooled, solidified, and then cut to obtain polyamide resin pellets. Next, the pellets were scoured with hot water at 95 ° C. for 8 hours and then vacuum-dried. The obtained polyamide resin had a silicate layer of 2.2% by mass as measured by inorganic ash content, and a relative viscosity of 2.7 by a viscosity measurement method described later. Further, when the wide angle X-ray diffraction measurement was performed on the polyamide resin pellet, the peak in the thickness direction of the fluorine mica completely disappeared, and the fluorine mica was uniformly dispersed in the polyamide resin at the molecular level. I understood.
(2) Polyamide resin B
To 10 kg of ε-caprolactam, 1 kg of water and 400 g of montmorillonite (Kunipia F, Kunipia F, cation exchange capacity 115 meq / 100 g, particle size 1 μm) were added, and this was added to an autoclave having an internal volume of 30 liters. And heated to 260 ° C. until the internal pressure reached 1.5 MPa. Thereafter, while gradually releasing water vapor, polymerization was performed for 2 hours while maintaining the pressure at 1.5 MPa and the temperature at 260 ° C., then, the pressure was released to normal pressure over 1 hour, and polymerization was further performed for 15 minutes. When the polymerization was completed, the reaction product was discharged into a strand shape, cooled, solidified, and then cut to obtain polyamide resin pellets. Next, the pellets were scoured with hot water at 95 ° C. for 8 hours and then vacuum-dried. The obtained polyamide resin had a silicate layer of 4.0% by mass and a relative viscosity of 2.5 by a viscosity measurement method described later. When the wide angle X-ray diffraction measurement was performed on the polyamide resin pellets, the peak in the thickness direction of montmorillonite disappeared completely, and it was found that montmorillonite was uniformly dispersed in the polyamide resin at the molecular level.
(3) Polyamide resin C
95% by mass of a polyamide resin (P-1) to be described later, 5% by mass of dodecyldihexylmethylammonium swelling treated swellable layered silicate (MEE manufactured by Coop Chemical Co., Ltd., particle size 8 μm), co-directional twin screw extruder (Toshiba Machine) The resin composition, which was supplied to the main supply port of TEM37BS manufactured and melted and kneaded, and taken up in a strand form from the die, was cooled and solidified through a water tank, and was cut with a pelletizer to obtain pellets of the resin composition. The extrusion conditions were a temperature setting of 250 to 260 ° C., a screw rotation speed of 200 rpm, and a discharge rate of 15 kg / h. The silicate layer was 3.5% by mass, and the relative viscosity by a viscosity measurement method described later was 2.5. When the wide angle X-ray diffraction measurement was performed on the polyamide resin pellets, the peak in the thickness direction of montmorillonite disappeared completely, and it was found that montmorillonite was uniformly dispersed in the polyamide resin at the molecular level.
(4) Polyamide resin D
Polyamide resin (P-2) described later in 94% by mass, dodecyldihexylmethylammonium swelling treatment swellable layered silicate (MEE manufactured by Co-op Chemical Co., Ltd., particle size 8 μm), 6% by mass, same-direction twin screw extruder (Toshiba Machine) The resin composition, which was supplied to the main supply port of TEM37BS manufactured and melted and kneaded, and taken up in a strand form from the die, was cooled and solidified through a water tank, and was cut with a pelletizer to obtain pellets of the resin composition. The extrusion conditions were a temperature setting of 270 to 290 ° C., a screw rotation speed of 200 rpm, and a discharge rate of 15 kg / h. The silicate layer was 4.2% by mass, and the relative viscosity measured by the viscosity measurement method described later was 2.8. When the wide angle X-ray diffraction measurement was performed on the polyamide resin pellets, the peak in the thickness direction of montmorillonite disappeared completely, and it was found that montmorillonite was uniformly dispersed in the polyamide resin at the molecular level.
(5) Polyamide resin E
Polyamide resin (P-3) described later in 94% by mass, dodecyldihexylmethylammonium swelling treatment swellable layered silicate (MEE manufactured by Co-op Chemical Co., Ltd., particle size 8 μm), 6% by mass, co-directional twin screw extruder (Toshiba Machine) The resin composition, which was supplied to the main supply port of TEM37BS manufactured and melted and kneaded, and taken up in a strand form from the die, was cooled and solidified through a water tank, and was cut with a pelletizer to obtain pellets of the resin composition. The extrusion conditions were a temperature setting of 270 to 290 ° C., a screw rotation speed of 200 rpm, and a discharge rate of 15 kg / h. The silicate layer was 4.2% by mass, and the relative viscosity measured by the viscosity measurement method described later was 1.8. When the wide angle X-ray diffraction measurement was performed on the polyamide resin pellets, the peak in the thickness direction of montmorillonite disappeared completely, and it was found that montmorillonite was uniformly dispersed in the polyamide resin at the molecular level.
(6) Polyamide resin (P-1)
Unit 6 nylon 6 “A1030BRL” was used. The relative viscosity measured by the viscosity measurement method described later was 2.5.
(7) Polyamide resin nylon 66 (P-2)
Unitika "A125" was used. The relative viscosity measured by the viscosity measurement method described later was 2.8.
(8) Polyamide resin nylon 11 (P-3)
“BMNO TLD” manufactured by Arkema was used. The relative viscosity measured by the viscosity measurement method described later was 1.8.

(B) Glass fiber (1) Glass fiber A
Flat glass fiber having an oval cross section with a major / minor diameter ratio of 2 (Nittobo CSH3PA870, with silane surface treatment)
・ Glass fiber B
Flat glass fiber having an oval cross section with a major / minor diameter ratio of 4 (Nittobo CSG3PA820, with silane surface treatment)
・ Glass fiber C
Glass fiber having a circular cross section with a diameter of 10 μm and a length of 3 mm (Nittobo CS3J-451, with silane surface treatment)
(C) Organic compound (1) Organic compound A
Trimethylolpropane polyglycidyl ether (SR-TMP manufactured by Sakamoto Pharmaceutical Co., Ltd.)
・ Organic compound B
Styrene / maleic anhydride copolymer (Hercules)
・ Organic compound C
Polyglycerin polyglycidyl ether (SR-4GL manufactured by Sakamoto Yakuhin Co., Ltd.)
・ Organic compound D
Triglycidyl isocyanurate (TEPIC manufactured by Nissan Chemical Co., Ltd.)
2 Measuring Method (1) Relative Viscosity of Polyamide Resin Dry pellets of the polyamide resin composition are dissolved in 96% by mass concentrated sulfuric acid so that the concentration of the polyamide resin component becomes 1 g / dl in consideration of the inorganic ash content. The inorganic component was filtered off with a G-3 glass filter and then subjected to measurement. The measurement was performed at 25 ° C. using an Ubbelohde viscometer.
(2) Inorganic ash content of the polyamide resin composition The dry pellets of the polyamide resin composition are precisely weighed in a magnetic crucible and the residue after incineration for 15 hours in an electric furnace maintained at 500 ° C. is used as the inorganic ash, according to the following formula: The inorganic ash content was determined.
Inorganic ash content (% by mass) = {Inorganic ash content (g)} / {Total mass of sample before incineration (g)} × 100
(3) Flexural modulus Test pieces having a length of 150 mm, a width of 10 mm, and a thickness of 3 mm were injection-molded with one gate, and measured at 23 ° C. in accordance with ASTM D790.
(4) Flexural modulus of weld (weld strength)
A test piece having a length of 150 mm, a width of 10 mm, and a thickness of 3 mm was injection-molded with a two-point gate from both ends, and the weld part formed at the center part was (2) similar to the flexural modulus, in accordance with ASTM D790. Measured at 23 ° C.
(5) Warpage amount A disk with a thickness of 1.6 mm and a diameter of 100 mm was injection-molded with a side gate, left standing at 23 ° C. in an absolutely dry state for 24 hours, and then left to stand on a horizontal plate. The distance from the horizontal plate was measured. The amount of warpage was determined by the following equation.
Reference points a and b: 2 points grounded on the horizontal board
Warpage points c and d: 2 points with large warpage Warpage amount (mm) = (c + d) / 2− (a + b) / 2
The amount of warpage determined by the above method is practically preferably 1.0 mm or less, and a warp amount of 1.0 mm is regarded as acceptable.
(6) The appearance molded product was visually observed, and the surface smoothness was impaired or the glass floated was rejected.

Example 1
100 parts by mass of polyamide resin A is supplied to the main supply port of the same-direction twin-screw extruder (TEM37BS manufactured by Toshiba Machine) using a continuous quantitative supply device manufactured by Kubota Corporation, melted and kneaded, and a predetermined amount from the liquid injection hole in the middle Organic compound A was supplied using a liquid injection meter. Further, 10 parts by mass of the glass fiber A was supplied from the side feeder, and the resin composition taken into a strand from the die was cooled and solidified through a water tank, and was cut with a pelletizer to obtain a polyamide resin composition pellet. The extrusion conditions were a temperature setting of 250 to 270 ° C., a screw rotation speed of 250 rpm, a discharge rate of 35 kg / h, and a resin temperature of 260 ° C. of the resin composition coming out of the die.
Next, the obtained polyamide resin composition pellets were injection molded under conditions of a cylinder temperature of 270 ° C. and a mold temperature of 100 ° C. using an injection molding machine (EC100 manufactured by Toshiba Machine Co., Ltd.), and various physical property measurement test pieces were prepared. A test was conducted. The results are shown in Table 2.

Examples 2-9
Except having set it as the component ratio shown in Table 2, the test piece was created similarly to Example 1, and various evaluation tests were done. The results are shown in Table 2.
Example 10
Melt kneading was performed in the same manner as in Example 1 except that the extrusion temperature condition during melt kneading was 270 to 290 ° C. The resin temperature of the resin composition coming out of the die was 280 ° C. Moreover, except that the cylinder temperature at the time of injection molding was 290 ° C., the same injection molding as in Example 1 was performed to obtain various molded products, and an evaluation test was performed. The results are shown in Table 2.
Example 11
Melt kneading was performed in the same manner as in Example 1 except that the extrusion temperature condition during melt kneading was 230 to 250 ° C. The resin temperature of the resin composition coming out of the die was 240 ° C. Moreover, except that the cylinder temperature at the time of injection molding was set to 250 ° C., the same injection molding as in Example 1 was performed to obtain various molded products, and an evaluation test was performed. The results are shown in Table 2.

Comparative Examples 1-7
Except having set it as the component ratio shown in Table 3, the test piece was created similarly to Example 1, and various evaluation tests were done. The results are shown in Table 3.

  In the examples, a glass fiber reinforced polyamide resin composition having excellent weld rigidity in addition to low warpage and rigidity by using a glass fiber having an oval cross section, an organic compound, and a swellable layered silicate in combination. was gotten.

  In Comparative Example 1, the amount of flat glass fibers was small, so the warpage amount greatly exceeded 1.0 mm, and the weld strength was low.

  In Comparative Example 2, since the amount of the flat glass fiber was too large, the fluidity of the resin composition was greatly reduced and the appearance was poor.

  Since the comparative example 3 used the glass fiber of the circular cross section which is not a flat glass fiber, the curvature amount became large.

  In Comparative Example 4, since the nylon resin containing no swellable layered silicate was used, the weld strength was low.

In Comparative Example 5, since no organic compound was blended, the weld strength was extremely low.
In Comparative Example 6, the weld strength was remarkably low because the blending amount of the organic compound was too small.

In Comparative Example 7, since the compounding amount of the organic compound was too large, the fluidity of the resin composition at the time of melt-kneading was greatly reduced and formed into a ball shape, and the strand could not be taken up. Since resin pellets could not be obtained, various evaluation tests other than relative viscosity could not be performed.

It is a figure which shows a measuring point with the measuring method of the curvature amount of this invention.

Claims (5)

10 to 50 parts by mass of flat glass fiber having a flat cross section with a major axis / minor axis ratio of 1.5 to 10 is blended with 100 parts by mass of the polyamide resin in which the silicate layer of the swellable layered silicate is dispersed. A polyamide resin composition obtained by mixing 0.05 to 4.0 parts by mass of an organic compound having two or more functional groups in one molecule. Polyamide resin composition.
  The organic compound according to claim 1 is one or more organic compounds selected from trimethylolpropane polyglycidyl ether, polyglycerin polyglycidyl ether, triglycidyl isocyanurate, and a styrene / maleic anhydride copolymer. A polyamide resin composition.   A polyamide resin composition according to claim 1 or 2, wherein the polyamide resin is one polyamide selected from nylon 6, nylon 66, and nylon 11.   The flat glass fiber according to any one of claims 1 to 3, which is a glass fiber having a modified cross-sectional shape of any one of a gourd type, an eyebrows type, an oval shape, an elliptical shape, and a rectangular shape, and a silane coupling agent, A polyamide resin composition comprising a surface treatment with one or more coupling agents selected from a titanium coupling agent and a zirconia coupling agent.   The resin molded product formed by shape | molding the polyamide resin composition in any one of Claims 1-4.